Commit Graph

13200 Commits

Author SHA1 Message Date
Peter Zijlstra
8c79a045fd sched/events: Revert trace_sched_stat_sleeptime()
Commit 1ac9bc69 ("sched/tracing: Add a new tracepoint for sleeptime")
added a new sched:sched_stat_sleeptime tracepoint.

It's broken: the first sample we get on a task might be bad because
of a stale sleep_start value that wasn't reset at the last task switch
because the tracepoint was not active.

It also breaks the existing schedstat samples due to the side
effects of:

-               se->statistics.sleep_start = 0;
...
-               se->statistics.block_start = 0;

Nor do I see means to fix it without adding overhead to the scheduler
fast path, which I'm not willing to for the sake of redundant
instrumentation.

Most importantly, sleep time information can already be constructed
by tracing context switches and wakeups, and taking the timestamp
difference between the schedule-out, the wakeup and the schedule-in.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-pc4c9qhl8q6vg3bs4j6k0rbd@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-22 12:06:55 +01:00
Jason Baron
a746e3cc98 jump label: Fix compiler warning
While cross-compiling on sparc64, I found:

kernel/jump_label.c: In function 'jump_label_update':
kernel/jump_label.c:447:40: warning: cast from pointer to
integer of different size [-Wpointer-to-int-cast]

Fix by casting to 'unsigned long'.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: davem@davemloft.net
Cc: ddaney.cavm@gmail.com
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/08026cbc6df80619cae833ef1ebbbc43efab69ab.1329851692.git.jbaron@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-22 07:59:40 +01:00
Jason Baron
fadf0464b8 jump label: Add a WARN() if jump label key count goes negative
The count on a jump label key should never go negative. Add a
WARN() to check for this condition.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: rostedt@goodmis.org
Cc: mathieu.desnoyers@efficios.com
Cc: davem@davemloft.net
Cc: ddaney.cavm@gmail.com
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/3c68556121be4d1920417a3fe367da1ec38246b4.1329851692.git.jbaron@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-22 07:59:39 +01:00
Hugh Dickins
1cc85961e2 rcu: Stop spurious warnings from synchronize_sched_expedited
synchronize_sched_expedited() is spamming CONFIG_DEBUG_PREEMPT=y
users with an unintended warning from the cpu_is_offline() check: use
raw_smp_processor_id() instead of smp_processor_id() there.

Because the warning is under a get_online_cpus(), it is not possible
for any CPUs to go offline, though it is quite possible that the
task might migrate between the raw_smp_processor_id() and the check
of cpu_is_offline().  This is not a problem because the task cannot
migrate from an offline CPU to an online one or vice versa.  The point
of the check is to verify that synchronize_sched_expedited() is not
called from an offline CPU, for example, from a CPU_DYING notifier, or,
more important, from an outgoing CPU making its way from its CPU_DYING
notifiers to the idle loop.

Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 15:33:34 -08:00
Frederic Weisbecker
3ce3230a0c cgroup: Walk task list under tasklist_lock in cgroup_enable_task_cg_list
Walking through the tasklist in cgroup_enable_task_cg_list() inside
an RCU read side critical section is not enough because:

- RCU is not (yet) safe against while_each_thread()

- If we use only RCU, a forking task that has passed cgroup_post_fork()
  without seeing use_task_css_set_links == 1 is not guaranteed to have
  its child immediately visible in the tasklist if we walk through it
  remotely with RCU. In this case it will be missing in its css_set's
  task list.

Thus we need to traverse the list (unfortunately) under the
tasklist_lock. It makes us safe against while_each_thread() and also
make sure we see all forked task that have been added to the tasklist.

As a secondary effect, reading and writing use_task_css_set_links are
now well ordered against tasklist traversing and modification. The new
layout is:

CPU 0                                      CPU 1

use_task_css_set_links = 1                write_lock(tasklist_lock)
read_lock(tasklist_lock)                  add task to tasklist
do_each_thread() {                        write_unlock(tasklist_lock)
	add thread to css set links       if (use_task_css_set_links)
} while_each_thread()                         add thread to css set links
read_unlock(tasklist_lock)

If CPU 0 traverse the list after the task has been added to the tasklist
then it is correctly added to the css set links. OTOH if CPU 0 traverse
the tasklist before the new task had the opportunity to be added to the
tasklist because it was too early in the fork process, then CPU 1
catches up and add the task to the css set links after it added the task
to the tasklist. The right value of use_task_css_set_links is guaranteed
to be visible from CPU 1 due to the LOCK/UNLOCK implicit barrier properties:
the read_unlock on CPU 0 makes the write on use_task_css_set_links happening
and the write_lock on CPU 1 make the read of use_task_css_set_links that comes
afterward to return the correct value.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Mandeep Singh Baines <msb@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:46:47 -08:00
Frederic Weisbecker
9a4b430451 cgroup: Remove wrong comment on cgroup_enable_task_cg_list()
Remove the stale comment about RCU protection. Many callers
(all of them?) of cgroup_enable_task_cg_list() don't seem
to be in an RCU read side critical section. Besides, RCU is
not helpful to protect against while_each_thread().

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Mandeep Singh Baines <msb@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:46:43 -08:00
Paul E. McKenney
696a02cc16 rcu: Hold off RCU_FAST_NO_HZ after timer posted
This commit handles workloads that transition quickly between idle and
non-idle, and where the CPU's callbacks cannot be invoked, but where
RCU does not have anything immediate for the CPU to do.  Without this
patch, the RCU_FAST_NO_HZ code can be invoked repeatedly on each entry
to idle.  The commit sets the per-CPU rcu_dyntick_holdoff variable to
hold off further attempts for a tick.

Reported-by: "Abou Gazala, Neven M" <neven.m.abou.gazala@intel.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:42:30 -08:00
Paul E. McKenney
c3ce910b14 rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop
If a softirq is pending, the current CPU has RCU callbacks pending,
and RCU does not immediately need anything from this CPU, then the
current code resets the RCU_FAST_NO_HZ state machine.  This means that
upon exit from the subsequent softirq handler, RCU_FAST_NO_HZ will
try really hard to force RCU into dyntick-idle mode.  And if the same
conditions hold after a few tries (determined by RCU_IDLE_OPT_FLUSHES),
the same situation can repeat, possibly endlessly.  This scenario is
not particularly good for battery lifetime.

This commit therefore suppresses the early exit from the RCU_FAST_NO_HZ
state machine in the case where there is a softirq pending.  This change
forces the state machine to retain its memory, and to enter holdoff if
this condition persists.

Reported-by: "Abou Gazala, Neven M" <neven.m.abou.gazala@intel.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:42:11 -08:00
Paul E. McKenney
8a2ecf474d rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections
RCU, RCU-bh, and RCU-sched read-side critical sections are forbidden
in the inner idle loop, that is, between the rcu_idle_enter() and the
rcu_idle_exit() -- RCU will happily ignore any such read-side critical
sections.  However, things like powertop need tracepoints in the inner
idle loop.

This commit therefore provides an RCU_NONIDLE() macro that can be used to
wrap code in the idle loop that requires RCU read-side critical sections.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
2012-02-21 09:06:13 -08:00
Paul E. McKenney
29e37d8141 rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit()
Use of RCU in the idle loop is incorrect, quite a few instances of
just that have made their way into mainline, primarily event tracing.
The problem with RCU read-side critical sections on CPUs that RCU believes
to be idle is that RCU is completely ignoring the CPU, along with any
attempts and RCU read-side critical sections.

The approaches of eliminating the offending uses and of pushing the
definition of idle down beyond the offending uses have both proved
impractical.  The new approach is to encapsulate offending uses of RCU
with rcu_idle_exit() and rcu_idle_enter(), but this requires nesting
for code that is invoked both during idle and and during normal execution.
Therefore, this commit modifies rcu_idle_enter() and rcu_idle_exit() to
permit nesting.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
2012-02-21 09:06:12 -08:00
Paul E. McKenney
ce5df97be5 rcu: Remove redundant check for rcu_head misalignment
There is now an unconditional check for rcu_head misalignment in
__call_rcu(), so remove the old conditional one in debug_rcu_head_queue().

Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:11 -08:00
Julia Lawall
3c1b1ce00d PTR_ERR should be called before its argument is cleared.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e,e1;
constant c;
@@

*e = c
... when != e = e1
    when != &e
    when != true IS_ERR(e)
*PTR_ERR(e)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:10 -08:00
Paul E. McKenney
7129d383d9 rcu: Trace only after NULL-pointer check
Fix a bonehead error introduced when adding event tracing to rcutorture.
Move the traces to follow the NULL-pointer checks.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:09 -08:00
Paul E. McKenney
236fefafe5 rcu: Call out dangers of expedited RCU primitives
The expedited RCU primitives can be quite useful, but they have some
high costs as well.  This commit updates and creates docbook comments
calling out the costs, and updates the RCU documentation as well.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:08 -08:00
Paul E. McKenney
2036d94a7b rcu: Rework detection of use of RCU by offline CPUs
Because newly offlined CPUs continue executing after completing the
CPU_DYING notifiers, they legitimately enter the scheduler and use
RCU while appearing to be offline.  This calls for a more sophisticated
approach as follows:

1.	RCU marks the CPU online during the CPU_UP_PREPARE phase.

2.	RCU marks the CPU offline during the CPU_DEAD phase.

3.	Diagnostics regarding use of read-side RCU by offline CPUs use
	RCU's accounting rather than the cpu_online_map.  (Note that
	__call_rcu() still uses cpu_online_map to detect illegal
	invocations within CPU_DYING notifiers.)

4.	Offline CPUs are prevented from hanging the system by
	force_quiescent_state(), which pays attention to cpu_online_map.
	Some additional work (in a later commit) will be needed to
	guarantee that force_quiescent_state() waits a full jiffy before
	assuming that a CPU is offline, for example, when called from
	idle entry.  (This commit also makes the one-jiffy wait
	explicit, since the old-style implicit wait can now be defeated
	by RCU_FAST_NO_HZ and by rcutorture.)

This approach avoids the false positives encountered when attempting to
use more exact classification of CPU online/offline state.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:07 -08:00
Paul E. McKenney
c5fdcec927 lockdep: Add CPU-idle/offline warning to lockdep-RCU splat
It is illegal to use RCU from a CPU that has reported idleness or
offlinedness to RCU.  However, it can be quite difficult to determine
from a stack trace whether or not a given CPU is idle or offline.
Therefore, this commit adds idle/offline diagnostics to the lockdep-RCU
error message.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:06 -08:00
Paul E. McKenney
c0cfbbb0d4 rcu: No interrupt disabling for rcu_prepare_for_idle()
The rcu_prepare_for_idle() function is always called with interrupts
disabled, so there is no reason to disable interrupts again within
rcu_prepare_for_idle().  Therefore, this commit removes all of the
interrupt disabling, also removing a latent disabling-unbalance bug.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:05 -08:00
Paul E. McKenney
3d3b7db0a2 rcu: Move synchronize_sched_expedited() to rcutree.c
Now that TREE_RCU and TREE_PREEMPT_RCU no longer do anything different
for the single-CPU case, there is no need for multiple definitions of
synchronize_sched_expedited().  It is no longer in any sense a plug-in,
so move it from kernel/rcutree_plugin.h to kernel/rcutree.c.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:04 -08:00
Paul E. McKenney
c0d6d01bff rcu: Check for illegal use of RCU from offlined CPUs
Although it is legal to use RCU during early boot, it is anything
but legal to use RCU at runtime from an offlined CPU.  After all, RCU
explicitly ignores offlined CPUs.  This commit therefore adds checks
for runtime use of RCU from offlined CPUs.

These checks are not perfect, in particular, they can be subverted
through use of things like rcu_dereference_raw().  Note that it is not
possible to put checks in rcu_read_lock() and friends due to the fact
that these primitives are used in code that might be used under either
RCU or lock-based protection, which means that checking rcu_read_lock()
gets you fat piles of false positives.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:06:03 -08:00
Paul E. McKenney
c13f3757d0 rcu: Add CPU-stall capability to rcutorture
Add module parameters to rcutorture that induce a CPU stall.
The stall_cpu parameter specifies how long to stall in seconds,
defaulting to zero, which indicates no stalling is to be undertaken.
The stall_cpu_holdoff parameter specifies how many seconds after
insmod (or boot, if rcutorture is built into the kernel) that this
stall is to start.  The default value for stall_cpu_holdoff is ten
seconds.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:52 -08:00
Paul E. McKenney
9b9ec9b90e rcutorture: Permit holding off CPU-hotplug operations during boot
When rcutorture is started automatically at boot time, it might well
also start CPU-hotplug operations at that time, which might not be
desirable.  This commit therefore adds an rcutorture parameter that
allows CPU-hotplug operations to be held off for the specified number
of seconds after the start of boot.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:50 -08:00
Paul E. McKenney
a858af2875 rcu: Print scheduling-clock information on RCU CPU stall-warning messages
There have been situations where RCU CPU stall warnings were caused by
issues in scheduling-clock timer initialization.  To make it easier to
track these down, this commit causes the RCU CPU stall-warning messages
to print out the number of scheduling-clock interrupts taken in the
current grace period for each stalled CPU.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:49 -08:00
Paul E. McKenney
13cfcca0e4 rcu: Set RCU CPU stall times via sysfs
The default CONFIG_RCU_CPU_STALL_TIMEOUT value of 60 seconds has served
Linux users well for production use for quite some time.  However, for
debugging, there will be more than three minutes between subsequent
stall-warning messages.  This can be an annoyingly long wait if you
are trying to work out where the offending infinite loop is hiding.

Therefore, this commit provides a rcu_cpu_stall_timeout sysfs
parameter that may be adjusted at boot time and at runtime to speed
up debugging.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:48 -08:00
Paul E. McKenney
27565d64a4 rcu: Remove #ifdef CONFIG_SMP from TREE_RCU
Now that both TINY_RCU and TINY_PREEMPT_RCU have been in place for awhile,
it is time to remove UP support from TREE_RCU, which is what this commit
does.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:47 -08:00
Paul E. McKenney
c44e2cddac rcu: Check for idle-loop entry while in RCU read-side critical section
The inner idle loop is an extended quiescent state for all flavors
of RCU, but there have been recent bug involving use of RCU read-side
primitives from within the idle loop.  Therefore, this commit enlists
lockdep-RCU to detect attempts to enter the inner idle loop while in
an RCU read-side critical section, emitting a lockdep-RCU splat if so.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:45 -08:00
Paul E. McKenney
30fbcc90b0 rcu: Clean up straggling rcu_preempt_needs_cpu() name
The recent updates to RCU_CPU_FAST_NO_HZ have an rcu_needs_cpu() that
does more than just check for callbacks, so get the name for
rcu_preempt_needs_cpu() consistent with that change, now calling it
rcu_preempt_cpu_has_callbacks().

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:44 -08:00
Paul E. McKenney
1aa03f1188 rcu: Simplify unboosting checks
This is a port of commit #82e78d80 from TREE_PREEMPT_RCU to
TINY_PREEMPT_RCU.

This commit uses the fact that current->rcu_boost_mutex is set
any time that the RCU_READ_UNLOCK_BOOSTED flag is set in the
current->rcu_read_unlock_special bitmask.  This allows tests of
the bit to be changed to tests of the pointer, which in turn allows
the RCU_READ_UNLOCK_BOOSTED flag to be eliminated.

Please note that the check of current->rcu_read_unlock_special need not
change because any time that RCU_READ_UNLOCK_BOOSTED was set, so was
RCU_READ_UNLOCK_BLOCKED.  Therefore, __rcu_read_unlock() can continue
testing current->rcu_read_unlock_special for non-zero, as before.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:43 -08:00
Paul E. McKenney
8762705ad4 rcu: Inform RCU of irq_exit() activity
This is a port to TINY_RCU of Peter Zijlstra's commit #ec433f0c5

The rcu_read_unlock_special() function relies on in_irq() to exclude
scheduler activity from interrupt level.  This fails because exit_irq()
can invoke the scheduler after clearing the preempt_count() bits that
in_irq() uses to determine that it is at interrupt level.  This situation
can result in failures as follows:

     $task			IRQ		SoftIRQ

     rcu_read_lock()

     /* do stuff */

     <preempt> |= UNLOCK_BLOCKED

     rcu_read_unlock()
       --t->rcu_read_lock_nesting

    			irq_enter();
    			/* do stuff, don't use RCU */
    			irq_exit();
    			  sub_preempt_count(IRQ_EXIT_OFFSET);
    			  invoke_softirq()

    					ttwu();
    					  spin_lock_irq(&pi->lock)
    					  rcu_read_lock();
    					  /* do stuff */
    					  rcu_read_unlock();
    					    rcu_read_unlock_special()
    					      rcu_report_exp_rnp()
    					        ttwu()
    					          spin_lock_irq(&pi->lock) /* deadlock */

       rcu_read_unlock_special(t);

This can be triggered 'easily' because invoke_softirq() immediately does
a ttwu() of ksoftirqd/# instead of doing the in-place softirq stuff first,
but even without that the above happens.

Cure this by also excluding softirqs from the rcu_read_unlock_special()
handler and ensuring the force_irqthreads ksoftirqd/# wakeup is done
from full softirq context.

It is also necessary to delay the ->rcu_read_lock_nesting decrement until
after rcu_read_unlock_special().  This delay is handled by the commit
"Protect __rcu_read_unlock() against scheduler-using irq handlers".

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:42 -08:00
Paul E. McKenney
768dfffdff rcu: Prevent RCU callbacks from executing before scheduler initialized
This is a port of commit #b0d3041 from TREE_RCU to TREE_PREEMPT_RCU.

Under some rare but real combinations of configuration parameters, RCU
callbacks are posted during early boot that use kernel facilities that are
not yet initialized.  Therefore, when these callbacks are invoked, hard
hangs and crashes ensue.  This commit therefore prevents RCU callbacks
from being invoked until after the scheduler is fully up and running,
as in after multiple tasks have been spawned.

It might well turn out that a better approach is to identify the specific
RCU callbacks that are causing this problem, but that discussion will
wait until such time as someone really needs an RCU callback to be invoked
(as opposed to merely registered) during early boot.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:41 -08:00
Paul E. McKenney
afef20540f rcu: Streamline code produced by __rcu_read_unlock()
This is a port of commit #be0e1e21 to TINY_PREEMPT_RCU.  This uses
noinline to prevent rcu_read_unlock_special() from being inlined into
__rcu_read_unlock().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:40 -08:00
Paul E. McKenney
26861faf89 rcu: Protect __rcu_read_unlock() against scheduler-using irq handlers
This commit ports commit #10f39bb1b2 (rcu: protect __rcu_read_unlock()
against scheduler-using irq handlers) from TREE_PREEMPT_RCU to
TINY_PREEMPT_RCU.  The following is a corresponding port of that
commit message.

The addition of RCU read-side critical sections within runqueue and
priority-inheritance critical sections introduced some deadlocks,
for example, involving interrupts from __rcu_read_unlock() where the
interrupt handlers call wake_up().  This situation can cause the
instance of __rcu_read_unlock() invoked from interrupt to do some
of the processing that would otherwise have been carried out by the
task-level instance of __rcu_read_unlock().  When the interrupt-level
instance of __rcu_read_unlock() is called with a scheduler lock held from
interrupt-entry/exit situations where in_irq() returns false, deadlock can
result.  Of course, in a UP kernel, there are not really any deadlocks,
but the upper-level critical section can still be be fatally confused
by the lower-level critical section changing things out from under it.

This commit resolves these deadlocks by using negative values of the
per-task ->rcu_read_lock_nesting counter to indicate that an instance of
__rcu_read_unlock() is in flight, which in turn prevents instances from
interrupt handlers from doing any special processing.  Note that nested
rcu_read_lock()/rcu_read_unlock() pairs are still permitted, but they will
never see ->rcu_read_lock_nesting go to zero, and will therefore never
invoke rcu_read_unlock_special(), thus preventing them from seeing the
RCU_READ_UNLOCK_BLOCKED bit should it be set in ->rcu_read_unlock_special.
This patch also adds a check for ->rcu_read_unlock_special being negative
in rcu_check_callbacks(), thus preventing the RCU_READ_UNLOCK_NEED_QS
bit from being set should a scheduling-clock interrupt occur while
__rcu_read_unlock() is exiting from an outermost RCU read-side critical
section.

Of course, __rcu_read_unlock() can be preempted during the time that
->rcu_read_lock_nesting is negative.  This could result in the setting
of the RCU_READ_UNLOCK_BLOCKED bit after __rcu_read_unlock() checks it,
and would also result it this task being queued on the corresponding
rcu_node structure's blkd_tasks list.  Therefore, some later RCU read-side
critical section would enter rcu_read_unlock_special() to clean up --
which could result in deadlock (OK, OK, fatal confusion) if that RCU
read-side critical section happened to be in the scheduler where the
runqueue or priority-inheritance locks were held.

To prevent the possibility of fatal confusion that might result from
preemption during the time that ->rcu_read_lock_nesting is negative,
this commit also makes rcu_preempt_note_context_switch() check for
negative ->rcu_read_lock_nesting, thus refraining from queuing the task
(and from setting RCU_READ_UNLOCK_BLOCKED) if we are already exiting
from the outermost RCU read-side critical section (in other words,
we really are no longer actually in that RCU read-side critical
section).  In addition, rcu_preempt_note_context_switch() invokes
rcu_read_unlock_special() to carry out the cleanup in this case, which
clears out the ->rcu_read_unlock_special bits and dequeues the task
(if necessary), in turn avoiding needless delay of the current RCU grace
period and needless RCU priority boosting.

It is still illegal to call rcu_read_unlock() while holding a scheduler
lock if the prior RCU read-side critical section has ever had both
preemption and irqs enabled.  However, the common use case is legal,
namely where then entire RCU read-side critical section executes with
irqs disabled, for example, when the scheduler lock is held across the
entire lifetime of the RCU read-side critical section.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:39 -08:00
Paul E. McKenney
f38bd1020f rcu: Remove single-rcu_node optimization in rcu_start_gp()
The grace-period initialization sequence in rcu_start_gp() has a special
case for systems where the rcu_node tree is a single rcu_node structure.
This made sense some years ago when systems were smaller and up to 64
CPUs could share a single rcu_node structure, but now that large systems
are common and a given leaf rcu_node structure can support only 16 CPUs
(due to lock contention on the rcu_node's ->lock field), this optimization
is almost never taken.  And even the small mobile platforms that might
make use of it might rather have the kernel text reduction.

Therefore, this commit removes the check for single-rcu_node trees.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-02-21 09:03:38 -08:00
Paul E. McKenney
a50c3af910 rcu: Don't make callbacks go through second full grace period
RCU's current CPU-offline code path dumps all of the outgoing CPU's
callbacks onto the RCU_NEXT_TAIL portion of the surviving CPU's
callback list.  This means that all the ready-to-invoke callbacks from
the outgoing CPU must wait for another full RCU grace period.  This was
just fine when CPU-hotplug events were rare, but there is increasing
evidence that users are planning to make increasing use of CPU hotplug.

Therefore, this commit changes the callback-dumping procedure so that
callbacks that are ready to invoke are moved to the RCU_DONE_TAIL
portion of the surviving CPU's callback list.  This avoids running
these callbacks through a second unnecessary grace period.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:37 -08:00
Paul E. McKenney
8146c4e2e2 rcu: Check for callback invocation from offline CPUs
Because quiescent states are now reported from offline CPUs in
CPU_DYING state, there is some possibility that such a CPU might
note the end of a grace period and attempt to start invoking
callbacks.  This would be a very bad thing, and is supposed to
be prevented by the fact that the CPU_DYING CPU gets rid of all
its callbacks before reporting the quiescent state.  However,
there is other CPU-offline code in the kernel, and it is quite
possible that someone will invoke RCU core processing from that
code.  Therefore, this commit adds a warning for this case.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:37 -08:00
Paul E. McKenney
778d250a29 rcu: Limit lazy-callback duration
Currently, a given CPU is permitted to remain in dyntick-idle mode
indefinitely if it has only lazy RCU callbacks queued.  This is vulnerable
to corner cases in NUMA systems, so limit the time to six seconds by
default.  (Currently controlled by a cpp macro.)

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:36 -08:00
Paul E. McKenney
091541bbdb rcu: Make rcutorture flag online/offline failures
Make rcutorture check for CPU-hotplug failures and complain if there
were any.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:35 -08:00
Paul E. McKenney
e560140008 rcu: Simplify offline processing
Move ->qsmaskinit and blkd_tasks[] manipulation to the CPU_DYING
notifier.  This simplifies the code by eliminating a potential
deadlock and by reducing the responsibilities of force_quiescent_state().
Also rename functions to make their connection to the CPU-hotplug
stages explicit.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:34 -08:00
Paul E. McKenney
486e259340 rcu: Avoid waking up CPUs having only kfree_rcu() callbacks
When CONFIG_RCU_FAST_NO_HZ is enabled, RCU will allow a given CPU to
enter dyntick-idle mode even if it still has RCU callbacks queued.
RCU avoids system hangs in this case by scheduling a timer for several
jiffies in the future.  However, if all of the callbacks on that CPU
are from kfree_rcu(), there is no reason to wake the CPU up, as it is
not a problem to defer freeing of memory.

This commit therefore tracks the number of callbacks on a given CPU
that are from kfree_rcu(), and avoids scheduling the timer if all of
a given CPU's callbacks are from kfree_rcu().

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:25 -08:00
Paul E. McKenney
0bb7b59d6e rcu: Add diagnostic for misaligned rcu_head structures
The push for energy efficiency will require that RCU tag rcu_head
structures to indicate whether or not their invocation is time critical.
This tagging is best carried out in the bottom bits of the ->next
pointers in the rcu_head structures.  This tagging requires that the
rcu_head structures be properly aligned, so this commit adds the required
diagnostics.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:24 -08:00
Paul E. McKenney
fe15d706cf rcu: Add lockdep-RCU checks for simple self-deadlock
It is illegal to have a grace period within a same-flavor RCU read-side
critical section, so this commit adds lockdep-RCU checks to splat when
such abuse is encountered.  This commit does not detect more elaborate
RCU deadlock situations.  These situations might be a job for lockdep
enhancements.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-02-21 09:03:23 -08:00
Jiri Olsa
5500fa5119 ftrace, perf: Add filter support for function trace event
Adding support to filter function trace event via perf
interface. It is now possible to use filter interface
in the perf tool like:

  perf record -e ftrace:function --filter="(ip == mm_*)" ls

The filter syntax is restricted to the the 'ip' field only,
and following operators are accepted '==' '!=' '||', ending
up with the filter strings like:

  ip == f1[, ]f2 ... || ip != f3[, ]f4 ...

with comma ',' or space ' ' as a function separator. If the
space ' ' is used as a separator, the right side of the
assignment needs to be enclosed in double quotes '"', e.g.:

  perf record -e ftrace:function --filter '(ip == do_execve,sys_*,ext*)' ls
  perf record -e ftrace:function --filter '(ip == "do_execve,sys_*,ext*")' ls
  perf record -e ftrace:function --filter '(ip == "do_execve sys_* ext*")' ls

The '==' operator adds trace filter with same effect as would
be added via set_ftrace_filter file.

The '!=' operator adds trace filter with same effect as would
be added via set_ftrace_notrace file.

The right side of the '!=', '==' operators is list of functions
or regexp. to be added to filter separated by space.

The '||' operator is used for connecting multiple filter definitions
together. It is possible to have more than one '==' and '!='
operators within one filter string.

Link: http://lkml.kernel.org/r/1329317514-8131-8-git-send-email-jolsa@redhat.com

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21 11:08:30 -05:00
Jiri Olsa
02aa3162ed ftrace: Allow to specify filter field type for ftrace events
Adding FILTER_TRACE_FN event field type for function tracepoint
event, so it can be properly recognized within filtering code.

Currently all fields of ftrace subsystem events share the common
field type FILTER_OTHER. Since the function trace fields need
special care within the filtering code we need to recognize it
properly, hence adding the FILTER_TRACE_FN event type.

Adding filter parameter to the FTRACE_ENTRY macro, to specify the
filter field type for the event.

Link: http://lkml.kernel.org/r/1329317514-8131-7-git-send-email-jolsa@redhat.com

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21 11:08:29 -05:00
Jiri Olsa
ced39002f5 ftrace, perf: Add support to use function tracepoint in perf
Adding perf registration support for the ftrace function event,
so it is now possible to register it via perf interface.

The perf_event struct statically contains ftrace_ops as a handle
for function tracer. The function tracer is registered/unregistered
in open/close actions.

To be efficient, we enable/disable ftrace_ops each time the traced
process is scheduled in/out (via TRACE_REG_PERF_(ADD|DELL) handlers).
This way tracing is enabled only when the process is running.
Intentionally using this way instead of the event's hw state
PERF_HES_STOPPED, which would not disable the ftrace_ops.

It is now possible to use function trace within perf commands
like:

  perf record -e ftrace:function ls
  perf stat -e ftrace:function ls

Allowed only for root.

Link: http://lkml.kernel.org/r/1329317514-8131-6-git-send-email-jolsa@redhat.com

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21 11:08:27 -05:00
Jiri Olsa
e59a0bff3e ftrace: Add FTRACE_ENTRY_REG macro to allow event registration
Adding FTRACE_ENTRY_REG macro so particular ftrace entries
could specify registration function and thus become accesible
via perf.

This will be used in upcomming patch for function trace.

Link: http://lkml.kernel.org/r/1329317514-8131-5-git-send-email-jolsa@redhat.com

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21 11:08:26 -05:00
Jiri Olsa
489c75c3b3 ftrace, perf: Add add/del tracepoint perf registration actions
Adding TRACE_REG_PERF_ADD and TRACE_REG_PERF_DEL to handle
perf event schedule in/out actions.

The add action is invoked for when the perf event is scheduled in,
while the del action is invoked when the event is scheduled out.

Link: http://lkml.kernel.org/r/1329317514-8131-4-git-send-email-jolsa@redhat.com

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21 11:08:25 -05:00
Jiri Olsa
ceec0b6fc7 ftrace, perf: Add open/close tracepoint perf registration actions
Adding TRACE_REG_PERF_OPEN and TRACE_REG_PERF_CLOSE to differentiate
register/unregister from open/close actions.

The register/unregister actions are invoked for the first/last
tracepoint user when opening/closing the event.

The open/close actions are invoked for each tracepoint user when
opening/closing the event.

Link: http://lkml.kernel.org/r/1329317514-8131-3-git-send-email-jolsa@redhat.com

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21 11:08:24 -05:00
Jiri Olsa
e248491ac2 ftrace: Add enable/disable ftrace_ops control interface
Adding a way to temporarily enable/disable ftrace_ops. The change
follows the same way as 'global' ftrace_ops are done.

Introducing 2 global ftrace_ops - control_ops and ftrace_control_list
which take over all ftrace_ops registered with FTRACE_OPS_FL_CONTROL
flag. In addition new per cpu flag called 'disabled' is also added to
ftrace_ops to provide the control information for each cpu.

When ftrace_ops with FTRACE_OPS_FL_CONTROL is registered, it is
set as disabled for all cpus.

The ftrace_control_list contains all the registered 'control' ftrace_ops.
The control_ops provides function which iterates ftrace_control_list
and does the check for 'disabled' flag on current cpu.

Adding 3 inline functions:
  ftrace_function_local_disable/ftrace_function_local_enable
  - enable/disable the ftrace_ops on current cpu
  ftrace_function_local_disabled
  - get disabled ftrace_ops::disabled value for current cpu

Link: http://lkml.kernel.org/r/1329317514-8131-2-git-send-email-jolsa@redhat.com

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21 11:08:23 -05:00
Steven Rostedt
5b34926114 tracing: Don't use p->len field to determine output in __print_*() functions
If more than one __print_*() function is used in a tracepoint
(__print_flags(), __print_symbols(), etc), then the temp seq buffer will
not be zero on entry. Using the temp seq buffer's length to know if
data has been printed or not in the current function is incorrect and
may produce incorrect results.

Currently, no in-tree tracepoint causes this bug, but new ones may
be created.

Cc: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21 11:08:13 -05:00
Andrey Vagin
e404b321db tracing: Don't print an extra separator of flags
If __print_flags() is used after another __print_*() function, the
temp seq_file buffer will not be empty on entry, and the delimiter will
be printed even though there's just one field. We get something like:

	|S

instead of just:

	S

This is because the length of the temp seq buffer is used to determine
if the delimiter is printed or not. But this algorithm fails when
the seq buffer is not empty on entry, and the delimiter will be printed
because it thinks that a previous field was already printed.

Link: http://lkml.kernel.org/r/1329650167-480655-1-git-send-email-avagin@openvz.org

Signed-off-by: Andrew Vagin <avagin@openvz.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-20 20:33:31 -05:00
Linus Torvalds
8ebbfb4957 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Assorted fixes, sat in -next for a week or so...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ocfs2: deal with wraparounds of i_nlink in ocfs2_rename()
  vfs: fix compat_sys_stat() handling of overflows in st_nlink
  quota: Fix deadlock with suspend and quotas
  vfs: Provide function to get superblock and wait for it to thaw
  vfs: fix panic in __d_lookup() with high dentry hashtable counts
  autofs4 - fix lockdep splat in autofs
  vfs: fix d_inode_lookup() dentry ref leak
2012-02-20 16:13:58 -08:00
H. Peter Anvin
6684ba202b compat: Add helper functions to read/write struct timeval, timespec
Add helper functions to read and write struct timeval and struct
timespec from userspace.  We already had helper functions for reading
and writing struct compat_timespec; add a set of functions to do the
same with struct timeval, and add a second suite of functions which
can be sensitive to COMPAT_USE_64BIT_TIME and access either 32- or
64-bit time structures.

This also exports these helper functions to modules.

Rename the existing inlines for converting between struct
compat_timeval and native struct timespec so we can have a saner
naming convention for the exported functions.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 12:48:47 -08:00
David Howells
1fd36adcd9 Replace the fd_sets in struct fdtable with an array of unsigned longs
Replace the fd_sets in struct fdtable with an array of unsigned longs and then
use the standard non-atomic bit operations rather than the FD_* macros.

This:

 (1) Removes the abuses of struct fd_set:

     (a) Since we don't want to allocate a full fd_set the vast majority of the
     	 time, we actually, in effect, just allocate a just-big-enough array of
     	 unsigned longs and cast it to an fd_set type - so why bother with the
     	 fd_set at all?

     (b) Some places outside of the core fdtable handling code (such as
     	 SELinux) want to look inside the array of unsigned longs hidden inside
     	 the fd_set struct for more efficient iteration over the entire set.

 (2) Eliminates the use of FD_*() macros in the kernel completely.

 (3) Permits the __FD_*() macros to be deleted entirely where not exposed to
     userspace.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20120216174954.23314.48147.stgit@warthog.procyon.org.uk
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
2012-02-19 10:30:57 -08:00
Bjorn Helgaas
69f1d475cc PM / Hibernate: print physical addresses consistently with other parts of kernel
Print physical address info in a style consistent with the %pR style used
elsewhere in the kernel.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-17 23:36:41 +01:00
Rafael J. Wysocki
bc25cf5089 PM / Sleep: Drop suspend_stats_update()
Since suspend_stats_update() is only called from pm_suspend(),
move its code directly into that function and remove the static
inline definition from include/linux/suspend.h.  Clean_up
pm_suspend() in the process.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
2012-02-17 23:36:23 +01:00
Rafael J. Wysocki
93e1ee43a7 PM / Sleep: Make enter_state() in kernel/power/suspend.c static
The enter_state() function in kernel/power/suspend.c should be
static and state_store() in kernel/power/suspend.c should call
pm_suspend() instead of it, so make that happen (which also reduces
code duplication related to suspend statistics).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
2012-02-17 23:36:10 +01:00
Rafael J. Wysocki
55ae451918 PM / Sleep: Unify kerneldoc comments in kernel/power/suspend.c
The kerneldoc comments in kernel/power/suspend.c are not formatted
in the same way and the quality of some of them is questionable.
Unify the formatting and improve the contents.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
2012-02-17 23:36:03 +01:00
Ingo Molnar
09bda4432a Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core 2012-02-17 12:55:07 +01:00
Grant Likely
a18dc81bf5 irq_domain: constify irq_domain_ops
Make irq_domain_ops pointer a constant to make it safer for multiple
instances to share the same ops pointer and change the irq_domain code
so that it does not modify the ops.

v4: Fix mismatched type reference in powerpc code

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:24 -07:00
Grant Likely
16b2e6e2f3 irq_domain: Create common xlate functions that device drivers can use
Rather than having each interrupt controller driver creating its own barely
unique .xlate function for irq_domain, create a library of translators which
any driver can use directly.

v5: - Remove irq_domain_xlate_pci().  It was incorrect.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:23 -07:00
Grant Likely
6b783f7c5d irq_domain: Remove irq_domain_add_simple()
irq_domain_add_simple() was a stop-gap measure until complete irq_domain
support was complete.  This patch removes the irq_domain_add_simple()
interface.

This patch also drops the explicit irq_domain initialization performed
by the mach-versatile code because the versatile interrupt controller
already has irq_domain support built into it.  This was a bug that was
hanging around quietly for a while, but with the full irq_domain which
actually verifies that irq_domain ranges are available it would cause
the registration to fail and the system wouldn't boot.

v4: Fixed number of irqs in mx5 gpio code
v2: Updated to pass in host_data pointer on irq_domain allocation.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Cc: Russell King <linux@arm.linux.org.uk>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:23 -07:00
Grant Likely
75294957be irq_domain: Remove 'new' irq_domain in favour of the ppc one
This patch removes the simplistic implementation of irq_domains and enables
the powerpc infrastructure for all irq_domain users.  The powerpc
infrastructure includes support for complex mappings between Linux and
hardware irq numbers, and can manage allocation of irq_descs.

This patch also converts the few users of irq_domain_add()/irq_domain_del()
to call irq_domain_add_legacy() instead.

v3: Fix bug that set up too many irqs in translation range.
v2: Fix removal of irq_alloc_descs() call in gic driver

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:23 -07:00
Grant Likely
1bc04f2cf8 irq_domain: Add support for base irq and hwirq in legacy mappings
Add support for a legacy mapping where irq = (hwirq - first_hwirq + first_irq)
so that a controller driver can allocate a fixed range of irq_descs and use
a simple calculation to translate back and forth between linux and hw irq
numbers.  This is needed to use an irq_domain with many of the ARM interrupt
controller drivers that manage their own irq_desc allocations.  Ultimately
the goal is to migrate those drivers to use the linear revmap, but doing it
this way allows each driver to be converted separately which makes the
migration path easier.

This patch generalizes the IRQ_DOMAIN_MAP_LEGACY method to use
(first_irq-first_hwirq) as the offset between hwirq and linux irq number,
and adds checks to make sure that the hwirq number does not exceed range
assigned to the controller.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:23 -07:00
Grant Likely
a8db8cf0d8 irq_domain: Replace irq_alloc_host() with revmap-specific initializers
Each revmap type has different arguments for setting up the revmap.
This patch splits up the generator functions so that each revmap type
can do its own setup and the user doesn't need to keep track of how
each revmap type handles the arguments.

This patch also adds a host_data argument to the generators.  There are
cases where the host_data pointer will be needed before the function returns.
ie. the legacy map calls the .map callback for each irq before returning.

v2: - Add void *host_data argument to irq_domain_add_*() functions
    - fixed failure to compile
    - Moved IRQ_DOMAIN_MAP_* defines into irqdomain.c

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:22 -07:00
Grant Likely
68700650e7 irq_domain: Remove references to old irq_host names
No functional changes.  Replaces non-exported references to 'host' with domain.
Does not change any symbol names referenced by other .c files.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:22 -07:00
Grant Likely
03848373ea irq_domain: remove NO_IRQ from irq domain code
zero always means no irq when using irq domains.  Get rid of the NO_IRQ
references.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:21 -07:00
Grant Likely
cc79ca691c irq_domain: Move irq_domain code from powerpc to kernel/irq
This patch only moves the code.  It doesn't make any changes, and the
code is still only compiled for powerpc.  Follow-on patches will generalize
the code for other architectures.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 01:37:49 -07:00
Thomas Gleixner
97ac984d2f Merge branch 'fortglx/3.4/time' of git://git.linaro.org/people/jstultz/linux into timers/core 2012-02-15 20:29:18 +01:00
Frederic Weisbecker
0a8a2e78b7 timer: Fix bad idle check on irq entry
idle_cpu() is called on irq entry to guess if we need to call
tick_check_idle(). This way we can catch up with jiffies if the tick
was stopped, stop accounting idle time during the interrupt and
maintain the sched clock if it is unstable.

But if we are going to exit the idle loop to schedule a new task (ie:
if we have a task in the runqueue or a remotely enqueued ttwu to
perform), the idle_cpu() check will return 0 such that we miss the
call to tick_check_idle() for all interrupts happening before we
schedule the new task.

As a result these interrupts and the softirqs coming along may deal
with stale jiffies values, bad sched clock values, and won't substract
their time from the idle time accounting.

Fix this with using is_idle_task() instead that strictly checks that
we are running the idle task, without caring about the fact we are
going to schedule a task soon.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/1327427984-23282-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 15:23:09 +01:00
Frederic Weisbecker
15f827be93 nohz: Remove ts->Einidle checks before restarting the tick
ts->inidle is set by tick_nohz_idle_enter() and unset by
tick_nohz_idle_exit(). However these two calls are assumed
to be always paired. This means that by the time we call
tick_nohz_idle_exit(), ts->inidle is supposed to be always
set to 1.

Remove the checks for ts->inidle in tick_nohz_idle_exit().
This simplifies a bit the code and improves its debuggability
(ie: ensure the call is paired with a tick_nohz_idle_enter()
call).

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/1327427984-23282-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 15:23:09 +01:00
Michal Hocko
430ee88195 nohz: Remove update_ts_time_stat from tick_nohz_start_idle
There is no reason to call update_ts_time_stat from tick_nohz_start_idle
anymore (after e0e37c20 sched: Eliminate the ts->idle_lastupdate field)
when we updated idle_lastupdate unconditionally.

We haven't set idle_active yet and do not provide last_update_time so
the whole call end up being just 2 wasted branches.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Link: http://lkml.kernel.org/r/1322755222-6951-1-git-send-email-mhocko@suse.cz
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 15:23:09 +01:00
Suresh Siddha
77b0d60c5a clockevents: Leave the broadcast device in shutdown mode when not needed
Platforms with Always Running APIC Timer doesn't use the broadcast timer
but the kernel is leaving the broadcast timer (HPET in this case)
in oneshot mode.

On these platforms, before the switch to oneshot mode, broadcast device is
actually in shutdown mode. Code checks for empty tick_broadcast_mask and
avoids going into the periodic mode.

During switch to oneshot mode, add the same tick_broadcast_mask checks in the
tick_broadcast_switch_to_oneshot() and avoid the broadcast device going into
the oneshot mode.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: john stultz <johnstul@us.ibm.com>
Cc: venki@google.com
Link: http://lkml.kernel.org/r/1320452301.15071.16.camel@sbsiddha-desk.sc.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 15:23:09 +01:00
Thomas Gleixner
81b40539e7 futex: Simplify return logic
No need to assign ret in each case and break. Simply return the result
of the handler function directly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@linux.intel.com>
2012-02-15 12:19:13 +01:00
Thomas Gleixner
59263b513c futex: Cover all PI opcodes with cmpxchg enabled check
Some of the newer futex PI opcodes do not check the cmpxchg enabled
variable and call unconditionally into the handling functions. Cover
all PI opcodes in a separate check.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@linux.intel.com>
2012-02-15 12:19:13 +01:00
Thomas Gleixner
b4bc724e82 genirq: Handle pending irqs in irq_startup()
An interrupt might be pending when irq_startup() is called, but the
startup code does not invoke the resend logic. In some cases this
prevents the device from issuing another interrupt which renders the
device non functional.

Call the resend function in irq_startup() to keep things going.

Reported-and-tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 11:56:59 +01:00
Thomas Gleixner
ac56376111 genirq: Unmask oneshot irqs when thread was not woken
When the primary handler of an interrupt which is marked IRQ_ONESHOT
returns IRQ_HANDLED or IRQ_NONE, then the interrupt thread is not
woken and the unmask logic of the interrupt line is never
invoked. This keeps the interrupt masked forever.

This was not noticed as most IRQ_ONESHOT users wake the thread
unconditionally (usually because they cannot access the underlying
device from hard interrupt context). Though this behaviour was nowhere
documented and not necessarily intentional. Some drivers can avoid the
thread wakeup in certain cases and run into the situation where the
interrupt line s kept masked.

Handle it gracefully.

Reported-and-tested-by: Lothar Wassmann <lw@karo-electronics.de>
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 11:56:59 +01:00
Grant Likely
7bb69bade0 irq_domain: Make irq_domain structure match powerpc's irq_host
Part of the series to unify the irq remapping mechanisms in the
kernel.  A follow up patch will copy the powerpc implementation into
kernel/irq/irqdomain.c, which will be a lot easier if the structures
are identical.

Where they differ, I've chose to use the powerpc names since there is
a lot more code using those names.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-14 14:06:48 -07:00
Grant Likely
e1964c50a8 irq_domain: Be less verbose
irq_domain printk's too much.  Drop some output.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-14 14:06:48 -07:00
Dimitri Sivanich
074b85175a vfs: fix panic in __d_lookup() with high dentry hashtable counts
When the number of dentry cache hash table entries gets too high
(2147483648 entries), as happens by default on a 16TB system, use of a
signed integer in the dcache_init() initialization loop prevents the
dentry_hashtable from getting initialized, causing a panic in
__d_lookup().  Fix this in dcache_init() and similar areas.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-02-13 20:45:38 -05:00
Linus Torvalds
e3f89f4ae4 Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1
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Merge tag 'for-linus' of git://github.com/rustyrussell/linux

* tag 'for-linus' of git://github.com/rustyrussell/linux:
  module: fix broken isapnp handling in file2alias
  module: make module param bint handle nul value
2012-02-13 16:59:53 -08:00
Dave Young
10f296cbfe module: make module param bint handle nul value
Allow bint param accept nul values, just do same as bool param.

Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-02-14 11:02:15 +10:30
Al Viro
4040153087 security: trim security.h
Trim security.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-14 10:45:42 +11:00
Al Viro
191c542442 mm: collapse security_vm_enough_memory() variants into a single function
Collapse security_vm_enough_memory() variants into a single function.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-14 10:45:39 +11:00
Thomas Meyer
47b0edcb59 tracing/trivial: Use kcalloc instead of kzalloc to allocate array
The advantage of kcalloc is, that will prevent integer overflows which could
result from the multiplication of number of elements and size and it is also
a bit nicer to read.

The semantic patch that makes this change is available
in https://lkml.org/lkml/2011/11/25/107

Link: http://lkml.kernel.org/r/1322600880.1534.347.camel@localhost.localdomain

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-13 13:48:11 -05:00
Johannes Berg
9510035849 printk/tracing: Add console output tracing
Add a printk.console trace point to record any printk
messages into the trace, regardless of the current
console loglevel. This can help correlate (existing)
printk debugging with other tracing.

Link: http://lkml.kernel.org/r/1322161388.5366.54.camel@jlt3.sipsolutions.net

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-13 13:46:05 -05:00
Rafael J. Wysocki
6f585f750d PM / Sleep: Remove unnecessary label from suspend_freeze_processes()
The Finish label in suspend_freeze_processes() is in fact unnecessary
and makes the function look more complicated than it really is, so
remove that label (along with a few empty lines).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
2012-02-13 16:26:13 +01:00
Rafael J. Wysocki
6c83b4818d PM / Sleep: Do not check wakeup too often in try_to_freeze_tasks()
Use the observation that it is more efficient to check the wakeup
variable once before the loop reporting tasks that were not
frozen in try_to_freeze_tasks() than to do that in every step of that
loop.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-13 16:26:05 +01:00
Jean Pihet
a9b542ee60 PM / QoS: unconditionally build the feature
The PM QoS feature originally didn't depend on CONFIG_PM, which was
mistakenly changed by commit e8db0be124

    PM QoS: Move and rename the implementation files

Later, commit d020283dc6

    PM / QoS: CPU C-state breakage with PM Qos change

partially fixed that by introducing a static inline definition of
pm_qos_request(), but that still didn't allow user space to use
the PM QoS interface if CONFIG_PM was unset (which had been possible
before).  For this reason, remove the dependency of PM QoS on
CONFIG_PM to make it work (as intended) with CONFIG_PM unset.

[rjw: Replaced the original changelog with a new one.]

Signed-off-by: Jean Pihet <j-pihet@ti.com>
Reported-by: Venkatesh Pallipadi <venki@google.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-13 16:23:42 +01:00
Rafael J. Wysocki
654b0c9627 Merge commit 'pm-fixes-for-3.3-rc3' into pm-qos
New material in the pm-qos branch depends on recent power management
fixes.
2012-02-13 16:20:07 +01:00
Geunsik Lim
1e42e83fde ftrace: sched_switch plugin is deprecated
Actually, sched_switch function tracer is merged into wakeup/wakeup_rt
Update 'mini-HOWTO' for ftrace(Kernel function tracer).
If we want to trace "sched:sched_switch" to trace sched_switch func,
We may utilize event option.(e.g: trace-cmd list -e | grep sched)
This patch is based on Linux-3.3.rc2-SMP-PREEMPT

Link: http://lkml.kernel.org/r/1328695537-15081-1-git-send-email-geunsik.lim@gmail.com

Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Geunsik Lim <geunsik.lim@samsung.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-13 09:14:47 -05:00
Linus Torvalds
3ec1e88b33 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Says Jens:

 "Time to push off some of the pending items.  I really wanted to wait
  until we had the regression nailed, but alas it's not quite there yet.
  But I'm very confident that it's "just" a missing expire on exit, so
  fix from Tejun should be fairly trivial.  I'm headed out for a week on
  the slopes.

  - Killing the barrier part of mtip32xx.  It doesn't really support
    barriers, and it doesn't need them (writes are fully ordered).

  - A few fixes from Dan Carpenter, preventing overflows of integer
    multiplication.

  - A fixup for loop, fixing a previous commit that didn't quite solve
    the partial read problem from Dave Young.

  - A bio integer overflow fix from Kent Overstreet.

  - Improvement/fix of the door "keep locked" part of the cdrom shared
    code from Paolo Benzini.

  - A few cfq fixes from Shaohua Li.

  - A fix for bsg sysfs warning when removing a file it did not create
    from Stanislaw Gruszka.

  - Two fixes for floppy from Vivek, preventing a crash.

  - A few block core fixes from Tejun.  One killing the over-optimized
    ioc exit path, cleaning that up nicely.  Two others fixing an oops
    on elevator switch, due to calling into the scheduler merge check
    code without holding the queue lock."

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix lockdep warning on io_context release put_io_context()
  relay: prevent integer overflow in relay_open()
  loop: zero fill bio instead of return -EIO for partial read
  bio: don't overflow in bio_get_nr_vecs()
  floppy: Fix a crash during rmmod
  floppy: Cleanup disk->queue before caling put_disk() if add_disk() was never called
  cdrom: move shared static to cdrom_device_info
  bsg: fix sysfs link remove warning
  block: don't call elevator callbacks for plug merges
  block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions
  mtip32xx: removed the irrelevant argument of mtip_hw_submit_io() and the unused member of struct driver_data
  block: strip out locking optimization in put_io_context()
  cdrom: use copy_to_user() without the underscores
  block: fix ioc locking warning
  block: fix NULL icq_cache reference
  block,cfq: change code order
2012-02-11 10:07:11 -08:00
Fernando Luis Vázquez Cao
86f5e6a7b1 watchdog: Fix code/comments mismatches
Reflect the change in the soft and hard lockup thresholds and
their relation to the frequency of the hrtimer and NMI events in
the code comments. While at it, remove references to files that
do not exist anymore.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1328827342-6253-3-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-11 15:11:33 +01:00
Linus Torvalds
ce2814f227 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix double start/stop in x86_pmu_start()
  perf evsel: Fix an issue where perf report fails to show the proper percentage
  perf tools: Fix prefix matching for kernel maps
  perf tools: Fix perf stack to non executable on x86_64
  perf: Remove deprecated WARN_ON_ONCE()
2012-02-10 09:05:07 -08:00
Dan Carpenter
f6302f1bcd relay: prevent integer overflow in relay_open()
"subbuf_size" and "n_subbufs" come from the user and they need to be
capped to prevent an integer overflow.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-10 09:04:49 +01:00
Srivatsa S. Bhat
a556d5b583 PM / Hibernate: Refactor and simplify freezer_test_done
The code related to 'freezer_test_done' is needlessly convoluted.
Refactor the code and simplify the implementation.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-09 23:56:01 +01:00
Srivatsa S. Bhat
51d6ff7acd PM / Hibernate: Thaw kernel threads in hibernation_snapshot() in error/test path
In the hibernation call path, the kernel threads are frozen inside
hibernation_snapshot(). If we happen to encounter an error further down
the road or if we are exiting early due to a successful freezer test,
then thaw kernel threads before returning to the caller.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-09 23:55:54 +01:00
Marcos Paulo de Souza
8916e3702e PM / Suspend: Avoid code duplication in suspend statistics update
The code
       if (error) {
               suspend_stats.fail++;
               dpm_save_failed_errno(error);
       } else
               suspend_stats.success++;

Appears in the kernel/power/main.c and kernel/power/suspend.c.

This patch just creates a new function to avoid duplicated code.

Suggested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Marcos Paulo de Souza <marcos.mage@gmail.com>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-09 23:55:43 +01:00
Rafael J. Wysocki
3ed3c7b559 Merge commit 'pm-fixes-for-3.3-rc3' into pm-sleep
New material in the pm-sleep branch depends on recent
power management fixes.
2012-02-09 23:54:09 +01:00
Kees Cook
1a2a4d06e1 security: create task_free security callback
The current LSM interface to cred_free is not sufficient for allowing
an LSM to track the life and death of a task. This patch adds the
task_free hook so that an LSM can clean up resources on task death.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-10 09:14:51 +11:00
Stephane Eranian
f39d47ff81 perf: Fix double start/stop in x86_pmu_start()
The following patch fixes a bug introduced by the following
commit:

        e050e3f0a7 ("perf: Fix broken interrupt rate throttling")

The patch caused the following warning to pop up depending on
the sampling frequency adjustments:

  ------------[ cut here ]------------
  WARNING: at arch/x86/kernel/cpu/perf_event.c:995 x86_pmu_start+0x79/0xd4()

It was caused by the following call sequence:

perf_adjust_freq_unthr_context.part() {
     stop()
     if (delta > 0) {
          perf_adjust_period() {
              if (period > 8*...) {
                  stop()
                  ...
                  start()
              }
          }
      }
      start()
}

Which caused a double start and a double stop, thus triggering
the assert in x86_pmu_start().

The patch fixes the problem by avoiding the double calls. We
pass a new argument to perf_adjust_period() to indicate whether
or not the event is already stopped. We can't just remove the
start/stop from that function because it's called from
__perf_event_overflow where the event needs to be reloaded via a
stop/start back-toback call.

The patch reintroduces the assertion in x86_pmu_start() which
was removed by commit:

	84f2b9b ("perf: Remove deprecated WARN_ON_ONCE()")

In this second version, we've added calls to disable/enable PMU
during unthrottling or frequency adjustment based on bug report
of spurious NMI interrupts from Eric Dumazet.

Reported-and-tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: markus@trippelsdorf.de
Cc: paulus@samba.org
Link: http://lkml.kernel.org/r/20120207133956.GA4932@quad
[ Minor edits to the changelog and to the code ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-07 16:58:56 +01:00
Tejun Heo
11a3122f6c block: strip out locking optimization in put_io_context()
put_io_context() performed a complex trylock dancing to avoid
deferring ioc release to workqueue.  It was also broken on UP because
trylock was always assumed to succeed which resulted in unbalanced
preemption count.

While there are ways to fix the UP breakage, even the most
pathological microbench (forced ioc allocation and tight fork/exit
loop) fails to show any appreciable performance benefit of the
optimization.  Strip it out.  If there turns out to be workloads which
are affected by this change, simpler optimization from the discussion
thread can be applied later.

Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <1328514611.21268.66.camel@sli10-conroe>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-07 07:51:30 +01:00
Arnaldo Carvalho de Melo
5ddf146f70 Merge branch 'perf/urgent' into perf/core
So that we can get the perf bench exec stack fixes and then apply the
remaining fix for the files added after what is in perf/urgent.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-06 19:11:02 -02:00
Linus Torvalds
23783f817b Power management fixes for 3.3-rc3
Three power management regression fixes, one for a recent regression introcuded
 by the freezer changes during the 3.3 merge window and two for regressions
 in cpuidle (resulting from PM QoS changes) and in the hibernate user space
 interface, both introduced during the 3.2 development cycle.
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Merge tag 'pm-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Power management fixes for 3.3-rc3

Three power management regression fixes, one for a recent regression introcuded
by the freezer changes during the 3.3 merge window and two for regressions
in cpuidle (resulting from PM QoS changes) and in the hibernate user space
interface, both introduced during the 3.2 development cycle.

They include:

* Two hibernate (s2disk) regression fixes from Srivatsa S. Bhat (for
 regressions introduced during the 3.3 merge window and during the 3.2
 development cycle).

* A cpuidle fix from Venki Pallipadi for a regression resulting from PM QoS
 changes during the 3.2 development cycle causing cpuidle to work incorrectly
 for CONFIG_PM unset.

* tag 'pm-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / QoS: CPU C-state breakage with PM Qos change
  PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails
  PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path
2012-02-04 15:21:39 -08:00
Srivatsa S. Bhat
379e0be812 PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails
If freezing of kernel threads fails, we are expected to automatically
thaw tasks in the error recovery path. However, at times, we encounter
situations in which we would like the automatic error recovery path
to thaw only the kernel threads, because we want to be able to do
some more cleanup before we thaw userspace. Something like:

error = freeze_kernel_threads();
if (error) {
	/* Do some cleanup */

	/* Only then thaw userspace tasks*/
	thaw_processes();
}

An example of such a situation is where we freeze/thaw filesystems
during suspend/hibernation. There, if freezing of kernel threads
fails, we would like to thaw the frozen filesystems before thawing
the userspace tasks.

So, modify freeze_kernel_threads() to thaw only kernel threads in
case of freezing failure. And change suspend_freeze_processes()
accordingly. (At the same time, let us also get rid of the rather
cryptic usage of the conditional operator (:?) in that function.)

[rjw: In fact, this patch fixes a regression introduced during the
 3.3 merge window, because without it thaw_processes() may be called
 before swsusp_free() in some situations and that may lead to massive
 memory allocation failures.]

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-04 22:23:05 +01:00
Jiang Liu
55ca6140e9 kprobes: fix a memory leak in function pre_handler_kretprobe()
In function pre_handler_kretprobe(), the allocated kretprobe_instance
object will get leaked if the entry_handler callback returns non-zero.
This may cause all the preallocated kretprobe_instance objects exhausted.

This issue can be reproduced by changing
samples/kprobes/kretprobe_example.c to probe "mutex_unlock".  And the fix
is straightforward: just put the allocated kretprobe_instance object back
onto the free_instances list.

[akpm@linux-foundation.org: use raw_spin_lock/unlock]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-03 16:16:41 -08:00
Cong Wang
2410574866 kernel/resource.c: move EXPORT_SYMBOL right after definition
EXPORT_SYMBOL(adjust_resource) should be right after adjust_resource().

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-02-03 23:37:07 +01:00
Steven Rostedt
f069686e4b tracing/softirq: Move __raise_softirq_irqoff() out of header
The __raise_softirq_irqoff() contains a tracepoint. As tracepoints in headers
can cause issues, and not to mention, bloats the kernel when they are
in a static inline, it is best to move the function that contains the
tracepoint out of the header and into softirq.c.

Link: http://lkml.kernel.org/r/20120118120711.GB14863@elte.hu

Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-03 09:48:19 -05:00
Jiri Olsa
ac483c446b ftrace: Change filter/notrace set functions to return exit code
Currently the ftrace_set_filter and ftrace_set_notrace functions
do not return any return code. So there's no way for ftrace_ops
user to tell wether the filter was correctly applied.

The set_ftrace_filter interface returns error in case the filter
did not match:

  # echo krava > set_ftrace_filter
  bash: echo: write error: Invalid argument

Changing both ftrace_set_filter and ftrace_set_notrace functions
to return zero if the filter was applied correctly or -E* values
in case of error.

Link: http://lkml.kernel.org/r/1325495060-6402-2-git-send-email-jolsa@redhat.com

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-03 09:48:18 -05:00
John Stultz
a80b83b7b8 Input: add infrastructure for selecting clockid for event time stamps
As noted by Arve and others, since wall time can jump backwards, it is
difficult to use for input because one cannot determine if one event
occurred before another or for how long a key was pressed.

However, the timestamp field is part of the kernel ABI, and cannot be
changed without possibly breaking existing users.

This patch adds a new IOCTL that allows a clockid to be set in the
evdev_client struct that will specify which time base to use for event
timestamps (ie: CLOCK_MONOTONIC instead of CLOCK_REALTIME).

For now we only support CLOCK_MONOTONIC and CLOCK_REALTIME, but
in the future we could support other clockids if appropriate.

The default remains CLOCK_REALTIME, so we don't change the ABI.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Daniel Kurtz <djkurtz@google.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2012-02-03 00:24:58 -08:00
Christopher Yeoh
8cdb878dcb Fix race in process_vm_rw_core
This fixes the race in process_vm_core found by Oleg (see

  http://article.gmane.org/gmane.linux.kernel/1235667/

for details).

This has been updated since I last sent it as the creation of the new
mm_access() function did almost exactly the same thing as parts of the
previous version of this patch did.

In order to use mm_access() even when /proc isn't enabled, we move it to
kernel/fork.c where other related process mm access functions already
are.

Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-02 12:55:17 -08:00
Linus Torvalds
2f2fde9272 Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus', 'sched-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  bugs, x86: Fix printk levels for panic, softlockups and stack dumps

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf top: Fix number of samples displayed
  perf tools: Fix strlen() bug in perf_event__synthesize_event_type()
  perf tools: Fix broken build by defining _GNU_SOURCE in Makefile
  x86/dumpstack: Remove unneeded check in dump_trace()
  perf: Fix broken interrupt rate throttling

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSW
  sched: Fix ancient race in do_exit()
  sched/nohz: Fix nohz cpu idle load balancing state with cpu hotplug
  sched/s390: Fix compile error in sched/core.c
  sched: Fix rq->nr_uninterruptible update race

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/reboot: Remove VersaLogic Menlow reboot quirk
  x86/reboot: Skip DMI checks if reboot set by user
  x86: Properly parenthesize cmpxchg() macro arguments
2012-02-02 11:11:13 -08:00
Li Zefan
761b3ef50e cgroup: remove cgroup_subsys argument from callbacks
The argument is not used at all, and it's not necessary, because
a specific callback handler of course knows which subsys it
belongs to.

Now only ->pupulate() takes this argument, because the handlers of
this callback always call cgroup_add_file()/cgroup_add_files().

So we reduce a few lines of code, though the shrinking of object size
is minimal.

 16 files changed, 113 insertions(+), 162 deletions(-)

   text    data     bss     dec     hex filename
5486240  656987 7039960 13183187         c928d3 vmlinux.o.orig
5486170  656987 7039960 13183117         c9288d vmlinux.o

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2012-02-02 09:20:22 -08:00
Srivatsa S. Bhat
fe9161db2e PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path
In the SNAPSHOT_CREATE_IMAGE ioctl, if the call to hibernation_snapshot()
fails, the frozen tasks are not thawed.

And in the case of success, if we happen to exit due to a successful freezer
test, all tasks (including those of userspace) are thawed, whereas actually
we should have thawed only the kernel threads at that point. Fix both these
issues.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: stable@vger.kernel.org
2012-02-01 22:16:36 +01:00
Hiroshi Shimamoto
ed387b781e sched: Move SMP-only variable into the SMP section
This also fixes the following compilation warning on !SMP:

  CC kernel/sched/fair.o
  kernel/sched/fair.c:218:36: warning: 'max_load_balance_interval' defined but not used [-Wunused-variable]

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4F2754A0.9090306@ct.jp.nec.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-31 13:40:59 +01:00
Ingo Molnar
bb1693f89a Merge branch 'perf/urgent' into perf/core
We cherry-picked 3 commits into perf/urgent, merge them back to allow
conflict-free work on those files.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-31 13:02:37 +01:00
Mandeep Singh Baines
61d1d219c4 cgroup: remove extra calls to find_existing_css_set
In cgroup_attach_proc, we indirectly call find_existing_css_set 3
times. It is an expensive call so we want to call it a minimum
of times. This patch only calls it once and stores the result so
that it can be used later on when we call cgroup_task_migrate.

This required modifying cgroup_task_migrate to take the new css_set
(which we obtained from find_css_set) as a parameter. The nice side
effect of this is that cgroup_task_migrate is now identical for
cgroup_attach_task and cgroup_attach_proc. It also now returns a
void since it can never fail.

Changes in V5:
* https://lkml.org/lkml/2012/1/20/344 (Tejun Heo)
  * Remove css_set_refs
Changes in V4:
* https://lkml.org/lkml/2011/12/22/421 (Li Zefan)
  * Avoid GFP_KERNEL (sleep) in rcu_read_lock by getting css_set in
    a separate loop not under an rcu_read_lock
Changes in V3:
* https://lkml.org/lkml/2011/12/22/13 (Li Zefan)
  * Fixed earlier bug by creating a seperate patch to remove tasklist_lock
Changes in V2:
* https://lkml.org/lkml/2011/12/20/372 (Tejun Heo)
  * Move find_css_set call into loop which creates the flex array
* Author
  * Kill css_set_refs and use group_size instead
  * Fix an off-by-one error in counting css_set refs
  * Add a retval check in out_list_teardown

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: containers@lists.linux-foundation.org
Cc: cgroups@vger.kernel.org
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Menage <paul@paulmenage.org>
2012-01-30 13:01:39 -08:00
Alex Frid
d031e1de2c PM / QoS: Simplify PM QoS expansion/merge
- Replace class ID #define with enumeration
 - Loop through PM QoS objects during initialization (rather than
   initializing them one-by-one)

Signed-off-by: Alex Frid <afrid@nvidia.com>
Reviewed-by: Antti Miettinen <amiettinen@nvidia.com>
Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com>
Reviewed-by: Scott Williams <scwilliams@nvidia.com>
Reviewed-by: Yu-Huan Hsu <yhsu@nvidia.com>
Acked-by: markgross <markgross@thegnar.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-29 20:39:25 +01:00
Rafael J. Wysocki
cf579dfb82 PM / Sleep: Introduce "late suspend" and "early resume" of devices
The current device suspend/resume phases during system-wide power
transitions appear to be insufficient for some platforms that want
to use the same callback routines for saving device states and
related operations during runtime suspend/resume as well as during
system suspend/resume.  In principle, they could point their
.suspend_noirq() and .resume_noirq() to the same callback routines
as their .runtime_suspend() and .runtime_resume(), respectively,
but at least some of them require device interrupts to be enabled
while the code in those routines is running.

It also makes sense to have device suspend-resume callbacks that will
be executed with runtime PM disabled and with device interrupts
enabled in case someone needs to run some special code in that
context during system-wide power transitions.

Apart from this, .suspend_noirq() and .resume_noirq() were introduced
as a workaround for drivers using shared interrupts and failing to
prevent their interrupt handlers from accessing suspended hardware.
It appears to be better not to use them for other porposes, or we may
have to deal with some serious confusion (which seems to be happening
already).

For the above reasons, introduce new device suspend/resume phases,
"late suspend" and "early resume" (and analogously for hibernation)
whose callback will be executed with runtime PM disabled and with
device interrupts enabled and whose callback pointers generally may
point to runtime suspend/resume routines.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-01-29 20:38:29 +01:00
Rafael J. Wysocki
181e9bdef3 PM / Hibernate: Fix s2disk regression related to freezing workqueues
Commit 2aede851dd

  PM / Hibernate: Freeze kernel threads after preallocating memory

introduced a mechanism by which kernel threads were frozen after
the preallocation of hibernate image memory to avoid problems with
frozen kernel threads not responding to memory freeing requests.
However, it overlooked the s2disk code path in which the
SNAPSHOT_CREATE_IMAGE ioctl was run directly after SNAPSHOT_FREE,
which caused freeze_workqueues_begin() to BUG(), because it saw
that worqueues had been already frozen.

Although in principle this issue might be addressed by removing
the relevant BUG_ON() from freeze_workqueues_begin(), that would
reintroduce the very problem that commit 2aede851dd
attempted to avoid into that particular code path.  For this reason,
to fix the issue at hand, introduce thaw_kernel_threads() and make
the SNAPSHOT_FREE ioctl execute it.

Special thanks to Srivatsa S. Bhat for detailed analysis of the
problem.

Reported-and-tested-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: stable@kernel.org
2012-01-29 20:35:52 +01:00
Rakib Mullick
30fd049afc sched: Remove sched_switch
Currently we don't utilize the sched_switch field anymore.

But, simply removing sched_switch field from the middle of the
sched_stat output will break tools.

So, to stay compatible we hardcode it to zero and remove the
field from the scheduler data structures.

Update the schedstat documentation accordingly.

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1327422836.27181.5.camel@localhost.localdomain
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-27 13:28:53 +01:00
Vincent Guittot
4ec4412e1e sched: Ensure cpu_power periodic update
With a lot of small tasks, the softirq sched is nearly never called
when no_hz is enabled. In this case load_balance() is mainly called
with the newly_idle mode which doesn't update the cpu_power.

Add a next_update field which ensure a maximum update period when
there is short activity.

Having stale cpu_power information can skew the load-balancing
decisions, this is cured by the guaranteed update.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1323717668-2143-1-git-send-email-vincent.guittot@linaro.org
2012-01-27 13:28:49 +01:00
Peter Zijlstra
39be350127 sched, block: Unify cache detection
The block layer has some code trying to determine if two CPUs share a
cache, the scheduler has a similar function. Expose the function used
by the scheduler and make the block layer use it, thereby removing the
block layers usage of CONFIG_SCHED* and topology bits.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jens Axboe <axboe@kernel.dk>
Link: http://lkml.kernel.org/r/1327579450.2446.95.camel@twins
2012-01-27 13:28:48 +01:00
Chanho Min
cb297a3e43 sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSW
This issue happens under the following conditions:

 1. preemption is off
 2. __ARCH_WANT_INTERRUPTS_ON_CTXSW is defined
 3. RT scheduling class
 4. SMP system

Sequence is as follows:

 1.suppose current task is A. start schedule()
 2.task A is enqueued pushable task at the entry of schedule()
   __schedule
    prev = rq->curr;
    ...
    put_prev_task
     put_prev_task_rt
      enqueue_pushable_task
 4.pick the task B as next task.
   next = pick_next_task(rq);
 3.rq->curr set to task B and context_switch is started.
   rq->curr = next;
 4.At the entry of context_swtich, release this cpu's rq->lock.
   context_switch
    prepare_task_switch
     prepare_lock_switch
      raw_spin_unlock_irq(&rq->lock);
 5.Shortly after rq->lock is released, interrupt is occurred and start IRQ context
 6.try_to_wake_up() which called by ISR acquires rq->lock
    try_to_wake_up
     ttwu_remote
      rq = __task_rq_lock(p)
      ttwu_do_wakeup(rq, p, wake_flags);
        task_woken_rt
 7.push_rt_task picks the task A which is enqueued before.
   task_woken_rt
    push_rt_tasks(rq)
     next_task = pick_next_pushable_task(rq)
 8.At find_lock_lowest_rq(), If double_lock_balance() returns 0,
   lowest_rq can be the remote rq.
  (But,If preemption is on, double_lock_balance always return 1 and it
   does't happen.)
   push_rt_task
    find_lock_lowest_rq
     if (double_lock_balance(rq, lowest_rq))..
 9.find_lock_lowest_rq return the available rq. task A is migrated to
   the remote cpu/rq.
   push_rt_task
    ...
    deactivate_task(rq, next_task, 0);
    set_task_cpu(next_task, lowest_rq->cpu);
    activate_task(lowest_rq, next_task, 0);
 10. But, task A is on irq context at this cpu.
     So, task A is scheduled by two cpus at the same time until restore from IRQ.
     Task A's stack is corrupted.

To fix it, don't migrate an RT task if it's still running.

Signed-off-by: Chanho Min <chanho.min@lge.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/CAOAMb1BHA=5fm7KTewYyke6u-8DP0iUuJMpgQw54vNeXFsGpoQ@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-27 12:49:41 +01:00
Ingo Molnar
44a6839711 Merge branch 'perf/fast' into perf/core
Merge reason: Lets ready it for v3.4

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-27 12:08:09 +01:00
Stephane Eranian
e050e3f0a7 perf: Fix broken interrupt rate throttling
This patch fixes the sampling interrupt throttling mechanism.

It was broken in v3.2. Events were not being unthrottled. The
unthrottling mechanism required that events be checked at each
timer tick.

This patch solves this problem and also separates:

  - unthrottling
  - multiplexing
  - frequency-mode period adjustments

Not all of them need to be executed at each timer tick.

This third version of the patch is based on my original patch +
PeterZ proposal (https://lkml.org/lkml/2012/1/7/87).

At each timer tick, for each context:

  - if the current CPU has throttled events, we unthrottle events

  - if context has frequency-based events, we adjust sampling periods

  - if we have reached the jiffies interval, we multiplex (rotate)

We decoupled rotation (multiplexing) from frequency-mode sampling
period adjustments.  They should not necessarily happen at the same
rate. Multiplexing is subject to jiffies_interval (currently at 1
but could be higher once the tunable is exposed via sysfs).

We have grouped frequency-mode adjustment and unthrottling into the
same routine to minimize code duplication. When throttled while in
frequency mode, we scan the events only once.

We have fixed the threshold enforcement code in __perf_event_overflow().
There was a bug whereby it would allow more than the authorized rate
because an increment of hwc->interrupts was not executed at the right
place.

The patch was tested with low sampling limit (2000) and fixed periods,
frequency mode, overcommitted PMU.

On a 2.1GHz AMD CPU:

 $ cat /proc/sys/kernel/perf_event_max_sample_rate
 2000

We set a rate of 3000 samples/sec (2.1GHz/3000 = 700000):

 $ perf record -e cycles,cycles -c 700000  noploop 10
 $ perf report -D | tail -21

 Aggregated stats:
           TOTAL events:      80086
            MMAP events:         88
            COMM events:          2
            EXIT events:          4
        THROTTLE events:      19996
      UNTHROTTLE events:      19996
          SAMPLE events:      40000

 cycles stats:
           TOTAL events:      40006
            MMAP events:          5
            COMM events:          1
            EXIT events:          4
        THROTTLE events:       9998
      UNTHROTTLE events:       9998
          SAMPLE events:      20000

 cycles stats:
           TOTAL events:      39996
        THROTTLE events:       9998
      UNTHROTTLE events:       9998
          SAMPLE events:      20000

For 10s, the cap is 2x2000x10 = 40000 samples.
We get exactly that: 20000 samples/event.

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: <stable@kernel.org> # v3.2+
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120126160319.GA5655@quad
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-27 12:06:39 +01:00
Ingo Molnar
801493c2e2 Merge branch 'linus' into perf/core
Merge reason: pick up fixes that are upstream, we need them
              because we'll apply dependent patches.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-27 12:01:43 +01:00
Yasunori Goto
b5740f4b2c sched: Fix ancient race in do_exit()
try_to_wake_up() has a problem which may change status from TASK_DEAD to
TASK_RUNNING in race condition with SMI or guest environment of virtual
machine. As a result, exited task is scheduled() again and panic occurs.

Here is the sequence how it occurs:

 ----------------------------------+-----------------------------
                                   |
            CPU A                  |             CPU B
 ----------------------------------+-----------------------------

TASK A calls exit()....

do_exit()

  exit_mm()
    down_read(mm->mmap_sem);

    rwsem_down_failed_common()

      set TASK_UNINTERRUPTIBLE
      set waiter.task <= task A
      list_add to sem->wait_list
           :
      raw_spin_unlock_irq()
      (I/O interruption occured)

                                      __rwsem_do_wake(mmap_sem)

                                        list_del(&waiter->list);
                                        waiter->task = NULL
                                        wake_up_process(task A)
                                          try_to_wake_up()
                                             (task is still
                                               TASK_UNINTERRUPTIBLE)
                                              p->on_rq is still 1.)

                                              ttwu_do_wakeup()
                                                 (*A)
                                                   :
     (I/O interruption handler finished)

      if (!waiter.task)
          schedule() is not called
          due to waiter.task is NULL.

      tsk->state = TASK_RUNNING

          :
                                              check_preempt_curr();
                                                  :
  task->state = TASK_DEAD
                                              (*B)
                                        <---    set TASK_RUNNING (*C)

     schedule()
     (exit task is running again)
     BUG_ON() is called!
 --------------------------------------------------------

The execution time between (*A) and (*B) is usually very short,
because the interruption is disabled, and setting TASK_RUNNING at (*C)
must be executed before setting TASK_DEAD.

HOWEVER, if SMI is interrupted between (*A) and (*B),
(*C) is able to execute AFTER setting TASK_DEAD!
Then, exited task is scheduled again, and BUG_ON() is called....

If the system works on guest system of virtual machine, the time
between (*A) and (*B) may be also long due to scheduling of hypervisor,
and same phenomenon can occur.

By this patch, do_exit() waits for releasing task->pi_lock which is used
in try_to_wake_up(). It guarantees the task becomes TASK_DEAD after
waking up.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20120117174031.3118.E1E9C6FF@jp.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-27 11:55:36 +01:00
Thomas Gleixner
cc06268c6a time: Move common updates to a function
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:31 -08:00
Thomas Gleixner
058892e632 time: Reorder so the hot data is together
Keep all the interesting data in a single cache line.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:29 -08:00
John Stultz
92c1d3ed4d time: Remove most of xtime_lock usage in timekeeping.c
Now that ntp.c's locking is reworked, we can remove most
of the xtime_lock usage in timekeeping.c

The remaining xtime_lock presence is really for jiffies access
and the global load calculation.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:27 -08:00
John Stultz
bd3312681f ntp: Add ntp_lock to replace xtime_locking
Use a ntp_lock spin lock to replace xtime_lock locking in ntp.c

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:25 -08:00
John Stultz
ea7cf49a76 ntp: Access tick_length variable via ntp_tick_length()
Currently the NTP managed tick_length value is accessed globally,
in preparations for locking cleanups, make sure it is accessed via
a function and mark it as static.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:23 -08:00
John Stultz
8357929e6a ntp: Cleanup timex.h
Move ntp_sycned to ntp.c and mark time_status as static.
Also yank function declaration for non-existant function.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:20 -08:00
John Stultz
70471f2f06 time: Add timekeeper lock
Now that all the timekeeping variables are stored in
the timekeeper structure, add a new lock to protect the
structure.

For now, this lock nests under the xtime_lock for writes.

For readers, we don't need to take xtime_lock anymore.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:18 -08:00
John Stultz
8fcce546be time: Cleanup global variables and move them to the top
Move global xtime_lock and timekeeping_suspended values up
to the top of timekeeping.c

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:16 -08:00
John Stultz
01f71b47e0 time: Move raw_time into timekeeper structure
In preparation for locking cleanups, move raw_time into
timekeeper structure.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:14 -08:00
John Stultz
8ff2cb92dd time: Move xtime into timekeeeper structure
In preparation for locking cleanups, move xtime into
timekeeper structure.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:12 -08:00
John Stultz
d9f7217aac time: Move wall_to_monotonic into the timekeeper structure
In preparation for locking cleanups, move wall_to_monotonic
into the timekeeper structure.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:09 -08:00
John Stultz
00c5fb774e time: Move total_sleep_time into the timekeeper structure
Move total_sleep_time into the timekeeper structure in preparation
for locking cleanups

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-01-26 19:44:07 -08:00
Linus Torvalds
b57cea5e33 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Call perf_cgroup_event_time() directly
  perf: Don't call release_callchain_buffers() if allocation fails
2012-01-26 12:45:57 -08:00
Linus Torvalds
2437dcbf55 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Add missing __cpuinit annotation in rcutorture code
  sched: Add "const" to is_idle_task() parameter
  rcu: Make rcutorture bool parameters really bool (core code)
  memblock: Fix alloc failure due to dumb underflow protection in memblock_find_in_range_node()
2012-01-26 12:45:41 -08:00
Prarit Bhargava
b0f4c4b32c bugs, x86: Fix printk levels for panic, softlockups and stack dumps
rsyslog will display KERN_EMERG messages on a connected
terminal.  However, these messages are useless/undecipherable
for a general user.

For example, after a softlockup we get:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Stack:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Call Trace:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Code: ff ff a8 08 75 25 31 d2 48 8d 86 38 e0 ff ff 48 89
 d1 0f 01 c8 0f ae f0 48 8b 86 38 e0 ff ff a8 08 75 08 b1 01 4c 89 e0 0f 01 c9 <e8> ea 69 dd ff 4c 29 e8 48 89 c7 e8 0f bc da ff 49 89 c4 49 89

This happens because the printk levels for these messages are
incorrect. Only an informational message should be displayed on
a terminal.

I modified the printk levels for various messages in the kernel
and tested the output by using the drivers/misc/lkdtm.c kernel
modules (ie, softlockups, panics, hard lockups, etc.) and
confirmed that the console output was still the same and that
the output to the terminals was correct.

For example, in the case of a softlockup we now see the much
more informative:

 Message from syslogd@intel-s3e37-04 at Jan 25 10:18:06 ...
 BUG: soft lockup - CPU4 stuck for 60s!

instead of the above confusing messages.

AFAICT, the messages no longer have to be KERN_EMERG.  In the
most important case of a panic we set console_verbose().  As for
the other less severe cases the correct data is output to the
console and /var/log/messages.

Successfully tested by me using the drivers/misc/lkdtm.c module.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: dzickus@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1327586134-11926-1-git-send-email-prarit@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 21:28:45 +01:00
Suresh Siddha
71325960d1 sched/nohz: Fix nohz cpu idle load balancing state with cpu hotplug
With the recent nohz scheduler changes, rq's nohz flag
'NOHZ_TICK_STOPPED' and its associated state doesn't get cleared
immediately after the cpu exits idle. This gets cleared as part
of the next tick seen on that cpu.

For the cpu offline support, we need to clear this state
manually. Fix it by registering a cpu notifier, which clears the
nohz idle load balance state for this rq explicitly during the
CPU_DYING notification.

There won't be any nohz updates for that cpu, after the
CPU_DYING notification. But lets be extra paranoid and skip
updating the nohz state in the select_nohz_load_balancer() if
the cpu is not in active state anymore.

Reported-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Reviewed-and-tested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1327026538.16150.40.camel@sbsiddha-desk.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 19:38:13 +01:00
Christian Borntraeger
db7e527da4 sched/s390: Fix compile error in sched/core.c
Commit 029632fbb7 ("sched: Make
separate sched*.c translation units") removed the include of
asm/mutex.h from sched.c.

This breaks the combination of:

 CONFIG_MUTEX_SPIN_ON_OWNER=yes
 CONFIG_HAVE_ARCH_MUTEX_CPU_RELAX=yes

like s390 without mutex debugging:

  CC      kernel/sched/core.o
  kernel/sched/core.c: In function ‘mutex_spin_on_owner’:
  kernel/sched/core.c:3287: error: implicit declaration of function ‘arch_mutex_cpu_relax’

Lets re-add the include to kernel/sched/core.c

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1326268696-30904-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 19:38:11 +01:00
Peter Zijlstra
4ca9b72b71 sched: Fix rq->nr_uninterruptible update race
KOSAKI Motohiro noticed the following race:

 > CPU0                    CPU1
 > --------------------------------------------------------
 > deactivate_task()
 >                         task->state = TASK_UNINTERRUPTIBLE;
 > activate_task()
 >    rq->nr_uninterruptible--;
 >
 >                         schedule()
 >                           deactivate_task()
 >                             rq->nr_uninterruptible++;
 >

Kosaki-San's scenario is possible when CPU0 runs
__sched_setscheduler() against CPU1's current @task.

__sched_setscheduler() does a dequeue/enqueue in order to move
the task to its new queue (position) to reflect the newly provided
scheduling parameters. However it should be completely invariant to
nr_uninterruptible accounting, sched_setscheduler() doesn't affect
readyness to run, merely policy on when to run.

So convert the inappropriate activate/deactivate_task usage to
enqueue/dequeue_task, which avoids the nr_uninterruptible accounting.

Also convert the two other sites: __migrate_task() and
normalize_task() that still use activate/deactivate_task. These sites
aren't really a problem since __migrate_task() will only be called on
non-running task (and therefore are immume to the described problem)
and normalize_task() isn't ever used on regular systems.

Also remove the comments from activate/deactivate_task since they're
misleading at best.

Reported-by: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1327486224.2614.45.camel@laptop
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 19:38:09 +01:00
Ingo Molnar
96070c83b2 Merge branch 'sigtrace' of git://github.com/utrace/linux into perf/core 2012-01-26 11:09:19 +01:00
Rob Herring
2ed86b16ea irq: make SPARSE_IRQ an optionally hidden option
On ARM, we don't want SPARSE_IRQ to be a user visible option. Make
SPARSE_IRQ visible based on MAY_HAVE_SPARSE_IRQ instead of depending
on HAVE_SPARSE_IRQ.

With this, SPARSE_IRQ is not visible on C6X and ARM.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-sh@vger.kernel.org
2012-01-25 20:37:42 -06:00
Eric W. Biederman
1f87f0b52b sysctl: Move the implementation into fs/proc/proc_sysctl.c
Move the core sysctl code from kernel/sysctl.c and kernel/sysctl_check.c
into fs/proc/proc_sysctl.c.

Currently sysctl maintenance is hampered by the sysctl implementation
being split across 3 files with artificial layering between them.
Consolidate the entire sysctl implementation into 1 file so that
it is easier to see what is going on and hopefully allowing for
simpler maintenance.

For functions that are now only used in fs/proc/proc_sysctl.c remove
their declarations from sysctl.h and make them static in fs/proc/proc_sysctl.c

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-01-24 16:37:54 -08:00
Eric W. Biederman
de4e83bd6b sysctl: Register the base sysctl table like any other sysctl table.
Simplify the code by treating the base sysctl table like any other
sysctl table and register it with register_sysctl_table.

To ensure this table is registered early enough to avoid problems
call sysctl_init from proc_sys_init.

Rename sysctl_net.c:sysctl_init() to net_sysctl_init() to avoid
name conflicts now that kernel/sysctl.c:sysctl_init() is no longer
static.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-01-24 16:37:54 -08:00
Eric W. Biederman
0ce8974d50 sysctl: Consolidate !CONFIG_SYSCTL handling
- In sysctl.h move functions only available if CONFIG_SYSCL
  is defined inside of #ifdef CONFIG_SYSCTL

- Move the stub function definitions for !CONFIG_SYSCTL
  into sysctl.h and make them static inlines.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-01-24 16:37:54 -08:00
Linus Torvalds
701b259f44 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Davem says:

1) Fix JIT code generation on x86-64 for divide by zero, from Eric Dumazet.

2) tg3 header length computation correction from Eric Dumazet.

3) More build and reference counting fixes for socket memory cgroup
   code from Glauber Costa.

4) module.h snuck back into a core header after all the hard work we
   did to remove that, from Paul Gortmaker and Jesper Dangaard Brouer.

5) Fix PHY naming regression and add some new PCI IDs in stmmac, from
   Alessandro Rubini.

6) Netlink message generation fix in new team driver, should only advertise
   the entries that changed during events, from Jiri Pirko.

7) SRIOV VF registration and unregistration fixes, and also add a
   missing PCI ID, from Roopa Prabhu.

8) Fix infinite loop in tx queue flush code of brcmsmac, from Stanislaw Gruszka.

9) ftgmac100/ftmac100 build fix, missing interrupt.h include.

10) Memory leak fix in net/hyperv do_set_mutlicast() handling, from Wei Yongjun.

11) Off by one fix in netem packet scheduler, from Vijay Subramanian.

12) TCP loss detection fix from Yuchung Cheng.

13) TCP reset packet MD5 calculation uses wrong address, fix from Shawn Lu.

14) skge carrier assertion and DMA mapping fixes from Stephen Hemminger.

15) Congestion recovery undo performed at the wrong spot in BIC and CUBIC
    congestion control modules, fix from Neal Cardwell.

16) Ethtool ETHTOOL_GSSET_INFO is unnecessarily restrictive, from Michał Mirosław.

17) Fix triggerable race in ipv6 sysctl handling, from Francesco Ruggeri.

18) Statistics bug fixes in mlx4 from Eugenia Emantayev.

19) rds locking bug fix during info dumps, from your's truly.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (67 commits)
  rds: Make rds_sock_lock BH rather than IRQ safe.
  netprio_cgroup.h: dont include module.h from other includes
  net: flow_dissector.c missing include linux/export.h
  team: send only changed options/ports via netlink
  net/hyperv: fix possible memory leak in do_set_multicast()
  drivers/net: dsa/mv88e6xxx.c files need linux/module.h
  stmmac: added PCI identifiers
  llc: Fix race condition in llc_ui_recvmsg
  stmmac: fix phy naming inconsistency
  dsa: Add reporting of silicon revision for Marvell 88E6123/88E6161/88E6165 switches.
  tg3: fix ipv6 header length computation
  skge: add byte queue limit support
  mv643xx_eth: Add Rx Discard and Rx Overrun statistics
  bnx2x: fix compilation error with SOE in fw_dump
  bnx2x: handle CHIP_REVISION during init_one
  bnx2x: allow user to change ring size in ISCSI SD mode
  bnx2x: fix Big-Endianess in ethtool -t
  bnx2x: fixed ethtool statistics for MF modes
  bnx2x: credit-leakage fixup on vlan_mac_del_all
  macvlan: fix a possible use after free
  ...
2012-01-24 15:51:40 -08:00
Linus Torvalds
ac1e3d4f5c Power management fixes for 3.3
Two fixes for regressions introduced during the merge window, one fix for
 a long-standing obscure issue in the computation of hibernate image size
 and two small PM documentation fixes.
 
 Namhyung Kim (1):
       PM / Hibernate: Correct additional pages number calculation
 
 Srivatsa S. Bhat (1):
       PM / Hibernate: Rewrite unlock_system_sleep() to fix s2disk regression
 
 Tetsuo Handa (1):
       PM / Sleep: Fix read_unlock_usermodehelper() call.
 
 Viresh Kumar (2):
       PM / Documentation: Fix spelling mistake in basic-pm-debugging.txt
       PM / Documentation: Fix minor issue in freezing_of_tasks.txt
 
  Documentation/power/basic-pm-debugging.txt |    2 +-
  Documentation/power/freezing-of-tasks.txt  |    8 ++++----
  drivers/base/firmware_class.c              |    3 +--
  include/linux/suspend.h                    |   19 +++++++++++++++++--
  kernel/power/snapshot.c                    |    3 ++-
  5 files changed, 25 insertions(+), 10 deletions(-)
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Merge tag 'pm-fixes-for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Power management fixes for 3.3

Two fixes for regressions introduced during the merge window, one fix for
a long-standing obscure issue in the computation of hibernate image size
and two small PM documentation fixes.

* tag 'pm-fixes-for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / Sleep: Fix read_unlock_usermodehelper() call.
  PM / Hibernate: Rewrite unlock_system_sleep() to fix s2disk regression
  PM / Hibernate: Correct additional pages number calculation
  PM / Documentation: Fix minor issue in freezing_of_tasks.txt
  PM / Documentation: Fix spelling mistake in basic-pm-debugging.txt
2012-01-23 15:11:27 -08:00
Linus Torvalds
a99cbf6b43 Merge branch 'kernel-doc' from Randy Dunlap
The usual kernel-doc fixups from Randy.  Some of them David acked as
merged in his tree, this is the random left-overs.

* kernel-doc:
  docbook: fix sched source file names in device-drivers book
  docbook: change iomap source filename in deviceiobook
  docbook: don't use serial_core.h in device-drivers book
  kernel-doc: fix kernel-doc warnings in sched
  kernel-doc: fix new warnings in cfg80211.h
  kernel-doc: fix new warning in usb.h
  kernel-doc: fix new warnings in device.h
  kernel-doc: fix new warnings in debugfs
  kernel-doc: fix new warning in regulator core
  kernel-doc: fix new warnings in pci
  kernel-doc: fix new warnings in driver-core
  kernel-doc: fix new warnings in auditsc.c
  scripts/kernel-doc: fix fatal error caused by cfg80211.h
2012-01-23 10:08:08 -08:00
Randy Dunlap
fa757281a0 kernel-doc: fix kernel-doc warnings in sched
Fix new kernel-doc notation warnings:

Warning(include/linux/sched.h:2094): No description found for parameter 'p'
Warning(include/linux/sched.h:2094): Excess function parameter 'tsk' description in 'is_idle_task'
Warning(kernel/sched/cpupri.c:139): No description found for parameter 'newpri'
Warning(kernel/sched/cpupri.c:139): Excess function parameter 'pri' description in 'cpupri_set'
Warning(kernel/sched/cpupri.c:208): Excess function parameter 'bootmem' description in 'cpupri_init'

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc:	Ingo Molnar <mingo@elte.hu>
Cc:	Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-23 08:44:54 -08:00
Randy Dunlap
42ae610c1a kernel-doc: fix new warnings in auditsc.c
Fix new kernel-doc warnings in auditsc.c:

Warning(kernel/auditsc.c:1875): No description found for parameter 'success'
Warning(kernel/auditsc.c:1875): No description found for parameter 'return_code'
Warning(kernel/auditsc.c:1875): Excess function parameter 'pt_regs' description in '__audit_syscall_exit'

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-23 08:44:53 -08:00
Ananth N Mavinakayanahalli
d496aab567 kprobes: initialize before using a hlist
Commit ef53d9c5e ("kprobes: improve kretprobe scalability with hashed
locking") introduced a bug where we can potentially leak
kretprobe_instances since we initialize a hlist head after having used
it.

Initialize the hlist head before using it.

Reported by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srinivasa D S <srinivasa@in.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-23 08:38:48 -08:00
Glauber Costa
0e90b31f4b net: introduce res_counter_charge_nofail() for socket allocations
There is a case in __sk_mem_schedule(), where an allocation
is beyond the maximum, but yet we are allowed to proceed.
It happens under the following condition:

	sk->sk_wmem_queued + size >= sk->sk_sndbuf

The network code won't revert the allocation in this case,
meaning that at some point later it'll try to do it. Since
this is never communicated to the underlying res_counter
code, there is an inbalance in res_counter uncharge operation.

I see two ways of fixing this:

1) storing the information about those allocations somewhere
   in memcg, and then deducting from that first, before
   we start draining the res_counter,
2) providing a slightly different allocation function for
   the res_counter, that matches the original behavior of
   the network code more closely.

I decided to go for #2 here, believing it to be more elegant,
since #1 would require us to do basically that, but in a more
obscure way.

Signed-off-by: Glauber Costa <glommer@parallels.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
CC: Tejun Heo <tj@kernel.org>
CC: Li Zefan <lizf@cn.fujitsu.com>
CC: Laurent Chavey <chavey@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-22 15:08:46 -05:00
Namhyung Kim
46cd6a7f68 perf: Call perf_cgroup_event_time() directly
The perf_event_time() will call perf_cgroup_event_time()
if @event is a cgroup event. Just do it directly and avoid
the extra check..

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Link: http://lkml.kernel.org/r/1327021966-27688-2-git-send-email-namhyung.kim@lge.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-21 09:33:42 +01:00
Namhyung Kim
fd45c15f13 perf: Don't call release_callchain_buffers() if allocation fails
When alloc_callchain_buffers() fails, it frees all of
entries before return. In addition, calling the
release_callchain_buffers() will cause a NULL pointer
dereference since callchain_cpu_entries is not set.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Link: http://lkml.kernel.org/r/1327021966-27688-1-git-send-email-namhyung.kim@lge.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-21 09:33:41 +01:00
Mandeep Singh Baines
fb5d2b4cfc cgroup: replace tasklist_lock with rcu_read_lock
We can replace the tasklist_lock in cgroup_attach_proc with an
rcu_read_lock().

Changes in V4:
* https://lkml.org/lkml/2011/12/23/284 (Frederic Weisbecker)
  * Minimize size of rcu_read_lock critical section
  * Add comment
* https://lkml.org/lkml/2011/12/26/136 (Li Zefan)
  * Split into two patches
Changes in V3:
* https://lkml.org/lkml/2011/12/22/419 (Frederic Weisbecker)
  * Add an rcu_read_lock to protect against exit
Changes in V2:
* https://lkml.org/lkml/2011/12/22/86 (Tejun Heo)
  * Use a goto instead of returning -EAGAIN

Suggested-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: containers@lists.linux-foundation.org
Cc: cgroups@vger.kernel.org
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Menage <paul@paulmenage.org>
2012-01-20 15:58:13 -08:00
Mandeep Singh Baines
b78949ebfb cgroup: simplify double-check locking in cgroup_attach_proc
To keep the complexity of the double-check locking in one place, move
the thread_group_leader check up into attach_task_by_pid().  This
allows us to use a goto instead of returning -EAGAIN.

While at it, convert a couple of returns to gotos and use rcu for the
!pid case also in order to simplify the logic.

Changes in V2:
* https://lkml.org/lkml/2011/12/22/86 (Tejun Heo)
  * Use a goto instead of returning -EAGAIN

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: containers@lists.linux-foundation.org
Cc: cgroups@vger.kernel.org
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Menage <paul@paulmenage.org>
2012-01-20 15:58:13 -08:00
Li Zefan
245282557c cgroup: move struct cgroup_pidlist out from the header file
It's internally used only.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2012-01-20 09:30:08 -08:00
Linus Torvalds
567e47935a Merge branches 'sched-urgent-for-linus', 'perf-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/accounting, proc: Fix /proc/stat interrupts sum

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tracepoints/module: Fix disabling tracepoints with taint CRAP or OOT
  x86/kprobes: Add arch/x86/tools/insn_sanity to .gitignore
  x86/kprobes: Fix typo transferred from Intel manual

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, syscall: Need __ARCH_WANT_SYS_IPC for 32 bits
  x86, tsc: Fix SMI induced variation in quick_pit_calibrate()
  x86, opcode: ANDN and Group 17 in x86-opcode-map.txt
  x86/kconfig: Move the ZONE_DMA entry under a menu
  x86/UV2: Add accounting for BAU strong nacks
  x86/UV2: Ack BAU interrupt earlier
  x86/UV2: Remove stale no-resources test for UV2 BAU
  x86/UV2: Work around BAU bug
  x86/UV2: Fix BAU destination timeout initialization
  x86/UV2: Fix new UV2 hardware by using native UV2 broadcast mode
  x86: Get rid of dubious one-bit signed bitfield
2012-01-19 14:53:06 -08:00
Namhyung Kim
160cb5a97d PM / Hibernate: Correct additional pages number calculation
The struct bm_block is allocated by chain_alloc(),
so it'd better counting it in LINKED_PAGE_DATA_SIZE.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-19 23:23:10 +01:00
Linus Torvalds
f429ee3b80 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit: (29 commits)
  audit: no leading space in audit_log_d_path prefix
  audit: treat s_id as an untrusted string
  audit: fix signedness bug in audit_log_execve_info()
  audit: comparison on interprocess fields
  audit: implement all object interfield comparisons
  audit: allow interfield comparison between gid and ogid
  audit: complex interfield comparison helper
  audit: allow interfield comparison in audit rules
  Kernel: Audit Support For The ARM Platform
  audit: do not call audit_getname on error
  audit: only allow tasks to set their loginuid if it is -1
  audit: remove task argument to audit_set_loginuid
  audit: allow audit matching on inode gid
  audit: allow matching on obj_uid
  audit: remove audit_finish_fork as it can't be called
  audit: reject entry,always rules
  audit: inline audit_free to simplify the look of generic code
  audit: drop audit_set_macxattr as it doesn't do anything
  audit: inline checks for not needing to collect aux records
  audit: drop some potentially inadvisable likely notations
  ...

Use evil merge to fix up grammar mistakes in Kconfig file.

Bad speling and horrible grammar (and copious swearing) is to be
expected, but let's keep it to commit messages and comments, rather than
expose it to users in config help texts or printouts.
2012-01-17 16:41:31 -08:00
Kees Cook
c158a35c8a audit: no leading space in audit_log_d_path prefix
audit_log_d_path() injects an additional space before the prefix,
which serves no purpose and doesn't mix well with other audit_log*()
functions that do not sneak extra characters into the log.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:04 -05:00
Xi Wang
5afb8a3f96 audit: fix signedness bug in audit_log_execve_info()
In the loop, a size_t "len" is used to hold the return value of
audit_log_single_execve_arg(), which returns -1 on error.  In that
case the error handling (len <= 0) will be bypassed since "len" is
unsigned, and the loop continues with (p += len) being wrapped.
Change the type of "len" to signed int to fix the error handling.

	size_t len;
	...
	for (...) {
		len = audit_log_single_execve_arg(...);
		if (len <= 0)
			break;
		p += len;
	}

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:03 -05:00
Peter Moody
10d6836087 audit: comparison on interprocess fields
This allows audit to specify rules in which we compare two fields of a
process.  Such as is the running process uid != to the running process
euid?

Signed-off-by: Peter Moody <pmoody@google.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:03 -05:00
Peter Moody
4a6633ed08 audit: implement all object interfield comparisons
This completes the matrix of interfield comparisons between uid/gid
information for the current task and the uid/gid information for inodes.
aka I can audit based on differences between the euid of the process and
the uid of fs objects.

Signed-off-by: Peter Moody <pmoody@google.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:02 -05:00
Eric Paris
c9fe685f7a audit: allow interfield comparison between gid and ogid
Allow audit rules to compare the gid of the running task to the gid of the
inode in question.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:02 -05:00
Eric Paris
b34b039324 audit: complex interfield comparison helper
Rather than code the same loop over and over implement a helper function which
uses some pointer magic to make it generic enough to be used numerous places
as we implement more audit interfield comparisons

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:02 -05:00
Eric Paris
02d86a568c audit: allow interfield comparison in audit rules
We wish to be able to audit when a uid=500 task accesses a file which is
uid=0.  Or vice versa.  This patch introduces a new audit filter type
AUDIT_FIELD_COMPARE which takes as an 'enum' which indicates which fields
should be compared.  At this point we only define the task->uid vs
inode->uid, but other comparisons can be added.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:01 -05:00
Eric Paris
4043cde8ec audit: do not call audit_getname on error
Just a code cleanup really.  We don't need to make a function call just for
it to return on error.  This also makes the VFS function even easier to follow
and removes a conditional on a hot path.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:01 -05:00
Eric Paris
633b454545 audit: only allow tasks to set their loginuid if it is -1
At the moment we allow tasks to set their loginuid if they have
CAP_AUDIT_CONTROL.  In reality we want tasks to set the loginuid when they
log in and it be impossible to ever reset.  We had to make it mutable even
after it was once set (with the CAP) because on update and admin might have
to restart sshd.  Now sshd would get his loginuid and the next user which
logged in using ssh would not be able to set his loginuid.

Systemd has changed how userspace works and allowed us to make the kernel
work the way it should.  With systemd users (even admins) are not supposed
to restart services directly.  The system will restart the service for
them.  Thus since systemd is going to loginuid==-1, sshd would get -1, and
sshd would be allowed to set a new loginuid without special permissions.

If an admin in this system were to manually start an sshd he is inserting
himself into the system chain of trust and thus, logically, it's his
loginuid that should be used!  Since we have old systems I make this a
Kconfig option.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:00 -05:00
Eric Paris
0a300be6d5 audit: remove task argument to audit_set_loginuid
The function always deals with current.  Don't expose an option
pretending one can use it for something.  You can't.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:17:00 -05:00
Eric Paris
54d3218b31 audit: allow audit matching on inode gid
Much like the ability to filter audit on the uid of an inode collected, we
should be able to filter on the gid of the inode.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:59 -05:00
Eric Paris
efaffd6e44 audit: allow matching on obj_uid
Allow syscall exit filter matching based on the uid of the owner of an
inode used in a syscall.  aka:

auditctl -a always,exit -S open -F obj_uid=0 -F perm=wa

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:59 -05:00
Eric Paris
6422e78de6 audit: remove audit_finish_fork as it can't be called
Audit entry,always rules are not allowed and are automatically changed in
exit,always rules in userspace.  The kernel refuses to load such rules.

Thus a task in the middle of a syscall (and thus in audit_finish_fork())
can only be in one of two states: AUDIT_BUILD_CONTEXT or AUDIT_DISABLED.
Since the current task cannot be in AUDIT_RECORD_CONTEXT we aren't every
going to actually use the code in audit_finish_fork() since it will
return without doing anything.  Thus drop the code.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:59 -05:00
Eric Paris
7ff68e53ec audit: reject entry,always rules
We deprecated entry,always rules a long time ago.  Reject those rules as
invalid.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:58 -05:00
Eric Paris
a4ff8dba7d audit: inline audit_free to simplify the look of generic code
make the conditional a static inline instead of doing it in generic code.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:58 -05:00
Eric Paris
07c4941787 audit: inline checks for not needing to collect aux records
A number of audit hooks make function calls before they determine that
auxilary records do not need to be collected.  Do those checks as static
inlines since the most common case is going to be that records are not
needed and we can skip the function call overhead.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:57 -05:00
Eric Paris
56179a6ec6 audit: drop some potentially inadvisable likely notations
The audit code makes heavy use of likely() and unlikely() macros, but they
don't always make sense.  Drop any that seem questionable and let the
computer do it's thing.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:57 -05:00
Eric Paris
997f5b6444 audit: remove AUDIT_SETUP_CONTEXT as it isn't used
Audit contexts have 3 states.  Disabled, which doesn't collect anything,
build, which collects info but might not emit it, and record, which
collects and emits.  There is a 4th state, setup, which isn't used.  Get
rid of it.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:57 -05:00
Eric Paris
b05d8447e7 audit: inline audit_syscall_entry to reduce burden on archs
Every arch calls:

if (unlikely(current->audit_context))
	audit_syscall_entry()

which requires knowledge about audit (the existance of audit_context) in
the arch code.  Just do it all in static inline in audit.h so that arch's
can remain blissfully ignorant.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:56 -05:00
Eric Paris
d7e7528bcd Audit: push audit success and retcode into arch ptrace.h
The audit system previously expected arches calling to audit_syscall_exit to
supply as arguments if the syscall was a success and what the return code was.
Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things
by converting from negative retcodes to an audit internal magic value stating
success or failure.  This helper was wrong and could indicate that a valid
pointer returned to userspace was a failed syscall.  The fix is to fix the
layering foolishness.  We now pass audit_syscall_exit a struct pt_reg and it
in turns calls back into arch code to collect the return value and to
determine if the syscall was a success or failure.  We also define a generic
is_syscall_success() macro which determines success/failure based on if the
value is < -MAX_ERRNO.  This works for arches like x86 which do not use a
separate mechanism to indicate syscall failure.

We make both the is_syscall_success() and regs_return_value() static inlines
instead of macros.  The reason is because the audit function must take a void*
for the regs.  (uml calls theirs struct uml_pt_regs instead of just struct
pt_regs so audit_syscall_exit can't take a struct pt_regs).  Since the audit
function takes a void* we need to use static inlines to cast it back to the
arch correct structure to dereference it.

The other major change is that on some arches, like ia64, MIPS and ppc, we
change regs_return_value() to give us the negative value on syscall failure.
THE only other user of this macro, kretprobe_example.c, won't notice and it
makes the value signed consistently for the audit functions across all archs.

In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old
audit code as the return value.  But the ptrace_64.h code defined the macro
regs_return_value() as regs[3].  I have no idea which one is correct, but this
patch now uses the regs_return_value() function, so it now uses regs[3].

For powerpc we previously used regs->result but now use the
regs_return_value() function which uses regs->gprs[3].  regs->gprs[3] is
always positive so the regs_return_value(), much like ia64 makes it negative
before calling the audit code when appropriate.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion]
Acked-by: Tony Luck <tony.luck@intel.com> [for ia64]
Acked-by: Richard Weinberger <richard@nod.at> [for uml]
Acked-by: David S. Miller <davem@davemloft.net> [for sparc]
Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
2012-01-17 16:16:56 -05:00
Eric Paris
85e7bac33b seccomp: audit abnormal end to a process due to seccomp
The audit system likes to collect information about processes that end
abnormally (SIGSEGV) as this may me useful intrusion detection information.
This patch adds audit support to collect information when seccomp forces a
task to exit because of misbehavior in a similar way.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:55 -05:00
Eric Paris
16c174bd95 audit: check current inode and containing object when filtering on major and minor
The audit system has the ability to filter on the major and minor number of
the device containing the inode being operated upon.  Lets say that
/dev/sda1 has major,minor 8,1 and that we mount /dev/sda1 on /boot.  Now lets
say we add a watch with a filter on 8,1.  If we proceed to open an inode
inside /boot, such as /vboot/vmlinuz, we will match the major,minor filter.

Lets instead assume that one were to use a tool like debugfs and were to
open /dev/sda1 directly and to modify it's contents.  We might hope that
this would also be logged, but it isn't.  The rules will check the
major,minor of the device containing /dev/sda1.  In other words the rule
would match on the major/minor of the tmpfs mounted at /dev.

I believe these rules should trigger on either device.  The man page is
devoid of useful information about the intended semantics.  It only seems
logical that if you want to know everything that happened on a major,minor
that would include things that happened to the device itself...

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:55 -05:00
Eric Paris
3035c51e8a audit: drop the meaningless and format breaking word 'user'
userspace audit messages look like so:

type=USER msg=audit(1271170549.415:24710): user pid=14722 uid=0 auid=500 ses=1 subj=unconfined_u:unconfined_r:auditctl_t:s0-s0:c0.c1023 msg=''

That third field just says 'user'.  That's useless and doesn't follow the
key=value pair we are trying to enforce.  We already know it came from the
user based on the record type.  Kill that word.  Die.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:54 -05:00
Eric Paris
5195d8e217 audit: dynamically allocate audit_names when not enough space is in the names array
This patch does 2 things.  First it reduces the number of audit_names
allocated in every audit context from 20 to 5.  5 should be enough for all
'normal' syscalls (rename being the worst).  Some syscalls can still touch
more the 5 inodes such as mount.  When rpc filesystem is mounted it will
create inodes and those can exceed 5.  To handle that problem this patch will
dynamically allocate audit_names if it needs more than 5.  This should
decrease the typicall memory usage while still supporting all the possible
kernel operations.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:54 -05:00
Eric Paris
5ef30ee53b audit: make filetype matching consistent with other filters
Every other filter that matches part of the inodes list collected by audit
will match against any of the inodes on that list.  The filetype matching
however had a strange way of doing things.  It allowed userspace to
indicated if it should match on the first of the second name collected by
the kernel.  Name collection ordering seems like a kernel internal and
making userspace rules get that right just seems like a bad idea.  As it
turns out the userspace audit writers had no idea it was doing this and
thus never overloaded the value field.  The kernel always checked the first
name collected which for the tested rules was always correct.

This patch just makes the filetype matching like the major, minor, inode,
and LSM rules in that it will match against any of the names collected.  It
also changes the rule validation to reject the old unused rule types.

Noone knew it was there.  Noone used it.  Why keep around the extra code?

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-17 16:16:54 -05:00
Linus Torvalds
951880e634 Revert "capabitlies: ns_capable can use the cap helpers rather than lsm call"
This reverts commit d2a7009f0b.

J. R. Okajima explains:

 "After this commit, I am afraid access(2) on NFS may not work
  correctly.  The scenario based upon my guess.
   - access(2) overrides the credentials.
   - calls inode_permission() -- ... -- generic_permission() --
      ns_capable().
   - while the old ns_capable() calls security_capable(current_cred()),
     the new ns_capable() calls has_ns_capability(current) --
     security_capable(__task_cred(t)).

  current_cred() returns current->cred which is effective (overridden)
  credentials, but __task_cred(current) returns current->real_cred (the
  NFSD's credential).  And the overridden credentials by access(2) lost."

Requested-by: J. R. Okajima <hooanon05@yahoo.co.jp>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-17 10:19:41 -08:00
Ingo Molnar
b64b223aed Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent 2012-01-17 09:44:17 +01:00
Linus Torvalds
97740400bc Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / Hibernate: Drop the check of swap space size for compressed image
  PM / shmobile: fix A3SP suspend method
  PM / Domains: Skip governor functions for CONFIG_PM_RUNTIME unset
  PM / Domains: Fix build for CONFIG_PM_SLEEP unset
  PM: Make sysrq-o be available for CONFIG_PM unset
2012-01-16 15:02:30 -08:00
Heiko Carstens
4410030646 rcu: Add missing __cpuinit annotation in rcutorture code
"rcu: Add rcutorture CPU-hotplug capability" adds cpu hotplug operations
to the rcutorture code but produces a false positive warning about section
mismatches:

WARNING: vmlinux.o(.text+0x1e420c): Section mismatch in reference from the
	 function rcu_torture_onoff() to the function .cpuinit.text:cpu_up()
	 The function rcu_torture_onoff() references
	 the function __cpuinit cpu_up().
	 This is often because rcu_torture_onoff lacks a __cpuinit
	 annotation or the annotation of cpu_up is wrong.

This commit therefore adds a __cpuinit annotation so the warning goes away.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-01-16 09:44:05 -08:00
Rusty Russell
d8e8ed95cd rcu: Make rcutorture bool parameters really bool (core code)
module_param(bool) used to counter-intuitively take an int.  In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option.  For this version
it'll simply give a warning, but it'll break next kernel version.
This commit makes this change to rcutorture.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-01-16 09:43:56 -08:00
Paul E. McKenney
51aa78271b Merge branch 'rcu/fixes-for-v3.2' into rcu/urgent
Merge reason: Add these commits so that fixes on this branch do not
	conflict with already-mainlined code.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-01-16 09:41:18 -08:00
Steven Rostedt
c10076c430 tracepoints/module: Fix disabling tracepoints with taint CRAP or OOT
Tracepoints are disabled for tainted modules, which is usually because the
module is either proprietary or was forced, and we don't want either of them
using kernel tracepoints.

But, a module can also be tainted by being in the staging directory or
compiled out of tree. Either is fine for use with tracepoints, no need
to punish them.  I found this out when I noticed that my sample trace event
module, when done out of tree, stopped working.

Cc: stable@vger.kernel.org # 3.2
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Dave Jones <davej@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-01-16 11:35:57 -05:00
Kevin Winchester
53999bf34d error: implicit declaration of function 'module_flags_taint'
Recent changes to kernel/module.c caused the following compile
error:

  kernel/module.c: In function ‘show_taint’:
  kernel/module.c:1024:2: error: implicit declaration of function ‘module_flags_taint’ [-Werror=implicit-function-declaration]
  cc1: some warnings being treated as errors

Correct this error by moving the definition of module_flags_taint
outside of the #ifdef CONFIG_MODULE_UNLOAD section.

Signed-off-by: Kevin Winchester <kjwinchester@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-15 16:21:07 -08:00
Linus Torvalds
b3c9dd182e Merge branch 'for-3.3/core' of git://git.kernel.dk/linux-block
* 'for-3.3/core' of git://git.kernel.dk/linux-block: (37 commits)
  Revert "block: recursive merge requests"
  block: Stop using macro stubs for the bio data integrity calls
  blockdev: convert some macros to static inlines
  fs: remove unneeded plug in mpage_readpages()
  block: Add BLKROTATIONAL ioctl
  block: Introduce blk_set_stacking_limits function
  block: remove WARN_ON_ONCE() in exit_io_context()
  block: an exiting task should be allowed to create io_context
  block: ioc_cgroup_changed() needs to be exported
  block: recursive merge requests
  block, cfq: fix empty queue crash caused by request merge
  block, cfq: move icq creation and rq->elv.icq association to block core
  block, cfq: restructure io_cq creation path for io_context interface cleanup
  block, cfq: move io_cq exit/release to blk-ioc.c
  block, cfq: move icq cache management to block core
  block, cfq: move io_cq lookup to blk-ioc.c
  block, cfq: move cfqd->icq_list to request_queue and add request->elv.icq
  block, cfq: reorganize cfq_io_context into generic and cfq specific parts
  block: remove elevator_queue->ops
  block: reorder elevator switch sequence
  ...

Fix up conflicts in:
 - block/blk-cgroup.c
	Switch from can_attach_task to can_attach
 - block/cfq-iosched.c
	conflict with now removed cic index changes (we now use q->id instead)
2012-01-15 12:24:45 -08:00
Linus Torvalds
83c2f912b4 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  perf tools: Fix compile error on x86_64 Ubuntu
  perf report: Fix --stdio output alignment when --showcpuutilization used
  perf annotate: Get rid of field_sep check
  perf annotate: Fix usage string
  perf kmem: Fix a memory leak
  perf kmem: Add missing closedir() calls
  perf top: Add error message for EMFILE
  perf test: Change type of '-v' option to INCR
  perf script: Add missing closedir() calls
  tracing: Fix compile error when static ftrace is enabled
  recordmcount: Fix handling of elf64 big-endian objects.
  perf tools: Add const.h to MANIFEST to make perf-tar-src-pkg work again
  perf tools: Add support for guest/host-only profiling
  perf kvm: Do guest-only counting by default
  perf top: Don't update total_period on process_sample
  perf hists: Stop using 'self' for struct hist_entry
  perf hists: Rename total_session to total_period
  x86: Add counter when debug stack is used with interrupts enabled
  x86: Allow NMIs to hit breakpoints in i386
  x86: Keep current stack in NMI breakpoints
  ...
2012-01-15 11:26:35 -08:00
Linus Torvalds
c49c41a413 Merge branch 'for-linus' of git://selinuxproject.org/~jmorris/linux-security
* 'for-linus' of git://selinuxproject.org/~jmorris/linux-security:
  capabilities: remove __cap_full_set definition
  security: remove the security_netlink_recv hook as it is equivalent to capable()
  ptrace: do not audit capability check when outputing /proc/pid/stat
  capabilities: remove task_ns_* functions
  capabitlies: ns_capable can use the cap helpers rather than lsm call
  capabilities: style only - move capable below ns_capable
  capabilites: introduce new has_ns_capabilities_noaudit
  capabilities: call has_ns_capability from has_capability
  capabilities: remove all _real_ interfaces
  capabilities: introduce security_capable_noaudit
  capabilities: reverse arguments to security_capable
  capabilities: remove the task from capable LSM hook entirely
  selinux: sparse fix: fix several warnings in the security server cod
  selinux: sparse fix: fix warnings in netlink code
  selinux: sparse fix: eliminate warnings for selinuxfs
  selinux: sparse fix: declare selinux_disable() in security.h
  selinux: sparse fix: move selinux_complete_init
  selinux: sparse fix: make selinux_secmark_refcount static
  SELinux: Fix RCU deref check warning in sel_netport_insert()

Manually fix up a semantic mis-merge wrt security_netlink_recv():

 - the interface was removed in commit fd77846152 ("security: remove
   the security_netlink_recv hook as it is equivalent to capable()")

 - a new user of it appeared in commit a38f7907b9 ("crypto: Add
   userspace configuration API")

causing no automatic merge conflict, but Eric Paris pointed out the
issue.
2012-01-14 18:36:33 -08:00
Linus Torvalds
0a80939b3e Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1
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Merge tag 'for-linus' of git://github.com/rustyrussell/linux

Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999  BFCB D920 0E6C D1AD B8F1

* tag 'for-linus' of git://github.com/rustyrussell/linux:
  module_param: check that bool parameters really are bool.
  intelfbdrv.c: bailearly is an int module_param
  paride/pcd: fix bool verbose module parameter.
  module_param: make bool parameters really bool (drivers & misc)
  module_param: make bool parameters really bool (arch)
  module_param: make bool parameters really bool (core code)
  kernel/async: remove redundant declaration.
  printk: fix unnecessary module_param_name.
  lirc_parallel: fix module parameter description.
  module_param: avoid bool abuse, add bint for special cases.
  module_param: check type correctness for module_param_array
  modpost: use linker section to generate table.
  modpost: use a table rather than a giant if/else statement.
  modules: sysfs - export: taint, coresize, initsize
  kernel/params: replace DEBUGP with pr_debug
  module: replace DEBUGP with pr_debug
  module: struct module_ref should contains long fields
  module: Fix performance regression on modules with large symbol tables
  module: Add comments describing how the "strmap" logic works

Fix up conflicts in scripts/mod/file2alias.c due to the new linker-
generated table approach to adding __mod_*_device_table entries.  The
ARM sa11x0 mcp bus needed to be converted to that too.
2012-01-14 12:32:16 -08:00
Barry Song
ee34a37049 PM / Hibernate: Drop the check of swap space size for compressed image
For compressed image, the space required is not known until
we finish compressing and writing all pages.
This patch drops the check, and if swap space is not enough
finally, system can still restore to normal after writing
swap fails for compressed images.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-14 00:41:37 +01:00
Rafael J. Wysocki
dae5cbc244 PM: Make sysrq-o be available for CONFIG_PM unset
After commit 1eb208aea3, "PM: Make
CONFIG_PM depend on (CONFIG_PM_SLEEP || CONFIG_PM_RUNTIME)", the
files under kernel/power are not built unless CONFIG_PM_SLEEP or
CONFIG_PM_RUNTIME is set.  In particular, this causes
kernel/power/poweroff.c to be omitted, even though it should be
compiled, because CONFIG_MAGIC_SYSRQ is set.

Fix the problem by causing kernel/power/Makefile to be processed
for CONFIG_PM unset too.

Reported-and-tested-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-14 00:33:03 +01:00
Oleg Nesterov
163566f60b tracing: send_sigqueue() needs trace_signal_generate() too
Add trace_signal_generate() into send_sigqueue().

send_sigqueue() is very similar to __send_signal(), just it uses
the preallocated info. It should do the same wrt tracing.

Reported-by: Seiji Aguchi <saguchi@redhat.com>
Reviewed-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2012-01-13 18:49:02 +01:00
Oleg Nesterov
6c303d3ab3 tracing: let trace_signal_generate() report more info, kill overflow_fail/lose_info
__send_signal()->trace_signal_generate() doesn't report enough info.
The users want to know was the signal actually delivered or not, and
they also need the shared/private info.

The patch moves trace_signal_generate() at the end of __send_signal()
and adds the 2 additional arguments.

This also allows us to kill trace_signal_overflow_fail/lose_info, we
can simply add the appropriate TRACE_SIGNAL_ "result" codes.

Reported-by: Seiji Aguchi <saguchi@redhat.com>
Reviewed-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2012-01-13 18:48:50 +01:00
Cyrill Gorcunov
028ee4be34 c/r: prctl: add PR_SET_MM codes to set up mm_struct entries
When we restore a task we need to set up text, data and data heap sizes
from userspace to the values a task had at checkpoint time.  This patch
adds auxilary prctl codes for that.

While most of them have a statistical nature (their values are involved
into calculation of /proc/<pid>/statm output) the start_brk and brk values
are used to compute an allowed size of program data segment expansion.
Which means an arbitrary changes of this values might be dangerous
operation.  So to restrict access the following requirements applied to
prctl calls:

 - The process has to have CAP_SYS_ADMIN capability granted.
 - For all opcodes except start_brk/brk members an appropriate
   VMA area must exist and should fit certain VMA flags,
   such as:
   - code segment must be executable but not writable;
   - data segment must not be executable.

start_brk/brk values must not intersect with data segment and must not
exceed RLIMIT_DATA resource limit.

Still the main guard is CAP_SYS_ADMIN capability check.

Note the kernel should be compiled with CONFIG_CHECKPOINT_RESTORE support
otherwise these prctl calls will return -EINVAL.

[akpm@linux-foundation.org: cache current->mm in a local, saving 200 bytes text]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:13 -08:00
Andi Kleen
6e6f0a1f0f panic: don't print redundant backtraces on oops
When an oops causes a panic and panic prints another backtrace it's pretty
common to have the original oops data be scrolled away on a 80x50 screen.

The second backtrace is quite redundant and not needed anyways.

So don't print the panic backtrace when oops_in_progress is true.

[akpm@linux-foundation.org: add comment]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:11 -08:00
Pavel Emelyanov
b8f566b04d sysctl: add the kernel.ns_last_pid control
The sysctl works on the current task's pid namespace, getting and setting
its last_pid field.

Writing is allowed for CAP_SYS_ADMIN-capable tasks thus making it possible
to create a task with desired pid value.  This ability is required badly
for the checkpoint/restore in userspace.

This approach suits all the parties for now.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:11 -08:00
Michael Holzheu
93e13a360b kdump: fix crash_kexec()/smp_send_stop() race in panic()
When two CPUs call panic at the same time there is a possible race
condition that can stop kdump.  The first CPU calls crash_kexec() and the
second CPU calls smp_send_stop() in panic() before crash_kexec() finished
on the first CPU.  So the second CPU stops the first CPU and therefore
kdump fails:

1st CPU:
  panic()->crash_kexec()->mutex_trylock(&kexec_mutex)-> do kdump

2nd CPU:
  panic()->crash_kexec()->kexec_mutex already held by 1st CPU
       ->smp_send_stop()-> stop 1st CPU (stop kdump)

This patch fixes the problem by introducing a spinlock in panic that
allows only one CPU to process crash_kexec() and the subsequent panic
code.

All other CPUs call the weak function panic_smp_self_stop() that stops the
CPU itself.  This function can be overloaded by architecture code.  For
example "tile" can use their lower-power "nap" instruction for that.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:11 -08:00
Michael Holzheu
bec013c40b kdump: crashk_res init check for /sys/kernel/kexec_crash_size
Currently it is possible to set the crash_size via the sysfs
/sys/kernel/kexec_crash_size even if no crash kernel memory has been
defined with the "crashkernel" parameter.  In this case "crashk_res" is
not initialized and crashk_res.start = crashk_res.end = 0.  Unfortunately
resource_size(&crashk_res) returns 1 in this case.  This breaks the s390
implementation of crash_(un)map_reserved_pages().

To fix the problem the correct "old_size" is now calculated in
crash_shrink_memory().  "old_size is set to "0" if crashk_res is not
initialized.  With this change crash_shrink_memory() will do nothing, when
"crashk_res" is not initialized.  It will return "0" for "echo 0 >
/sys/kernel/kexec_crash_size" and -EINVAL for "echo [not zero] >
/sys/kernel/kexec_crash_size".

In addition to that this patch also simplifies the "ret = -EINVAL" vs.
"ret = 0" logic as suggested by Simon Horman.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Dave Young <dyoung@redhat.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:11 -08:00
Michael Holzheu
6480e5a092 kdump: add missing RAM resource in crash_shrink_memory()
When shrinking crashkernel memory using /sys/kernel/kexec_crash_size for
the newly added memory no RAM resource is created at the moment.

Example:

  $ cat /proc/iomem
  00000000-bfffffff : System RAM
    00000000-005b7ac3 : Kernel code
    005b7ac4-009743bf : Kernel data
    009bb000-00a85c33 : Kernel bss
  c0000000-cfffffff : Crash kernel
  d0000000-ffffffff : System RAM

  $ echo 0 > /sys/kernel/kexec_crash_size
  $ cat /proc/iomem
  00000000-bfffffff : System RAM
    00000000-005b7ac3 : Kernel code
    005b7ac4-009743bf : Kernel data
    009bb000-00a85c33 : Kernel bss
                                   <<-- here is System RAM missing
  d0000000-ffffffff : System RAM

One result of this bug is that the memory chunk can never be set offline
using memory hotplug.  With this patch I insert a new "System RAM"
resource for the released memory.  Then the upper example looks like the
following:

  $ echo 0 > /sys/kernel/kexec_crash_size
  $ cat /proc/iomem
  00000000-bfffffff : System RAM
    00000000-005b7ac3 : Kernel code
    005b7ac4-009743bf : Kernel data
    009bb000-00a85c33 : Kernel bss
  c0000000-cfffffff : System RAM   <<-- new rescoure
  d0000000-ffffffff : System RAM

And now I can set chunk c0000000-cfffffff offline.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:11 -08:00
WANG Cong
a3dd332305 kexec: remove KMSG_DUMP_KEXEC
KMSG_DUMP_KEXEC is useless because we already save kernel messages inside
/proc/vmcore, and it is unsafe to allow modules to do other stuffs in a
crash dump scenario.

[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Reported-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:11 -08:00
Joe Perches
9402c95f34 treewide: remove useless NORET_TYPE macro and uses
It's a very old and now unused prototype marking so just delete it.

Neaten panic pointer argument style to keep checkpatch quiet.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:03 -08:00
Stephen Boyd
efeb156e72 kprobes: silence DEBUG_STRICT_USER_COPY_CHECKS=y warning
Enabling DEBUG_STRICT_USER_COPY_CHECKS causes the following warning:

  In file included from arch/x86/include/asm/uaccess.h:573,
                   from kernel/kprobes.c:55:
  In function 'copy_from_user',
      inlined from 'write_enabled_file_bool' at
      kernel/kprobes.c:2191:
  arch/x86/include/asm/uaccess_64.h:65:
  warning: call to 'copy_from_user_overflow' declared with attribute warning: copy_from_user() buffer size is not provably correct

presumably due to buf_size being signed causing GCC to fail to see that
buf_size can't become negative.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:02 -08:00
Rusty Russell
2329abfa34 module_param: make bool parameters really bool (core code)
module_param(bool) used to counter-intuitively take an int.  In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option.  For this version
it'll simply give a warning, but it'll break next kernel version.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:18 +10:30
Rusty Russell
6d6a55ec08 kernel/async: remove redundant declaration.
It's in linux/init.h, and I'm about to change it to a bool.

Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:18 +10:30
Rusty Russell
29d4d6df10 printk: fix unnecessary module_param_name.
You don't need module_param_name if the name is the same!

Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:17 +10:30
Rusty Russell
69116f279a module_param: avoid bool abuse, add bint for special cases.
For historical reasons, we allow module_param(bool) to take an int (or
an unsigned int).  That's going away.

A few drivers really want an int: they set it to -1 and a parameter
will set it to 0 or 1.  This sucks: reading them from sysfs will give
'Y' for both -1 and 1, but if we change it to an int, then the users
might be broken (if they did "param" instead of "param=1").

Use a new 'bint' parser for them.

(ntfs has a different problem: it needs an int for debug_msgs because
it's also exposed via sysctl.)

Cc: Steve Glendinning <steve.glendinning@smsc.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Cc: Christoph Raisch <raisch@de.ibm.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: linux390@de.ibm.com
Cc: Anton Altaparmakov <anton@tuxera.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: lm-sensors@lm-sensors.org
Cc: linux-rdma@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: alsa-devel@alsa-project.org
Acked-by: Takashi Iwai <tiwai@suse.de> (For the sound part)
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> (For the hwmon driver)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:17 +10:30
Kay Sievers
cca3e70730 modules: sysfs - export: taint, coresize, initsize
Recent tools do not want to use /proc to retrieve module information. A few
values are currently missing from sysfs to replace the information available
in /proc/modules.

This adds /sys/module/*/{coresize,initsize,taint} attributes.

TAINT_PROPRIETARY_MODULE (P) and TAINT_OOT_MODULE (O) flags are both always
shown now, and do no longer exclude each other, also in /proc/modules.

Replace the open-coded sysfs attribute initializers with the __ATTR() macro.

Add the new attributes to Documentation/ABI.

Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:15 +10:30
Jim Cromie
8487bfd954 kernel/params: replace DEBUGP with pr_debug
Use more flexible pr_debug.  This allows:

  echo "module params +p" > /dbg/dynamic_debug/control

to turn on debug messages when needed.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:15 +10:30
Jim Cromie
5e12416927 module: replace DEBUGP with pr_debug
Use more flexible pr_debug.  This allows:

  echo "module module +p" > /dbg/dynamic_debug/control

to turn on debug messages when needed.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:15 +10:30
Eric Dumazet
bd77c04772 module: struct module_ref should contains long fields
module_ref contains two "unsigned int" fields.

Thats now too small, since some machines can open more than 2^32 files.

Check commit 518de9b39e (fs: allow for more than 2^31 files) for
reference.

We can add an aligned(2 * sizeof(unsigned long)) attribute to force
alloc_percpu() allocating module_ref areas in single cache lines.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Tejun Heo <tj@kernel.org>
CC: Robin Holt <holt@sgi.com>
CC: David Miller <davem@davemloft.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:14 +10:30
Kevin Cernekee
48fd11880b module: Fix performance regression on modules with large symbol tables
Looking at /proc/kallsyms, one starts to ponder whether all of the extra
strtab-related complexity in module.c is worth the memory savings.

Instead of making the add_kallsyms() loop even more complex, I tried the
other route of deleting the strmap logic and naively copying each string
into core_strtab with no consideration for consolidating duplicates.

Performance on an "already exists" insmod of nvidia.ko (runs
add_kallsyms() but does not actually initialize the module):

	Original scheme: 1.230s
	With naive copying: 0.058s

Extra space used: 35k (of a 408k module).

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <73defb5e4bca04a6431392cc341112b1@localhost>
2012-01-13 09:32:14 +10:30
Kevin Cernekee
70b1e9161e module: Add comments describing how the "strmap" logic works
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:13 +10:30
Linus Torvalds
b8bf17d311 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix lockup by limiting load-balance retries on lock-break
  sched: Fix CONFIG_CGROUP_SCHED dependency
  sched: Remove empty #ifdefs
2012-01-11 22:52:48 -08:00
Linus Torvalds
541048a1d3 Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, reboot: Fix typo in nmi reboot path
  x86, NMI: Add to_cpumask() to silence compile warning
  x86, NMI: NMI selftest depends on the local apic
  x86: Add stack top margin for stack overflow checking
  x86, NMI: NMI-selftest should handle the UP case properly
  x86: Fix the 32-bit stackoverflow-debug build
  x86, NMI: Add knob to disable using NMI IPIs to stop cpus
  x86, NMI: Add NMI IPI selftest
  x86, reboot: Use NMI instead of REBOOT_VECTOR to stop cpus
  x86: Clean up the range of stack overflow checking
  x86: Panic on detection of stack overflow
  x86: Check stack overflow in detail
2012-01-11 19:13:04 -08:00
Peter Zijlstra
bced76aeac sched: Fix lockup by limiting load-balance retries on lock-break
Eric and David reported dead machines and traced it to commit
a195f004 ("sched: Fix load-balance lock-breaking"), it turns out
there's still a scenario where we can end up re-trying forever.

Since there is no strict forward progress guarantee in the
load-balance iteration we can get stuck re-retrying the same
task-set over and over.

Creating a forward progress guarantee with the existing
structure is somewhat non-trivial, for now simply terminate the
retry loop after a few tries.

Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: David Ahern <dsahern@gmail.com>
[ logic cleanup as suggested by Eric ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1326297936.2442.157.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-11 17:15:12 +01:00
Linus Torvalds
001a541ea9 Merge branch 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux
* 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: move MIN_WRITEBACK_PAGES to fs-writeback.c
  writeback: balanced_rate cannot exceed write bandwidth
  writeback: do strict bdi dirty_exceeded
  writeback: avoid tiny dirty poll intervals
  writeback: max, min and target dirty pause time
  writeback: dirty ratelimit - think time compensation
  btrfs: fix dirtied pages accounting on sub-page writes
  writeback: fix dirtied pages accounting on redirty
  writeback: fix dirtied pages accounting on sub-page writes
  writeback: charge leaked page dirties to active tasks
  writeback: Include all dirty inodes in background writeback
2012-01-10 16:59:59 -08:00
Linus Torvalds
40ba587923 Merge branch 'akpm' (aka "Andrew's patch-bomb")
Andrew elucidates:
 - First installmeant of MM.  We have a HUGE number of MM patches this
   time.  It's crazy.
 - MAINTAINERS updates
 - backlight updates
 - leds
 - checkpatch updates
 - misc ELF stuff
 - rtc updates
 - reiserfs
 - procfs
 - some misc other bits

* akpm: (124 commits)
  user namespace: make signal.c respect user namespaces
  workqueue: make alloc_workqueue() take printf fmt and args for name
  procfs: add hidepid= and gid= mount options
  procfs: parse mount options
  procfs: introduce the /proc/<pid>/map_files/ directory
  procfs: make proc_get_link to use dentry instead of inode
  signal: add block_sigmask() for adding sigmask to current->blocked
  sparc: make SA_NOMASK a synonym of SA_NODEFER
  reiserfs: don't lock root inode searching
  reiserfs: don't lock journal_init()
  reiserfs: delay reiserfs lock until journal initialization
  reiserfs: delete comments referring to the BKL
  drivers/rtc/interface.c: fix alarm rollover when day or month is out-of-range
  drivers/rtc/rtc-twl.c: add DT support for RTC inside twl4030/twl6030
  drivers/rtc/: remove redundant spi driver bus initialization
  drivers/rtc/rtc-jz4740.c: make jz4740_rtc_driver static
  drivers/rtc/rtc-mc13xxx.c: make mc13xxx_rtc_idtable static
  rtc: convert drivers/rtc/* to use module_platform_driver()
  drivers/rtc/rtc-wm831x.c: convert to devm_kzalloc()
  drivers/rtc/rtc-wm831x.c: remove unused period IRQ handler
  ...
2012-01-10 16:42:48 -08:00
Serge E. Hallyn
6b550f9495 user namespace: make signal.c respect user namespaces
ipc/mqueue.c: for __SI_MESQ, convert the uid being sent to recipient's
user namespace. (new, thanks Oleg)

__send_signal: convert current's uid to the recipient's user namespace
for any siginfo which is not SI_FROMKERNEL (patch from Oleg, thanks
again :)

do_notify_parent and do_notify_parent_cldstop: map task's uid to parent's
user namespace

ptrace_signal maps parent's uid into current's user namespace before
including in signal to current.  IIUC Oleg has argued that this shouldn't
matter as the debugger will play with it, but it seems like not converting
the value currently being set is misleading.

Changelog:
Sep 20: Inspired by Oleg's suggestion, define map_cred_ns() helper to
	simplify callers and help make clear what we are translating
        (which uid into which namespace).  Passing the target task would
	make callers even easier to read, but we pass in user_ns because
	current_user_ns() != task_cred_xxx(current, user_ns).
Sep 20: As recommended by Oleg, also put task_pid_vnr() under rcu_read_lock
	in ptrace_signal().
Sep 23: In send_signal(), detect when (user) signal is coming from an
	ancestor or unrelated user namespace.  Pass that on to __send_signal,
	which sets si_uid to 0 or overflowuid if needed.
Oct 12: Base on Oleg's fixup_uid() patch.  On top of that, handle all
	SI_FROMKERNEL cases at callers, because we can't assume sender is
	current in those cases.
Nov 10: (mhelsley) rename fixup_uid to more meaningful usern_fixup_signal_uid
Nov 10: (akpm) make the !CONFIG_USER_NS case clearer

Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
From: Serge Hallyn <serge.hallyn@canonical.com>
Subject: __send_signal: pass q->info, not info, to userns_fixup_signal_uid (v2)

Eric Biederman pointed out that passing info is a bug and could lead to a
NULL pointer deref to boot.

A collection of signal, securebits, filecaps, cap_bounds, and a few other
ltp tests passed with this kernel.

Changelog:
    Nov 18: previous patch missed a leading '&'

Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
From: Dan Carpenter <dan.carpenter@oracle.com>
Subject: ipc/mqueue: lock() => unlock() typo

There was a double lock typo introduced in b085f4bd6b21 "user namespace:
make signal.c respect user namespaces"

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:54 -08:00
Tejun Heo
b196be89cd workqueue: make alloc_workqueue() take printf fmt and args for name
alloc_workqueue() currently expects the passed in @name pointer to remain
accessible.  This is inconvenient and a bit silly given that the whole wq
is being dynamically allocated.  This patch updates alloc_workqueue() and
friends to take printf format string instead of opaque string and matching
varargs at the end.  The name is allocated together with the wq and
formatted.

alloc_ordered_workqueue() is converted to a macro to unify varargs
handling with alloc_workqueue(), and, while at it, add comment to
alloc_workqueue().

None of the current in-kernel users pass in string with '%' as constant
name and this change shouldn't cause any problem.

[akpm@linux-foundation.org: use __printf]
Signed-off-by: Tejun Heo <tj@kernel.org>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:54 -08:00
Matt Fleming
5e6292c0f2 signal: add block_sigmask() for adding sigmask to current->blocked
Abstract the code sequence for adding a signal handler's sa_mask to
current->blocked because the sequence is identical for all architectures.
Furthermore, in the past some architectures actually got this code wrong,
so introduce a wrapper that all architectures can use.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:54 -08:00
KAMEZAWA Hiroyuki
43d2b11324 tracepoint: add tracepoints for debugging oom_score_adj
oom_score_adj is used for guarding processes from OOM-Killer.  One of
problem is that it's inherited at fork().  When a daemon set oom_score_adj
and make children, it's hard to know where the value is set.

This patch adds some tracepoints useful for debugging. This patch adds
3 trace points.
  - creating new task
  - renaming a task (exec)
  - set oom_score_adj

To debug, users need to enable some trace pointer. Maybe filtering is useful as

# EVENT=/sys/kernel/debug/tracing/events/task/
# echo "oom_score_adj != 0" > $EVENT/task_newtask/filter
# echo "oom_score_adj != 0" > $EVENT/task_rename/filter
# echo 1 > $EVENT/enable
# EVENT=/sys/kernel/debug/tracing/events/oom/
# echo 1 > $EVENT/enable

output will be like this.
# grep oom /sys/kernel/debug/tracing/trace
bash-7699  [007] d..3  5140.744510: oom_score_adj_update: pid=7699 comm=bash oom_score_adj=-1000
bash-7699  [007] ...1  5151.818022: task_newtask: pid=7729 comm=bash clone_flags=1200011 oom_score_adj=-1000
ls-7729  [003] ...2  5151.818504: task_rename: pid=7729 oldcomm=bash newcomm=ls oom_score_adj=-1000
bash-7699  [002] ...1  5175.701468: task_newtask: pid=7730 comm=bash clone_flags=1200011 oom_score_adj=-1000
grep-7730  [007] ...2  5175.701993: task_rename: pid=7730 oldcomm=bash newcomm=grep oom_score_adj=-1000

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:44 -08:00
Stanislaw Gruszka
c6968e73b9 PM/Hibernate: do not count debug pages as savable
When debugging with CONFIG_DEBUG_PAGEALLOC and debug_guardpage_minorder >
0, we have lot of free pages that are not marked so.  Snapshot code
account them as savable, what cause hibernate memory preallocation
failure.

It is pretty hard to make hibernate allocation succeed with
debug_guardpage_minorder=1.  This change at least make it possible when
system has relatively big amount of RAM.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:42 -08:00
Linus Torvalds
3dcf6c1b6b Merge branch 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (74 commits)
  KVM: PPC: Whitespace fix for kvm.h
  KVM: Fix whitespace in kvm_para.h
  KVM: PPC: annotate kvm_rma_init as __init
  KVM: x86 emulator: implement RDPMC (0F 33)
  KVM: x86 emulator: fix RDPMC privilege check
  KVM: Expose the architectural performance monitoring CPUID leaf
  KVM: VMX: Intercept RDPMC
  KVM: SVM: Intercept RDPMC
  KVM: Add generic RDPMC support
  KVM: Expose a version 2 architectural PMU to a guests
  KVM: Expose kvm_lapic_local_deliver()
  KVM: x86 emulator: Use opcode::execute for Group 9 instruction
  KVM: x86 emulator: Use opcode::execute for Group 4/5 instructions
  KVM: x86 emulator: Use opcode::execute for Group 1A instruction
  KVM: ensure that debugfs entries have been created
  KVM: drop bsp_vcpu pointer from kvm struct
  KVM: x86: Consolidate PIT legacy test
  KVM: x86: Do not rely on implicit inclusions
  KVM: Make KVM_INTEL depend on CPU_SUP_INTEL
  KVM: Use memdup_user instead of kmalloc/copy_from_user
  ...
2012-01-10 09:57:11 -08:00
Hiroshi Shimamoto
9b9fb610f6 sched: Remove empty #ifdefs
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4F0B8525.8070901@ct.jp.nec.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-10 09:57:41 +01:00
Linus Torvalds
db0c2bf69a Merge branch 'for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
* 'for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits)
  cgroup: fix to allow mounting a hierarchy by name
  cgroup: move assignement out of condition in cgroup_attach_proc()
  cgroup: Remove task_lock() from cgroup_post_fork()
  cgroup: add sparse annotation to cgroup_iter_start() and cgroup_iter_end()
  cgroup: mark cgroup_rmdir_waitq and cgroup_attach_proc() as static
  cgroup: only need to check oldcgrp==newgrp once
  cgroup: remove redundant get/put of task struct
  cgroup: remove redundant get/put of old css_set from migrate
  cgroup: Remove unnecessary task_lock before fetching css_set on migration
  cgroup: Drop task_lock(parent) on cgroup_fork()
  cgroups: remove redundant get/put of css_set from css_set_check_fetched()
  resource cgroups: remove bogus cast
  cgroup: kill subsys->can_attach_task(), pre_attach() and attach_task()
  cgroup, cpuset: don't use ss->pre_attach()
  cgroup: don't use subsys->can_attach_task() or ->attach_task()
  cgroup: introduce cgroup_taskset and use it in subsys->can_attach(), cancel_attach() and attach()
  cgroup: improve old cgroup handling in cgroup_attach_proc()
  cgroup: always lock threadgroup during migration
  threadgroup: extend threadgroup_lock() to cover exit and exec
  threadgroup: rename signal->threadgroup_fork_lock to ->group_rwsem
  ...

Fix up conflict in kernel/cgroup.c due to commit e0197aae59: "cgroups:
fix a css_set not found bug in cgroup_attach_proc" that already
mentioned that the bug is fixed (differently) in Tejun's cgroup
patchset. This one, in other words.
2012-01-09 12:59:24 -08:00
Jesper Juhl
a0e86bd425 audit: always follow va_copy() with va_end()
A call to va_copy() should always be followed by a call to va_end() in
the same function.  In kernel/autit.c::audit_log_vformat() this is not
always done.  This patch makes sure va_end() is always called.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-08 14:15:21 -08:00
Linus Torvalds
98793265b4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (53 commits)
  Kconfig: acpi: Fix typo in comment.
  misc latin1 to utf8 conversions
  devres: Fix a typo in devm_kfree comment
  btrfs: free-space-cache.c: remove extra semicolon.
  fat: Spelling s/obsolate/obsolete/g
  SCSI, pmcraid: Fix spelling error in a pmcraid_err() call
  tools/power turbostat: update fields in manpage
  mac80211: drop spelling fix
  types.h: fix comment spelling for 'architectures'
  typo fixes: aera -> area, exntension -> extension
  devices.txt: Fix typo of 'VMware'.
  sis900: Fix enum typo 'sis900_rx_bufer_status'
  decompress_bunzip2: remove invalid vi modeline
  treewide: Fix comment and string typo 'bufer'
  hyper-v: Update MAINTAINERS
  treewide: Fix typos in various parts of the kernel, and fix some comments.
  clockevents: drop unknown Kconfig symbol GENERIC_CLOCKEVENTS_MIGR
  gpio: Kconfig: drop unknown symbol 'CS5535_GPIO'
  leds: Kconfig: Fix typo 'D2NET_V2'
  sound: Kconfig: drop unknown symbol ARCH_CLPS7500
  ...

Fix up trivial conflicts in arch/powerpc/platforms/40x/Kconfig (some new
kconfig additions, close to removed commented-out old ones)
2012-01-08 13:21:22 -08:00
Linus Torvalds
eb59c505f8 Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits)
  PM / Hibernate: Implement compat_ioctl for /dev/snapshot
  PM / Freezer: fix return value of freezable_schedule_timeout_killable()
  PM / shmobile: Allow the A4R domain to be turned off at run time
  PM / input / touchscreen: Make st1232 use device PM QoS constraints
  PM / QoS: Introduce dev_pm_qos_add_ancestor_request()
  PM / shmobile: Remove the stay_on flag from SH7372's PM domains
  PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume
  PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode
  PM: Drop generic_subsys_pm_ops
  PM / Sleep: Remove forward-only callbacks from AMBA bus type
  PM / Sleep: Remove forward-only callbacks from platform bus type
  PM: Run the driver callback directly if the subsystem one is not there
  PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
  PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412.
  PM / Sleep: Merge internal functions in generic_ops.c
  PM / Sleep: Simplify generic system suspend callbacks
  PM / Hibernate: Remove deprecated hibernation snapshot ioctls
  PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
  ARM: S3C64XX: Implement basic power domain support
  PM / shmobile: Use common always on power domain governor
  ...

Fix up trivial conflict in fs/xfs/xfs_buf.c due to removal of unused
XBT_FORCE_SLEEP bit
2012-01-08 13:10:57 -08:00
Linus Torvalds
972b2c7199 Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (165 commits)
  reiserfs: Properly display mount options in /proc/mounts
  vfs: prevent remount read-only if pending removes
  vfs: count unlinked inodes
  vfs: protect remounting superblock read-only
  vfs: keep list of mounts for each superblock
  vfs: switch ->show_options() to struct dentry *
  vfs: switch ->show_path() to struct dentry *
  vfs: switch ->show_devname() to struct dentry *
  vfs: switch ->show_stats to struct dentry *
  switch security_path_chmod() to struct path *
  vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb
  vfs: trim includes a bit
  switch mnt_namespace ->root to struct mount
  vfs: take /proc/*/mounts and friends to fs/proc_namespace.c
  vfs: opencode mntget() mnt_set_mountpoint()
  vfs: spread struct mount - remaining argument of next_mnt()
  vfs: move fsnotify junk to struct mount
  vfs: move mnt_devname
  vfs: move mnt_list to struct mount
  vfs: switch pnode.h macros to struct mount *
  ...
2012-01-08 12:19:57 -08:00
Ingo Molnar
636f0c70f2 Merge branch 'tip/perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core 2012-01-08 12:31:24 +01:00
Ingo Molnar
675eef66e3 Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core 2012-01-08 09:51:24 +01:00
Linus Torvalds
02550d61f4 devicetree/next changes queued for v3.3 merge window
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Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux-2.6

devicetree/next changes queued for v3.3 merge window

* tag 'devicetree-for-linus-20120104' of git://git.secretlab.ca/git/linux-2.6:
  ARM: prom.h: Fix build error by removing unneeded header file
  irq: check domain hwirq range for DT translate
  dt: add empty of_get_node/of_put_node functions
  of/pdt: fix section mismatch warning
  i2c-designware: add OF binding support
  dt/i2c: Enumerate some of the known trivial i2c devices
  dt: reform for_each_property to for_each_property_of_node
  ARM/of: allow *machine_desc.dt_compat to be const
  of/base: Take NULL string into account for property with multiple strings
  OF/device-tree: Add some entries to vendor-prefixes.txt

Fix up trivial add-add conflicts in include/linux/of.h
2012-01-07 12:18:52 -08:00
Linus Torvalds
7affca3537 Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits)
  arm: fix up some samsung merge sysdev conversion problems
  firmware: Fix an oops on reading fw_priv->fw in sysfs loading file
  Drivers:hv: Fix a bug in vmbus_driver_unregister()
  driver core: remove __must_check from device_create_file
  debugfs: add missing #ifdef HAS_IOMEM
  arm: time.h: remove device.h #include
  driver-core: remove sysdev.h usage.
  clockevents: remove sysdev.h
  arm: convert sysdev_class to a regular subsystem
  arm: leds: convert sysdev_class to a regular subsystem
  kobject: remove kset_find_obj_hinted()
  m86k: gpio - convert sysdev_class to a regular subsystem
  mips: txx9_sram - convert sysdev_class to a regular subsystem
  mips: 7segled - convert sysdev_class to a regular subsystem
  sh: dma - convert sysdev_class to a regular subsystem
  sh: intc - convert sysdev_class to a regular subsystem
  power: suspend - convert sysdev_class to a regular subsystem
  power: qe_ic - convert sysdev_class to a regular subsystem
  power: cmm - convert sysdev_class to a regular subsystem
  s390: time - convert sysdev_class to a regular subsystem
  ...

Fix up conflicts with 'struct sysdev' removal from various platform
drivers that got changed:
 - arch/arm/mach-exynos/cpu.c
 - arch/arm/mach-exynos/irq-eint.c
 - arch/arm/mach-s3c64xx/common.c
 - arch/arm/mach-s3c64xx/cpu.c
 - arch/arm/mach-s5p64x0/cpu.c
 - arch/arm/mach-s5pv210/common.c
 - arch/arm/plat-samsung/include/plat/cpu.h
 - arch/powerpc/kernel/sysfs.c
and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h
2012-01-07 12:03:30 -08:00
Al Viro
34c80b1d93 vfs: switch ->show_options() to struct dentry *
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-06 23:19:54 -05:00
Al Viro
d8c9584ea2 vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-06 23:16:53 -05:00
Al Viro
ece2ccb668 Merge branches 'vfsmount-guts', 'umode_t' and 'partitions' into Z 2012-01-06 23:15:54 -05:00
Linus Torvalds
770e1b035d Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm
* 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (207 commits)
  ARM: 7267/1: Remove BUILD_BUG_ON from asm/bug.h
  ARM: 7269/1: mach-sa1100: fix sched_clock breakage
  ARM: 7198/1: arm/imx6: add restart support for imx6q
  ARM: restart: remove the now empty arch_reset()
  ARM: restart: remove comments about adding code to arch_reset()
  ARM: restart: lpc32xx & u300: remove unnecessary printk
  ARM: restart: plat-samsung: remove plat/reset.h and s5p_reset_hook
  ARM: restart: w90x900: use new restart hook
  ARM: restart: Versatile Express: use new restart hook
  ARM: restart: versatile: use new restart hook
  ARM: restart: u300: use new restart hook
  ARM: restart: tegra: use new restart hook
  ARM: restart: spear: use new restart hook
  ARM: restart: shark: use new restart hook
  ARM: restart: sa1100: use new restart hook
  ARM: 7252/1: restart: S5PV210: use new restart hook
  ARM: 7251/1: restart: S5PC100: use new restart hook
  ARM: 7250/1: restart: S5P64X0: use new restart hook
  ARM: 7266/1: restart: S3C64XX: use new restart hook
  ARM: 7265/1: restart: S3C24XX: use new restart hook
  ...

Fix up trivial conflict in arch/arm/mm/init.c due to removal of
memblock_init() clashing with the movement of the sorting of the meminfo
array.
2012-01-06 18:15:25 -08:00
Linus Torvalds
376613e81d Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, tsc: Skip TSC synchronization checks for tsc=reliable
  clocksource: Convert tcb_clksrc to use clocksource_register_hz/khz
  clocksource: cris: Convert to clocksource_register_khz
  clocksource: xtensa: Convert to clocksource_register_hz/khz
  clocksource: um: Convert to clocksource_register_hz/khz
  clocksource: parisc: Convert to clocksource_register_hz/khz
  clocksource: m86k: Convert to clocksource_register_hz/khz
  time: x86: Replace LATCH with PIT_LATCH in i8253 clocksource driver
  time: x86: Remove CLOCK_TICK_RATE from acpi_pm clocksource driver
  time: x86: Remove CLOCK_TICK_RATE from mach_timer.h
  time: x86: Remove CLOCK_TICK_RATE from tsc code
  time: Fix spelling mistakes in new comments
  time: fix bogus comment in timekeeping_get_ns_raw
2012-01-06 13:57:44 -08:00
Greg Kroah-Hartman
ff4b8a57f0 Merge branch 'driver-core-next' into Linux 3.2
This resolves the conflict in the arch/arm/mach-s3c64xx/s3c6400.c file,
and it fixes the build error in the arch/x86/kernel/microcode_core.c
file, that the merge did not catch.

The microcode_core.c patch was provided by Stephen Rothwell
<sfr@canb.auug.org.au> who was invaluable in the merge issues involved
with the large sysdev removal process in the driver-core tree.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-06 11:42:52 -08:00
Linus Torvalds
0db49b72bc Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
  sched/tracing: Add a new tracepoint for sleeptime
  sched: Disable scheduler warnings during oopses
  sched: Fix cgroup movement of waking process
  sched: Fix cgroup movement of newly created process
  sched: Fix cgroup movement of forking process
  sched: Remove cfs bandwidth period check in tg_set_cfs_period()
  sched: Fix load-balance lock-breaking
  sched: Replace all_pinned with a generic flags field
  sched: Only queue remote wakeups when crossing cache boundaries
  sched: Add missing rcu_dereference() around ->real_parent usage
  [S390] fix cputime overflow in uptime_proc_show
  [S390] cputime: add sparse checking and cleanup
  sched: Mark parent and real_parent as __rcu
  sched, nohz: Fix missing RCU read lock
  sched, nohz: Set the NOHZ_BALANCE_KICK flag for idle load balancer
  sched, nohz: Fix the idle cpu check in nohz_idle_balance
  sched: Use jump_labels for sched_feat
  sched/accounting: Fix parameter passing in task_group_account_field
  sched/accounting: Fix user/system tick double accounting
  sched/accounting: Re-use scheduler statistics for the root cgroup
  ...

Fix up conflicts in
 - arch/ia64/include/asm/cputime.h, include/asm-generic/cputime.h
	usecs_to_cputime64() vs the sparse cleanups
 - kernel/sched/fair.c, kernel/time/tick-sched.c
	scheduler changes in multiple branches
2012-01-06 08:44:54 -08:00
Linus Torvalds
35b740e466 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (106 commits)
  perf kvm: Fix copy & paste error in description
  perf script: Kill script_spec__delete
  perf top: Fix a memory leak
  perf stat: Introduce get_ratio_color() helper
  perf session: Remove impossible condition check
  perf tools: Fix feature-bits rework fallout, remove unused variable
  perf script: Add generic perl handler to process events
  perf tools: Use for_each_set_bit() to iterate over feature flags
  perf tools: Unify handling of features when writing feature section
  perf report: Accept fifos as input file
  perf tools: Moving code in some files
  perf tools: Fix out-of-bound access to struct perf_session
  perf tools: Continue processing header on unknown features
  perf tools: Improve macros for struct feature_ops
  perf: builtin-record: Document and check that mmap_pages must be a power of two.
  perf: builtin-record: Provide advice if mmap'ing fails with EPERM.
  perf tools: Fix truncated annotation
  perf script: look up thread using tid instead of pid
  perf tools: Look up thread names for system wide profiling
  perf tools: Fix comm for processes with named threads
  ...
2012-01-06 08:02:58 -08:00
Linus Torvalds
423d091dfe Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  cpu: Export cpu_up()
  rcu: Apply ACCESS_ONCE() to rcu_boost() return value
  Revert "rcu: Permit rt_mutex_unlock() with irqs disabled"
  docs: Additional LWN links to RCU API
  rcu: Augment rcu_batch_end tracing for idle and callback state
  rcu: Add rcutorture tests for srcu_read_lock_raw()
  rcu: Make rcutorture test for hotpluggability before offlining CPUs
  driver-core/cpu: Expose hotpluggability to the rest of the kernel
  rcu: Remove redundant rcu_cpu_stall_suppress declaration
  rcu: Adaptive dyntick-idle preparation
  rcu: Keep invoking callbacks if CPU otherwise idle
  rcu: Irq nesting is always 0 on rcu_enter_idle_common
  rcu: Don't check irq nesting from rcu idle entry/exit
  rcu: Permit dyntick-idle with callbacks pending
  rcu: Document same-context read-side constraints
  rcu: Identify dyntick-idle CPUs on first force_quiescent_state() pass
  rcu: Remove dynticks false positives and RCU failures
  rcu: Reduce latency of rcu_prepare_for_idle()
  rcu: Eliminate RCU_FAST_NO_HZ grace-period hang
  rcu: Avoid needlessly IPIing CPUs at GP end
  ...
2012-01-06 08:02:40 -08:00
Linus Torvalds
1483b38235 Merge branch 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  printk, lockdep: Switch to tracked irq ops
  printk, lockdep: Remove superfluous preempt_disable()
  printk, lockdep: Disable lock debugging on zap_locks()
2012-01-06 08:01:59 -08:00
Linus Torvalds
4a2164a7db Merge branch 'core-memblock-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-memblock-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  memblock: Reimplement memblock allocation using reverse free area iterator
  memblock: Kill early_node_map[]
  score: Use HAVE_MEMBLOCK_NODE_MAP
  s390: Use HAVE_MEMBLOCK_NODE_MAP
  mips: Use HAVE_MEMBLOCK_NODE_MAP
  ia64: Use HAVE_MEMBLOCK_NODE_MAP
  SuperH: Use HAVE_MEMBLOCK_NODE_MAP
  sparc: Use HAVE_MEMBLOCK_NODE_MAP
  powerpc: Use HAVE_MEMBLOCK_NODE_MAP
  memblock: Implement memblock_add_node()
  memblock: s/memblock_analyze()/memblock_allow_resize()/ and update users
  memblock: Track total size of regions automatically
  powerpc: Cleanup memblock usage
  memblock: Reimplement memblock_enforce_memory_limit() using __memblock_remove()
  memblock: Make memblock functions handle overflowing range @size
  memblock: Reimplement __memblock_remove() using memblock_isolate_range()
  memblock: Separate out memblock_isolate_range() from memblock_set_node()
  memblock: Kill memblock_init()
  memblock: Kill sentinel entries at the end of static region arrays
  memblock: Add __memblock_dump_all()
  ...
2012-01-06 07:54:53 -08:00
Linus Torvalds
15f043a65f Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep/waitqueues: Add better annotation
  lockdep, bug: Exclude TAINT_OOT_MODULE from disabling lock debugging
  lockdep: Print lock name in lockdep_init_error()
  init/main.c: Execute lockdep_init() as early as possible
  lockdep, kmemcheck: Annotate ->lock in lockdep_init_map()
  lockdep, rtmutex, bug: Show taint flags on error
  lockdep, bug: Exclude TAINT_FIRMWARE_WORKAROUND from disabling lockdep
  lockdep: Always try to set ->class_cache in register_lock_class() lockdep_init_map()
2012-01-06 07:53:52 -08:00
Linus Torvalds
8c717b72de Merge branch 'core-debugobjects-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-debugobjects-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timer: Use debugobjects to catch deletion of uninitialized timers
  timer: Setup uninitialized timer with a stub callback
  debugobjects: Extend to assert that an object is initialized
  debugobjects: Be smarter about static objects
2012-01-06 07:53:34 -08:00
Eric Paris
fd77846152 security: remove the security_netlink_recv hook as it is equivalent to capable()
Once upon a time netlink was not sync and we had to get the effective
capabilities from the skb that was being received.  Today we instead get
the capabilities from the current task.  This has rendered the entire
purpose of the hook moot as it is now functionally equivalent to the
capable() call.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-05 18:53:01 -05:00
Eric Paris
69f594a389 ptrace: do not audit capability check when outputing /proc/pid/stat
Reading /proc/pid/stat of another process checks if one has ptrace permissions
on that process.  If one does have permissions it outputs some data about the
process which might have security and attack implications.  If the current
task does not have ptrace permissions the read still works, but those fields
are filled with inocuous (0) values.  Since this check and a subsequent denial
is not a violation of the security policy we should not audit such denials.

This can be quite useful to removing ptrace broadly across a system without
flooding the logs when ps is run or something which harmlessly walks proc.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
2012-01-05 18:53:00 -05:00
Eric Paris
f1c84dae0e capabilities: remove task_ns_* functions
task_ in the front of a function, in the security subsystem anyway, means
to me at least, that we are operating with that task as the subject of the
security decision.  In this case what it means is that we are using current as
the subject but we use the task to get the right namespace.  Who in the world
would ever realize that's what task_ns_capability means just by the name?  This
patch eliminates the task_ns functions entirely and uses the has_ns_capability
function instead.  This means we explicitly open code the ns in question in
the caller.  I think it makes the caller a LOT more clear what is going on.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
2012-01-05 18:52:59 -05:00
Eric Paris
d2a7009f0b capabitlies: ns_capable can use the cap helpers rather than lsm call
Just to reduce the number of places to change if we every change the LSM
hook, use the capability helpers internally when possible.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
2012-01-05 18:52:58 -05:00
Eric Paris
105ddf49cd capabilities: style only - move capable below ns_capable
Although the current code is fine for consistency this moves the capable
code below the function it calls in the c file.  It doesn't actually change
code.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
2012-01-05 18:52:57 -05:00
Eric Paris
7b61d64849 capabilites: introduce new has_ns_capabilities_noaudit
For consistency in interfaces, introduce a new interface called
has_ns_capabilities_noaudit.  It checks if the given task has the given
capability in the given namespace.  Use this new function by
has_capabilities_noaudit.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
2012-01-05 18:52:57 -05:00
Eric Paris
25e7570341 capabilities: call has_ns_capability from has_capability
Declare the more specific has_ns_capability first in the code and then call it
from has_capability.  The declaration reversal isn't stricty necessary since
they are both declared in header files, but it just makes sense to put more
specific functions first in the code.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
2012-01-05 18:52:56 -05:00
Eric Paris
2920a8409d capabilities: remove all _real_ interfaces
The name security_real_capable and security_real_capable_noaudit just don't
make much sense to me.  Convert them to use security_capable and
security_capable_noaudit.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
2012-01-05 18:52:55 -05:00
Eric Paris
b7e724d303 capabilities: reverse arguments to security_capable
security_capable takes ns, cred, cap.  But the LSM capable() hook takes
cred, ns, cap.  The capability helper functions also take cred, ns, cap.
Rather than flip argument order just to flip it back, leave them alone.
Heck, this should be a little faster since argument will be in the right
place!

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-01-05 18:52:53 -05:00
Li Zefan
0d19ea8665 cgroup: fix to allow mounting a hierarchy by name
If we mount a hierarchy with a specified name, the name is unique,
and we can use it to mount the hierarchy without specifying its
set of subsystem names. This feature is documented is
Documentation/cgroups/cgroups.txt section 2.3

Here's an example:

	# mount -t cgroup -o cpuset,name=myhier xxx /cgroup1
	# mount -t cgroup -o name=myhier xxx /cgroup2

But it was broken by commit 32a8cf235e
(cgroup: make the mount options parsing more accurate)

This fixes the regression.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
2012-01-05 09:59:46 -08:00
Russell King
2e0e943436 Merge branch 'devel-stable' into for-linus
Conflicts:
	arch/arm/kernel/setup.c
	arch/arm/mach-shmobile/board-kota2.c
2012-01-05 13:24:33 +00:00
Rafael J. Wysocki
c233523b3d Merge branch 'pm-sleep' into pm-for-linus
* pm-sleep:
  PM / Hibernate: Implement compat_ioctl for /dev/snapshot
2012-01-05 00:06:24 +01:00
Ben Hutchings
c336078bf6 PM / Hibernate: Implement compat_ioctl for /dev/snapshot
This allows uswsusp built for i386 to run on an x86_64 kernel (tested
with Debian package version 1.0+20110509-2).

References: http://bugs.debian.org/502816
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-01-05 00:05:55 +01:00
Oleg Nesterov
8a88951b58 ptrace: ensure JOBCTL_STOP_SIGMASK is not zero after detach
This is the temporary simple fix for 3.2, we need more changes in this
area.

1. do_signal_stop() assumes that the running untraced thread in the
   stopped thread group is not possible. This was our goal but it is
   not yet achieved: a stopped-but-resumed tracee can clone the running
   thread which can initiate another group-stop.

   Remove WARN_ON_ONCE(!current->ptrace).

2. A new thread always starts with ->jobctl = 0. If it is auto-attached
   and this group is stopped, __ptrace_unlink() sets JOBCTL_STOP_PENDING
   but JOBCTL_STOP_SIGMASK part is zero, this triggers WANR_ON(!signr)
   in do_jobctl_trap() if another debugger attaches.

   Change __ptrace_unlink() to set the artificial SIGSTOP for report.

   Alternatively we could change ptrace_init_task() to copy signr from
   current, but this means we can copy it for no reason and hide the
   possible similar problems.

Acked-by: Tejun Heo <tj@kernel.org>
Cc: <stable@kernel.org>		[3.1]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-04 15:01:59 -08:00
Oleg Nesterov
50b8d25748 ptrace: partially fix the do_wait(WEXITED) vs EXIT_DEAD->EXIT_ZOMBIE race
Test-case:

	int main(void)
	{
		int pid, status;

		pid = fork();
		if (!pid) {
			for (;;) {
				if (!fork())
					return 0;
				if (waitpid(-1, &status, 0) < 0) {
					printf("ERR!! wait: %m\n");
					return 0;
				}
			}
		}

		assert(ptrace(PTRACE_ATTACH, pid, 0,0) == 0);
		assert(waitpid(-1, NULL, 0) == pid);

		assert(ptrace(PTRACE_SETOPTIONS, pid, 0,
					PTRACE_O_TRACEFORK) == 0);

		do {
			ptrace(PTRACE_CONT, pid, 0, 0);
			pid = waitpid(-1, NULL, 0);
		} while (pid > 0);

		return 1;
	}

It fails because ->real_parent sees its child in EXIT_DEAD state
while the tracer is going to change the state back to EXIT_ZOMBIE
in wait_task_zombie().

The offending commit is 823b018e which moved the EXIT_DEAD check,
but in fact we should not blame it. The original code was not
correct as well because it didn't take ptrace_reparented() into
account and because we can't really trust ->ptrace.

This patch adds the additional check to close this particular
race but it doesn't solve the whole problem. We simply can't
rely on ->ptrace in this case, it can be cleared if the tracer
is multithreaded by the exiting ->parent.

I think we should kill EXIT_DEAD altogether, we should always
remove the soon-to-be-reaped child from ->children or at least
we should never do the DEAD->ZOMBIE transition. But this is too
complex for 3.2.

Reported-and-tested-by: Denys Vlasenko <vda.linux@googlemail.com>
Tested-by: Lukasz Michalik <lmi@ift.uni.wroc.pl>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: <stable@kernel.org>		[3.0+]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-04 15:01:59 -08:00
Dan Carpenter
305f3c8b20 cgroup: move assignement out of condition in cgroup_attach_proc()
Gcc complains about this: "kernel/cgroup.c:2179:4: warning: suggest
parentheses around assignment used as truth value [-Wparentheses]"

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2012-01-04 07:37:48 -08:00
Al Viro
93d3a10ef4 auditsc: propage umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:17 -05:00
Al Viro
2570ebbd1f switch kern_ipc_perm to umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:17 -05:00
Al Viro
df0a42837b switch mq_open() to umode_t 2012-01-03 22:55:16 -05:00
Al Viro
36fcb589e7 sysctl: use umode_t for table permissions
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:12 -05:00
Al Viro
a5e7ed3287 cgroup: propagate mode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:03 -05:00
Al Viro
f4ae40a6a5 switch debugfs to umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:56 -05:00
Al Viro
18bb1db3e7 switch vfs_mkdir() and ->mkdir() to umode_t
vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Al Viro
ff01bb4832 fs: move code out of buffer.c
Move invalidate_bdev, block_sync_page into fs/block_dev.c.  Export
kill_bdev as well, so brd doesn't have to open code it.  Reduce
buffer_head.h requirement accordingly.

Removed a rather large comment from invalidate_bdev, as it looked a bit
obsolete to bother moving.  The small comment replacing it says enough.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:07 -05:00
Al Viro
32dc730860 get rid of timer in kern/acct.c
... and clean it up a bit, while we are at it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:52:41 -05:00
Mandeep Singh Baines
f9fab10bbd hung_task: fix false positive during vfork
vfork parent uninterruptibly and unkillably waits for its child to
exec/exit. This wait is of unbounded length. Ignore such waits
in the hung_task detector.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Reported-by: Sasha Levin <levinsasha928@gmail.com>
LKML-Reference: <1325344394.28904.43.camel@lappy>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-03 16:14:32 -08:00
Al Viro
d36b691077 misc latin1 to utf8 conversions
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-01-02 13:04:55 +01:00
Hugh Dickins
e6780f7243 futex: Fix uninterruptible loop due to gate_area
It was found (by Sasha) that if you use a futex located in the gate
area we get stuck in an uninterruptible infinite loop, much like the
ZERO_PAGE issue.

While looking at this problem, PeterZ realized you'll get into similar
trouble when hitting any install_special_pages() mapping.  And are there
still drivers setting up their own special mmaps without page->mapping,
and without special VM or pte flags to make get_user_pages fail?

In most cases, if page->mapping is NULL, we do not need to retry at all:
Linus points out that even /proc/sys/vm/drop_caches poses no problem,
because it ends up using remove_mapping(), which takes care not to
interfere when the page reference count is raised.

But there is still one case which does need a retry: if memory pressure
called shmem_writepage in between get_user_pages_fast dropping page
table lock and our acquiring page lock, then the page gets switched from
filecache to swapcache (and ->mapping set to NULL) whatever the refcount.
Fault it back in to get the page->mapping needed for key->shared.inode.

Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-31 11:48:28 -08:00
Linus Torvalds
3b87487ac5 Revert "clockevents: Set noop handler in clockevents_exchange_device()"
This reverts commit de28f25e82.

It results in resume problems for various people. See for example

  http://thread.gmane.org/gmane.linux.kernel/1233033
  http://thread.gmane.org/gmane.linux.kernel/1233389
  http://thread.gmane.org/gmane.linux.kernel/1233159
  http://thread.gmane.org/gmane.linux.kernel/1227868/focus=1230877

and the fedora and ubuntu bug reports

  https://bugzilla.redhat.com/show_bug.cgi?id=767248
  https://bugs.launchpad.net/ubuntu/+source/linux/+bug/904569

which got bisected down to the stable version of this commit.

Reported-by: Jonathan Nieder <jrnieder@gmail.com>
Reported-by: Phil Miller <mille121@illinois.edu>
Reported-by: Philip Langdale <philipl@overt.org>
Reported-by: Tim Gardner <tim.gardner@canonical.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg KH <gregkh@suse.de>
Cc: stable@kernel.org    # for stable kernels that applied the original
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-30 13:24:40 -08:00
Rob Herring
93797d87d6 irq: check domain hwirq range for DT translate
A DT node may have more than 1 domain associated with it, so make sure
the hwirq number is within range when doing DT translation.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2011-12-28 08:26:06 -06:00
Frederic Weisbecker
7e3aa30ac8 cgroup: Remove task_lock() from cgroup_post_fork()
cgroup_post_fork() is protected between threadgroup_change_begin()
and threadgroup_change_end() against concurrent changes of the
child's css_set in cgroup_task_migrate(). Also the child can't
exit and call cgroup_exit() at this stage, this means it's css_set
can't be changed with init_css_set concurrently.

For these reasons, we don't need to hold task_lock() on the child
because it's css_set can only remain stable in this place.

Let's remove the lock there.

v2: Update comment to explain that we are safe against
cgroup_exit()

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Containers <containers@lists.linux-foundation.org>
Cc: Cgroups <cgroups@vger.kernel.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Menage <paul@paulmenage.org>
Cc: Mandeep Singh Baines <msb@chromium.org>
2011-12-27 09:05:20 -08:00
Kirill A. Shutemov
c6ca57500c cgroup: add sparse annotation to cgroup_iter_start() and cgroup_iter_end()
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2011-12-27 08:51:47 -08:00
Kirill A. Shutemov
1c6c3fad81 cgroup: mark cgroup_rmdir_waitq and cgroup_attach_proc() as static
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2011-12-27 08:51:46 -08:00
Avi Kivity
9e31905f29 Merge remote-tracking branch 'tip/perf/core' into kvm-updates/3.3
* tip/perf/core: (66 commits)
  perf, x86: Expose perf capability to other modules
  perf, x86: Implement arch event mask as quirk
  x86, perf: Disable non available architectural events
  jump_label: Provide jump_label_key initializers
  jump_label, x86: Fix section mismatch
  perf, core: Rate limit perf_sched_events jump_label patching
  perf: Fix enable_on_exec for sibling events
  perf: Remove superfluous arguments
  perf, x86: Prefer fixed-purpose counters when scheduling
  perf, x86: Fix event scheduler for constraints with overlapping counters
  perf, x86: Implement event scheduler helper functions
  perf: Avoid a useless pmu_disable() in the perf-tick
  x86/tools: Add decoded instruction dump mode
  x86: Update instruction decoder to support new AVX formats
  x86/tools: Fix insn_sanity message outputs
  x86/tools: Fix instruction decoder message output
  x86: Fix instruction decoder to handle grouped AVX instructions
  x86/tools: Fix Makefile to build all test tools
  perf test: Soft errors shouldn't stop the "Validate PERF_RECORD_" test
  perf test: Validate PERF_RECORD_ events and perf_sample fields
  ...

Signed-off-by: Avi Kivity <avi@redhat.com>

* commit 'b3d9468a8bd218a695e3a0ff112cd4efd27b670a': (66 commits)
  perf, x86: Expose perf capability to other modules
  perf, x86: Implement arch event mask as quirk
  x86, perf: Disable non available architectural events
  jump_label: Provide jump_label_key initializers
  jump_label, x86: Fix section mismatch
  perf, core: Rate limit perf_sched_events jump_label patching
  perf: Fix enable_on_exec for sibling events
  perf: Remove superfluous arguments
  perf, x86: Prefer fixed-purpose counters when scheduling
  perf, x86: Fix event scheduler for constraints with overlapping counters
  perf, x86: Implement event scheduler helper functions
  perf: Avoid a useless pmu_disable() in the perf-tick
  x86/tools: Add decoded instruction dump mode
  x86: Update instruction decoder to support new AVX formats
  x86/tools: Fix insn_sanity message outputs
  x86/tools: Fix instruction decoder message output
  x86: Fix instruction decoder to handle grouped AVX instructions
  x86/tools: Fix Makefile to build all test tools
  perf test: Soft errors shouldn't stop the "Validate PERF_RECORD_" test
  perf test: Validate PERF_RECORD_ events and perf_sample fields
  ...
2011-12-27 11:22:24 +02:00
Xiao Guangrong
a65cf5181a jump-label: export jump_label_inc/jump_label_dec
Export these two symbols, they will be used by KVM mmu audit

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27 11:22:04 +02:00
Rafael J. Wysocki
b7ba68c4a0 Merge branch 'pm-sleep' into pm-for-linus
* pm-sleep: (51 commits)
  PM: Drop generic_subsys_pm_ops
  PM / Sleep: Remove forward-only callbacks from AMBA bus type
  PM / Sleep: Remove forward-only callbacks from platform bus type
  PM: Run the driver callback directly if the subsystem one is not there
  PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
  PM / Sleep: Merge internal functions in generic_ops.c
  PM / Sleep: Simplify generic system suspend callbacks
  PM / Hibernate: Remove deprecated hibernation snapshot ioctls
  PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
  PM / Sleep: Recommend [un]lock_system_sleep() over using pm_mutex directly
  PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep()
  PM / Sleep: Make [un]lock_system_sleep() generic
  PM / Sleep: Use the freezer_count() functions in [un]lock_system_sleep() APIs
  PM / Freezer: Remove the "userspace only" constraint from freezer[_do_not]_count()
  PM / Hibernate: Replace unintuitive 'if' condition in kernel/power/user.c with 'else'
  Freezer / sunrpc / NFS: don't allow TASK_KILLABLE sleeps to block the freezer
  PM / Sleep: Unify diagnostic messages from device suspend/resume
  ACPI / PM: Do not save/restore NVS on Asus K54C/K54HR
  PM / Hibernate: Remove deprecated hibernation test modes
  PM / Hibernate: Thaw processes in SNAPSHOT_CREATE_IMAGE ioctl test path
  ...

Conflicts:
	kernel/kmod.c
2011-12-25 23:42:20 +01:00
Rafael J. Wysocki
3e68001bb1 Merge branch 'pm-misc' into pm-for-linus
* pm-misc:
  CPU: Add right qualifiers for alloc_frozen_cpus() and cpu_hotplug_pm_sync_init()
  PM / Usermodehelper: Cleanup remnants of usermodehelper_pm_callback()
2011-12-25 23:41:23 +01:00
Jamie Iles
c87fb57346 ARM: 7235/1: irqdomain: export irq_domain_simple_ops for !CONFIG_OF
irqdomain support is used in interrupt controller drivers that may not
have device tree support but only need the basic HW->Linux irq
translation.  Rather than having each of these implement their own IRQ
domain, allow them to use the simple ops.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rob Herring <robherring2@gmail.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-23 22:33:58 +00:00
Arun Sharma
1ac9bc6943 sched/tracing: Add a new tracepoint for sleeptime
If CONFIG_SCHEDSTATS is defined, the kernel maintains
information about how long the task was sleeping or
in the case of iowait, blocking in the kernel before
getting woken up.

This will be useful for sleep time profiling.

Note: this information is only provided for sched_fair.
Other scheduling classes may choose to provide this in
the future.

Note: the delay includes the time spent on the runqueue
as well.

Signed-off-by: Arun Sharma <asharma@fb.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1324512940-32060-2-git-send-email-asharma@fb.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-23 17:56:17 +01:00
Dave Jones
664dfa65e8 sched: Disable scheduler warnings during oopses
The panic-on-framebuffer code seems to cause a schedule
to occur during an oops. This causes a bunch of extra
spew as can be seen in:

   https://bugzilla.redhat.com/attachment.cgi?id=549230

Don't do scheduler debug checks when we are oopsing already.

Signed-off-by: Dave Jones <davej@redhat.com>
Link: http://lkml.kernel.org/r/20111222213929.GA4722@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-23 11:20:50 +01:00
Mandeep Singh Baines
892a2b90ba cgroup: only need to check oldcgrp==newgrp once
In cgroup_attach_proc it is now sufficient to only check that
oldcgrp==newcgrp once. Now that we are using threadgroup_lock()
during the migrations, oldcgrp will not change.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: containers@lists.linux-foundation.org
Cc: cgroups@vger.kernel.org
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Menage <paul@paulmenage.org>
2011-12-22 07:32:57 -08:00
Mandeep Singh Baines
b07ef77411 cgroup: remove redundant get/put of task struct
threadgroup_lock() guarantees that the target threadgroup will
remain stable - no new task will be added, no new PF_EXITING
will be set and exec won't happen.

Changes in V2:
* https://lkml.org/lkml/2011/12/20/369 (Tejun Heo)
  * Undo incorrect removal of get/put from attach_task_by_pid()
* Author
  * Remove a comment which is made stale by this change

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: containers@lists.linux-foundation.org
Cc: cgroups@vger.kernel.org
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Menage <paul@paulmenage.org>
2011-12-22 07:32:57 -08:00