This patch #ifdefs TINY_RCU kthreads out of the kernel unless RCU_BOOST=y,
thus eliminating context-switch overhead if RCU priority boosting has
not been configured.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Add event-trace markers to TREE_RCU kthreads to allow including these
kthread's CPU time in the utilization calculations.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Andi Kleen noticed that one of the RCU_BOOST data declarations was
out of sync with the definition. Move the declarations so that the
compiler can do the checking in the future.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
We now have kthreads only for flavors of RCU that support boosting,
so update the now-misleading comments accordingly.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Add a string to the rcu_batch_start() and rcu_batch_end() trace
messages that indicates the RCU type ("rcu_sched", "rcu_bh", or
"rcu_preempt"). The trace messages for the actual invocations
themselves are not marked, as it should be clear from the
rcu_batch_start() and rcu_batch_end() events before and after.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
In order to allow event tracing to distinguish between flavors of
RCU, we need those names in the relevant RCU data structures. TINY_RCU
has avoided them for memory-footprint reasons, so add them only if
CONFIG_RCU_TRACE=y.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit adds the trace_rcu_utilization() marker that is to be
used to allow postprocessing scripts compute RCU's CPU utilization,
give or take event-trace overhead. Note that we do not include RCU's
dyntick-idle interface because event tracing requires RCU protection,
which is not available in dyntick-idle mode.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
There was recently some controversy about the overhead of invoking RCU
callbacks. Add TRACE_EVENT()s to obtain fine-grained timings for the
start and stop of a batch of callbacks and also for each callback invoked.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The rcu_torture_boost() cleanup code destroyed debug-objects state before
waiting for the last RCU callback to be invoked, resulting in rare but
very real debug-objects warnings. Move the destruction to after the
waiting to fix this problem.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit eliminates the possibility of running TREE_PREEMPT_RCU
when SMP=n and of running TINY_RCU when PREEMPT=y. People who really
want these combinations can hand-edit init/Kconfig, but eliminating
them as choices for production systems reduces the amount of testing
required. It will also allow cutting out a few #ifdefs.
Note that running TREE_RCU and TINY_RCU on single-CPU systems using
SMP-built kernels is still supported.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
It has long been the case that the architecture must call nmi_enter()
and nmi_exit() rather than irq_enter() and irq_exit() in order to
permit RCU read-side critical sections in NMIs. Catch the documentation
up with reality.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Now that the RCU API contains synchronize_rcu_bh(), synchronize_sched(),
call_rcu_sched(), and rcu_bh_expedited()...
Make rcutorture test synchronize_rcu_bh(), getting rid of the old
rcu_bh_torture_synchronize() workaround. Similarly, make rcutorture test
synchronize_sched(), getting rid of the old sched_torture_synchronize()
workaround. Make rcutorture test call_rcu_sched() instead of wrappering
synchronize_sched(). Also add testing of rcu_bh_expedited().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Pull the code that waits for an RCU grace period into a single function,
which is then called by synchronize_rcu() and friends in the case of
TREE_RCU and TREE_PREEMPT_RCU, and from rcu_barrier() and friends in
the case of TINY_RCU and TINY_PREEMPT_RCU.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
rcutree.c defines rcu_cpu_kthread_cpu as int, not unsigned int,
so the extern has to follow that.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Update rcutorture documentation to account for boosting, new types of
RCU torture testing that have been added over the past few years, and
the memory-barrier testing that was added an embarrassingly long time
ago.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Take a first step towards untangling Linux kernel header files by
placing the struct rcu_head definition into include/linux/types.h
and including include/linux/types.h in include/linux/rcupdate.h
where struct rcu_head used to be defined. The actual inclusion point
for include/linux/types.h is with the rest of the #include directives
rather than at the point where struct rcu_head used to be defined,
as suggested by Mathieu Desnoyers.
Once this is in place, then header files that need only rcu_head
can include types.h rather than rcupdate.h.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Long ago, using TREE_RCU with PREEMPT would result in "scheduling
while atomic" diagnostics if you blocked in an RCU read-side critical
section. However, PREEMPT now implies TREE_PREEMPT_RCU, which defeats
this diagnostic. This commit therefore adds a replacement diagnostic
based on PROVE_RCU.
Because rcu_lockdep_assert() and lockdep_rcu_dereference() are now being
used for things that have nothing to do with rcu_dereference(), rename
lockdep_rcu_dereference() to lockdep_rcu_suspicious() and add a third
argument that is a string indicating what is suspicious. This third
argument is passed in from a new third argument to rcu_lockdep_assert().
Update all calls to rcu_lockdep_assert() to add an informative third
argument.
Also, add a pair of rcu_lockdep_assert() calls from within
rcu_note_context_switch(), one complaining if a context switch occurs
in an RCU-bh read-side critical section and another complaining if a
context switch occurs in an RCU-sched read-side critical section.
These are present only if the PROVE_RCU kernel parameter is enabled.
Finally, fix some checkpatch whitespace complaints in lockdep.c.
Again, you must enable PROVE_RCU to see these new diagnostics. But you
are enabling PROVE_RCU to check out new RCU uses in any case, aren't you?
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Call out the RCU_TRACE information that is provided only in kernels
built with RCU_BOOST.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
There are a number of cases where the RCU can find additional work
for the per-CPU kthread within the context of that per-CPU kthread.
In such cases, the per-CPU kthread is already running, so attempting
to wake itself up does nothing except waste CPU cycles. This commit
therefore checks to see if it is in the per-CPU kthread context,
omitting the wakeup in this case.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Commit a26ac2455f (move TREE_RCU from softirq to kthread) added
per-CPU kthreads. However, kthread creation uses kthread_create(), which
can put the kthread's stack and task struct on the wrong NUMA node.
Therefore, use kthread_create_on_node() instead of kthread_create()
so that the stacks and task structs are placed on the correct NUMA node.
A similar change was carried out in commit 94dcf29a11 (kthread:
use kthread_create_on_node()).
Also change rcutorture's priority-boost-test kthread creation.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Tejun Heo <tj@kernel.org>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Andi Kleen <ak@linux.intel.com>
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* 'for-linus' of git://github.com/tiwai/sound:
ASoC: ssm2602: Re-enable oscillator after suspend
ALSA: usb-audio: Check for possible chip NULL pointer before clearing probing flag
ALSA: hda/realtek - Don't detect LO jack when identical with HP
ALSA: hda/realtek - Avoid bogus HP-pin assignment
ALSA: HDA: No power nids on 92HD93
ASoC: omap-mcbsp: Do not attempt to change DAI sysclk if stream is active
That flag no longer makes sense, since we don't look up automount points
as eagerly any more. Additionally, it turns out that the NO_AUTOMOUNT
handling was buggy to begin with: it would avoid automounting even for
cases where we really *needed* to do the automount handling, and could
return ENOENT for autofs entries that hadn't been instantiated yet.
With our new non-eager automount semantics, one discussion has been
about adding a AT_AUTOMOUNT flag to vfs_fstatat (and thus the
newfstatat() and fstatat64() system calls), but it's probably not worth
it: you can always force at least directory automounting by simply
adding the final '/' to the filename, which works for *all* of the stat
family system calls, old and new.
So AT_NO_AUTOMOUNT (and thus LOOKUP_NO_AUTOMOUNT) really were just a
result of our bad default behavior.
Acked-by: Ian Kent <raven@themaw.net>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently the the internal oscillator is powered down when entering BIAS_OFF
state, but not re-enabled when going back to BIAS_STANDBY. As a result the
CODEC will stop working after suspend if the internal oscillator is used to
generate the sysclock signal. This patch fixes it by clearing the appropriate
bit in the power down register when the CODEC is re-enabled.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org
The concensus seems to be that system calls such as stat() etc should
not trigger an automount. Neither should the l* versions.
This patch therefore adds a LOOKUP_AUTOMOUNT flag to tag those lookups
that _should_ trigger an automount on the last path element.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[ Edited to leave out the cases that are already covered by LOOKUP_OPEN,
LOOKUP_DIRECTORY and LOOKUP_CREATE - all of which also fundamentally
force automounting for their own reasons - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since we've now turned around and made LOOKUP_FOLLOW *not* force an
automount, we want to add the ability to force an automount event on
lookup even if we don't happen to have one of the other flags that force
it implicitly (LOOKUP_OPEN, LOOKUP_DIRECTORY, LOOKUP_PARENT..)
Most cases will never want to use this, since you'd normally want to
delay automounting as long as possible, which usually implies
LOOKUP_OPEN (when we open a file or directory, we really cannot avoid
the automount any more).
But Trond argued sufficiently forcefully that at a minimum bind mounting
a file and quotactl will want to force the automount lookup. Some other
cases (like nfs_follow_remote_path()) could use it too, although
LOOKUP_DIRECTORY would work there as well.
This commit just adds the flag and logic, no users yet, though. It also
doesn't actually touch the LOOKUP_NO_AUTOMOUNT flag that is related, and
was made irrelevant by the same change that made us not follow on
LOOKUP_FOLLOW.
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg KH <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The sclk_cam clocks are now controlled by the top level FIMC media
device driver bound to "s5p-fimc-md" platform device.
Rename sclk_cam clocks so they accessible by the corresponding
driver.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The sclk_cam clocks are now controlled by the top level FIMC media
device driver bound to "s5p-fimc-md" platform device.
Rename sclk_cam clocks so they accessible by the corresponding
driver.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
* 'hwmon-for-linus' of git://github.com/groeck/linux:
hwmon: (coretemp) remove struct platform_data * parameter from create_core_data()
hwmon: (coretemp) constify static data
hwmon: (coretemp) don't use kernel assigned CPU number as platform device ID
hwmon: (ds620) Fix handling of negative temperatures
hwmon: (w83791d) rename prototype parameter from 'register' to 'reg'
hwmon: (coretemp) Don't use threshold registers for tempX_max
hwmon: (coretemp) Let the user force TjMax
hwmon: (coretemp) Drop duplicate function get_pkg_tjmax
* 'fixes' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm:
ARM: 7099/1: futex: preserve oldval in SMP __futex_atomic_op
ARM: dma-mapping: free allocated page if unable to map
ARM: fix vmlinux.lds.S discarding sections
ARM: nommu: fix warning with checksyscalls.sh
ARM: 7091/1: errata: D-cache line maintenance operation by MVA may not succeed
Commit b7ab83e (PM: Use spinlock instead of mutex in clock
management functions) introduced a regression causing clocks_mutex
to be acquired under a spinlock. This happens because
pm_clk_suspend() and pm_clk_resume() call pm_clk_acquire() under
pcd->lock, but pm_clk_acquire() executes clk_get() which causes
clocks_mutex to be acquired. Similarly, __pm_clk_remove(),
executed under pcd->lock, calls clk_put(), which also causes
clocks_mutex to be acquired.
To fix those problems make pm_clk_add() call pm_clk_acquire(), so
that pm_clk_suspend() and pm_clk_resume() don't have to do that.
Change pm_clk_remove() and pm_clk_destroy() to separate
modifications of the pcd->clock_list list from the actual removal of
PM clock entry objects done by __pm_clk_remove().
Reported-and-tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Before clearing the probing flag in the error exit path, check that the
chip pointer is not NULL.
Signed-off-by: Thomas Pfaff <tpfaff@gmx.net>
Cc: <stable@kernel.org> [2.6.39+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The spec->autocfg.line_out_pins[] may contain the same pins as hp_pins[]
depending on the configuration. When they are identical, detecting the
line_jack_present flag screws up the auto-mute because alc_line_automute()
is called unconditionally at initialization while it won't be triggered
by unsol events, thus the old line_jack_present flag is kept for the
whole run.
For fixing this buggy behavior, the driver needs to check whether the
line-outs are really individual, and skip if same as headphone jacks.
Reference: https://bugzilla.novell.com/show_bug.cgi?id=716104
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The SMP implementation of __futex_atomic_op clobbers oldval with the
status flag from the exclusive store. This causes it to always read as
zero when performing the FUTEX_OP_CMP_* operation.
This patch updates the ARM __futex_atomic_op implementations to take a
tmp argument, allowing us to store the strex status flag without
overwriting the register containing oldval.
Cc: stable@kernel.org
Reported-by: Minho Ban <mhban@samsung.com>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When the headphone pin is assigned as primary output to line_out_pins[],
the automatic HP-pin assignment by ASSID must be suppressed. Otherwise
a wrong pin might be assigned to the headphone and breaks the auto-mute.
Reference: https://bugzilla.novell.com/show_bug.cgi?id=716104
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>
If the attempt to map a page for DMA fails (eg, because we're out of
mapping space) then we must not hold on to the page we allocated for
DMA - doing so will result in a memory leak.
Cc: <stable@kernel.org>
Reported-by: Bryan Phillippe <bp@darkforest.org>
Tested-by: Bryan Phillippe <bp@darkforest.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Loop iterator value after terminating list_for_each_entry()
is not NULL. This patch fixes incorrect iterator usage in
GPIO interrupt code for SAMSUNG S5P platforms.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The changed statement should set the old armdiv bits to 0
and not everything else, before setting the new value.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
If PTRACE_LISTEN fails after lock_task_sighand() it doesn't drop ->siglock.
Reported-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Src2CL decode (used for double width shifts) erronously decodes only bit 3
of %rcx, instead of bits 7:0.
Fix by decoding %cl in its entirety.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
__update_clear_spte_slow should return original spte while the
current code returns low half of original spte combined with high
half of new spte.
Signed-off-by: Zhao Jin <cronozhj@gmail.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This patch is necessary to make internal speakers work on this chip.
Cc: stable@kernel.org
BugLink: http://bugs.launchpad.net/bugs/854468
Tested-by: Alex Wolfson <alex.wolfson@canonical.com>
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
* 'spi/merge' of git://git.secretlab.ca/git/linux-2.6:
spi: Fix WARN when removing spi-fsl-spi module
spi/imx: Fix spi-imx when the hardware SPI chipselects are used
If CPM mode is not used, the fsl_dummy_rx variable is never allocated. When
the cleanup attempts to free it, the reference count is zero and a WARN is
generated. The same CPM mode check used in the initialize is applied to the
free as well.
Tested on 2.6.33 with the previous spi_mpc8xxx driver. The renamed
spi-fsl-spi driver looks to have the same problem.
Signed-off-by: Jeff Harris <jeff_harris@kentrox.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
sector_t can be different types, so cast it to its largest possible
type.
drivers/scsi/qla2xxx/qla_isr.c:1509:5: warning: format '%lx' expects type 'long unsigned int', but argument 5 has type 'sector_t'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SCSI_ISCI needs to select SCSI_SAS_HOST_SMP to ensure that all
needed symbols are available to it.
Fixes this build error:
ERROR: "try_test_sas_gpio_gp_bit" [drivers/scsi/isci/isci.ko] undefined!
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
