Commit Graph

617 Commits

Author SHA1 Message Date
Grant Likely
5269a9ab7d irq_domain: fix type mismatch in debugfs output format
sizeof(void*) returns an unsigned long, but it was being used as a width parameter to a "%-*s" format string which requires an int.  On 64 bit platforms this causes a type mismatch:

    linux/kernel/irq/irqdomain.c:575: warning: field width should have type
    'int', but argument 6 has type 'long unsigned int'

This change casts the size to an int so printf gets the right data type.

Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>
2012-04-12 16:25:48 -06:00
Grant Likely
6fa6c8e25e irq_domain: Move irq_virq_count into NOMAP revmap
This patch replaces the old global setting of irq_virq_count that is only
used by the NOMAP mapping and instead uses a revmap_data property so that
the maximum NOMAP allocation can be set per NOMAP irq_domain.

There is exactly one user of irq_virq_count in-tree right now: PS3.
Also, irq_virq_count is only useful for the NOMAP mapping.  So,
instead of having a single global irq_virq_count values, this change
drops it entirely and added a max_irq argument to irq_domain_add_nomap().
That makes it a property of an individual nomap irq domain instead of
a global system settting.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
2012-04-12 00:37:48 -06:00
Grant Likely
15e06bf64f irqdomain: Fix debugfs formatting
This patch fixes the irq_domain_mapping debugfs output to pad pointer
values with leading zeros so that pointer values are displayed
correctly.  Otherwise you get output similar to "0x 5e0000000000000".
Also, when the irq_domain is set to 'null'

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
2012-04-11 01:01:45 -06:00
Mika Westerberg
ac5830a33f irq_domain: correct the debugfs file name
The actual name of the irq_domain mapping debugfs file is
"irq_domain_mapping" not "virq_mapping".

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-04-10 22:39:17 -06:00
David Daney
5b7526e3a6 irq/irq_domain: Quit ignoring error returns from irq_alloc_desc_from().
In commit 4bbdd45a (irq_domain/powerpc: eliminate irq_map; use
irq_alloc_desc() instead) code was added that ignores error returns
from irq_alloc_desc_from() by (silently) casting the return value to
unsigned.  The negitive value error return now suddenly looks like a
valid irq number.

Commits cc79ca69 (irq_domain: Move irq_domain code from powerpc to
kernel/irq) and 1bc04f2c (irq_domain: Add support for base irq and
hwirq in legacy mappings) move this code to its current location in
irqdomain.c

The result of all of this is a null pointer dereference OOPS if one of
the error cases is hit.

The fix: Don't cast away the negativeness of the return value and then
check for errors.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
[grant.likely: dropped addition of new 'irq' variable]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-04-10 22:39:16 -06:00
Linus Torvalds
f558c27238 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull genirq updates from Thomas Gleixner.

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Adjust irq thread affinity on IRQ_SET_MASK_OK_NOCOPY return value
  genirq: Respect NUMA node affinity in setup_irq_irq affinity()
  genirq: Get rid of unneeded force parameter in irq_finalize_oneshot()
  genirq: Minor readablity improvement in irq_wake_thread()
2012-03-30 18:08:05 -07:00
Jiang Liu
f5cb92ac82 genirq: Adjust irq thread affinity on IRQ_SET_MASK_OK_NOCOPY return value
irq_move_masked_irq() checks the return code of
chip->irq_set_affinity() only for 0, but IRQ_SET_MASK_OK_NOCOPY is
also a valid return code, which is there to avoid a redundant copy of
the cpumask. But in case of IRQ_SET_MASK_OK_NOCOPY we not only avoid
the redundant copy, we also fail to adjust the thread affinity of an
eventually threaded interrupt handler.

Handle IRQ_SET_MASK_OK (==0) and IRQ_SET_MASK_OK_NOCOPY(==1) return
values correctly by checking the valid return values seperately.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Keping Chen <chenkeping@huawei.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1333120296-13563-2-git-send-email-jiang.liu@huawei.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-30 23:13:46 +02:00
Linus Torvalds
12679a2d7e Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull more ARM updates from Russell King.

This got a fair number of conflicts with the <asm/system.h> split, but
also with some other sparse-irq and header file include cleanups.  They
all looked pretty trivial, though.

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (59 commits)
  ARM: fix Kconfig warning for HAVE_BPF_JIT
  ARM: 7361/1: provide XIP_VIRT_ADDR for no-MMU builds
  ARM: 7349/1: integrator: convert to sparse irqs
  ARM: 7259/3: net: JIT compiler for packet filters
  ARM: 7334/1: add jump label support
  ARM: 7333/2: jump label: detect %c support for ARM
  ARM: 7338/1: add support for early console output via semihosting
  ARM: use set_current_blocked() and block_sigmask()
  ARM: exec: remove redundant set_fs(USER_DS)
  ARM: 7332/1: extract out code patch function from kprobes
  ARM: 7331/1: extract out insn generation code from ftrace
  ARM: 7330/1: ftrace: use canonical Thumb-2 wide instruction format
  ARM: 7351/1: ftrace: remove useless memory checks
  ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path
  ARM: Versatile Express: add NO_IOPORT
  ARM: get rid of asm/irq.h in asm/prom.h
  ARM: 7319/1: Print debug info for SIGBUS in user faults
  ARM: 7318/1: gic: refactor irq_start assignment
  ARM: 7317/1: irq: avoid NULL check in for_each_irq_desc loop
  ARM: 7315/1: perf: add support for the Cortex-A7 PMU
  ...
2012-03-29 16:53:48 -07:00
Grant Likely
092b2fb076 irqdomain: Remove powerpc dependency from debugfs file
The debugfs code is really generic for all platforms.  This patch removes the
powerpc-specific directory reference and makes it available to all
architectures.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-03-29 14:31:02 -06:00
Prarit Bhargava
241fc640be genirq: Respect NUMA node affinity in setup_irq_irq affinity()
We respect node affinity of devices already in the irq descriptor
allocation, but we ignore it for the initial interrupt affinity
setup, so the interrupt might be routed to a different node.

Restrict the default affinity mask to the node on which the irq
descriptor is allocated.

[ tglx: Massaged changelog ]

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/1332788538-17425-1-git-send-email-prarit@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29 11:31:53 +02:00
Alexander Gordeev
f3f79e38d5 genirq: Get rid of unneeded force parameter in irq_finalize_oneshot()
The only place irq_finalize_oneshot() is called with force parameter set
is the threaded handler error exit path. But IRQTF_RUNTHREAD is dropped
at this point and irq_wake_thread() is not going to set it again,
since PF_EXITING is set for this thread already. So irq_finalize_oneshot()
will drop the threads bit in threads_oneshot anyway and hence the force
parameter is superfluous.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120321162234.GP24806@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29 11:31:53 +02:00
Alexander Gordeev
69592db298 genirq: Minor readablity improvement in irq_wake_thread()
exit_irq_thread() clears IRQTF_RUNTHREAD flag and drops the thread's bit in
desc->threads_oneshot then. The bit must not be set again in between and it
does not, since irq_wake_thread() sees PF_EXITING flag first and returns.

Due to above the order or checking PF_EXITING and IRQTF_RUNTHREAD flags in
irq_wake_thread() is important. This change just makes it more visible in the
source code.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120321162212.GO24806@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29 11:31:52 +02:00
Linus Torvalds
c207f3a431 Generialize powerpc's irq_host as irq_domain
This branch takes the PowerPC irq_host infrastructure (reverse mapping
 from Linux IRQ numbers to hardware irq numbering), generalizes it,
 renames it to irq_domain, and makes it available to all architectures.
 
 Originally the plan has been to create an all-new irq_domain
 implementation which addresses some of the powerpc shortcomings such
 as not handling 1:1 mappings well, but doing that proved to be far
 more difficult and invasive than generalizing the working code and
 refactoring it in-place.  So, this branch rips out the 'new'
 irq_domain and replaces it with the modified powerpc version (in a
 fully bisectable way of course).  It converts all users over to the
 new API and makes irq_domain selectable on any architecture.
 
 No architecture is forced to enable irq_domain, but the infrastructure
 is required for doing OpenFirmware style irq translations.  It will
 even work on SPARC even though SPARC has it's own mechanism for
 translating irqs at boot time.  MIPS, microblaze, embedded x86 and c6x
 are converted too.
 
 The resulting irq_domain code is probably still too verbose and can be
 optimized more, but that can be done incrementally and is a task for
 follow-on patches.
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Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6

Pull irq_domain support for all architectures from Grant Likely:
 "Generialize powerpc's irq_host as irq_domain

  This branch takes the PowerPC irq_host infrastructure (reverse mapping
  from Linux IRQ numbers to hardware irq numbering), generalizes it,
  renames it to irq_domain, and makes it available to all architectures.

  Originally the plan has been to create an all-new irq_domain
  implementation which addresses some of the powerpc shortcomings such
  as not handling 1:1 mappings well, but doing that proved to be far
  more difficult and invasive than generalizing the working code and
  refactoring it in-place.  So, this branch rips out the 'new'
  irq_domain and replaces it with the modified powerpc version (in a
  fully bisectable way of course).  It converts all users over to the
  new API and makes irq_domain selectable on any architecture.

  No architecture is forced to enable irq_domain, but the infrastructure
  is required for doing OpenFirmware style irq translations.  It will
  even work on SPARC even though SPARC has it's own mechanism for
  translating irqs at boot time.  MIPS, microblaze, embedded x86 and c6x
  are converted too.

  The resulting irq_domain code is probably still too verbose and can be
  optimized more, but that can be done incrementally and is a task for
  follow-on patches."

* tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6: (31 commits)
  dt: fix twl4030 for non-dt compile on x86
  mfd: twl-core: Add IRQ_DOMAIN dependency
  devicetree: Add empty of_platform_populate() for !CONFIG_OF_ADDRESS (sparc)
  irq_domain: Centralize definition of irq_dispose_mapping()
  irq_domain/mips: Allow irq_domain on MIPS
  irq_domain/x86: Convert x86 (embedded) to use common irq_domain
  ppc-6xx: fix build failure in flipper-pic.c and hlwd-pic.c
  irq_domain/microblaze: Convert microblaze to use irq_domains
  irq_domain/powerpc: Replace custom xlate functions with library functions
  irq_domain/powerpc: constify irq_domain_ops
  irq_domain/c6x: Use library of xlate functions
  irq_domain/c6x: constify irq_domain structures
  irq_domain/c6x: Convert c6x to use generic irq_domain support.
  irq_domain: constify irq_domain_ops
  irq_domain: Create common xlate functions that device drivers can use
  irq_domain: Remove irq_domain_add_simple()
  irq_domain: Remove 'new' irq_domain in favour of the ppc one
  mfd: twl-core.c: Fix the number of interrupts managed by twl4030
  of/address: add empty static inlines for !CONFIG_OF
  irq_domain: Add support for base irq and hwirq in legacy mappings
  ...
2012-03-21 10:27:19 -07:00
Linus Torvalds
9c2b957db1 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events changes for v3.4 from Ingo Molnar:

 - New "hardware based branch profiling" feature both on the kernel and
   the tooling side, on CPUs that support it.  (modern x86 Intel CPUs
   with the 'LBR' hardware feature currently.)

   This new feature is basically a sophisticated 'magnifying glass' for
   branch execution - something that is pretty difficult to extract from
   regular, function histogram centric profiles.

   The simplest mode is activated via 'perf record -b', and the result
   looks like this in perf report:

	$ perf record -b any_call,u -e cycles:u branchy

	$ perf report -b --sort=symbol
	    52.34%  [.] main                   [.] f1
	    24.04%  [.] f1                     [.] f3
	    23.60%  [.] f1                     [.] f2
	     0.01%  [k] _IO_new_file_xsputn    [k] _IO_file_overflow
	     0.01%  [k] _IO_vfprintf_internal  [k] _IO_new_file_xsputn
	     0.01%  [k] _IO_vfprintf_internal  [k] strchrnul
	     0.01%  [k] __printf               [k] _IO_vfprintf_internal
	     0.01%  [k] main                   [k] __printf

   This output shows from/to branch columns and shows the highest
   percentage (from,to) jump combinations - i.e.  the most likely taken
   branches in the system.  "branches" can also include function calls
   and any other synchronous and asynchronous transitions of the
   instruction pointer that are not 'next instruction' - such as system
   calls, traps, interrupts, etc.

   This feature comes with (hopefully intuitive) flat ascii and TUI
   support in perf report.

 - Various 'perf annotate' visual improvements for us assembly junkies.
   It will now recognize function calls in the TUI and by hitting enter
   you can follow the call (recursively) and back, amongst other
   improvements.

 - Multiple threads/processes recording support in perf record, perf
   stat, perf top - which is activated via a comma-list of PIDs:

	perf top -p 21483,21485
	perf stat -p 21483,21485 -ddd
	perf record -p 21483,21485

 - Support for per UID views, via the --uid paramter to perf top, perf
   report, etc.  For example 'perf top --uid mingo' will only show the
   tasks that I am running, excluding other users, root, etc.

 - Jump label restructurings and improvements - this includes the
   factoring out of the (hopefully much clearer) include/linux/static_key.h
   generic facility:

	struct static_key key = STATIC_KEY_INIT_FALSE;

	...

	if (static_key_false(&key))
	        do unlikely code
	else
	        do likely code

	...
	static_key_slow_inc();
	...
	static_key_slow_inc();
	...

   The static_key_false() branch will be generated into the code with as
   little impact to the likely code path as possible.  the
   static_key_slow_*() APIs flip the branch via live kernel code patching.

   This facility can now be used more widely within the kernel to
   micro-optimize hot branches whose likelihood matches the static-key
   usage and fast/slow cost patterns.

 - SW function tracer improvements: perf support and filtering support.

 - Various hardenings of the perf.data ABI, to make older perf.data's
   smoother on newer tool versions, to make new features integrate more
   smoothly, to support cross-endian recording/analyzing workflows
   better, etc.

 - Restructuring of the kprobes code, the splitting out of 'optprobes',
   and a corner case bugfix.

 - Allow the tracing of kernel console output (printk).

 - Improvements/fixes to user-space RDPMC support, allowing user-space
   self-profiling code to extract PMU counts without performing any
   system calls, while playing nice with the kernel side.

 - 'perf bench' improvements

 - ... and lots of internal restructurings, cleanups and fixes that made
   these features possible.  And, as usual this list is incomplete as
   there were also lots of other improvements

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits)
  perf report: Fix annotate double quit issue in branch view mode
  perf report: Remove duplicate annotate choice in branch view mode
  perf/x86: Prettify pmu config literals
  perf report: Enable TUI in branch view mode
  perf report: Auto-detect branch stack sampling mode
  perf record: Add HEADER_BRANCH_STACK tag
  perf record: Provide default branch stack sampling mode option
  perf tools: Make perf able to read files from older ABIs
  perf tools: Fix ABI compatibility bug in print_event_desc()
  perf tools: Enable reading of perf.data files from different ABI rev
  perf: Add ABI reference sizes
  perf report: Add support for taken branch sampling
  perf record: Add support for sampling taken branch
  perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK
  x86/kprobes: Split out optprobe related code to kprobes-opt.c
  x86/kprobes: Fix a bug which can modify kernel code permanently
  x86/kprobes: Fix instruction recovery on optimized path
  perf: Add callback to flush branch_stack on context switch
  perf: Disable PERF_SAMPLE_BRANCH_* when not supported
  perf/x86: Add LBR software filter support for Intel CPUs
  ...
2012-03-20 10:29:15 -07:00
Thomas Gleixner
e04268b0ef genirq: Remove paranoid warnons and bogus fixups
Alexander pointed out that the warnons in the regular exit path are
bogus and the thread_mask one actually could be triggered when
__setup_irq() hands out that thread_mask again after __free_irq()
dropped irq_desc->lock.

Thinking more about it, neither IRQTF_RUNTHREAD nor the bit in
thread_mask can be set as this is the regular exit path. We come here
due to:
	__free_irq()
	   remove action from desc
	   synchronize_irq()
	   kthread_stop()

So synchronize_irq() makes sure that the thread finished running and
cleaned up both the thread_active count and thread_mask. After that
point nothing can set IRQTF_RUNTHREAD on this action. So the warnons
and the cleanups are pointless.

Reported-by: Alexander Gordeev <agordeev@redhat.com>
Cc: Ido Yariv <ido@wizery.com>
Link: http://lkml.kernel.org/r/20120315190755.GA6732@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-16 11:27:28 +01:00
Ido Yariv
7140ea1980 genirq: Flush the irq thread on synchronization
The current implementation does not always flush the threaded handler
when disabling the irq. In case the irq handler was called, but the
threaded handler hasn't started running yet, the interrupt will be
flagged as pending, and the handler will not run. This implementation
has some issues:

First, if the interrupt is a wake source and flagged as pending, the
system will not be able to suspend.

Second, when quickly disabling and re-enabling the irq, the threaded
handler might continue to run after the irq is re-enabled without the
irq handler being called first. This might be an unexpected behavior.

In addition, it might be counter-intuitive that the threaded handler
will not be called even though the irq handler was called and returned
IRQ_WAKE_THREAD.

Fix this by always waiting for the threaded handler to complete in
synchronize_irq().

[ tglx: Massaged comments, added WARN_ONs and the missing
  	IRQTF_RUNTHREAD check in exit_irq_thread() ]

Signed-off-by: Ido Yariv <ido@wizery.com>
Link: http://lkml.kernel.org/r/1322843052-7166-1-git-send-email-ido@wizery.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-14 11:56:20 +01:00
Thomas Gleixner
df8d291f28 Merge branch 'linus' into irq/core
Reason: Get upstream fixes integrated before further modifications.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-13 16:35:16 +01:00
Ingo Molnar
35239e23c6 Merge branch 'perf/urgent' into perf/core
Merge reason: We are going to queue up a dependent patch.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12 20:44:11 +01:00
Alexander Gordeev
5234ffb9f7 genirq: Get rid of unnecessary IRQTF_DIED flag
Currently IRQTF_DIED flag is set when a IRQ thread handler calls do_exit()
But also PF_EXITING per process flag gets set when a thread exits. This
fix eliminates the duplicate by using PF_EXITING flag.

Also, there is a race condition in exit_irq_thread(). In case a thread's
bit is cleared in desc->threads_oneshot (and the IRQ line gets unmasked),
but before IRQTF_DIED flag is set, a new interrupt might come in and set
just cleared bit again, this time forever. This fix throws IRQTF_DIED flag
away, eliminating the race as a result.

[ tglx: Test THREAD_EXITING first as suggested by Oleg ]

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120309135958.GD2114@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09 17:19:09 +01:00
Alexander Gordeev
05d74efa3c genirq: No need to check IRQTF_DIED before stopping a thread handler
Since 63706172f3 kthread_stop() is not
afraid of dead kernel threads. So no need to check if a thread is
alive before stopping it. These checks still were racy.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120309135939.GC2114@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09 17:19:08 +01:00
Alexander Gordeev
4bcdf1d0b6 genirq: Get rid of unnecessary irqaction field in task_struct
When a new thread handler is created, an irqaction is passed to it as
data. Not only that irqaction is stored in task_struct by the handler
for later use, but also a structure associated with the kernel thread
keeps this value as long as the thread exists.

This fix kicks irqaction out off task_struct. Yes, I introduce new bit
field. But it allows not only to eliminate the duplicate, but also
shortens size of task_struct.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120309135925.GB2114@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09 17:19:08 +01:00
Alexander Gordeev
540b60e24f genirq: Fix incorrect check for forced IRQ thread handler
We do not want a bitwise AND between boolean operands

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20120309135912.GA2114@dhcp-26-207.brq.redhat.com
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09 17:19:08 +01:00
Thomas Gleixner
52abb700e1 genirq: Clear action->thread_mask if IRQ_ONESHOT is not set
Xommit ac5637611(genirq: Unmask oneshot irqs when thread was not woken)
fails to unmask when a !IRQ_ONESHOT threaded handler is handled by
handle_level_irq.

This happens because thread_mask is or'ed unconditionally in
irq_wake_thread(), but for !IRQ_ONESHOT interrupts never cleared.  So
the check for !desc->thread_active fails and keeps the interrupt
disabled.

Keep the thread_mask zero for !IRQ_ONESHOT interrupts.

Document the thread_mask magic while at it.

Reported-and-tested-by: Sven Joachim <svenjoac@gmx.de>
Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-06 16:46:39 -08:00
Russell King
a09b659cd6 genirq: Fix long-term regression in genirq irq_set_irq_type() handling
In 2008, commit 0c5d1eb77a ("genirq: record trigger type") modified the
way set_irq_type() handles the 'no trigger' condition.  However, this has
an adverse effect on PCMCIA support on Intel StrongARM and probably PXA
platforms.

PCMCIA has several status signals on the socket which can trigger
interrupts; some of these status signals depend on the card's mode
(whether it is configured in memory or IO mode).  For example, cards have
a 'Ready/IRQ' signal: in memory mode, this provides an indication to
PCMCIA that the card has finished its power up initialization.  In IO
mode, it provides the device interrupt signal.  Other status signals
switch between on-board battery status and loud speaker output.

In classical PCMCIA implementations, where you have a specific socket
controller, the controller provides a method to mask interrupts from the
socket, and importantly ignore any state transitions on the pins which
correspond with interrupts once masked.  This masking prevents unwanted
events caused by the removal and application of socket power being
forwarded.

However, on platforms where there is no socket controller, the PCMCIA
status and interrupt signals are routed to standard edge-triggered GPIOs. 
These GPIOs can be configured to interrupt on rising edge, falling edge,
or never.  This is where the problems start.

Edge triggered interrupts are required to record events while disabled via
the usual methods of {free,request,disable,enable}_irq() to prevent
problems with dropped interrupts (eg, the 8390 driver uses disable_irq()
to defer the delivery of interrupts).  As a result, these interfaces can
not be used to implement the desired behaviour.

The side effect of this is that if the 'Ready/IRQ' GPIO is disabled via
disable_irq() on suspend, and enabled via enable_irq() after resume, we
will record the state transitions caused by powering events as valid
interrupts, and foward them to the card driver, which may attempt to
access a card which is not powered up.

This leads delays resume while drivers spin in their interrupt handlers,
and complaints from drivers before they realize what's happened.

Moreover, in the case of the 'Ready/IRQ' signal, this is requested and
freed by the card driver itself; the PCMCIA core has no idea whether the
interrupt is requested, and, therefore, whether a call to disable_irq()
would be valid.  (We tried this around 2.4.17 / 2.5.1 kernel era, and
ended up throwing it out because of this problem.)

Therefore, it was decided back in around 2002 to disable the edge
triggering instead, resulting in all state transitions on the GPIO being
ignored.  That's what we actually need the hardware to do.

The commit above changes this behaviour; it explicitly prevents the 'no
trigger' state being selected.

The reason that request_irq() does not accept the 'no trigger' state is
for compatibility with existing drivers which do not provide their desired
triggering configuration.  The set_irq_type() function is 'new' and not
used by non-trigger aware drivers.

Therefore, revert this change, and restore previously working platforms
back to their former state.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: linux@arm.linux.org.uk
Cc: Ingo Molnar <mingo@elte.hu>
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-06 13:33:27 +01:00
Ingo Molnar
737f24bda7 Merge branch 'perf/urgent' into perf/core
Conflicts:
	tools/perf/builtin-record.c
	tools/perf/builtin-top.c
	tools/perf/perf.h
	tools/perf/util/top.h

Merge reason: resolve these cherry-picking conflicts.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-05 09:20:08 +01:00
Grant Likely
abd2363f6a irq_domain/mips: Allow irq_domain on MIPS
This patch makes IRQ_DOMAIN usable on MIPS.  It uses an ugly workaround
to preserve current behaviour so that MIPS has time to add irq_domain
registration to the irq controller drivers.  The workaround will be
removed in Linux v3.6

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
2012-02-24 09:47:23 -07:00
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
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
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
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
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
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
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
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
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
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
Ido Yariv
550acb1926 genirq: Fix race condition when stopping the irq thread
In irq_wait_for_interrupt(), the should_stop member is verified before
setting the task's state to TASK_INTERRUPTIBLE and calling schedule().
In case kthread_stop sets should_stop and wakes up the process after
should_stop is checked by the irq thread but before the task's state
is changed, the irq thread might never exit:

kthread_stop                    irq_wait_for_interrupt
------------                    ----------------------

                                 ...
...                              while (!kthread_should_stop()) {
kthread->should_stop = 1;
wake_up_process(k);
wait_for_completion(&kthread->exited);
...
                                     set_current_state(TASK_INTERRUPTIBLE);

                                     ...

                                     schedule();
                                 }

Fix this by checking if the thread should stop after modifying the
task's state.

[ tglx: Simplified it a bit ]

Signed-off-by: Ido Yariv <ido@wizery.com>
Link: http://lkml.kernel.org/r/1322740508-22640-1-git-send-email-ido@wizery.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
2011-12-02 11:54:24 +01:00
Linus Torvalds
ce8f55c2a0 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Don't allow per cpu interrupts to be suspended
2011-11-28 08:43:32 -08:00
Edward Donovan
52553ddffa genirq: fix regression in irqfixup, irqpoll
Commit fa27271bc8d2("genirq: Fixup poll handling") introduced a
regression that broke irqfixup/irqpoll for some hardware configurations.

Amidst reorganizing 'try_one_irq', that patch removed a test that
checked for 'action->handler' returning IRQ_HANDLED, before acting on
the interrupt.  Restoring this test back returns the functionality lost
since 2.6.39.  In the current set of tests, after 'action' is set, it
must precede '!action->next' to take effect.

With this and my previous patch to irq/spurious.c, c75d720fca, all
IRQ regressions that I have encountered are fixed.

Signed-off-by: Edward Donovan <edward.donovan@numble.net>
Reported-and-tested-by: Rogério Brito <rbrito@ime.usp.br>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org (2.6.39+)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-28 08:43:09 -08:00