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| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2010-10-14 14:01:34 +0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-10-18 19:58:50 +0200 |
| commit | e360adbe29241a0194e10e20595360dd7b98a2b3 (patch) | |
| tree | ef5fa5f50a895096bfb25bc11b25949603158238 /init | |
| parent | 8e5fc1a7320baf6076391607515dceb61319b36a (diff) | |
| download | lwn-e360adbe29241a0194e10e20595360dd7b98a2b3.tar.gz lwn-e360adbe29241a0194e10e20595360dd7b98a2b3.zip | |
irq_work: Add generic hardirq context callbacks
Provide a mechanism that allows running code in IRQ context. It is
most useful for NMI code that needs to interact with the rest of the
system -- like wakeup a task to drain buffers.
Perf currently has such a mechanism, so extract that and provide it as
a generic feature, independent of perf so that others may also
benefit.
The IRQ context callback is generated through self-IPIs where
possible, or on architectures like powerpc the decrementer (the
built-in timer facility) is set to generate an interrupt immediately.
Architectures that don't have anything like this get to do with a
callback from the timer tick. These architectures can call
irq_work_run() at the tail of any IRQ handlers that might enqueue such
work (like the perf IRQ handler) to avoid undue latencies in
processing the work.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[ various fixes ]
Signed-off-by: Huang Ying <ying.huang@intel.com>
LKML-Reference: <1287036094.7768.291.camel@yhuang-dev>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'init')
| -rw-r--r-- | init/Kconfig | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/init/Kconfig b/init/Kconfig index 2de5b1cbadd9..1ef0b439908e 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -21,6 +21,13 @@ config CONSTRUCTORS depends on !UML default y +config HAVE_IRQ_WORK + bool + +config IRQ_WORK + bool + depends on HAVE_IRQ_WORK + menu "General setup" config EXPERIMENTAL @@ -987,6 +994,7 @@ config PERF_EVENTS default y if (PROFILING || PERF_COUNTERS) depends on HAVE_PERF_EVENTS select ANON_INODES + select IRQ_WORK help Enable kernel support for various performance events provided by software and hardware. |