perf_counter: Allow for a wakeup watermark

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Currently we wake the mmap() consumer once every PAGE_SIZE of data
and/or once event wakeup_events when specified.

For high speed sampling this results in too many wakeups wrt. the
buffer size, hence change this.

We move the default wakeup limit to 1/4-th the buffer size, and
provide for means to manually specify this limit.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

...

This commit is contained in:

Peter Zijlstra 2009-09-17 19:01:10 +02:00 • committed by Ingo Molnar

parent 850bc73ffc

commit 2667de81f3

2 changed files with 27 additions and 15 deletions

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10

include/linux/perf_counter.h

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32

kernel/perf_counter.c

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