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| author | Peter Zijlstra <[email protected]> | 2007-07-19 08:49:00 +0000 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2007-07-19 17:04:49 +0000 |
| commit | 96645678cd726e87ce42a0664de71e047e32bca4 (patch) | |
| tree | 116f568a090414777b481e8e5d9db55f420e4335 /drivers/misc/ibmasm/ibmasmfs.c | |
| parent | lockdep: fixup sk_callback_lock annotation (diff) | |
| download | kernel-96645678cd726e87ce42a0664de71e047e32bca4.tar.gz kernel-96645678cd726e87ce42a0664de71e047e32bca4.zip | |
lockstat: measure lock bouncing
__acquire
|
lock _____
| \
| __contended
| |
| wait
| _______/
|/
|
__acquired
|
__release
|
unlock
We measure acquisition and contention bouncing.
This is done by recording a cpu stamp in each lock instance.
Contention bouncing requires the cpu stamp to be set on acquisition. Hence we
move __acquired into the generic path.
__acquired is then used to measure acquisition bouncing by comparing the
current cpu with the old stamp before replacing it.
__contended is used to measure contention bouncing (only useful for preemptable
locks)
[[email protected]: cleanups]
Signed-off-by: Peter Zijlstra <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Diffstat (limited to 'drivers/misc/ibmasm/ibmasmfs.c')
0 files changed, 0 insertions, 0 deletions