Davidlohr Bueso 370b262c89 ipc/sem: avoid idr tree lookup for interrupted semop ...

We can avoid the idr tree lookup (albeit possibly avoiding
idr_find_fast()) when being awoken in EINTR, as the semid will not
change in this context while blocked.  Use the sma pointer directly and
take the sem_lock, then re-check for RMID races.  We continue to
re-check the queue.status with the lock held such that we can detect
situations where we where are dealing with a spurious wakeup but another
task that holds the sem_lock updated the queue.status while we were
spinning for it.  Once we take the lock it obviously won't change again.

Being the only caller, get rid of sem_obtain_lock() altogether.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Davidlohr Bueso <[email protected]>
Cc: Manfred Spraul <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

2016-12-14 16:04:08 -08:00

..

compat_mq.c

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compat.c

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ipc_sysctl.c

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Makefile

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mq_sysctl.c

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mqueue.c

sched/wake_q: Rename WAKE_Q to DEFINE_WAKE_Q

2016-11-21 10:29:01 +01:00

msg.c

ipc: msg, make msgrcv work with LONG_MIN

2016-12-14 16:04:08 -08:00

msgutil.c

ipc: account for kmem usage on mqueue and msg

2016-10-27 18:43:43 -07:00

namespace.c

Merge branch 'nsfs-ioctls' into HEAD

2016-09-22 20:00:36 -05:00

sem.c

ipc/sem: avoid idr tree lookup for interrupted semop

2016-12-14 16:04:08 -08:00

shm.c

ipc/shm.c: coding style fixes

2016-12-14 16:04:08 -08:00

syscall.c

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util.c

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util.h

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