linux-stable/kernel/locking
Will Deacon 77e430e3e4 locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
The qrwlock implementation is slightly heavy in its use of memory
barriers, mainly through the use of _cmpxchg() and _return() atomics, which
imply full barrier semantics.

This patch modifies the qrwlock code to use the more relaxed atomic
routines so that we can reduce the unnecessary barrier overhead on
weakly-ordered architectures.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-7-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-12 11:59:06 +02:00
..
lglock.c sched/stop_machine: Fix deadlock between multiple stop_two_cpus() 2015-06-19 10:03:12 +02:00
lockdep.c Merge branch 'sched-hrtimers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-06-24 15:09:40 -07:00
lockdep_internals.h lockdep: Increase static allocations 2014-04-18 14:20:50 +02:00
lockdep_proc.c lockdep: Fix a race between /proc/lock_stat and module unload 2015-06-07 15:46:30 +02:00
lockdep_states.h
locktorture.c locktorture: Change longdelay_us to longdelay_ms 2015-05-27 12:59:57 -07:00
Makefile rtmutex: Delete scriptable tester 2015-07-20 11:45:45 +02:00
mcs_spinlock.h locking/qspinlock: Introduce a simple generic 4-byte queued spinlock 2015-05-08 12:36:25 +02:00
mutex-debug.c mutex: Always clear owner field upon mutex_unlock() 2015-01-09 11:20:39 +01:00
mutex-debug.h
mutex.c locking/mutex: Further simplify mutex_spin_on_owner() 2015-04-09 08:10:23 +02:00
mutex.h locking/mutexes: Use MUTEX_SPIN_ON_OWNER when appropriate 2014-08-13 10:32:02 +02:00
osq_lock.c locking: Remove ACCESS_ONCE() usage 2015-02-24 08:44:16 +01:00
percpu-rwsem.c locking: Move the percpu-rwsem code to kernel/locking/ 2013-11-06 09:24:22 +01:00
qrwlock.c locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics 2015-08-12 11:59:06 +02:00
qspinlock.c locking/pvqspinlock: Only kick CPU at unlock time 2015-08-03 10:57:11 +02:00
qspinlock_paravirt.h locking/pvqspinlock: Only kick CPU at unlock time 2015-08-03 10:57:11 +02:00
rtmutex-debug.c rtmutex: Cleanup deadlock detector debug logic 2014-06-21 22:05:30 +02:00
rtmutex-debug.h rtmutex: Cleanup deadlock detector debug logic 2014-06-21 22:05:30 +02:00
rtmutex.c rtmutex: Delete scriptable tester 2015-07-20 11:45:45 +02:00
rtmutex.h rtmutex: Cleanup deadlock detector debug logic 2014-06-21 22:05:30 +02:00
rtmutex_common.h rtmutex: Delete scriptable tester 2015-07-20 11:45:45 +02:00
rwsem-spinlock.c locking/rwsem: Document barrier need when waking tasks 2015-02-18 16:57:10 +01:00
rwsem-xadd.c locking/rwsem: Reduce spinlock contention in wakeup after up_read()/up_write() 2015-05-08 12:27:59 +02:00
rwsem.c locking/rwsem: Set lock ownership ASAP 2015-02-18 16:57:13 +01:00
rwsem.h locking/rwsem: Set lock ownership ASAP 2015-02-18 16:57:13 +01:00
semaphore.c locking/semaphore: Resolve some shadow warnings 2014-09-04 07:17:24 +02:00
spinlock.c spinlock: Add spin_lock_bh_nested() 2015-01-03 14:32:57 -05:00
spinlock_debug.c locking: Move the spinlock code to kernel/locking/ 2013-11-06 07:55:21 +01:00