diff options
| author | Waiman Long <Waiman.Long@hp.com> | 2014-01-21 15:35:53 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2014-01-28 13:13:26 +0100 |
| commit | aff7385b5a16bca6b8d9243f01a9ea5a5b411e1d (patch) | |
| tree | ca8b03e4e6aa1d0fcd8ae971e98b0719fdb08666 /kernel/locking/mutex-debug.c | |
| parent | 270750dbc18a71b23d660df110e433ff9616a2d4 (diff) | |
locking/mutexes/mcs: Correct barrier usage
This patch corrects the way memory barriers are used in the MCS lock
with smp_load_acquire and smp_store_release fucnctions. The previous
barriers could leak critical sections if mcs lock is used by itself.
It is not a problem when mcs lock is embedded in mutex but will be an
issue when the mcs_lock is used elsewhere.
The patch removes the incorrect barriers and put in correct
barriers with the pair of functions smp_load_acquire and smp_store_release.
Suggested-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Jason Low <jason.low2@hp.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1390347353.3138.62.camel@schen9-DESK
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/locking/mutex-debug.c')
0 files changed, 0 insertions, 0 deletions