locking/pvqspinlock: Replace xchg() by the more descriptive set_mb()
authorWaiman Long <Waiman.Long@hp.com>
Mon, 11 May 2015 01:17:10 +0000 (21:17 -0400)
committerIngo Molnar <mingo@kernel.org>
Mon, 11 May 2015 07:51:52 +0000 (09:51 +0200)
commit52c9d2badd1ae4d11c29de57d4e964e48afd3cb4
tree00edebb52a79aec06420e26520d788d0e0373cbc
parente95e6f176c61dd0e7bd9fdfb4956df1f9bfe99d4
locking/pvqspinlock: Replace xchg() by the more descriptive set_mb()

The xchg() function was used in pv_wait_node() to set a certain
value and provide a memory barrier which is what the set_mb()
function is for.  This patch replaces the xchg() call by
set_mb().

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kernel/locking/qspinlock_paravirt.h