From: Waiman Long Date: Mon, 11 May 2015 01:17:10 +0000 (-0400) Subject: locking/pvqspinlock: Replace xchg() by the more descriptive set_mb() X-Git-Tag: MMI-PSA29.97-13-9~9942^2~10 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=52c9d2badd1ae4d11c29de57d4e964e48afd3cb4;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git 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 Signed-off-by: Waiman Long Cc: Douglas Hatch Cc: Peter Zijlstra Cc: Scott J Norton Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h index b5758a95a8d3..27ab96dca68c 100644 --- a/kernel/locking/qspinlock_paravirt.h +++ b/kernel/locking/qspinlock_paravirt.h @@ -175,7 +175,7 @@ static void pv_wait_node(struct mcs_spinlock *node) * * Matches the xchg() from pv_kick_node(). */ - (void)xchg(&pn->state, vcpu_halted); + set_mb(pn->state, vcpu_halted); if (!READ_ONCE(node->locked)) pv_wait(&pn->state, vcpu_halted);