From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Wed, 11 Jul 2018 22:36:43 +0000 (-0700)
Subject: sched/membarrier: Replace synchronize_sched() with synchronize_rcu()
X-Git-Tag: v5.0-rc1~152^2^2~17^2~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=78d125d33858d00756baf0f40e75e77dcbfbea55;p=thirdparty%2Fkernel%2Flinux.git

sched/membarrier: Replace synchronize_sched() with synchronize_rcu()

Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, the synchronize_sched()
in sys_membarrier() can be replaced by synchronize_rcu().  This commit
therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c
index 76e0eaf4654e0..388a7a6c1aa2c 100644
--- a/kernel/sched/membarrier.c
+++ b/kernel/sched/membarrier.c
@@ -298,7 +298,7 @@ SYSCALL_DEFINE2(membarrier, int, cmd, int, flags)
 		if (tick_nohz_full_enabled())
 			return -EINVAL;
 		if (num_online_cpus() > 1)
-			synchronize_sched();
+			synchronize_rcu();
 		return 0;
 	case MEMBARRIER_CMD_GLOBAL_EXPEDITED:
 		return membarrier_global_expedited();