From: Paul E. McKenney Date: Tue, 1 May 2018 22:05:45 +0000 (-0700) Subject: rcu: Replace smp_wmb() with smp_store_release() for stall check X-Git-Tag: v4.19-rc1~214^2^2~43 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=91f63ced7dc4e80acd13386204327d5de00a672d;p=linux.git rcu: Replace smp_wmb() with smp_store_release() for stall check This commit gets rid of the smp_wmb() in record_gp_stall_check_time() in favor of an smp_store_release(). Signed-off-by: Paul E. McKenney --- diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index a4277c1087d9..439228b79811 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1246,9 +1246,9 @@ static void record_gp_stall_check_time(struct rcu_state *rsp) unsigned long j1; rsp->gp_start = j; - smp_wmb(); /* Record start time before stall time. */ j1 = rcu_jiffies_till_stall_check(); - WRITE_ONCE(rsp->jiffies_stall, j + j1); + /* Record ->gp_start before ->jiffies_stall. */ + smp_store_release(&rsp->jiffies_stall, j + j1); /* ^^^ */ rsp->jiffies_resched = j + j1 / 2; rsp->n_force_qs_gpstart = READ_ONCE(rsp->n_force_qs); }