From a824a287f6eaec65f1cf7aedfd5f6b69d2d3858f Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 19 Apr 2018 09:40:32 -0700 Subject: [PATCH] rcu: Clear request other than RCU_GP_FLAG_INIT at GP end Once the grace period has ended, any RCU_GP_FLAG_FQS requests are irrelevant: The grace period has ended, so there is no longer any point in forcing quiescent states in order to try to make it end sooner. This commit therefore causes rcu_gp_cleanup() to clear any bits other than RCU_GP_FLAG_INIT from ->gp_flags at the end of the grace period. Signed-off-by: Paul E. McKenney Tested-by: Nicholas Piggin --- kernel/rcu/tree.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index c7b1e6b2a3da..25dbbc753fef 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2181,6 +2181,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) READ_ONCE(rsp->gpnum), TPS("newreq")); } + WRITE_ONCE(rsp->gp_flags, rsp->gp_flags & RCU_GP_FLAG_INIT); raw_spin_unlock_irq_rcu_node(rnp); }