From cd23ac8ddb7be993f88bee893b89a8b4971c3651 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Thu, 24 May 2018 18:58:16 -0400 Subject: [PATCH] rcu: Add comment to the last sleep in the rcu tasks loop At the end of rcu_tasks_kthread() there's a lonely schedule_timeout_uninterruptible() call with no apparent rationale for its existence. But there is. It is to keep the thread from going into a tight loop if there's some anomaly. That really needs a comment. Link: http://lkml.kernel.org/r/20180524223839.GU3803@linux.vnet.ibm.com Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Paul E. McKenney --- kernel/rcu/update.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 4c7c49c106ee..39cb23d22109 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -814,6 +814,7 @@ static int __noreturn rcu_tasks_kthread(void *arg) list = next; cond_resched(); } + /* Paranoid sleep to keep this from entering a tight loop */ schedule_timeout_uninterruptible(HZ/10); } }