From 140e53f20b159722903f0c87358bcd809aa9767e Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 9 Apr 2019 10:08:18 -0700 Subject: [PATCH] rcutorture: Add cond_resched() to forward-progress free-up loop The rcu_torture_fwd_prog_cbfree() function frees callbacks used during rcutorture's call_rcu() forward-progress test, but does so in a tight loop. This could cause problems given a very long list of callbacks to be freed, and actual testing produces lists with as many as 25M callbacks. This commit therefore adds a cond_resched() to this loop. While in the area, this commit also rearranges the lock releases to look a bit more sane. Signed-off-by: Paul E. McKenney --- kernel/rcu/rcutorture.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index efaa5b3f4d3f..7906ba2d9dad 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1674,16 +1674,18 @@ static unsigned long rcu_torture_fwd_prog_cbfree(void) for (;;) { spin_lock_irqsave(&rcu_fwd_lock, flags); rfcp = rcu_fwd_cb_head; - if (!rfcp) + if (!rfcp) { + spin_unlock_irqrestore(&rcu_fwd_lock, flags); break; + } rcu_fwd_cb_head = rfcp->rfc_next; if (!rcu_fwd_cb_head) rcu_fwd_cb_tail = &rcu_fwd_cb_head; spin_unlock_irqrestore(&rcu_fwd_lock, flags); kfree(rfcp); freed++; + cond_resched(); } - spin_unlock_irqrestore(&rcu_fwd_lock, flags); return freed; }