From: Frederic Weisbecker <frederic@xxxxxxxxxx> During a toggle operations, rcu_do_batch() may be invoked concurrently by softirqs and offloaded processing for a given CPU's callbacks. This commit therefore makes sure cond_resched() is invoked only from the offloaded context. Cc: Josh Triplett <josh@xxxxxxxxxxxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> Cc: Lai Jiangshan <jiangshanlai@xxxxxxxxx> Cc: Joel Fernandes <joel@xxxxxxxxxxxxxxxxx> Cc: Neeraj Upadhyay <neeraju@xxxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Inspired-by: Paul E. McKenney <paulmck@xxxxxxxxxx> Tested-by: Boqun Feng <boqun.feng@xxxxxxxxx> Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx> --- kernel/rcu/tree.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 83362f6..4ef59a5 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2516,8 +2516,7 @@ static void rcu_do_batch(struct rcu_data *rdp) /* Exceeded the time limit, so leave. */ break; } - if (offloaded) { - WARN_ON_ONCE(in_serving_softirq()); + if (!in_serving_softirq()) { local_bh_enable(); lockdep_assert_irqs_enabled(); cond_resched_tasks_rcu_qs(); -- 2.9.5