From: Zqiang <qiang1.zhang@xxxxxxxxx> Recording the work creation stack trace for KASAN reports in call_rcu() is expensive, due to unwinding the stack, but also due to acquiring depot_lock inside stackdepot (which may be contended). Because calling kasan_record_aux_stack_noalloc() does not require interrupts to already be disabled, this may unnecessarily extend the time with interrupts disabled. Therefore, move calling kasan_record_aux_stack() before the section with interrupts disabled. Acked-by: Marco Elver <elver@xxxxxxxxxx> Signed-off-by: Zqiang <qiang1.zhang@xxxxxxxxx> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx> --- kernel/rcu/tree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index f1bb7ccc00847..ca8d7dd026eeb 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3060,8 +3060,8 @@ void call_rcu(struct rcu_head *head, rcu_callback_t func) } head->func = func; head->next = NULL; - local_irq_save(flags); kasan_record_aux_stack_noalloc(head); + local_irq_save(flags); rdp = this_cpu_ptr(&rcu_data); /* Add the callback to our list. */ -- 2.31.1.189.g2e36527f23
