Commit 6b2c339d authored by Dirk Behme's avatar Dirk Behme Committed by Ingo Molnar
Browse files

softirq: s/BUG/WARN_ONCE/ on tasklet SCHED state not set 



Replace BUG() with WARN_ONCE() on wrong tasklet state, in order to:

 - increase the verbosity / aid in debugging
 - avoid fatal/unrecoverable state

Suggested-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarDirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: default avatarEugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210317102012.32399-1-erosca@de.adit-jv.com
parent 5c982c58

kernel/softirq.c

+18 −7
Original line number Diff line number Diff line
@@ -531,6 +531,18 @@ void __tasklet_hi_schedule(struct tasklet_struct *t) 
}

EXPORT_SYMBOL(__tasklet_hi_schedule);



static bool tasklet_should_run(struct tasklet_struct *t)

{

	if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state))

		return true;



	WARN_ONCE(1, "tasklet SCHED state not set: %s %pS\n",

		  t->use_callback ? "callback" : "func",

		  t->use_callback ? (void *)t->callback : (void *)t->func);



	return false;

}



static void tasklet_action_common(struct softirq_action *a,

				  struct tasklet_head *tl_head,

				  unsigned int softirq_nr)
@@ -550,13 +562,12 @@ static void tasklet_action_common(struct softirq_action *a, 


		if (tasklet_trylock(t)) {

			if (!atomic_read(&t->count)) {

				if (!test_and_clear_bit(TASKLET_STATE_SCHED,

							&t->state))

					BUG();

				if (tasklet_should_run(t)) {

					if (t->use_callback)

						t->callback(t);

					else

						t->func(t->data);

				}

				tasklet_unlock(t);

				continue;

			}