The following commit has been merged into the irq/core branch of tip:
Commit-ID: 6b2c339df90788ce6aeecee78d6494f262929206
Gitweb: https://git.kernel.org/tip/6b2c339df90788ce6aeecee78d6494f262929206
Author: Dirk Behme <dirk.behme@xxxxxxxxxxxx>
AuthorDate: Wed, 17 Mar 2021 11:20:12 +01:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Wed, 17 Mar 2021 12:59:35 +01:00
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: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Dirk Behme <dirk.behme@xxxxxxxxxxxx>
Signed-off-by: Eugeniu Rosca <erosca@xxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210317102012.32399-1-erosca@xxxxxxxxxxxxxx
---
kernel/softirq.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 8b44ab9..8d56bbf 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -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 (t->use_callback)
- t->callback(t);
- else
- t->func(t->data);
+ if (tasklet_should_run(t)) {
+ if (t->use_callback)
+ t->callback(t);
+ else
+ t->func(t->data);
+ }
tasklet_unlock(t);
continue;
}
|