diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2012-11-12 22:07:34 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@rostedt.homelinux.com> | 2013-06-06 21:28:21 -0400 |
| commit | 667adbc7f858f74bd0ad14af6b547aabb0ef3818 (patch) | |
| tree | 45fbd469ce838ea42b84289abd9f8f6bacf9ce22 | |
| parent | 311da81219db3ed4698d43902c26a070dcb94ac9 (diff) | |
softirq: Fix nohz pending issue for real
We really need to iterate through all softirqs to find a potentially
blocked runner.
T1 runs softirq X (that cleared pending bit for X)
Interrupt raises softirq Y
T1 gets blocked on a lock and lock owner is not runnable
T1 schedules out
CPU goes idle and complains about pending softirq Y.
Now iterating over all softirqs lets us find the runner for X and
eliminate Y from the to warn about list as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | kernel/softirq.c | 13 |
1 files changed, 4 insertions, 9 deletions
diff --git a/kernel/softirq.c b/kernel/softirq.c index 7880b183e805..1d5b6638508b 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -100,20 +100,15 @@ void softirq_check_pending_idle(void) { static int rate_limit; struct softirq_runner *sr = &__get_cpu_var(softirq_runners); - u32 warnpending, pending = local_softirq_pending(); + u32 warnpending = local_softirq_pending(); + int i; if (rate_limit >= 10) return; - warnpending = pending; - - while (pending) { - struct task_struct *tsk; - int i = __ffs(pending); - - pending &= ~(1 << i); + for (i = 0; i < NR_SOFTIRQS; i++) { + struct task_struct *tsk = sr->runner[i]; - tsk = sr->runner[i]; /* * The wakeup code in rtmutex.c wakes up the task * _before_ it sets pi_blocked_on to NULL under |