diff options
| author | Frederic Weisbecker <frederic@kernel.org> | 2024-01-29 15:56:36 -0800 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2024-02-06 10:56:35 +0100 |
| commit | dad6a09f3148257ac1773cd90934d721d68ab595 (patch) | |
| tree | 98f82d7b233d26ee5f7e9cfb790fb53c71abee42 /include | |
| parent | 54be6c6c5ae8e0d93a6c4641cb7528eb0b6ba478 (diff) | |
hrtimer: Report offline hrtimer enqueue
The hrtimers migration on CPU-down hotplug process has been moved
earlier, before the CPU actually goes to die. This leaves a small window
of opportunity to queue an hrtimer in a blind spot, leaving it ignored.
For example a practical case has been reported with RCU waking up a
SCHED_FIFO task right before the CPUHP_AP_IDLE_DEAD stage, queuing that
way a sched/rt timer to the local offline CPU.
Make sure such situations never go unnoticed and warn when that happens.
Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier")
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240129235646.3171983-4-boqun.feng@gmail.com
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/hrtimer.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 87e3bedf8eb0..641c4567cfa7 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -157,6 +157,7 @@ enum hrtimer_base_type { * @max_hang_time: Maximum time spent in hrtimer_interrupt * @softirq_expiry_lock: Lock which is taken while softirq based hrtimer are * expired + * @online: CPU is online from an hrtimers point of view * @timer_waiters: A hrtimer_cancel() invocation waits for the timer * callback to finish. * @expires_next: absolute time of the next event, is required for remote @@ -179,7 +180,8 @@ struct hrtimer_cpu_base { unsigned int hres_active : 1, in_hrtirq : 1, hang_detected : 1, - softirq_activated : 1; + softirq_activated : 1, + online : 1; #ifdef CONFIG_HIGH_RES_TIMERS unsigned int nr_events; unsigned short nr_retries; |