diff options
| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2018-10-17 13:23:55 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-04-20 09:15:05 +0200 |
| commit | 507f2f17e044b3efc6516ad0ae66fb244752c569 (patch) | |
| tree | d36895b8da62119616e39fe3d55a89e472b07b0a /kernel | |
| parent | 1d41cd12307f96ebefbd856cfe26719c23d8d8ec (diff) | |
kernel: hung_task.c: disable on suspend
[ Upstream commit a1c6ca3c6de763459a6e93b644ec6518c890ba1c ]
It is possible to observe hung_task complaints when system goes to
suspend-to-idle state:
# echo freeze > /sys/power/state
PM: Syncing filesystems ... done.
Freezing user space processes ... (elapsed 0.001 seconds) done.
OOM killer disabled.
Freezing remaining freezable tasks ... (elapsed 0.002 seconds) done.
sd 0:0:0:0: [sda] Synchronizing SCSI cache
INFO: task bash:1569 blocked for more than 120 seconds.
Not tainted 4.19.0-rc3_+ #687
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
bash D 0 1569 604 0x00000000
Call Trace:
? __schedule+0x1fe/0x7e0
schedule+0x28/0x80
suspend_devices_and_enter+0x4ac/0x750
pm_suspend+0x2c0/0x310
Register a PM notifier to disable the detector on suspend and re-enable
back on wakeup.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/hung_task.c | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/kernel/hung_task.c b/kernel/hung_task.c index f9aaf4994062..2e4869fa66c9 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -15,6 +15,7 @@ #include <linux/lockdep.h> #include <linux/export.h> #include <linux/sysctl.h> +#include <linux/suspend.h> #include <linux/utsname.h> #include <linux/sched/signal.h> #include <linux/sched/debug.h> @@ -232,6 +233,28 @@ void reset_hung_task_detector(void) } EXPORT_SYMBOL_GPL(reset_hung_task_detector); +static bool hung_detector_suspended; + +static int hungtask_pm_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + switch (action) { + case PM_SUSPEND_PREPARE: + case PM_HIBERNATION_PREPARE: + case PM_RESTORE_PREPARE: + hung_detector_suspended = true; + break; + case PM_POST_SUSPEND: + case PM_POST_HIBERNATION: + case PM_POST_RESTORE: + hung_detector_suspended = false; + break; + default: + break; + } + return NOTIFY_OK; +} + /* * kthread which checks for tasks stuck in D state */ @@ -246,7 +269,8 @@ static int watchdog(void *dummy) long t = hung_timeout_jiffies(hung_last_checked, timeout); if (t <= 0) { - if (!atomic_xchg(&reset_hung_task, 0)) + if (!atomic_xchg(&reset_hung_task, 0) && + !hung_detector_suspended) check_hung_uninterruptible_tasks(timeout); hung_last_checked = jiffies; continue; @@ -260,6 +284,10 @@ static int watchdog(void *dummy) static int __init hung_task_init(void) { atomic_notifier_chain_register(&panic_notifier_list, &panic_block); + + /* Disable hung task detector on suspend */ + pm_notifier(hungtask_pm_notify, 0); + watchdog_task = kthread_run(watchdog, NULL, "khungtaskd"); return 0; |