Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'timers-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
"Two small fixes for the time(r) subsystem:
- Handle a subtle race between the clocksource watchdog and a
concurrent clocksource watchdog stop/start sequence correctly to
prevent a timer double add bug.
- Fix the file path for the core time namespace file"
* tag 'timers-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource: Prevent double add_timer_on() for watchdog_timer
MAINTAINERS: Correct path to time namespace source file
+10
-3
+1
-1
MAINTAINERS
+1
-1
MAINTAINERS
+9
-2
kernel/time/clocksource.c
+9
-2
kernel/time/clocksource.c
···
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next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
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if (next_cpu >= nr_cpu_ids)
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next_cpu = cpumask_first(cpu_online_mask);
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-
watchdog_timer.expires += WATCHDOG_INTERVAL;
297
-
add_timer_on(&watchdog_timer, next_cpu);
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+
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+
/*
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+
* Arm timer if not already pending: could race with concurrent
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+
* pair clocksource_stop_watchdog() clocksource_start_watchdog().
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+
*/
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+
if (!timer_pending(&watchdog_timer)) {
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+
watchdog_timer.expires += WATCHDOG_INTERVAL;
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+
add_timer_on(&watchdog_timer, next_cpu);
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+
}
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out:
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spin_unlock(&watchdog_lock);
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}