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| author | Thomas Gleixner <tglx@linutronix.de> | 2013-04-25 20:31:44 +0000 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2013-05-16 11:09:14 +0200 |
| commit | ba919d1caa2e624eb8c6cae1f2ce0a253e697d45 (patch) | |
| tree | 3f1ca3d84720e41093cd6723ff4a92122ecfec2e | |
| parent | 5d33b883aed81c6fbcd09c6f7c3619eee850a7e2 (diff) | |
| download | linux-ba919d1caa2e624eb8c6cae1f2ce0a253e697d45.tar.gz linux-ba919d1caa2e624eb8c6cae1f2ce0a253e697d45.tar.bz2 linux-ba919d1caa2e624eb8c6cae1f2ce0a253e697d45.zip | |
clocksource: Let timekeeping_notify return success/error
timekeeping_notify() can fail due cs->enable() failure. Though the
caller does not notice and happily keeps the wrong clocksource as the
current one.
Let the caller know about failure, so the current clocksource will be
shown correctly in sysfs.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Link: http://lkml.kernel.org/r/20130425143435.696321912@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | include/linux/clocksource.h | 2 | ||||
| -rw-r--r-- | kernel/time/clocksource.c | 6 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 5 |
3 files changed, 7 insertions, 6 deletions
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 7279b94c01da..aa6ba44e75d5 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -321,7 +321,7 @@ static inline void __clocksource_updatefreq_khz(struct clocksource *cs, u32 khz) } -extern void timekeeping_notify(struct clocksource *clock); +extern int timekeeping_notify(struct clocksource *clock); extern cycle_t clocksource_mmio_readl_up(struct clocksource *); extern cycle_t clocksource_mmio_readl_down(struct clocksource *); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index dda5c7130d93..1923a340bd91 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -611,10 +611,10 @@ static void clocksource_select(void) best = cs; break; } - if (curr_clocksource != best) { - printk(KERN_INFO "Switching to clocksource %s\n", best->name); + + if (curr_clocksource != best && !timekeeping_notify(best)) { + pr_info("Switched to clocksource %s\n", best->name); curr_clocksource = best; - timekeeping_notify(curr_clocksource); } } diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 98cd470bbe49..da6e10c7a378 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -648,14 +648,15 @@ static int change_clocksource(void *data) * This function is called from clocksource.c after a new, better clock * source has been registered. The caller holds the clocksource_mutex. */ -void timekeeping_notify(struct clocksource *clock) +int timekeeping_notify(struct clocksource *clock) { struct timekeeper *tk = &timekeeper; if (tk->clock == clock) - return; + return 0; stop_machine(change_clocksource, clock, NULL); tick_clock_notify(); + return tk->clock == clock ? 0 : -1; } /** |