diff options
| author |   Thomas Gleixner <tglx@linutronix.de> | 2011-06-16 16:22:08 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2011-06-16 19:30:53 +0200 |
| commit | b5199515c25cca622495eb9c6a8a1d275e775088 (patch) | |
| tree | 250fc4f3d02c58eddf770e9d040edeafd0012e76 /include/linux/clocksource.h | |
| parent | timerfd: Fix wakeup of processes when timer is cancelled on clock change (diff) | |
| download | linux-dev-b5199515c25cca622495eb9c6a8a1d275e775088.tar.xz linux-dev-b5199515c25cca622495eb9c6a8a1d275e775088.zip | |
clocksource: Make watchdog robust vs. interruption
The clocksource watchdog code is interruptible and it has been
observed that this can trigger false positives which disable the TSC.
The reason is that an interrupt storm or a long running interrupt
handler between the read of the watchdog source and the read of the
TSC brings the two far enough apart that the delta is larger than the
unstable treshold. Move both reads into a short interrupt disabled
region to avoid that.
Reported-and-tested-by: Vernon Mauery <vernux@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
Diffstat (limited to 'include/linux/clocksource.h')
| -rw-r--r-- | include/linux/clocksource.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index d4646b48dc4a..18a1baf31f2d 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -188,6 +188,7 @@ struct clocksource { #ifdef CONFIG_CLOCKSOURCE_WATCHDOG /* Watchdog related data, used by the framework */ struct list_head wd_list; + cycle_t cs_last; cycle_t wd_last; #endif } ____cacheline_aligned; |