diff options
author | Magnus Damm <magnus.damm@gmail.com> | 2009-07-28 17:09:55 -0400 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2009-07-31 08:12:36 -0400 |
commit | c7121843685de2bf7f3afd3ae1d6a146010bf1fc (patch) | |
tree | f3a098159b8463386cd6d55b6272b6604bfbb9ce /include | |
parent | 4be3bd7849165e7efa6b0b35a23d6a3598d97465 (diff) |
clocksource: Save mult_orig in clocksource_disable()
To fix the common case where ->enable() does not set up
mult, make sure mult_orig is saved in mult on disable.
Also add comments to explain why we do this.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Cc: johnstul@us.ibm.com
Cc: lethal@linux-sh.org
Cc: akpm@linux-foundation.org
LKML-Reference: <20090618152432.10136.9932.sendpatchset@rx1.opensource.se>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/clocksource.h | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index c56457c8334e..1219be4fb42e 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h | |||
@@ -293,7 +293,12 @@ static inline int clocksource_enable(struct clocksource *cs) | |||
293 | if (cs->enable) | 293 | if (cs->enable) |
294 | ret = cs->enable(cs); | 294 | ret = cs->enable(cs); |
295 | 295 | ||
296 | /* save mult_orig on enable */ | 296 | /* |
297 | * The frequency may have changed while the clocksource | ||
298 | * was disabled. If so the code in ->enable() must update | ||
299 | * the mult value to reflect the new frequency. Make sure | ||
300 | * mult_orig follows this change. | ||
301 | */ | ||
297 | cs->mult_orig = cs->mult; | 302 | cs->mult_orig = cs->mult; |
298 | 303 | ||
299 | return ret; | 304 | return ret; |
@@ -309,6 +314,13 @@ static inline int clocksource_enable(struct clocksource *cs) | |||
309 | */ | 314 | */ |
310 | static inline void clocksource_disable(struct clocksource *cs) | 315 | static inline void clocksource_disable(struct clocksource *cs) |
311 | { | 316 | { |
317 | /* | ||
318 | * Save mult_orig in mult so clocksource_enable() can | ||
319 | * restore the value regardless if ->enable() updates | ||
320 | * the value of mult or not. | ||
321 | */ | ||
322 | cs->mult = cs->mult_orig; | ||
323 | |||
312 | if (cs->disable) | 324 | if (cs->disable) |
313 | cs->disable(cs); | 325 | cs->disable(cs); |
314 | } | 326 | } |