24 Jul, 2014
3 commits
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The only user of the cycle_last validation is the x86 TSC. In order to
provide NMI safe accessor functions for clock monotonic and
monotonic_raw we need to do that in the core.We can't do the TSC specific
if (now < cycle_last)
now = cycle_last;for the other wrapping around clocksources, but TSC has
CLOCKSOURCE_MASK(64) which actually does not mask out anything so if
now is less than cycle_last the subtraction will give a negative
result. So we can check for that in clocksource_delta() and return 0
for that case.Implement and enable it for x86
Signed-off-by: Thomas Gleixner
Signed-off-by: John Stultz -
We want to move the TSC sanity check into core code to make NMI safe
accessors to clock monotonic[_raw] possible. For this we need to
sanity check the delta calculation. Create a helper function and
convert all sites to use it.[ Build fix from jstultz ]
Signed-off-by: Thomas Gleixner
Signed-off-by: John Stultz -
Convert the core timekeeping logic to use timespec64s. This moves the
2038 issues out of the core logic and into all of the accessor
functions.Future changes will need to push the timespec64s out to all
timekeeping users, but that can be done interface by interface.Signed-off-by: John Stultz
Signed-off-by: Thomas Gleixner
Signed-off-by: John Stultz
30 May, 2013
1 commit
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Below is a patch from android kernel that maintains a histogram of
suspend times. Please review and provide feedback.Statistices on the time spent in suspend are kept in
/sys/kernel/debug/sleep_time.Cc: Android Kernel Team
Cc: Colin Cross
Cc: Todd Poynor
Cc: San Mehat
Cc: Benoit Goby
Cc: John Stultz
Cc: Thomas Gleixner
Signed-off-by: Colin Cross
Signed-off-by: Todd Poynor
[zoran.markovic@linaro.org: Re-formatted suspend time table to better
fit expected values. Moved accounting of suspend time into timekeeping
core. Removed CONFIG_SUSPEND_TIME flag and made the feature conditional
on CONFIG_DEBUG_FS. Changed the file name to sleep_time to better fit
terminology in timekeeping core. Changed seq_printf to seq_puts. Tweaked
commit message]
Signed-off-by: Zoran Markovic
Signed-off-by: John Stultz
