Messages in this thread | | | Date | Fri, 09 Jan 2015 18:03:34 -0800 | From | Stephen Boyd <> | Subject | Re: [PATCH 02/10] clocksource: Simplify logic around clocksource wrapping saftey margins |
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On 01/09/2015 04:34 PM, John Stultz wrote: > The clocksource logic has a number of places where we try to > include a safety margin. Most of these are 12% safety margins, > but they are inconsistently applied and sometimes are applied > on top of each other. > > Additionally, in the previous patch, we corrected an issue > where we unintentionally in effect created a 50% saftey margin, > which these 12.5% margins where then added to. > > So to siplify the logic here, this patch removes the various > 12.5% margins, and consolidates adding the margin in one place: > clocks_calc_max_nsecs(). > > Addtionally, Linus prefers a 50% safety margin, as it allows > bad clock values to be more easily caught. This should really > have no net effect, due to the corrected issue earlier which > caused greater then 50% margins to be used w/o issue. > > Cc: Dave Jones <davej@codemonkey.org.uk> > Cc: Linus Torvalds <torvalds@linux-foundation.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Richard Cochran <richardcochran@gmail.com> > Cc: Prarit Bhargava <prarit@redhat.com> > Cc: Stephen Boyd <sboyd@codeaurora.org> > Cc: Ingo Molnar <mingo@kernel.org> > Cc: Peter Zijlstra <peterz@infradead.org> > Signed-off-by: John Stultz <john.stultz@linaro.org> > ---
For sched_clock.c part
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
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