Re: [PATCH 02/10] clocksource: Simplify logic around clocksource wrapping saftey margins

[Stephen Boyd]

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@xxxxxxxxxxxxxxxxx>
> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Richard Cochran <richardcochran@xxxxxxxxx>
> Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
> Cc: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
> ---

For sched_clock.c part

Acked-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>

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