Re: [PATCH v7 3/6] cpufreq: powernv: Remove cpu_to_chip_id() from hot-path

From: Viresh Kumar
Date: Thu Jan 28 2016 - 03:29:06 EST


On 28-01-16, 12:55, Shilpasri G Bhat wrote:
> cpu_to_chip_id() does a DT walk through to find out the chip id by
> taking a contended device tree lock. This adds an unnecessary overhead
> in a hot path. So instead of calling cpu_to_chip_id() everytime cache
> the chip ids for all cores in the array 'core_to_chip_map' and use it
> in the hotpath.
>
> Reported-by: Anton Blanchard <anton@xxxxxxxxx>
> Signed-off-by: Shilpasri G Bhat <shilpa.bhat@xxxxxxxxxxxxxxxxxx>
> ---
> Changes from v6:
> - Minor changes to move the code 'cpumask_copy()' after 'core_to_chip_map'
> is allocated.
> - Move 'kfree(chips)' to a separate patch.

See, you weren't that bad :)

Just that you missed saying that individual patches contain
version-log in cover-letter :)

Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

--
viresh