[PATCH V3 8/9] cpufreq: Keep policy->freq_table sorted in ascending order
Viresh Kumar
viresh.kumar at linaro.org
Tue Jun 7 14:28:07 AEST 2016
On 06-06-16, 23:56, Rafael J. Wysocki wrote:
> Since you are adding new code, you can write it so it doesn't do
> unnecessary checks from the start.
Hmm, I will do all that in this series only now.
> While at it, the "if ((freq < policy->min) || (freq > policy->max))"
> checks in cpufreq_find_index_l() and cpufreq_find_index_h() don't look
> good to me, because they very well may cause those function to return
> -EINVAL even when there's a valid table and that may cause
> acpi_cpufreq_fast_switch() to do bad things.
Hmm. So, the checks are for sure required here, otherwise we may end up
returning a frequency which we aren't allowed to. Also note that 'freq' here
isn't the target-freq, but the entry in the freq-table.
This routine should be returning a valid freq within the ranges specified by
policy->min/max.
Also note that these routines shall *never* return -EINVAL, otherwise it is
mostly a bug we are hitting.
We have enough checks in place to make sure that there is at least one valid
entry in the freq-table which is >= policy->min and <= policy->max.
I will take care of rest of the comments though. Thanks.
--
viresh
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