Re: [PATCH 04/10] cpufreq: ondemand: only queue canceled works from update_sampling_rate()

On 26-06-15, 12:20, Preeti U Murthy wrote:

On 06/22/2015 01:32 PM, Viresh Kumar wrote:

quoted

The sampling rate is updated with a call to update_sampling_rate(), and
we process CPUs one by one here. While the work is canceled on per-cpu
basis, it is getting enqueued (by mistake) for all policy->cpus.

That would result in wasting cpu cycles for queuing works which are
already queued and never canceled.

This patch is about queuing work only on the cpu for which it was
canceled earlier.

gov_queue_work() was missing the CPU parameter and it's better to club
'modify_all' and the new 'cpu' parameter to a 'cpus' mask. And so this
patch also changes the prototype of gov_queue_work() and fixes its
caller sites.

This looks good, except I did not understand the motivation to change
the 'modify_all' to 'load_eval'. Neither is saying the purpose better
than the other.

modify_all was used to check if we need to queue work on all CPUs or a
single cpu. But now we pass the cpumask and that name isn't valid
anymore. The only other thing we do with help of modify_all is
evaluating the load again and so is named load_eval.

I think the purpose is very much clear with load_eval now.

-- 
viresh