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Date: Wed, 9 May 2018 00:01:13 -0700
From: Joel Fernandes <joel@joelfernandes.org>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>,
        Claudio Scordino <claudio@evidence.eu.com>,
        linux-kernel@vger.kernel.org,
        "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
        Patrick Bellasi <patrick.bellasi@arm.com>,
        Luca Abeni <luca.abeni@santannapisa.it>,
        Joel Fernandes <joelaf@google.com>, linux-pm@vger.kernel.org
Subject: Re: [RFC PATCH] sched/cpufreq/schedutil: handling urgent frequency
 requests
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On Wed, May 09, 2018 at 12:24:49PM +0530, Viresh Kumar wrote:
> On 09-05-18, 08:45, Juri Lelli wrote:
> > On 08/05/18 21:54, Joel Fernandes wrote:
> > Isn't this potentially introducing unneeded irq pressure (and doing the
> > whole wakeup the kthread thing), while the already active kthread could
> > simply handle multiple back-to-back requests before going to sleep?
> 
> And then we may need more instances of the work item and need to store
> a different value of next_freq with each work item, as we can't use
> the common one anymore as there would be races around accessing it ?

Exactly. I think it also doesn't make sense to over write an already
committed request either so better to store them separate (?). After the
"commit", that previous request is done..

- Joel