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Wysocki" , Peter Zijlstra , Ingo Molnar , Patrick Bellasi , Juri Lelli , Luca Abeni , Todd Kjos , claudio@evidence.eu.com, kernel-team@android.com, linux-pm@vger.kernel.org Subject: Re: [PATCH RFC] schedutil: Address the r/w ordering race in kthread Message-ID: <20180523001808.GC55359@joelaf.mtv.corp.google.com> References: <20180522235028.80564-1-joel@joelfernandes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180522235028.80564-1-joel@joelfernandes.org> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 22, 2018 at 04:50:28PM -0700, Joel Fernandes (Google) wrote: > Currently there is a race in schedutil code for slow-switch single-CPU > systems. Fix it by enforcing ordering the write to work_in_progress to > happen before the read of next_freq. Aargh, s/before/after/. Commit log has above issue but code is Ok. Should I resend this patch or are there any additional comments? thanks! - Joel [..]