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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Wed, Jun 30, 2021 at 01:51:51PM -0700, Suren Baghdasaryan wrote: > + /* cmpxchg should be called even when !force to set poll_scheduled */ > + if (atomic_cmpxchg(&group->poll_scheduled, 0, 1) && !force) > return; Why is that a cmpxchg() ? _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC445C11F64 for ; 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Thu, 1 Jul 2021 10:58:24 +0200 (CEST) Date: Thu, 1 Jul 2021 10:58:24 +0200 From: Peter Zijlstra To: Suren Baghdasaryan Cc: hannes@cmpxchg.org, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, matthias.bgg@gmail.com, minchan@google.com, timmurray@google.com, yt.chang@mediatek.com, wenju.xu@mediatek.com, jonathan.jmchen@mediatek.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, kernel-team@android.com, SH Chen Subject: Re: [PATCH v2 1/1] psi: stop relying on timer_pending for poll_work rescheduling Message-ID: References: <20210630205151.137001-1-surenb@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210630205151.137001-1-surenb@google.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jun 30, 2021 at 01:51:51PM -0700, Suren Baghdasaryan wrote: > + /* cmpxchg should be called even when !force to set poll_scheduled */ > + if (atomic_cmpxchg(&group->poll_scheduled, 0, 1) && !force) > return; Why is that a cmpxchg() ? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C13B9C11F64 for ; 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Thu, 1 Jul 2021 10:58:24 +0200 (CEST) Date: Thu, 1 Jul 2021 10:58:24 +0200 From: Peter Zijlstra To: Suren Baghdasaryan Cc: hannes@cmpxchg.org, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, matthias.bgg@gmail.com, minchan@google.com, timmurray@google.com, yt.chang@mediatek.com, wenju.xu@mediatek.com, jonathan.jmchen@mediatek.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, kernel-team@android.com, SH Chen Subject: Re: [PATCH v2 1/1] psi: stop relying on timer_pending for poll_work rescheduling Message-ID: References: <20210630205151.137001-1-surenb@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210630205151.137001-1-surenb@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 30, 2021 at 01:51:51PM -0700, Suren Baghdasaryan wrote: > + /* cmpxchg should be called even when !force to set poll_scheduled */ > + if (atomic_cmpxchg(&group->poll_scheduled, 0, 1) && !force) > return; Why is that a cmpxchg() ?