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Mon, 12 Oct 2026 06:33:03 -0700 (PDT) From: Kayra Cizmeci To: christian.loehle@arm.com Cc: bsegall@google.com, dietmar.eggemann@arm.com, juri.lelli@redhat.com, kayracizmeci@gmail.com, kprateek.nayak@amd.com, linux-kernel@vger.kernel.org, mgorman@suse.de, mingo@redhat.com, peterz@infradead.org, rostedt@goodmis.org, vincent.guittot@linaro.org, vschneid@redhat.com Subject: Re: [PATCH v3] sched/fair: remove dead code on enqueue_task_fair() Date: Mon, 12 Oct 2026 16:33:00 +0300 Message-ID: <20261012133300.2617-1-kayracizmeci@gmail.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > On 9/11/26 17:02, Kayra Cizmeci wrote: > > cfs_rq->curr == se path on enqueue_task_fair() seems to be unachievable. > Sashiko disagrees so I had a look and indeed cfs_rq unthrottling reaches this: > https://sashiko.dev/#/patchset/179033365207.2819794.11851486661940182495.tip-bot2%40tip-bot2 > See the splat below. > I'm afraid we need to revert > 819224e506bc ("sched/fair: Remove dead code on enqueue_task_fair()") > on tip/sched/core. Ah... Fuck. Yeah we need to. Thanks for catching this early. > I guess it's non-obvious enough to deserve a comment... Probably... Thanks, Kayra