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[36.225.83.234]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2b988772ca0sm21162815ad.11.2026.04.29.04.29.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Apr 2026 04:29:34 -0700 (PDT) Date: Wed, 29 Apr 2026 19:29:30 +0800 From: Cheng-Yang Chou To: Tejun Heo Cc: Changwoo Min , void@manifault.com, arighi@nvidia.com, kernel-dev@igalia.com, sched-ext@lists.linux.dev, linux-kernel@vger.kernel.org, Ching-Chun Huang , Chia-Ping Tsai Subject: Re: [PATCH v3 0/3] sched_ext: Improve exit-time diagnostics Message-ID: <20260429192218.G59fd@cchengyang.duckdns.org> References: <20260429082318.420146-1-changwoo@igalia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hi Tejun, On Tue, Apr 28, 2026 at 10:57:27PM -1000, Tejun Heo wrote: > A few things I noticed that might be worth a follow-up: > > 1. scx_rcu_cpu_stall() takes no cpu, so the captured exit_cpu ends > up being the detector rather than the stalled one. We could > probably plumb it through from print_other_cpu_stall(), where > the stalled cpu is known. Do you mean we should change the function signatures to pass the stalled CPU through, e.g. panic_on_rcu_stall(int stalled_cpu) and scx_rcu_cpu_stall(int stalled_cpu)? > > 2. scx_hardlockup_irq_workfn() already has the hung cpu locally, so > passing it via __scx_exit() might be a bit more robust than > relying on irq_work routing. > > 3. Minor: "on cpu N" (kernel) vs "on CPU N" (UEI) - the casing > could probably match. > I have a draft patch and can send it out. If Changwoo or anyone else is already working on this, pls let me know! -- Cheers, Cheng-Yang