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McKenney" Cc: rostedt@goodmis.org, pjaroszynski@nvidia.com, Andrew Morton , Catalin Marinas , puranjay@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, kernel-team@meta.com, dcostantino@meta.com Subject: Re: [PATCH] mm/kmemleak: report RCU-tasks quiescent states during the scan Message-ID: References: <20260720-kmemleak_rcu_task-v1-1-5b460ade777d@debian.org> <20260720153917.2e428e489cd0873ac6d4e6da@linux-foundation.org> <5b83b0a0-708a-458a-bdbd-41c6d4610349@paulmck-laptop> <39c90e82-f785-4b47-9571-dd4b1339d685@paulmck-laptop> <743bf971-b4aa-416b-b72b-88b538be727a@paulmck-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <743bf971-b4aa-416b-b72b-88b538be727a@paulmck-laptop> X-Debian-User: leitao X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 608072000F X-Stat-Signature: 938z8zewy4phuo3rhjawchdk7mqyjgkz X-Rspam-User: X-HE-Tag: 1785521287-897635 X-HE-Meta: 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 DP9ceVm/ rLEZFwTJpL4wxuI4fyWzsPnc5T+awdoooTvNgvNKVebKme7TIdRkvHwnEsUBAwlJpb5wwjdXghY6/++kkP+juCZFuyovfmab5EW+ny4hacSPSa4uDMGnobPHAI2as2uVDAJ5xmL/AIeqQ6ZdaH/CJXY2kRzGsgduJWOVXnkoccb/mab5C2I6qBmPGM9vodY97z9WZxnOrkgH6bpdStP7bf04A6yZyyIKpwy3UCTLUy80Bv22I5Dp9Czz4msVisLgdvSUS Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Jul 30, 2026 at 07:57:22AM -0700, Paul E. McKenney wrote: > > I suppose we want two things: > > > > 1) change cond_resched() with cond_resched_tasks_rcu_qs() > > 2) Avoiding holding the ftrace lock while calling > > synchronize_rcu_tasks()? It can take up to 10 minutes on a healthy > > system to be releasd, right? > > I do very much like both of those options. ;-) > > If #2 is impossible, would it make sense to have a mutex_lock_idle() or > similar in order to sanctify the lock synchronize_rcu_tasks() latencies? How would mutex_lock_idle() differ from a regular mutex_lock() when sanctifying synchronize_rcu_tasks() latencies?