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McKenney" , Juergen Gross , Ajay Kaher , Alexey Makhalov , Russell King , Catalin Marinas , Will Deacon , Huacai Chen , WANG Xuerui , Paul Walmsley , Palmer Dabbelt , Albert Ou , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Peter Zijlstra , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , "Liang, Kan" , Boris Ostrovsky , Josh Poimboeuf , Pawan Gupta , Sean Christopherson , Paolo Bonzini , Andy Lutomirski , Arnd Bergmann , Jason Baron , Steven Rostedt , Ard Biesheuvel , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Juri Lelli , Clark Williams , Yair Podemsky , Tomas Glozar , Vincent Guittot , Dietmar Eggemann , Ben Segall , Mel Gorman , Kees Cook , Andrew Morton , Christoph Hellwig , Shuah Khan , Sami Tolvanen , Miguel Ojeda , Alice Ryhl , "Mike Rapoport (Microsoft)" , Samuel Holland , Rong Xu , Nicolas Saenz Julienne , Geert Uytterhoeven , Yosry Ahmed , "Kirill A. Shutemov" , "Masami Hiramatsu (Google)" , Jinghao Jia , Luis Chamberlain , Randy Dunlap , Tiezhu Yang Subject: Re: [PATCH v4 03/30] rcu: Add a small-width RCU watching counter debug option Message-ID: References: <20250114175143.81438-1-vschneid@redhat.com> <20250114175143.81438-4-vschneid@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250114175143.81438-4-vschneid@redhat.com> X-Rspamd-Queue-Id: 7298F14000A X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: fc696j8pg7sig4sbbwh7snhzyeakw6id X-HE-Tag: 1737467812-727893 X-HE-Meta: U2FsdGVkX1/57H7ygfsmlBdRUOm3GjMw18gQ34QX1QTdqqxQ6pLPFTaP6k/GsRyCCcKK2YyyqOz2SVkurncu/p7L4hflaum/EUeLc9bxG1sAtChDSKgWlrMZruz1Bjw5tXo7QJUpfEd/SD+kiV/3WsBOSUpPTqM3iskxqpBCQE/UcDhnElivnlYLjIESoiYFPjif8LKSifTwKz8Svg7bLlakiQghCdNfpkuQXJ5f2Cecxap+doItbvAtYfTQvdautUbcVUVKQsCxnyLTEtW8zsUzVbgbc9H7cx6mGEhD/SUvZ2BBIig1/DYSKG5pCPqPkkQGD8J+f/oVQ3UlwiecEz3RFfy1EQCrI7fwhXqgdhPdvC+cXwaP2GuKWbIZpWW8kAju39AKg5lTxQRl3fbVMHQwC6GsLbdwLY20dBdE9zElk4RntA8EQ4wS/IjfgKgPt7HXsz7rXTjWWfGQV+sNw4N9/FktNNwThWboW/QeBzYXfG3oagfH1RxwTctFXeE/89yV1cUjWvzo3tMR3exJ+zRceZzQXkk14bQA58qnj6Ds6QPNQ2y8gr5ulwfZ0cxMDxoTH8PuJu9BUj0cuNV2/r2whoOy/AFzs5XxVi3bMAKv3cfI9REWGsvVT+KJXg8J8e1O0yStFeyHQe/GRVs6zo8MRd3N1rFIRTOm2yNVVrQ6wSM55MAsRbiFb5x4tgF7N8DHYi4vJ1+4lD9obbU5Bgp3t2wq4vztYCPp6zJuU4HIoNCTYgQjdPSXyFARmZlWF0VkeuUOvHuWqaps90adEJ3coDyXXx/IayA6gTQe4QMJiDAdYgYx8IQeLUa8bskAukyjFTQTi7q2pIz0eF6/M694cbVgHdYzk/nN+arHy/tqAuvN0G7L49wDSnjRYsr1WqDEn1RJPz7TdT2SDimS/8eYamPKc4W0kbTD1WrDjkqGFRRj96GqDkqJjwmrB7MEgx39P6REQKhNva54PeL EpHnN2GR 9E9Bad+Sx6cAXvilsfTPuyqOd4wS/YuL0Jk6Y59n610G5EsH3/g96O2Anp9A9okJD0gpcoHPDK7BNV6DH/6DlfuB50qlPu7bwUVgIpfL31sP+FPcNrbhGIE2mV74mbHx1/LRIx0IilBYWvrMQWrXSF5tsj8FrE4e1qgjRv/I08wr0fBtT2nHMiBHxMTQBZDMxlPilolRdYwy4B0pRbNCXbPRS1Yfj9ZM2FEIXe1d/t/7DdUu6VOG5JARLoZQYI+OdHTwz9HXx50Odme0o8+CPvKDbH6faKdvd+flTnpL9CxUA/gdjrI6F20q7/g6tUXr0Je5KE5MMOikySoW4aPHd/udPaBknFypJmlzievHm8kYvBtw= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Le Tue, Jan 14, 2025 at 06:51:16PM +0100, Valentin Schneider a écrit : > A later commit will reduce the size of the RCU watching counter to free up > some bits for another purpose. Paul suggested adding a config option to > test the extreme case where the counter is reduced to its minimum usable > width for rcutorture to poke at, so do that. > > Make it only configurable under RCU_EXPERT. While at it, add a comment to > explain the layout of context_tracking->state. > > Link: http://lore.kernel.org/r/4c2cb573-168f-4806-b1d9-164e8276e66a@paulmck-laptop > Suggested-by: Paul E. McKenney > Signed-off-by: Valentin Schneider > Reviewed-by: Paul E. McKenney Reviewed-by: Frederic Weisbecker