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b=koXv92vtg4amiUxo+E0FB6Q3wlqRd/moYmVlVgLGl7KJOBS0EykVY9kqZU7NFKqHr tRvIT9kMlNhDsdj3OMQC7HhyrjIpMSValH9x0h3dPWSV5xf34IRQX+SmlTTPwqtioR +06E3876eK5keDwI2Lb11i+IP1Ao24EDQ4CvjqsPG/u2Yx2NNakh9XU43tGQFmuXmI I5TTpYK8CKiWUTj1AwrzsGgpQkyRM+ExYcM9CxP/EKkZ3N467fynD2n/Gdo+efmAb+ IrPocPEyo7xpm5hS1PZH5l0WqWOBRIHz31+W7HoiceCqxmODyVutSVGM1eOS1uZZuY mhDLmhe3bfgBw== Message-ID: <9c10f799-907e-47ce-8ffb-e196ab0bee7e@kernel.org> Date: Tue, 3 Mar 2026 13:07:16 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 0/5] Introduce QPW for per-cpu operations (v2) Content-Language: en-US To: Marcelo Tosatti , linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Leonardo Bras , Thomas Gleixner , Waiman Long , Boqun Feun , Frederic Weisbecker References: <20260302154945.143996316@redhat.com> From: "Vlastimil Babka (SUSE)" In-Reply-To: <20260302154945.143996316@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: 74tddiz33jqg7anouiwxoz71i4i1jagi X-Rspamd-Queue-Id: 9765D40008 X-Rspamd-Server: rspam03 X-HE-Tag: 1772539642-457276 X-HE-Meta: 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 uwmpusKE mqmUmBgQGyt/OArmIW5GNaxt5X3w77r2HGR+oTTSE1bjXO2wHVf7fWx98xreIipNX5G0LxNj65wc1ggzK9N2M+Apwzo+YH8ev+s2zFkFR4NU+sZ05XV25WweW71HttU9iRblUP/CR/ct9wmULozdCantKEvPwaVoq+xBfUbXlkd+ETQlj8RJrA27NZJKsxi3uoY5xCMG3h3HvijEcoGg/bNiADTG+dTnH2rheePRkDkK5rcZaB6TmUtqyhCD2Hleh8JyfvSCnokzl1KcY6TbYxOtJyaTTek4JbAi/R6At3y6JeS0gz2WVqB8vjVbRKq3T4BvmMQ+XIWFIhqw= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/2/26 16:49, Marcelo Tosatti wrote: > Proposed solution: > A new interface called Queue PerCPU Work (QPW), which should replace > Work Queue in the above mentioned use case. > > If CONFIG_QPW=n this interfaces just wraps the current > local_locks + WorkQueue behavior, so no expected change in runtime. > > If CONFIG_QPW=y, and qpw kernel boot option =1, > queue_percpu_work_on(cpu,...) will lock that cpu's per-cpu structure > and perform work on it locally. This is possible because on > functions that can be used for performing remote work on remote > per-cpu structures, the local_lock (which is already > a this_cpu spinlock()), will be replaced by a qpw_spinlock(), which > is able to get the pe A process thing: several patches have Leo's S-o-b: but not From: You probably need his From: and your Co-developed-by: or some other variant, see Documentation/process/submitting-patches.rst section "When to use Acked-by:, Cc:, and Co-developed-by:"