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b=MS4sJi78yYKjENIYjg+zN5FME+vxsGWJ09Ty6riuWJiKlzblTGFPuBT28uq/PQEcy vUxNYRIz4qNL7hNQ529tFhRhm3Qy20kGw9aM50kI9a8wBwtwcvCe+78zrHQbLyeldX vJQDAm/+4ji9DLR2O9LoJ5dePBatlrNDtJqMAcu5C5tXEliGO4ZD1ZpIXR39PXl3cP 0bAqppA5J61zVGmsCcXeB4L5aZSS/wGmubiKrxY3ZfjM6looctHd0v95paeb4x/mvR 01ALiaaxl/m9LCjARz1RFfFL/+bpxYaqE7eAJjFa4dGIOuXGgV043RiYf4JKdg4fcf 9PwOaKfl2nHmw== Date: Tue, 27 Jan 2026 14:51:30 +0100 From: Frederic Weisbecker To: Marco Crivellari Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Tejun Heo , Lai Jiangshan , Sebastian Andrzej Siewior , Michal Hocko , Andrew Morton Subject: Re: [PATCH v2 2/3] mm: Replace use of system_wq with system_percpu_wq Message-ID: References: <20260113114630.152942-1-marco.crivellari@suse.com> <20260113114630.152942-3-marco.crivellari@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260113114630.152942-3-marco.crivellari@suse.com> X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 400A840006 X-Stat-Signature: f7m847gjh4ujaewwab3ty9up8wo1o3e9 X-Rspam-User: X-HE-Tag: 1769521894-847091 X-HE-Meta: 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 FmQ5MgP9 /IBApg0P7Hp6BnQG5XhkZBER6wyA84ou1EtE9W/0ITs38eMeF+aD0TXBotvIXkPBtOnV40aPQK5ONv6DojICnPx7yMu6hb95F9a0imG3Jh0+XrURsDUM/NjCdobTuuE4kTRqbNtMPJqEd1j8OSzKFjlDcy38r65F1xR2q01b94GVapr8/kKfcjSF48Ce1NhrRiaiKM8WIVOppZQV/d3VMmy7NDabBFrdKlTC0v57djNufvKZ8wSXbqxCu3QGeETERQ2Db4sYRrTQuTkG8xNNQidM3wbkkAysZIINW1sRaUImJ07Of+oh3HCbrkoQceCF30vllsRCP6TzJ6qfp+ffMaAwO26GyUzZSz2S+SDxh/tKRGcE= 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 13, 2026 at 12:46:29PM +0100, Marco Crivellari a écrit : > This patch continues the effort to refactor workqueue APIs, which has begun > with the changes introducing new workqueues and a new alloc_workqueue flag: > > commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq") > commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag") > > The point of the refactoring is to eventually alter the default behavior of > workqueues to become unbound by default so that their workload placement is > optimized by the scheduler. > > Before that to happen, workqueue users must be converted to the better named > new workqueues with no intended behaviour changes: > > system_wq -> system_percpu_wq > system_unbound_wq -> system_dfl_wq > > This way the old obsolete workqueues (system_wq, system_unbound_wq) can be > removed in the future. > > Link: https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/ > Suggested-by: Tejun Heo > Signed-off-by: Marco Crivellari Reviewed-by: Frederic Weisbecker -- Frederic Weisbecker SUSE Labs