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b=MD1e38zvow7+Y1gKwI7+ZJ6snWq4hCJWP21MAyKssd+zbq2r3Jjlsz8+Pw8Avpxh5 ZV+OeT2dolwEZx5v9hHkRvFs30IXTwdWpfU2wTdXO9B47zxsZLR6uerz7Rt4A4pmt5 TVE+mjOxAL1lxuLnePfSa5NLzV/GgjOfGE6qGuTiJTgRuuag/dhOyr5NmNXFKZ/6LT LlTT293LF29/Y1df7/Azw/9J1Fdsl2MPgHtLplsEyBEpBxaWb4uEUpb/b5e8B2vMJ7 Los7QmMIBEuH8JKC8mcJNegumoygW1S/hBOxv6KLee8NjMos4KFbfoOmDBEc4Bkk4z 0FMDBArgHv9QA== Date: Tue, 27 Jan 2026 14:49:16 +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 1/3] mm: Replace use of system_unbound_wq with system_dfl_wq Message-ID: References: <20260113114630.152942-1-marco.crivellari@suse.com> <20260113114630.152942-2-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: <20260113114630.152942-2-marco.crivellari@suse.com> X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 74499C000D X-Stat-Signature: f63m8mk99xmk6ccbbxmgwbae8cuammp8 X-Rspam-User: X-HE-Tag: 1769521760-512007 X-HE-Meta: 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 oQhKrpmC s4a3serJxlNbiDGf+w1U6fIsw2bYYJxWpfgF0HFsjDTLpsdJ6IW4+o73oh5Kj33XF5NhJ6UWpsEJ/VISOddSfgHFE2G/gNFeCx9WfD2Y0Cv+uJf5bXLeA41CeDZbCZjn1sRPOrfZv1+uyY9NsfwudGv8JKZelChoyS3VEJ3qPVbcE9qMlLSAw3/3C+z4AdFFuJ6E4MdnPyjAqW5FHzGalXDVQF6QxlUuO8yfVchYlQjihtnYy5w8fphgvTXh11N0neJBb6jA8LYNmRuQuB1DeH8kprVdqPTb+apPRiNx7Eiaj72oZpIiu7NutpUCYr2fWlgNaVr24kHi9PLgIM+agMLXMnPl9hRC8xa3pY9/V2bHY82U= 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 12:46:28PM +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