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a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763037269; bh=y1FfFIuMb0svp4ymlKmSDs7EFvaJvR5A3gJ3lpcq8Uk=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=EOp/uNGLEJX2/o1A0Oqqre+Il30QU6+REZ6YFDPWH0Meu5sP92HduOMkUe8kYKDAB VdMLglbLi+06rRrPRmZtPa85qJJEDgpngLeHOzUgN1sNS8CURZ8cVUCHj7//ChyqxF VuOuLY62yswpDC7bqM25vTrSPw6RUWv/LeQgStQLbLM2OrQuNcrt/3iInfvUmER6AV Nc+T6QelxZUkCLsxA1HPvQevv9ZkT7AKrzBRgRHmpmiBzB/hsqvjQmmfHqp2ZR80oO H3l+CR6hjebnQdqloBIy7TOa2FcbeyT4jGxT7OutE15lQOo+L85dtISsLNkHoQJUIp agdcL9uWkwFxQ== Message-ID: <13db54a4-5f02-4b57-8ff9-6298c2c4b8d3@kernel.org> Date: Thu, 13 Nov 2025 13:34:22 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 2/8] mm: Add PG_atomic To: Matthew Wilcox , Ojaswin Mujoo Cc: Christian Brauner , djwong@kernel.org, ritesh.list@gmail.com, john.g.garry@oracle.com, tytso@mit.edu, dchinner@redhat.com, hch@lst.de, linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, jack@suse.cz, nilay@linux.ibm.com, martin.petersen@oracle.com, rostedt@goodmis.org, axboe@kernel.dk, linux-block@vger.kernel.org, linux-trace-kernel@vger.kernel.org References: <5f0a7c62a3c787f2011ada10abe3826a94f99e17.1762945505.git.ojaswin@linux.ibm.com> From: "David Hildenbrand (Red Hat)" Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 5BFA2A000D X-Stat-Signature: rxeebikc6qzsbugxre9fgc3xu3ngwbn9 X-HE-Tag: 1763037270-539106 X-HE-Meta: U2FsdGVkX18sfVCfVEh636xnNBrnQj8KzQjECLVdoJx40BvKwFGeG3PujUymqw/KEkML5sm8jQvm37ynkvkqjeMniwj7AldnPK3OEzBC5meXlPxTnLbavGIhMbyPsu0pIbEyHUyn0LPKCwuGwwe+iPaKZaCC6JCJLPHN0UzlcAG/3n24F7y1ey4tWcdlR6Ea30MeTNxHCyPBintoCEAN++WIBU5Iaqxtnc29H18WrKZGI+y+GZNaeaPA7lDe1FZPrTw5kk5boQfdY3HfpFOpxp+/2qbb9muI6+6ypsPnuCSZRIiei8vRsQWaHby5l6jZXManvNuIX9Ym+5aZGW5DX/2fqGCsN7SUqfPcKH4E3A4L3rZ3sgWo0kR5c7OC377LW+S9nmebXrlk3C34r1w0rR7sZmiZ57aW7IsdjTtIi3Un5LlQtNzNua0z8kEq80Tstwn8HcKwzrX28km6EnjjLdMzIqhQAvZGs+5WyqolkYcD2e7hQUBdPAdxVpaYRiaj3oedld6XG3gX+roIR6kGuWWQ+RMy28+QUidXujMC1VZLE22XQjEkEpwGz5v9UWpD6QgCeVFfobVS/K6udXBF7m+mh9o5Ecow0COMhAvdSpST5HK47kYJok0Zir2vBkp/vxOOnr/noyyjDB9s/ZokIrWxer7lFfZGtmjInM6f3h9+ZIvdwQ2jZgmuVhCYwVfeFD+wAC7LvSCAU57hwoR01j27JOtIYn+5YPWt16OD18jh1funYowhTALDT6ogJkDawvDsFAD1osYWCZaRmJ/ZJyEzCl+W4NFPXK3bZPBCY8ULSYOILAas0gPnqsmN8XBtExqRXeaewt7TfBNeTabX7IUsHgGguieCXl8E+v+FLkEi+Pje897J+pPnb9SGQUdIr68b9B10M3Tk34JiH8ihlzV8P9WUqRiJrgrYbQUUSbBU5iwCTddv3n2n710kwBhwsA6ZR/YZbKn1pvpu+Gl pccT5G6U XqqZex5b24LVNgXqdArJDI+Px0Qfw7W9q5J1Dl/0x9AbiqgnO+vMvwf2FetPzhGvpL851eR6yZr35MnmC8W6dieSjKgMwNwVQD4g1T74bhkacLe+WPYvyBMlUqE+K06NYao4jJCP4LgG3DrbNR3XPzhl3kEAuYcK8A+EzVIdHL0oq0qq1yIi0xM9iZ4TEYvvGGQ5DTn1W/jPWLQasTAtSBHGO3WRjvIsMXkttdyFWqCgpkZs9hFGMEAQnE+4uHHgYVqCIcohjDoUVZfmWZ0c9W22lL+YIxL3Ipse+yIKz8q7Yacq1mRrHw+X+BTf1FIs3M1MSgRgNjsG0hFVS14Fu1Bl9cRPA5YvMCH/cEeOalHUtRyqTs+fkxt4fn9xDYoWKE/R7oWJwLvTiBpy8bqz8BDkiSQ== 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: On 12.11.25 16:56, Matthew Wilcox wrote: > On Wed, Nov 12, 2025 at 04:36:05PM +0530, Ojaswin Mujoo wrote: >> From: John Garry >> >> Add page flag PG_atomic, meaning that a folio needs to be written back >> atomically. This will be used by for handling RWF_ATOMIC buffered IO >> in upcoming patches. > > Page flags are a precious resource. I'm not thrilled about allocating one > to this rather niche usecase. Fully agreed. -- Cheers David