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Tue, 13 Feb 2024 09:52:52 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id k6pvAvQ7y2XxXwAAD6G6ig (envelope-from ); Tue, 13 Feb 2024 09:52:52 +0000 Date: Tue, 13 Feb 2024 10:52:47 +0100 From: Michal Hocko To: Vlastimil Babka Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Mel Gorman , Matthew Wilcox , Kent Overstreet , Pasha Tatashin , Mike Rapoport Subject: Re: [PATCH] mm: document memalloc_noreclaim_save() and memalloc_pin_save() Message-ID: References: <20240212182950.32730-2-vbabka@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240212182950.32730-2-vbabka@suse.cz> X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 1D2871C0006 X-Stat-Signature: jexsxm1bkn1dufge1toca43spbqu47zi X-HE-Tag: 1707817974-208813 X-HE-Meta: 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 TJ2jKSXT +3K5TdtEULNrEYI6OYp/Mecd5Bd+JpsFlEWaALLeQCv8CWQNx18W3Pd62Pmo1QDIhlEVtPociwZdBMegyskqQphJqmio7khnf7tfGOG6N8+NYIQCsM0cxgWNY8RgeECI6fcbA1d6ivqMidjbzW/Vteufo1l7m2Kn4+2/J5zIWdiGeFS977SlgFmFD8t/1L6g1G+rJM4k9tfqv+2EGLRBNNjcUJ7PCpM5qMOcAE9tN89CDkJ0KyADVU1Xn2IxFz8RZ+MNENIF47480uW2EJjyFeM2g+J4I5u1dL1aQzlDzIKQm1VeCNq7FolMNKjuyfxM+twKi/N8I/c9PJoeDI2JrlMlQ5x2o68DJw3qLUpZ6VlP9cFmTJ9cSXs40FGFRF22/B8l1s4GLg7iuA+M= 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 Mon 12-02-24 19:29:51, Vlastimil Babka wrote: > The memalloc_noreclaim_save() function currently has no documentation > comment, so the implications of its usage are not obvious. Namely that > it not only prevents entering reclaim (as the name suggests), but also > allows using all memory reserves and thus should be only used in > contexts that are allocating memory to free memory. This may lead to new > improper usages being added. > > Thus add a documenting comment, based on the description of > __GFP_MEMALLOC. While at it, also document memalloc_pin_save() so that > all the memalloc_ scopes are documented. In the comments describing the > relevant PF_MEMALLOC flags, refer to their scope setting functions. > > Signed-off-by: Vlastimil Babka Acked-by: Michal Hocko Thanks! -- Michal Hocko SUSE Labs