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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: E8C9FA0012 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: nj1opdxxxiwyubutpxigycsg3c9jqbzf X-HE-Tag: 1727989139-352777 X-HE-Meta: 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 gdFfYogT 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.004928, 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 Wed, Oct 02, 2024 at 12:41:29AM -0700, Christoph Hellwig wrote: > > > This looks pretty ugly. What speaks against a version of > > > filemap_add_folio that doesn't charge the memcg? > > What I'd propose is something like the patch below, plus proper > documentation. I like this much better as well. > Note that this now does the uncharge on the unlocked folio in the > error case. From a quick look that should be fine, but someone who > actually knows the code needs to confirm that. That's fine. For the same reason the non-atomic __folio_clear_locked() is fine in that case. The folio just has to be exclusive.