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Wed, 08 Oct 2025 08:46:01 -0700 (PDT) MIME-Version: 1.0 References: <20251003203851.43128-1-sj@kernel.org> <20251003203851.43128-2-sj@kernel.org> In-Reply-To: <20251003203851.43128-2-sj@kernel.org> From: Nhat Pham Date: Wed, 8 Oct 2025 08:45:51 -0700 X-Gm-Features: AS18NWD8AQK_m0J9OQQ2568NHQvCpLirccXoMfHk6y_3-THO678-BMip4zWDvSk Message-ID: Subject: Re: [PATCH 1/4] mm/zswap: remove unnecessary dlen writes for incompressible pages To: SeongJae Park Cc: Andrew Morton , Chengming Zhou , Johannes Weiner , Yosry Ahmed , kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 4CA761A0010 X-Rspamd-Server: rspam11 X-Rspam-User: X-Stat-Signature: j986ja7954kn779sj6spn3ky13i5kxya X-HE-Tag: 1759938363-941236 X-HE-Meta: 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 1JOoLymg 3+nVHGjyRGqgit15cSfPln1lfPoMWkR8nnSdwvJOTB1gcqCqpeeMWsbLqFa5H2yaSGjEkZ61IEMQVcIn7lvNHw9MhLoZw2BiD/rbi2LvFV3T1pzVwwsrYstnhGZZy3CjdvHljJ7w5EBZ5GWAIl/sns9E6WLa6cV4aRR+6+t2VMIp6UPcI2HmtYTh+YkeRsJhRhFiKjXdK/r7nfoymE48CnxhVIcTYyCFYPQ//b8Gp0zA44BhaSKSBncpuD0JjrT3qNetMqrOT5DB7NTm0OjG61Zi16TG6H/x7NAxdk6sUfQdK62CSWcijY/oQsl+5v9CHUOdHfHic6NRbkVjX5kC0ME23bRfFU0Ay0OcOXGJGT7VlcMCgfrrr7cPscPsffJCqEha6zSShNXobIS22j3nFHkQekg== 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 Fri, Oct 3, 2025 at 1:38=E2=80=AFPM SeongJae Park wrote: > > Incompressible pages handling logic in zswap_compress() is setting > 'dlen' as PAGE_SIZE twice. Once before deciding whether to save the > content as is, and once again after it is decided to save it as is. > But the value of 'dlen' is used only if it is decided to save the > content as is, so the first write is unnecessary. It is not causing > real user issues, but making code confusing to read. Remove the > unnecessary write operation. > > Signed-off-by: SeongJae Park Acked-by: Nhat Pham