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charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 423A12001A X-Rspam-User: X-Stat-Signature: c7m4xwdyj5xteuwg4n3mz1mdrkoc3epa X-Rspamd-Server: rspam01 X-HE-Tag: 1710964001-880251 X-HE-Meta: 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 /KsA0MqQ 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.003778, 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, Mar 20, 2024 at 12:41:48PM -0700, Chris Li wrote: > On Wed, Mar 20, 2024 at 12:34=E2=80=AFPM Yosry Ahmed wrote: > > > you can expect it to be coherent. > > > > Fair enough, but don't we still need a barrier there? Couldn't some > > initializations still be reorder after zswap_lru_add()? >=20 > I am under the impression that the lru list handling function already > handles the barrier. If an explicit barrier is needed, wouldn't all > other lru callers have barriers sprinkling all over the place? list_lru_add() holds a lock, which implies a compiler barrier. I was wondering if we need smp_wmb() to prevent other CPUs from observing a partially initialized entry during writeback. I am not sure if the list lru makes such assumptions about the need for barriers.