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(cst-prg-14-82.cust.vodafone.cz. [46.135.14.82]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-b72bf9bc874sm1606655466b.54.2025.11.12.02.44.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Nov 2025 02:44:41 -0800 (PST) From: Mateusz Guzik To: brauner@kernel.org, jlayton@kernel.org Cc: viro@zeniv.linux.org.uk, jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mateusz Guzik Subject: [PATCH v2 1/2] filelock: use a consume fence in locks_inode_context() Date: Wed, 12 Nov 2025 11:44:31 +0100 Message-ID: <20251112104432.1785404-1-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Matches the idiom of storing a pointer with a release fence and safely getting the content with a consume fence after. Eliminates an actual fence on some archs. Signed-off-by: Mateusz Guzik --- include/linux/filelock.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/include/linux/filelock.h b/include/linux/filelock.h index c2ce8ba05d06..37e1b33bd267 100644 --- a/include/linux/filelock.h +++ b/include/linux/filelock.h @@ -232,7 +232,10 @@ bool locks_owner_has_blockers(struct file_lock_context *flctx, static inline struct file_lock_context * locks_inode_context(const struct inode *inode) { - return smp_load_acquire(&inode->i_flctx); + /* + * Paired with the fence in locks_get_lock_context(). + */ + return READ_ONCE(inode->i_flctx); } #else /* !CONFIG_FILE_LOCKING */ -- 2.48.1