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(cst-prg-14-82.cust.vodafone.cz. [46.135.14.82]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-b76f59e8612sm142586066b.52.2025.11.27.04.24.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 Nov 2025 04:24:16 -0800 (PST) From: Mateusz Guzik To: brauner@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] dcache: predict the name matches if parent and length also match Date: Thu, 27 Nov 2025 13:24:12 +0100 Message-ID: <20251127122412.4131818-1-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: quoted-printable Content-Type: text/plain; charset="utf-8" dentry_cmp() has predicts inside, but they were not enough to convince the compiler. As for difference in asm, some of the code is reshuffled and there is one less unconditional jump to get there. Signed-off-by: Mateusz Guzik Reviewed-by: Jan Kara --- i know it's late, but given the non-semantic-modifying nature of the change, i think it can still make it for 6.19 fs/dcache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/dcache.c b/fs/dcache.c index 23d1752c29e6..bc84f89156fa 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2346,7 +2346,7 @@ struct dentry *__d_lookup_rcu(const struct dentry *pa= rent, continue; if (dentry->d_name.hash_len !=3D hashlen) continue; - if (dentry_cmp(dentry, str, hashlen_len(hashlen)) !=3D 0) + if (unlikely(dentry_cmp(dentry, str, hashlen_len(hashlen)) !=3D 0)) continue; *seqp =3D seq; return dentry; --=20 2.34.1