linux-kernel - [PATCH] fs: touch up predicts in putname()

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Message-ID: <20251029134952.658450-1-mjguzik@gmail.com>
Date: Wed, 29 Oct 2025 14:49:52 +0100
From: Mateusz Guzik <mjguzik@...il.com>
To: brauner@...nel.org
Cc: viro@...iv.linux.org.uk,
	jack@...e.cz,
	linux-kernel@...r.kernel.org,
	linux-fsdevel@...r.kernel.org,
	Mateusz Guzik <mjguzik@...il.com>
Subject: [PATCH] fs: touch up predicts in putname()

1. we already expect the refcount is 1.
2. path creation predicts name == iname

I verified this straightens out the asm, no functional changes.

Signed-off-by: Mateusz Guzik <mjguzik@...il.com>
---

random annoyance i noticed while profiling

 fs/namei.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index ba29ec7b67c5..4692f25e7cd9 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -282,7 +282,7 @@ void putname(struct filename *name)
 		return;
 
 	refcnt = atomic_read(&name->refcnt);
-	if (refcnt != 1) {
+	if (unlikely(refcnt != 1)) {
 		if (WARN_ON_ONCE(!refcnt))
 			return;
 
@@ -290,7 +290,7 @@ void putname(struct filename *name)
 			return;
 	}
 
-	if (name->name != name->iname) {
+	if (unlikely(name->name != name->iname)) {
 		__putname(name->name);
 		kfree(name);
 	} else
-- 
2.34.1