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From: Mateusz Guzik <mjguzik@gmail.com>
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 <mjguzik@gmail.com>
Subject: [PATCH] fs: unconditionally use atime_needs_update() in pick_link()
Date: Tue,  8 Apr 2025 09:36:41 +0200	[thread overview]
Message-ID: <20250408073641.1799151-1-mjguzik@gmail.com> (raw)

Vast majority of the time the func returns false.

This avoids a branch to determine whether we are in RCU mode.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
---
 fs/namei.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 360a86ca1f02..ae2643ff14dc 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1905,13 +1905,13 @@ static const char *pick_link(struct nameidata *nd, struct path *link,
 			unlikely(link->mnt->mnt_flags & MNT_NOSYMFOLLOW))
 		return ERR_PTR(-ELOOP);
 
-	if (!(nd->flags & LOOKUP_RCU)) {
+	if (unlikely(atime_needs_update(&last->link, inode))) {
+		if (nd->flags & LOOKUP_RCU) {
+			if (!try_to_unlazy(nd))
+				return ERR_PTR(-ECHILD);
+		}
 		touch_atime(&last->link);
 		cond_resched();
-	} else if (atime_needs_update(&last->link, inode)) {
-		if (!try_to_unlazy(nd))
-			return ERR_PTR(-ECHILD);
-		touch_atime(&last->link);
 	}
 
 	error = security_inode_follow_link(link->dentry, inode,
-- 
2.43.0


             reply	other threads:[~2025-04-08  7:37 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-08  7:36 Mateusz Guzik [this message]
2025-04-08  9:09 ` [PATCH] fs: unconditionally use atime_needs_update() in pick_link() Christian Brauner
2025-04-08 12:07 ` Jan Kara

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