fs: mark lookup_slow() as noinline

Otherwise it gets inlined notably in walk_component(), which convinces
the compiler to push/pop additional registers in the fast path to
accomodate existence of the inlined version.

Shortens the fast path of that routine from 87 to 71 bytes.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20251119144930.2911698-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/namei.c b/fs/namei.c
index 5fbb05fb96b7529542a6bebf2268294536de250e..efa592a9815563e654eb307430e4214308446ab4 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1863,7 +1863,7 @@ again:
        return dentry;
 }
 
-static struct dentry *lookup_slow(const struct qstr *name,
+static noinline struct dentry *lookup_slow(const struct qstr *name,
                                  struct dentry *dir,
                                  unsigned int flags)
 {