fs: annotate cdev_lock with __cacheline_aligned_in_smp

No need for the crapper to be susceptible to false-sharing.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20251203095508.291073-1-mjguzik@gmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/char_dev.c b/fs/char_dev.c
index c2ddb998f3c94361c8af419684e593f4b295b8b1..84a5a0699373cdf6312cf04c96b2a3d66c72fee8 100644 (file)
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -343,7 +343,7 @@ void __unregister_chrdev(unsigned int major, unsigned int baseminor,
        kfree(cd);
 }
 
-static DEFINE_SPINLOCK(cdev_lock);
+static __cacheline_aligned_in_smp DEFINE_SPINLOCK(cdev_lock);
 
 static struct kobject *cdev_get(struct cdev *p)
 {