From: Ingo Molnar This patch converts the superblock-lock semaphore to a mutex, affecting lock_super()/unlock_super(). Tested on ext3 and XFS. Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton --- fs/ext3/super.c | 2 +- fs/super.c | 2 +- include/linux/fs.h | 6 +++--- 3 files changed, 5 insertions(+), 5 deletions(-) diff -puN fs/ext3/super.c~mutex-subsystem-semaphore-to-mutex-vfs-sb-s_lock fs/ext3/super.c --- 25/fs/ext3/super.c~mutex-subsystem-semaphore-to-mutex-vfs-sb-s_lock Fri Jan 6 17:05:10 2006 +++ 25-akpm/fs/ext3/super.c Fri Jan 6 17:05:10 2006 @@ -2150,7 +2150,7 @@ int ext3_force_commit(struct super_block static void ext3_write_super (struct super_block * sb) { - if (down_trylock(&sb->s_lock) == 0) + if (mutex_trylock(&sb->s_lock) != 0) BUG(); sb->s_dirt = 0; } diff -puN fs/super.c~mutex-subsystem-semaphore-to-mutex-vfs-sb-s_lock fs/super.c --- 25/fs/super.c~mutex-subsystem-semaphore-to-mutex-vfs-sb-s_lock Fri Jan 6 17:05:10 2006 +++ 25-akpm/fs/super.c Fri Jan 6 17:05:10 2006 @@ -72,7 +72,7 @@ static struct super_block *alloc_super(v INIT_HLIST_HEAD(&s->s_anon); INIT_LIST_HEAD(&s->s_inodes); init_rwsem(&s->s_umount); - sema_init(&s->s_lock, 1); + mutex_init(&s->s_lock); down_write(&s->s_umount); s->s_count = S_BIAS; atomic_set(&s->s_active, 1); diff -puN include/linux/fs.h~mutex-subsystem-semaphore-to-mutex-vfs-sb-s_lock include/linux/fs.h --- 25/include/linux/fs.h~mutex-subsystem-semaphore-to-mutex-vfs-sb-s_lock Fri Jan 6 17:05:10 2006 +++ 25-akpm/include/linux/fs.h Fri Jan 6 17:05:10 2006 @@ -823,7 +823,7 @@ struct super_block { unsigned long s_magic; struct dentry *s_root; struct rw_semaphore s_umount; - struct semaphore s_lock; + struct mutex s_lock; int s_count; int s_syncing; int s_need_sync_fs; @@ -895,13 +895,13 @@ static inline int has_fs_excl(void) static inline void lock_super(struct super_block * sb) { get_fs_excl(); - down(&sb->s_lock); + mutex_lock(&sb->s_lock); } static inline void unlock_super(struct super_block * sb) { put_fs_excl(); - up(&sb->s_lock); + mutex_unlock(&sb->s_lock); } /* _