proc: less LOCK operations during lookup
Pseudo-code for lookup effectively is:
LOCK kernel
LOCK proc_subdir_lock
find PDE
UNLOCK proc_subdir_lock
get inode
LOCK proc_subdir_lock
goto unlock
UNLOCK proc_subdir_lock
UNLOCK kernel
We can get rid of LOCK/UNLOCK pair after getting inode simply by jumping
to unlock_kernel() directly.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 6a2fe51..75cd8d7 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -406,12 +406,12 @@
spin_unlock(&proc_subdir_lock);
error = -EINVAL;
inode = proc_get_inode(dir->i_sb, ino, de);
- spin_lock(&proc_subdir_lock);
- break;
+ goto out_unlock;
}
}
}
spin_unlock(&proc_subdir_lock);
+out_unlock:
unlock_kernel();
if (inode) {