fs: dcache scale dentry refcount
Make d_count non-atomic and protect it with d_lock. This allows us to ensure a
0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when
we start protecting many other dentry members with d_lock.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
diff --git a/fs/locks.c b/fs/locks.c
index 8729347..08415b2 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1389,7 +1389,7 @@
if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
goto out;
if ((arg == F_WRLCK)
- && ((atomic_read(&dentry->d_count) > 1)
+ && ((dentry->d_count > 1)
|| (atomic_read(&inode->i_count) > 1)))
goto out;
}