inode: convert inode_sb_list_lock to per-sb
The process of reducing contention on per-superblock inode lists
starts with moving the locking to match the per-superblock inode
list. This takes the global lock out of the picture and reduces the
contention problems to within a single filesystem. This doesn't get
rid of contention as the locks still have global CPU scope, but it
does isolate operations on different superblocks form each other.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Dave Chinner <dchinner@redhat.com>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 1982437..33b813e 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1769,7 +1769,7 @@
{
struct inode *inode, *old_inode = NULL;
- spin_lock(&inode_sb_list_lock);
+ spin_lock(&blockdev_superblock->s_inode_list_lock);
list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) {
struct address_space *mapping = inode->i_mapping;
@@ -1781,13 +1781,13 @@
}
__iget(inode);
spin_unlock(&inode->i_lock);
- spin_unlock(&inode_sb_list_lock);
+ spin_unlock(&blockdev_superblock->s_inode_list_lock);
/*
* We hold a reference to 'inode' so it couldn't have been
* removed from s_inodes list while we dropped the
- * inode_sb_list_lock. We cannot iput the inode now as we can
+ * s_inode_list_lock We cannot iput the inode now as we can
* be holding the last reference and we cannot iput it under
- * inode_sb_list_lock. So we keep the reference and iput it
+ * s_inode_list_lock. So we keep the reference and iput it
* later.
*/
iput(old_inode);
@@ -1795,8 +1795,8 @@
func(I_BDEV(inode), arg);
- spin_lock(&inode_sb_list_lock);
+ spin_lock(&blockdev_superblock->s_inode_list_lock);
}
- spin_unlock(&inode_sb_list_lock);
+ spin_unlock(&blockdev_superblock->s_inode_list_lock);
iput(old_inode);
}