btrfs: Introduce extent_io_tree::owner to distinguish different io_trees

Btrfs has the following different extent_io_trees used:

- fs_info::free_extents[2]
- btrfs_inode::io_tree - for both normal inodes and the btree inode
- btrfs_inode::io_failure_tree
- btrfs_transaction::dirty_pages
- btrfs_root::dirty_log_pages

If we want to trace changes in those trees, it will be pretty hard to
distinguish them.

Instead of using hard-to-read pointer address, this patch will introduce
a new member extent_io_tree::owner to track the owner.

This modification needs all the callers of extent_io_tree_init() to
accept a new parameter @owner.

This patch provides the basis for later trace events.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 8 insertions, 4 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 130796639f88..46b368d84aa3 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1211,7 +1211,8 @@ static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
 	root->log_transid_committed = -1;
 	root->last_log_commit = 0;
 	if (!dummy)
-		extent_io_tree_init(fs_info, &root->dirty_log_pages, NULL);
+		extent_io_tree_init(fs_info, &root->dirty_log_pages,
+				    IO_TREE_ROOT_DIRTY_LOG_PAGES, NULL);
 
 	memset(&root->root_key, 0, sizeof(root->root_key));
 	memset(&root->root_item, 0, sizeof(root->root_item));
@@ -2141,7 +2142,8 @@ static void btrfs_init_btree_inode(struct btrfs_fs_info *fs_info)
 	inode->i_mapping->a_ops = &btree_aops;
 
 	RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
-	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree, inode);
+	extent_io_tree_init(fs_info, &BTRFS_I(inode)->io_tree,
+			    IO_TREE_INODE_IO, inode);
 	BTRFS_I(inode)->io_tree.track_uptodate = false;
 	extent_map_tree_init(&BTRFS_I(inode)->extent_tree);
 
@@ -2751,8 +2753,10 @@ int open_ctree(struct super_block *sb,
 	fs_info->block_group_cache_tree = RB_ROOT;
 	fs_info->first_logical_byte = (u64)-1;
 
-	extent_io_tree_init(fs_info, &fs_info->freed_extents[0], NULL);
-	extent_io_tree_init(fs_info, &fs_info->freed_extents[1], NULL);
+	extent_io_tree_init(fs_info, &fs_info->freed_extents[0],
+			    IO_TREE_FS_INFO_FREED_EXTENTS0, NULL);
+	extent_io_tree_init(fs_info, &fs_info->freed_extents[1],
+			    IO_TREE_FS_INFO_FREED_EXTENTS1, NULL);
 	fs_info->pinned_extents = &fs_info->freed_extents[0];
 	set_bit(BTRFS_FS_BARRIER, &fs_info->flags);