From a47d6b70e280401d553e7cac6f5750870de1ad21 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Thu, 26 May 2011 06:38:30 +0000 Subject: [PATCH] Btrfs: setup free ino caching in a more asynchronous way For a filesystem that has lots of files in it, the first time we mount it with free ino caching support, it can take quite a long time to setup the caching before we can create new files. Here we fill the cache with [highest_ino, BTRFS_LAST_FREE_OBJECTID] before we start the caching thread to search through the extent tree. Signed-off-by: Li Zefan Signed-off-by: Chris Mason --- fs/btrfs/inode-map.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-) diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c index 000970512624..3262cd17a12f 100644 --- a/fs/btrfs/inode-map.c +++ b/fs/btrfs/inode-map.c @@ -60,12 +60,12 @@ again: while (1) { smp_mb(); - if (fs_info->closing > 1) + if (fs_info->closing) goto out; leaf = path->nodes[0]; slot = path->slots[0]; - if (path->slots[0] >= btrfs_header_nritems(leaf)) { + if (slot >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) goto out; @@ -100,7 +100,7 @@ again: if (key.type != BTRFS_INODE_ITEM_KEY) goto next; - if (key.objectid >= BTRFS_LAST_FREE_OBJECTID) + if (key.objectid >= root->highest_objectid) break; if (last != (u64)-1 && last + 1 != key.objectid) { @@ -114,9 +114,9 @@ next: path->slots[0]++; } - if (last < BTRFS_LAST_FREE_OBJECTID - 1) { + if (last < root->highest_objectid - 1) { __btrfs_add_free_space(ctl, last + 1, - BTRFS_LAST_FREE_OBJECTID - last - 1); + root->highest_objectid - last - 1); } spin_lock(&root->cache_lock); @@ -136,8 +136,10 @@ out: static void start_caching(struct btrfs_root *root) { + struct btrfs_free_space_ctl *ctl = root->free_ino_ctl; struct task_struct *tsk; int ret; + u64 objectid; spin_lock(&root->cache_lock); if (root->cached != BTRFS_CACHE_NO) { @@ -156,6 +158,19 @@ static void start_caching(struct btrfs_root *root) return; } + /* + * It can be quite time-consuming to fill the cache by searching + * through the extent tree, and this can keep ino allocation path + * waiting. Therefore at start we quickly find out the highest + * inode number and we know we can use inode numbers which fall in + * [highest_ino + 1, BTRFS_LAST_FREE_OBJECTID]. + */ + ret = btrfs_find_free_objectid(root, &objectid); + if (!ret && objectid <= BTRFS_LAST_FREE_OBJECTID) { + __btrfs_add_free_space(ctl, objectid, + BTRFS_LAST_FREE_OBJECTID - objectid + 1); + } + tsk = kthread_run(caching_kthread, root, "btrfs-ino-cache-%llu\n", root->root_key.objectid); BUG_ON(IS_ERR(tsk)); @@ -209,7 +224,8 @@ again: start_caching(root); - if (objectid <= root->cache_progress) + if (objectid <= root->cache_progress || + objectid > root->highest_objectid) __btrfs_add_free_space(ctl, objectid, 1); else __btrfs_add_free_space(pinned, objectid, 1);