Miao Xie
2013-Jan-22 10:52 UTC
[PATCH 5/5] Btrfs: don''t traverse the ordered operation list repeatedly
btrfs_run_ordered_operations() needn''t traverse the ordered operation list repeatedly, it is because the transaction commiter will invoke it again when there is no other writer in this transaction, it can ensure that no one can add new objects into the ordered operation list. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> --- fs/btrfs/ordered-data.c | 19 +++++-------------- 1 files changed, 5 insertions(+), 14 deletions(-) diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index f107312..5548176 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -558,14 +558,10 @@ int btrfs_run_ordered_operations(struct btrfs_root *root, int wait) mutex_lock(&root->fs_info->ordered_operations_mutex); spin_lock(&root->fs_info->ordered_extent_lock); -again: list_splice_init(&root->fs_info->ordered_operations, &splice); - while (!list_empty(&splice)) { - btrfs_inode = list_entry(splice.next, struct btrfs_inode, ordered_operations); - inode = &btrfs_inode->vfs_inode; list_del_init(&btrfs_inode->ordered_operations); @@ -574,22 +570,20 @@ again: * the inode may be getting freed (in sys_unlink path). */ inode = igrab(inode); - - if (!wait && inode) { - list_add_tail(&BTRFS_I(inode)->ordered_operations, - &root->fs_info->ordered_operations); - } - if (!inode) continue; + + if (!wait) + list_add_tail(&BTRFS_I(inode)->ordered_operations, + &root->fs_info->ordered_operations); spin_unlock(&root->fs_info->ordered_extent_lock); work = btrfs_alloc_delalloc_work(inode, wait, 1); if (!work) { + spin_lock(&root->fs_info->ordered_extent_lock); if (list_empty(&BTRFS_I(inode)->ordered_operations)) list_add_tail(&btrfs_inode->ordered_operations, &splice); - spin_lock(&root->fs_info->ordered_extent_lock); list_splice_tail(&splice, &root->fs_info->ordered_operations); spin_unlock(&root->fs_info->ordered_extent_lock); @@ -603,9 +597,6 @@ again: cond_resched(); spin_lock(&root->fs_info->ordered_extent_lock); } - if (wait && !list_empty(&root->fs_info->ordered_operations)) - goto again; - spin_unlock(&root->fs_info->ordered_extent_lock); out: list_for_each_entry_safe(work, next, &works, list) { -- 1.6.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html