From 7f913c7cfec62b91ceb4383c4dfb481092ae9d20 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Mon, 17 Feb 2020 14:16:53 +0800 Subject: btrfs: relocation: Check cancel request after each data page read When relocating a data extents with large large data extents, we spend most of our time in relocate_file_extent_cluster() at stage "moving data extents": 1) | btrfs_relocate_block_group [btrfs]() { 1) | relocate_file_extent_cluster [btrfs]() { 1) $ 6586769 us | } 1) + 18.260 us | relocate_file_extent_cluster [btrfs](); 1) + 15.770 us | relocate_file_extent_cluster [btrfs](); 1) $ 8916340 us | } 1) | btrfs_relocate_block_group [btrfs]() { 1) | relocate_file_extent_cluster [btrfs]() { 1) $ 11611586 us | } 1) + 16.930 us | relocate_file_extent_cluster [btrfs](); 1) + 15.870 us | relocate_file_extent_cluster [btrfs](); 1) $ 14986130 us | } To make data relocation cancelling quicker, add extra balance cancelling check after each page read in relocate_file_extent_cluster(). Cleanup and error handling uses the same mechanism as if the whole process finished Reviewed-by: Johannes Thumshirn Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/relocation.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 0238801e6408..a4edb821990f 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -3445,6 +3445,10 @@ static int relocate_file_extent_cluster(struct inode *inode, btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE); balance_dirty_pages_ratelimited(inode->i_mapping); btrfs_throttle(fs_info); + if (btrfs_should_cancel_balance(fs_info)) { + ret = -ECANCELED; + goto out; + } } WARN_ON(nr != cluster->nr); out: @@ -4259,6 +4263,14 @@ restart: backref_cache_cleanup(&rc->backref_cache); btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1); + /* + * Even in the case when the relocation is cancelled, we should all go + * through prepare_to_merge() and merge_reloc_roots(). + * + * For error (including cancelled balance), prepare_to_merge() will + * mark all reloc trees orphan, then queue them for cleanup in + * merge_reloc_roots() + */ err = prepare_to_merge(rc, err); merge_reloc_roots(rc); -- cgit v1.2.3-58-ga151