From patchwork Mon Feb 17 06:16:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 11385255 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0C08E930 for ; Mon, 17 Feb 2020 06:17:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E155020679 for ; Mon, 17 Feb 2020 06:17:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726415AbgBQGRF (ORCPT ); Mon, 17 Feb 2020 01:17:05 -0500 Received: from mx2.suse.de ([195.135.220.15]:41800 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725835AbgBQGRE (ORCPT ); Mon, 17 Feb 2020 01:17:04 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id EA553AAC2 for ; Mon, 17 Feb 2020 06:17:02 +0000 (UTC) From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH v3 2/3] btrfs: relocation: Check cancel request after each data page read Date: Mon, 17 Feb 2020 14:16:53 +0800 Message-Id: <20200217061654.65567-3-wqu@suse.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200217061654.65567-1-wqu@suse.com> References: <20200217061654.65567-1-wqu@suse.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org 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 | } So to make data relocation cancelling quicker, here add extra balance cancelling check after each page read in relocate_file_extent_cluster(). Also add a comment explaining how the cancelling/error handling works. Signed-off-by: Qu Wenruo Reviewed-by: Johannes Thumshirn --- fs/btrfs/relocation.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 475479d50cc3..dc97fdd58c3d 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -3396,6 +3396,10 @@ 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 (should_cancel_balance(fs_info)) { + ret = -ECANCELED; + goto out; + } } WARN_ON(nr != cluster->nr); out: @@ -4208,6 +4212,14 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc) backref_cache_cleanup(&rc->backref_cache); btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1); + /* + * Even when the relocation is cancelled, we should all go throught + * prepare_to_merge() and merge_reloc_roots(). + * + * For error (including cancelled balance), prepare_to_merge() will + * mark all reloc tree orphan, then queue them for cleanup in + * merge_reloc_roots() + */ err = prepare_to_merge(rc, err); merge_reloc_roots(rc);