From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07886C2B9F4 for ; Thu, 17 Jun 2021 05:14:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C4E6B613CB for ; Thu, 17 Jun 2021 05:14:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229560AbhFQFRC (ORCPT ); Thu, 17 Jun 2021 01:17:02 -0400 Received: from smtp-out2.suse.de ([195.135.220.29]:38148 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229495AbhFQFRC (ORCPT ); Thu, 17 Jun 2021 01:17:02 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 7D0CA1FDB1 for ; Thu, 17 Jun 2021 05:14:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1623906894; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=oE3tOJnIhdQ30YiNBvnPK8vcRTIuB5mkp55kzcIsCAg=; b=qlrSJNF9j3t2GgXq85gm5UGqYTUnJ8rqDX+0vVAg+QpG44WLBCGV5iBTkH/6dydTYVfleH P+Uf7CO7AccWbxZiwxFu3nSmIRYBQqftFry8Lwfe90NLBV77IWGBRC1TPATIGcbl06CRDa xH5bNUsu4YjkMKcUsuK4QTiemnFJNNQ= Received: from adam-pc.lan (unknown [10.163.16.38]) by relay2.suse.de (Postfix) with ESMTP id 78DD0A3BB8 for ; Thu, 17 Jun 2021 05:14:53 +0000 (UTC) From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH v4 0/9] btrfs: compression: refactor and enhancement preparing for subpage compression support Date: Thu, 17 Jun 2021 13:14:41 +0800 Message-Id: <20210617051450.206704-1-wqu@suse.com> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org There are quite some problems in compression code: - Weird compressed_bio::pending_bios dance If we just don't want compressed_bio being freed halfway, we have more sane methods, just like btrfs_subpage::readers. So here we fix it by introducing compressed_bio::io_sectors to do the job. - BUG_ON()s inside btrfs_submit_compressed_*() Even they are just ENOMEM, we should handle them. With io_sectors introduced, we have a way to finish compressed_bio all by ourselves, as long as we haven't submitted last bio. If we have last bio submitted, then endio will handle it well. - Duplicated code for compressed bio allocation and submission Just small refactor can handle it - Stripe boundary is checked every time one page is added This is overkilled. Just learn from extent_io.c refactor which use bio_ctrl to do the boundary check only once for each bio. Although in compression context, we don't need extra checks in extent_io.c, thus we don't need bio_ctrl structure, but can afford to do it locally. - Dead code removal One dead comment and a new zombie function, btrfs_bio_fits_in_stripe(), can be removed now. Changelog: v2: - Rebased to latest misc-next - Fix a bug in btrfs_submit_compressed_write() where zoned write is not taken into consideration - Reuse the existing chunk mapping of btrfs_get_chunk_map() v3: - Fix a bug that zoned device can't even pass btrfs/001 This is because at endio time, bi_size for zoned device is always 0. We have to use bio_for_each_segment_all() to calculate the real bio size instead. In theory, it should also happen more frequently for non-zoned device, but no catch for all test cases (with "-o compress") except btrfs/011. - Fix btrfs/011 hang when tested with "-o compress" This is caused by checking both atomic value without protection. Checking two atomic values is no longer atomic. In fact, with compressed_bio::io_sectors introduced, pending_bios is only used to wait for any pending bio to finish in error path. Thus dec_and_test_compressed_bio() only need to check if io_sectors is zero - Fix a error that in error handling path, we may hang due to missing wake_up() in dec_and_test_compressed_bio() v4: - Use formal words for BUG_ON() removal patch titles - Remove compressed_bio::pending_bios As compressed_bio::pending_sectors can replace it completely - Remove unnecessary comments and BUG_ON()s - Use wait_var_event() APIs to reduce the memory overhead - Comments update to follow the same schema for moved comments Qu Wenruo (9): btrfs: remove a dead comment for btrfs_decompress_bio() btrfs: introduce compressed_bio::pending_sectors to trace compressed bio more elegantly btrfs: handle errors properly inside btrfs_submit_compressed_read() btrfs: handle errors properly inside btrfs_submit_compressed_write() btrfs: introduce submit_compressed_bio() for compression btrfs: introduce alloc_compressed_bio() for compression btrfs: make btrfs_submit_compressed_read() to determine stripe boundary at bio allocation time btrfs: make btrfs_submit_compressed_write() to determine stripe boundary at bio allocation time btrfs: remove unused function btrfs_bio_fits_in_stripe() fs/btrfs/compression.c | 587 +++++++++++++++++++++++------------------ fs/btrfs/compression.h | 4 +- fs/btrfs/ctree.h | 2 - fs/btrfs/inode.c | 42 --- 4 files changed, 336 insertions(+), 299 deletions(-) -- 2.32.0