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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, 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 394A9C11F68 for ; Tue, 13 Jul 2021 06:15:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 267BB61183 for ; Tue, 13 Jul 2021 06:15:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233926AbhGMGS3 (ORCPT ); Tue, 13 Jul 2021 02:18:29 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:36750 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233814AbhGMGS2 (ORCPT ); Tue, 13 Jul 2021 02:18:28 -0400 Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 94544221D2 for ; Tue, 13 Jul 2021 06:15:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1626156938; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bRiuEyXkkun8ut4UK6s93X6ayeghGficPM397ZX/HXI=; b=ET/JJSYYTLTFV3FvarnhV6hpWDjCn39JzzzXa8yKW0HpqRZIZZ5b/O+yoC7AqhN1e/NS73 VxoDgmjIpJSZ83VGBD+YzNmnLddwDFwKBh0zjo+dcjc1uKKyjbwF0SidS59H+I1WFce/3q 8adA0wS5Qyh2hWDcvF/MgH+YIRlENUc= Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap1.suse-dmz.suse.de (Postfix) with ESMTPS id D1A7E139AC for ; Tue, 13 Jul 2021 06:15:37 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap1.suse-dmz.suse.de with ESMTPSA id yPu8JIkv7WB0XgAAGKfGzw (envelope-from ) for ; Tue, 13 Jul 2021 06:15:37 +0000 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH 15/27] btrfs: refactor submit_compressed_extents() Date: Tue, 13 Jul 2021 14:15:04 +0800 Message-Id: <20210713061516.163318-16-wqu@suse.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210713061516.163318-1-wqu@suse.com> References: <20210713061516.163318-1-wqu@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org We have a big hunk of code inside a while() loop, with tons of strange jump for error handling. It's definitely not to the code standard of today. Move the code into a new function, submit_one_async_extent(). Since we're here, also do the following modifications: - Comment style change To follow the current scheme - Don't fallback to non-compressed write then hitting ENOSPC If we hit ENOSPC for compressed write, how could we reserve more space for non-compressed write? Thus we go error path directly. This removes the retry: label. - Add more comment for super long parameter list Explain which parameter is for, so we don't need to check the prototype. - Move the error handling to submit_one_async_extent() Thus no strange code like: out_free: ... goto again; Signed-off-by: Qu Wenruo --- fs/btrfs/inode.c | 278 +++++++++++++++++++++++------------------------ 1 file changed, 137 insertions(+), 141 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index cb6cb99eb454..7931c4a5bc5d 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -838,163 +838,129 @@ static void free_async_extent_pages(struct async_extent *async_extent) async_extent->pages = NULL; } -/* - * phase two of compressed writeback. This is the ordered portion - * of the code, which only gets called in the order the work was - * queued. We walk all the async extents created by compress_file_range - * and send them down to the disk. - */ -static noinline void submit_compressed_extents(struct async_chunk *async_chunk) +static int submit_one_async_extent(struct btrfs_inode *inode, + struct async_chunk *async_chunk, + struct async_extent *async_extent, + u64 *alloc_hint) { - struct btrfs_inode *inode = BTRFS_I(async_chunk->inode); - struct btrfs_fs_info *fs_info = inode->root->fs_info; - struct async_extent *async_extent; - u64 alloc_hint = 0; + struct extent_io_tree *io_tree = &inode->io_tree; + struct btrfs_root *root = inode->root; + struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_key ins; struct extent_map *em; - struct btrfs_root *root = inode->root; - struct extent_io_tree *io_tree = &inode->io_tree; int ret = 0; + u64 start = async_extent->start; + u64 end = async_extent->start + async_extent->ram_size - 1; -again: - while (!list_empty(&async_chunk->extents)) { - async_extent = list_entry(async_chunk->extents.next, - struct async_extent, list); - list_del(&async_extent->list); - -retry: - lock_extent(io_tree, async_extent->start, - async_extent->start + async_extent->ram_size - 1); - /* did the compression code fall back to uncompressed IO? */ - if (!async_extent->pages) { - int page_started = 0; - unsigned long nr_written = 0; - - /* allocate blocks */ - ret = cow_file_range(inode, async_chunk->locked_page, - async_extent->start, - async_extent->start + - async_extent->ram_size - 1, - &page_started, &nr_written, 0); - - /* JDM XXX */ + lock_extent(io_tree, start, end); - /* - * if page_started, cow_file_range inserted an - * inline extent and took care of all the unlocking - * and IO for us. Otherwise, we need to submit - * all those pages down to the drive. - */ - if (!page_started && !ret) - extent_write_locked_range(&inode->vfs_inode, - async_extent->start, - async_extent->start + - async_extent->ram_size - 1, - WB_SYNC_ALL); - else if (ret && async_chunk->locked_page) - unlock_page(async_chunk->locked_page); - kfree(async_extent); - cond_resched(); - continue; - } - - ret = btrfs_reserve_extent(root, async_extent->ram_size, - async_extent->compressed_size, - async_extent->compressed_size, - 0, alloc_hint, &ins, 1, 1); - if (ret) { - free_async_extent_pages(async_extent); - - if (ret == -ENOSPC) { - unlock_extent(io_tree, async_extent->start, - async_extent->start + - async_extent->ram_size - 1); - - /* - * we need to redirty the pages if we decide to - * fallback to uncompressed IO, otherwise we - * will not submit these pages down to lower - * layers. - */ - extent_range_redirty_for_io(&inode->vfs_inode, - async_extent->start, - async_extent->start + - async_extent->ram_size - 1); + /* We have fall back to uncompressed write */ + if (!async_extent->pages) { + int page_started = 0; + unsigned long nr_written = 0; - goto retry; - } - goto out_free; - } /* - * here we're doing allocation and writeback of the - * compressed pages + * Call cow_file_range() to run the delalloc range directly, + * since we won't go to nocow or async path again. */ - em = create_io_em(inode, async_extent->start, - async_extent->ram_size, /* len */ - async_extent->start, /* orig_start */ - ins.objectid, /* block_start */ - ins.offset, /* block_len */ - ins.offset, /* orig_block_len */ - async_extent->ram_size, /* ram_bytes */ - async_extent->compress_type, - BTRFS_ORDERED_COMPRESSED); - if (IS_ERR(em)) - /* ret value is not necessary due to void function */ - goto out_free_reserve; - free_extent_map(em); - - ret = btrfs_add_ordered_extent_compress(inode, - async_extent->start, - ins.objectid, - async_extent->ram_size, - ins.offset, - async_extent->compress_type); - if (ret) { - btrfs_drop_extent_cache(inode, async_extent->start, - async_extent->start + - async_extent->ram_size - 1, 0); - goto out_free_reserve; - } - btrfs_dec_block_group_reservations(fs_info, ins.objectid); - + ret = cow_file_range(inode, async_chunk->locked_page, + start, end, &page_started, &nr_written, 0); /* - * clear dirty, set writeback and unlock the pages. + * If @page_started, cow_file_range() inserted an + * inline extent and took care of all the unlocking + * and IO for us. Otherwise, we need to submit + * all those pages down to the drive. */ - extent_clear_unlock_delalloc(inode, async_extent->start, - async_extent->start + - async_extent->ram_size - 1, - NULL, EXTENT_LOCKED | EXTENT_DELALLOC, - PAGE_UNLOCK | PAGE_START_WRITEBACK); - if (btrfs_submit_compressed_write(inode, async_extent->start, - async_extent->ram_size, - ins.objectid, - ins.offset, async_extent->pages, - async_extent->nr_pages, - async_chunk->write_flags, - async_chunk->blkcg_css)) { - const u64 start = async_extent->start; - const u64 end = start + async_extent->ram_size - 1; - - btrfs_writepage_endio_finish_ordered(inode, NULL, start, - end, 0); - - extent_clear_unlock_delalloc(inode, start, end, NULL, 0, - PAGE_END_WRITEBACK | - PAGE_SET_ERROR); - free_async_extent_pages(async_extent); - } - alloc_hint = ins.objectid + ins.offset; + if (!page_started && !ret) + extent_write_locked_range(&inode->vfs_inode, start, + end, WB_SYNC_ALL); + else if (ret && async_chunk->locked_page) + unlock_page(async_chunk->locked_page); kfree(async_extent); - cond_resched(); + return ret; + } + + ret = btrfs_reserve_extent(root, async_extent->ram_size, + async_extent->compressed_size, + async_extent->compressed_size, + 0, *alloc_hint, &ins, 1, 1); + if (ret) { + free_async_extent_pages(async_extent); + /* + * Here we used to try again by going back to non-compressed + * path for ENOSPC. + * But we can't reserve space even for compressed size, how + * could it work for uncompressed size which requires larger + * size? + * So here we directly go error path. + */ + goto out_free; + } + + /* + * Here we're doing allocation and writeback of the + * compressed pages + */ + em = create_io_em(inode, start, + async_extent->ram_size, /* len */ + start, /* orig_start */ + ins.objectid, /* block_start */ + ins.offset, /* block_len */ + ins.offset, /* orig_block_len */ + async_extent->ram_size, /* ram_bytes */ + async_extent->compress_type, + BTRFS_ORDERED_COMPRESSED); + if (IS_ERR(em)) { + ret = PTR_ERR(em); + goto out_free_reserve; + } + free_extent_map(em); + + ret = btrfs_add_ordered_extent_compress(inode, start, /* file_offset */ + ins.objectid, /* disk_bytenr */ + async_extent->ram_size, /* num_bytes */ + ins.offset, /* disk_num_bytes */ + async_extent->compress_type); + if (ret) { + btrfs_drop_extent_cache(inode, start, end, 0); + goto out_free_reserve; } - return; + btrfs_dec_block_group_reservations(fs_info, ins.objectid); + + /* + * clear dirty, set writeback and unlock the pages. + */ + extent_clear_unlock_delalloc(inode, start, end, + NULL, EXTENT_LOCKED | EXTENT_DELALLOC, + PAGE_UNLOCK | PAGE_START_WRITEBACK); + if (btrfs_submit_compressed_write(inode, start, /* file_offset */ + async_extent->ram_size, /* num_bytes */ + ins.objectid, /* disk_bytenr */ + ins.offset, /* compressed_len */ + async_extent->pages, /* compressed_pages */ + async_extent->nr_pages, + async_chunk->write_flags, + async_chunk->blkcg_css)) { + const u64 start = async_extent->start; + const u64 end = start + async_extent->ram_size - 1; + + btrfs_writepage_endio_finish_ordered(inode, NULL, start, + end, 0); + + extent_clear_unlock_delalloc(inode, start, end, NULL, 0, + PAGE_END_WRITEBACK | + PAGE_SET_ERROR); + free_async_extent_pages(async_extent); + } + *alloc_hint = ins.objectid + ins.offset; + kfree(async_extent); + return ret; + out_free_reserve: btrfs_dec_block_group_reservations(fs_info, ins.objectid); btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); out_free: - extent_clear_unlock_delalloc(inode, async_extent->start, - async_extent->start + - async_extent->ram_size - 1, + extent_clear_unlock_delalloc(inode, start, end, NULL, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, @@ -1002,7 +968,37 @@ static noinline void submit_compressed_extents(struct async_chunk *async_chunk) PAGE_END_WRITEBACK | PAGE_SET_ERROR); free_async_extent_pages(async_extent); kfree(async_extent); - goto again; + return ret; +} + +/* + * phase two of compressed writeback. This is the ordered portion + * of the code, which only gets called in the order the work was + * queued. We walk all the async extents created by compress_file_range + * and send them down to the disk. + */ +static noinline void submit_compressed_extents(struct async_chunk *async_chunk) +{ + struct btrfs_inode *inode = BTRFS_I(async_chunk->inode); + struct btrfs_fs_info *fs_info = inode->root->fs_info; + struct async_extent *async_extent; + u64 alloc_hint = 0; + int ret = 0; + + while (!list_empty(&async_chunk->extents)) { + async_extent = list_entry(async_chunk->extents.next, + struct async_extent, list); + list_del(&async_extent->list); + + ret = submit_one_async_extent(inode, async_chunk, async_extent, + &alloc_hint); + /* Just for developer */ + btrfs_debug(fs_info, +"async extent submission failed root=%lld inode=%llu start=%llu len=%llu ret=%d", + inode->root->root_key.objectid, + btrfs_ino(inode), async_extent->start, + async_extent->ram_size, ret); + } } static u64 get_extent_allocation_hint(struct btrfs_inode *inode, u64 start, -- 2.32.0