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=-12.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 A995BC4727D for ; Wed, 30 Sep 2020 01:56:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 593622145D for ; Wed, 30 Sep 2020 01:56:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="c07LzLwa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729851AbgI3B4W (ORCPT ); Tue, 29 Sep 2020 21:56:22 -0400 Received: from mx2.suse.de ([195.135.220.15]:50056 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729843AbgI3B4V (ORCPT ); Tue, 29 Sep 2020 21:56:21 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1601430980; h=from:from:reply-to:subject:subject: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=HvFXedX2aANewbCvKqGgEfcvtnPnwaJHRwN+3JuD3Po=; b=c07LzLwaUAnr3peqTncJaUjs4GGoKBQS5JYqHW6a3jXNHmF5mRIc48yM7e0O8BJ79QzyyR qpuI+C1N0K7IJIJaz9KBtoj/yLH3rBMYkJT959N18sAClcY3y6uERjQAv5NNVTPw43IzT+ ro3Y8sKuhXGi36ZvBKg2mjy0dtWXKpk= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 53BE5AF99 for ; Wed, 30 Sep 2020 01:56:20 +0000 (UTC) From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH v3 17/49] btrfs: extent_io: extract the btree page submission code into its own helper function Date: Wed, 30 Sep 2020 09:55:07 +0800 Message-Id: <20200930015539.48867-18-wqu@suse.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200930015539.48867-1-wqu@suse.com> References: <20200930015539.48867-1-wqu@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org In btree_write_cache_pages() we have a btree page submission routine buried deeply into a nested loop. This patch will extract that part of code into a helper function, submit_btree_page(), to do the same work. Also, since submit_btree_page() now can return >0 for successfull extent buffer submission, remove the "ASSERT(ret <= 0);" line. Signed-off-by: Qu Wenruo --- fs/btrfs/extent_io.c | 116 +++++++++++++++++++++++++------------------ 1 file changed, 69 insertions(+), 47 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index e282eb63ad1b..6b925094608c 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -3988,10 +3988,75 @@ static noinline_for_stack int write_one_eb(struct extent_buffer *eb, return ret; } +/* + * A helper to submit a btree page. + * + * This function is not always submitting the page, as we only submit the full + * extent buffer in a batch. + * + * @page: The btree page + * @prev_eb: Previous extent buffer, to determine if we need to submit + * this page. + * + * Return >0 if we have submitted the extent buffer successfully. + * Return 0 if we don't need to do anything for the page. + * Return <0 for fatal error. + */ +static int submit_btree_page(struct page *page, struct writeback_control *wbc, + struct extent_page_data *epd, + struct extent_buffer **prev_eb) +{ + struct address_space *mapping = page->mapping; + struct extent_buffer *eb; + int ret; + + if (!PagePrivate(page)) + return 0; + + spin_lock(&mapping->private_lock); + if (!PagePrivate(page)) { + spin_unlock(&mapping->private_lock); + return 0; + } + + eb = (struct extent_buffer *)page->private; + + /* + * Shouldn't happen and normally this would be a BUG_ON but no sense + * in crashing the users box for something we can survive anyway. + */ + if (WARN_ON(!eb)) { + spin_unlock(&mapping->private_lock); + return 0; + } + + if (eb == *prev_eb) { + spin_unlock(&mapping->private_lock); + return 0; + } + ret = atomic_inc_not_zero(&eb->refs); + spin_unlock(&mapping->private_lock); + if (!ret) + return 0; + + *prev_eb = eb; + + ret = lock_extent_buffer_for_io(eb, epd); + if (ret <= 0) { + free_extent_buffer(eb); + return ret; + } + ret = write_one_eb(eb, wbc, epd); + free_extent_buffer(eb); + if (ret < 0) + return ret; + return 1; +} + int btree_write_cache_pages(struct address_space *mapping, struct writeback_control *wbc) { - struct extent_buffer *eb, *prev_eb = NULL; + struct extent_buffer *prev_eb = NULL; struct extent_page_data epd = { .bio = NULL, .extent_locked = 0, @@ -4037,55 +4102,13 @@ int btree_write_cache_pages(struct address_space *mapping, for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; - if (!PagePrivate(page)) - continue; - - spin_lock(&mapping->private_lock); - if (!PagePrivate(page)) { - spin_unlock(&mapping->private_lock); - continue; - } - - eb = (struct extent_buffer *)page->private; - - /* - * Shouldn't happen and normally this would be a BUG_ON - * but no sense in crashing the users box for something - * we can survive anyway. - */ - if (WARN_ON(!eb)) { - spin_unlock(&mapping->private_lock); - continue; - } - - if (eb == prev_eb) { - spin_unlock(&mapping->private_lock); - continue; - } - - ret = atomic_inc_not_zero(&eb->refs); - spin_unlock(&mapping->private_lock); - if (!ret) - continue; - - prev_eb = eb; - ret = lock_extent_buffer_for_io(eb, &epd); - if (!ret) { - free_extent_buffer(eb); + ret = submit_btree_page(page, wbc, &epd, &prev_eb); + if (ret == 0) continue; - } else if (ret < 0) { - done = 1; - free_extent_buffer(eb); - break; - } - - ret = write_one_eb(eb, wbc, &epd); - if (ret) { + if (ret < 0) { done = 1; - free_extent_buffer(eb); break; } - free_extent_buffer(eb); /* * the filesystem may choose to bump up nr_to_write. @@ -4106,7 +4129,6 @@ int btree_write_cache_pages(struct address_space *mapping, index = 0; goto retry; } - ASSERT(ret <= 0); if (ret < 0) { end_write_bio(&epd, ret); return ret; -- 2.28.0