From patchwork Fri Nov 20 15:16:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 11921043 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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 EDAA0C83013 for ; Fri, 20 Nov 2020 15:16:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AB8232222F for ; Fri, 20 Nov 2020 15:16:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="a/Na8NFC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729496AbgKTPQq (ORCPT ); Fri, 20 Nov 2020 10:16:46 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:59959 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729503AbgKTPQo (ORCPT ); Fri, 20 Nov 2020 10:16:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1605885403; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TVQXfMRgcYF74aRdJN1EqRV7ahJ/l5qJeAzL/vDKTfE=; b=a/Na8NFCIDkTFU9vMYbc22sQw8twQ+xNLIcXOYv6efntw1GOeRMW5GvC2oHegNgD7yJMS4 +euo+GaDoSob5/FWLE7nDhoVdDXPhS6CS/LdUm6FHn4P/TseAxUbfPLdl41i4nXoT2Dg49 xyXiM44i2N4nsceFanhCvnDDMV5mkj0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-268-Szi2evUlMv6SjKaJbu6RXg-1; Fri, 20 Nov 2020 10:16:38 -0500 X-MC-Unique: Szi2evUlMv6SjKaJbu6RXg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0B575100C618; Fri, 20 Nov 2020 15:16:37 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-112-246.rdu2.redhat.com [10.10.112.246]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8FA155C233; Fri, 20 Nov 2020 15:16:25 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [RFC PATCH 64/76] afs: Extract writeback extension into its own function From: David Howells To: Trond Myklebust , Anna Schumaker , Steve French , Dominique Martinet Cc: dhowells@redhat.com, Jeff Layton , Matthew Wilcox , Alexander Viro , linux-cachefs@redhat.com, linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Fri, 20 Nov 2020 15:16:24 +0000 Message-ID: <160588538471.3465195.782513375683399583.stgit@warthog.procyon.org.uk> In-Reply-To: <160588455242.3465195.3214733858273019178.stgit@warthog.procyon.org.uk> References: <160588455242.3465195.3214733858273019178.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org Extract writeback extension into its own function to break up the writeback function a bit. Signed-off-by: David Howells --- fs/afs/write.c | 109 ++++++++++++++++++++++++++++++++++---------------------- 1 file changed, 67 insertions(+), 42 deletions(-) diff --git a/fs/afs/write.c b/fs/afs/write.c index e1791de90478..89c804bfe253 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -490,47 +490,25 @@ static int afs_store_data(struct afs_vnode *vnode, struct iov_iter *iter, } /* - * Synchronously write back the locked page and any subsequent non-locked dirty - * pages. + * Extend the region to be written back to include subsequent contiguously + * dirty pages if possible, but don't sleep while doing so. + * + * If this page holds new content, then we can include filler zeros in the + * writeback. */ -static int afs_write_back_from_locked_page(struct address_space *mapping, - struct writeback_control *wbc, - struct page *primary_page, - pgoff_t final_page) +static void afs_extend_writeback(struct address_space *mapping, + struct afs_vnode *vnode, + long *_count, + pgoff_t start, + pgoff_t final_page, + unsigned *_offset, + unsigned *_to, + bool new_content) { - struct afs_vnode *vnode = AFS_FS_I(mapping->host); - struct iov_iter iter; struct page *pages[8], *page; - unsigned long count, priv; - unsigned n, offset, to, f, t; - pgoff_t start, first, last; - loff_t i_size, pos, end; - int loop, ret; - - _enter(",%lx", primary_page->index); - - count = 1; - if (test_set_page_writeback(primary_page)) - BUG(); - - /* Find all consecutive lockable dirty pages that have contiguous - * written regions, stopping when we find a page that is not - * immediately lockable, is not dirty or is missing, or we reach the - * end of the range. - */ - start = primary_page->index; - priv = page_private(primary_page); - offset = afs_page_dirty_from(primary_page, priv); - to = afs_page_dirty_to(primary_page, priv); - trace_afs_page_dirty(vnode, tracepoint_string("store"), primary_page); - - WARN_ON(offset == to); - if (offset == to) - trace_afs_page_dirty(vnode, tracepoint_string("WARN"), primary_page); - - if (start >= final_page || - (to < PAGE_SIZE && !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags))) - goto no_more; + unsigned long count = *_count, priv; + unsigned offset = *_offset, to = *_to, n, f, t; + int loop; start++; do { @@ -551,8 +529,7 @@ static int afs_write_back_from_locked_page(struct address_space *mapping, for (loop = 0; loop < n; loop++) { page = pages[loop]; - if (to != PAGE_SIZE && - !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) + if (to != PAGE_SIZE && !new_content) break; if (page->index > final_page) break; @@ -566,8 +543,7 @@ static int afs_write_back_from_locked_page(struct address_space *mapping, priv = page_private(page); f = afs_page_dirty_from(page, priv); t = afs_page_dirty_to(page, priv); - if (f != 0 && - !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) { + if (f != 0 && !new_content) { unlock_page(page); break; } @@ -593,6 +569,55 @@ static int afs_write_back_from_locked_page(struct address_space *mapping, } while (start <= final_page && count < 65536); no_more: + *_count = count; + *_offset = offset; + *_to = to; +} + +/* + * Synchronously write back the locked page and any subsequent non-locked dirty + * pages. + */ +static int afs_write_back_from_locked_page(struct address_space *mapping, + struct writeback_control *wbc, + struct page *primary_page, + pgoff_t final_page) +{ + struct afs_vnode *vnode = AFS_FS_I(mapping->host); + struct iov_iter iter; + unsigned long count, priv; + unsigned offset, to; + pgoff_t start, first, last; + loff_t i_size, pos, end; + bool new_content = test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags); + int ret; + + _enter(",%lx", primary_page->index); + + count = 1; + if (test_set_page_writeback(primary_page)) + BUG(); + + /* Find all consecutive lockable dirty pages that have contiguous + * written regions, stopping when we find a page that is not + * immediately lockable, is not dirty or is missing, or we reach the + * end of the range. + */ + start = primary_page->index; + priv = page_private(primary_page); + offset = afs_page_dirty_from(primary_page, priv); + to = afs_page_dirty_to(primary_page, priv); + trace_afs_page_dirty(vnode, tracepoint_string("store"), primary_page); + + WARN_ON(offset == to); + if (offset == to) + trace_afs_page_dirty(vnode, tracepoint_string("WARN"), primary_page); + + if (start < final_page && + (to == PAGE_SIZE || new_content)) + afs_extend_writeback(mapping, vnode, &count, start, final_page, + &offset, &to, new_content); + /* We now have a contiguous set of dirty pages, each with writeback * set; the first page is still locked at this point, but all the rest * have been unlocked.