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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED 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 6F2D3C433DF for ; Fri, 22 May 2020 02:53:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3D94D207D8 for ; Fri, 22 May 2020 02:53:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="TVYOaTk2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727770AbgEVCxY (ORCPT ); Thu, 21 May 2020 22:53:24 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:35174 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727055AbgEVCxY (ORCPT ); Thu, 21 May 2020 22:53:24 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04M2mVMM123383; Fri, 22 May 2020 02:53:20 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : from : to : cc : date : message-id : in-reply-to : references : mime-version : content-type : content-transfer-encoding; s=corp-2020-01-29; bh=FAO3H4DWyRjLYvBNdb2G9tFexwRSnmfFh30gHMiobTQ=; b=TVYOaTk2wJUykg4HTGUFhtPm9Bs1344SN8+5ZHIZEhvYNav+k/bau7VUzP7orMk9ZiM+ 0RssWinQKfiTXOYd+a093QaHlYGGhEhKFLSWLhtYbjjt5MIjBqM1rU+61UFc/95GN+7W aO7+VjjhxK2hhGAJeps8VhqanwVf2qSqIIzm4lRINqgKhcsEMs2kr1R0BLZjKXoTRT0c brG0bsyCM1SW2Yj7XrxTApP8CvqQghcdSGEsJ5zeYwvKBp18dO58CgTq5qPpCQSbVa1Y JMSbpwLGpg2S/eSUgu1haYiFv1l0fz7e1RRe2b+fdlrqDnNTyHZuZiX/+kl07g9Ye0ed 4w== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 3127krkk0d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 22 May 2020 02:53:20 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04M2nEZQ173910; Fri, 22 May 2020 02:53:19 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserp3020.oracle.com with ESMTP id 312t3d3vsj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 22 May 2020 02:53:19 +0000 Received: from abhmp0005.oracle.com (abhmp0005.oracle.com [141.146.116.11]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 04M2rIxb029849; Fri, 22 May 2020 02:53:18 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 21 May 2020 19:53:17 -0700 Subject: [PATCH 3/4] xfs: refactor xfs_iomap_prealloc_size From: "Darrick J. Wong" To: darrick.wong@oracle.com Cc: Christoph Hellwig , linux-xfs@vger.kernel.org, hch@infradead.org, bfoster@redhat.com Date: Thu, 21 May 2020 19:53:16 -0700 Message-ID: <159011599650.76931.9345570053700795571.stgit@magnolia> In-Reply-To: <159011597442.76931.7800023221007221972.stgit@magnolia> References: <159011597442.76931.7800023221007221972.stgit@magnolia> User-Agent: StGit/0.19 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9628 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 spamscore=0 mlxlogscore=999 phishscore=0 mlxscore=0 malwarescore=0 suspectscore=1 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005220021 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9628 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 phishscore=0 spamscore=0 bulkscore=0 clxscore=1015 priorityscore=1501 mlxscore=0 impostorscore=0 suspectscore=1 mlxlogscore=999 malwarescore=0 cotscore=-2147483648 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005220021 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: Darrick J. Wong Refactor xfs_iomap_prealloc_size to be the function that dynamically computes the per-file preallocation size by moving the allocsize= case to the caller. Break up the huge comment preceding the function to annotate the relevant parts of the code, and remove the impossible check_writeio case. Suggested-by: Christoph Hellwig Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_iomap.c | 83 ++++++++++++++++++++++------------------------------ 1 file changed, 35 insertions(+), 48 deletions(-) diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 6a308af93893..d8fa5519c761 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -352,22 +352,10 @@ xfs_quota_calc_throttle( } /* - * If we are doing a write at the end of the file and there are no allocations - * past this one, then extend the allocation out to the file system's write - * iosize. - * * If we don't have a user specified preallocation size, dynamically increase * the preallocation size as the size of the file grows. Cap the maximum size * at a single extent or less if the filesystem is near full. The closer the - * filesystem is to full, the smaller the maximum prealocation. - * - * As an exception we don't do any preallocation at all if the file is smaller - * than the minimum preallocation and we are using the default dynamic - * preallocation scheme, as it is likely this is the only write to the file that - * is going to be done. - * - * We clean up any extra space left over when the file is closed in - * xfs_inactive(). + * filesystem is to being full, the smaller the maximum preallocation. */ STATIC xfs_fsblock_t xfs_iomap_prealloc_size( @@ -389,41 +377,28 @@ xfs_iomap_prealloc_size( int shift = 0; int qshift = 0; - if (offset + count <= XFS_ISIZE(ip)) - return 0; - - if (!(mp->m_flags & XFS_MOUNT_ALLOCSIZE) && - (XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_allocsize_blocks))) + /* + * As an exception we don't do any preallocation at all if the file is + * smaller than the minimum preallocation and we are using the default + * dynamic preallocation scheme, as it is likely this is the only write + * to the file that is going to be done. + */ + if (XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_allocsize_blocks)) return 0; /* - * If an explicit allocsize is set, the file is small, or we - * are writing behind a hole, then use the minimum prealloc: + * Use the minimum preallocation size for small files or if we are + * writing right after a hole. */ - if ((mp->m_flags & XFS_MOUNT_ALLOCSIZE) || - XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_dalign) || + if (XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_dalign) || !xfs_iext_peek_prev_extent(ifp, icur, &prev) || prev.br_startoff + prev.br_blockcount < offset_fsb) return mp->m_allocsize_blocks; /* - * Determine the initial size of the preallocation. We are beyond the - * current EOF here, but we need to take into account whether this is - * a sparse write or an extending write when determining the - * preallocation size. Hence we need to look up the extent that ends - * at the current write offset and use the result to determine the - * preallocation size. - * - * If the extent is a hole, then preallocation is essentially disabled. - * Otherwise we take the size of the preceding data extents as the basis - * for the preallocation size. Note that we don't care if the previous - * extents are written or not. - * - * If the size of the extents is greater than half the maximum extent - * length, then use the current offset as the basis. This ensures that - * for large files the preallocation size always extends to MAXEXTLEN - * rather than falling short due to things like stripe unit/width - * alignment of real extents. + * Take the size of the preceding data extents as the basis for the + * preallocation size. Note that we don't care if the previous extents + * are written or not. */ plen = prev.br_blockcount; while (xfs_iext_prev_extent(ifp, &ncur, &got)) { @@ -434,19 +409,25 @@ xfs_iomap_prealloc_size( plen += got.br_blockcount; prev = got; } + + /* + * If the size of the extents is greater than half the maximum extent + * length, then use the current offset as the basis. This ensures that + * for large files the preallocation size always extends to MAXEXTLEN + * rather than falling short due to things like stripe unit/width + * alignment of real extents. + */ alloc_blocks = plen * 2; if (alloc_blocks > MAXEXTLEN) alloc_blocks = XFS_B_TO_FSB(mp, offset); - if (!alloc_blocks) - goto check_writeio; qblocks = alloc_blocks; /* * MAXEXTLEN is not a power of two value but we round the prealloc down * to the nearest power of two value after throttling. To prevent the - * round down from unconditionally reducing the maximum supported prealloc - * size, we round up first, apply appropriate throttling, round down and - * cap the value to MAXEXTLEN. + * round down from unconditionally reducing the maximum supported + * prealloc size, we round up first, apply appropriate throttling, + * round down and cap the value to MAXEXTLEN. */ alloc_blocks = XFS_FILEOFF_MIN(roundup_pow_of_two(MAXEXTLEN), alloc_blocks); @@ -507,7 +488,6 @@ xfs_iomap_prealloc_size( */ while (alloc_blocks && alloc_blocks >= freesp) alloc_blocks >>= 4; -check_writeio: if (alloc_blocks < mp->m_allocsize_blocks) alloc_blocks = mp->m_allocsize_blocks; trace_xfs_iomap_prealloc_size(ip, alloc_blocks, shift, @@ -974,9 +954,16 @@ xfs_buffered_write_iomap_begin( if (error) goto out_unlock; - if (eof) { - prealloc_blocks = xfs_iomap_prealloc_size(ip, allocfork, offset, - count, &icur); + if (eof && offset + count > XFS_ISIZE(ip)) { + /* + * Determine the initial size of the preallocation. + * We clean up any extra preallocation when the file is closed. + */ + if (mp->m_flags & XFS_MOUNT_ALLOCSIZE) + prealloc_blocks = mp->m_allocsize_blocks; + else + prealloc_blocks = xfs_iomap_prealloc_size(ip, allocfork, + offset, count, &icur); if (prealloc_blocks) { xfs_extlen_t align; xfs_off_t end_offset;