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=-8.4 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,USER_AGENT_SANE_1 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 CD3B6C3F2D1 for ; Tue, 3 Mar 2020 17:07:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 869B32083E for ; Tue, 3 Mar 2020 17:07:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="VFqXBDMs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729755AbgCCRHO (ORCPT ); Tue, 3 Mar 2020 12:07:14 -0500 Received: from aserp2120.oracle.com ([141.146.126.78]:55564 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729235AbgCCRHO (ORCPT ); Tue, 3 Mar 2020 12:07:14 -0500 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 023Gs9P5126904; Tue, 3 Mar 2020 17:07:10 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2020-01-29; bh=qepxz3iIUf/WR03RWLfaHmBnLLs+/fcP1Usg1uyi/G4=; b=VFqXBDMs251RMqSfwYMwQRsBUkPWQ6OQasIi/78Ky9umNLJx2cp/86CemQ/ao1dvZ+aL K1JXpsTMmlvQ6enu37WtfvBWvoE/JkXbjQglC8JraUgrCRO3AAu9T4nQ+dJm9LGu1cld +zj/E2101Q1N3AwOAA1y7VS785t/EP6OCC9P76lykReQfcUNQgD4es1JCAZBN+Y7VkKR 7mXbdzaWrYMkoO7+i2NNkp+0TjjZFmLmcy/8QRpamLYJrZF1Hajk22Exn4C7ALmsJphC ADMArlceNIptM6EcOeCKTyhviNEh1Jo++zMmccSAy4ZZ4OxsGzd5R7IZEPp0qCdEVDpz iA== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by aserp2120.oracle.com with ESMTP id 2yffwqrngv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 03 Mar 2020 17:07:09 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 023GmfeD088263; Tue, 3 Mar 2020 17:07:09 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userp3030.oracle.com with ESMTP id 2yg1em75uc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 03 Mar 2020 17:07:08 +0000 Received: from abhmp0002.oracle.com (abhmp0002.oracle.com [141.146.116.8]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 023H77lw028199; Tue, 3 Mar 2020 17:07:07 GMT Received: from [192.168.1.223] (/67.1.3.112) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 03 Mar 2020 09:07:06 -0800 Subject: Re: [PATCH v7 14/19] xfs: Add delay ready attr set routines To: Chandan Rajendra Cc: linux-xfs@vger.kernel.org References: <20200223020611.1802-1-allison.henderson@oracle.com> <20200223020611.1802-15-allison.henderson@oracle.com> <6212160.4XXo0ysdIk@localhost.localdomain> From: Allison Collins Message-ID: <7f0c5a2d-371b-6eca-ccab-9ec0947dee30@oracle.com> Date: Tue, 3 Mar 2020 10:07:05 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <6212160.4XXo0ysdIk@localhost.localdomain> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9549 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 suspectscore=0 spamscore=0 mlxlogscore=999 malwarescore=0 bulkscore=0 mlxscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2003030116 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9549 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 lowpriorityscore=0 spamscore=0 impostorscore=0 malwarescore=0 mlxlogscore=999 mlxscore=0 suspectscore=0 phishscore=0 clxscore=1015 bulkscore=0 adultscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2003030116 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On 3/3/20 6:41 AM, Chandan Rajendra wrote: > On Sunday, February 23, 2020 7:36 AM Allison Collins wrote: >> This patch modifies the attr set routines to be delay ready. This means they no >> longer roll or commit transactions, but instead return -EAGAIN to have the calling >> routine roll and refresh the transaction. In this series, xfs_attr_set_args has >> become xfs_attr_set_iter, which uses a state machine like switch to keep track of >> where it was when EAGAIN was returned. >> >> Part of xfs_attr_leaf_addname has been factored out into a new helper function >> xfs_attr_leaf_try_add to allow transaction cycling between the two routines. >> >> Two new helper functions have been added: xfs_attr_rmtval_set_init and >> xfs_attr_rmtval_set_blk. They provide a subset of logic similar to >> xfs_attr_rmtval_set, but they store the current block in the delay attr >> context to allow the caller to roll the transaction between allocations. This helps >> to simplify and consolidate code used by xfs_attr_leaf_addname and >> xfs_attr_node_addname. Finally, xfs_attr_set_args has become a simple loop to >> refresh the transaction until the operation is completed. >> >> Below is a state machine diagram for attr set operations. The XFS_DAS_* states >> indicate places where the function would return -EAGAIN, and then immediately >> resume from after being recalled by the calling function. States marked as a >> "subroutine state" indicate that they belong to a subroutine, and so the calling >> function needs to pass them back to that subroutine to allow it to finish where it >> left off. But they otherwise do not have a role in the calling function other >> than just passing through. >> >> xfs_attr_set_iter() >> │ >> v >> need to upgrade >> from sf to leaf? ──n─┐ >> │ │ >> y │ >> │ │ >> V │ >> XFS_DAS_ADD_LEAF │ >> │ │ >> v │ >> ┌──────n── fork has <──────┘ >> │ only 1 blk? >> │ │ >> │ y >> │ │ >> │ v >> │ xfs_attr_leaf_try_add() >> │ │ >> │ v >> │ had enough >> ├──────n── space? >> │ │ >> │ y >> │ │ >> │ v >> │ XFS_DAS_FOUND_LBLK ──┐ >> │ │ >> │ XFS_DAS_FLIP_LFLAG ──┤ >> │ (subroutine state) │ >> │ │ >> │ XFS_DAS_ALLOC_LEAF ──┤ >> │ (subroutine state) │ >> │ └─>xfs_attr_leaf_addname() >> │ │ >> │ v >> │ ┌─────n── need to >> │ │ alloc blks? >> │ │ │ >> │ │ y >> │ │ │ >> │ │ v >> │ │ ┌─>XFS_DAS_ALLOC_LEAF >> │ │ │ │ >> │ │ │ v >> │ │ └──y── need to alloc >> │ │ more blocks? >> │ │ │ >> │ │ n >> │ │ │ >> │ │ v >> │ │ was this >> │ └────────> a rename? ──n─┐ >> │ │ │ >> │ y │ >> │ │ │ >> │ v │ >> │ flip incomplete │ >> │ flag │ >> │ │ │ >> │ v │ >> │ ┌─>XFS_DAS_FLIP_LFLAG │ >> │ │ │ │ >> │ │ v │ >> │ │ remove │ >> │ │ old name │ >> │ │ │ │ >> │ │ v │ >> │ └────y── more to │ >> │ remove │ >> │ │ │ >> │ n │ >> │ │ │ >> │ v │ >> │ done <──────┘ >> └────> XFS_DAS_LEAF_TO_NODE ─┐ >> │ >> XFS_DAS_FOUND_NBLK ──┤ >> (subroutine state) │ >> │ >> XFS_DAS_ALLOC_NODE ──┤ >> (subroutine state) │ >> │ >> XFS_DAS_FLIP_NFLAG ──┤ >> (subroutine state) │ >> │ >> └─>xfs_attr_node_addname() >> │ >> v >> find space to store >> attr. Split if needed >> │ >> v >> XFS_DAS_FOUND_NBLK >> │ >> v >> ┌─────n── need to >> │ alloc blks? >> │ │ >> │ y >> │ │ >> │ v >> │ ┌─>XFS_DAS_ALLOC_NODE >> │ │ │ >> │ │ v >> │ └──y── need to alloc >> │ more blocks? >> │ │ >> │ n >> │ │ >> │ v >> │ was this >> └────────> a rename? ──n─┐ >> │ │ >> y │ >> │ │ >> v │ >> flip incomplete │ >> flag │ >> │ │ >> v │ >> ┌─>XFS_DAS_FLIP_NFLAG │ >> │ │ │ >> │ v │ >> │ remove │ >> │ old name │ >> │ │ │ >> │ v │ >> └────y── more to │ >> remove │ >> │ │ >> n │ >> │ │ >> v │ >> done <──────┘ >> >> Signed-off-by: Allison Collins >> --- >> fs/xfs/libxfs/xfs_attr.c | 368 ++++++++++++++++++++++++++-------------- >> fs/xfs/libxfs/xfs_attr.h | 1 + >> fs/xfs/libxfs/xfs_attr_remote.c | 67 +++++++- >> fs/xfs/libxfs/xfs_attr_remote.h | 4 + >> fs/xfs/libxfs/xfs_da_btree.h | 13 ++ >> 5 files changed, 319 insertions(+), 134 deletions(-) >> >> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c >> index cd3a3f7..4b788f2 100644 >> --- a/fs/xfs/libxfs/xfs_attr.c >> +++ b/fs/xfs/libxfs/xfs_attr.c >> @@ -58,6 +58,7 @@ STATIC int xfs_attr_node_hasname(xfs_da_args_t *args, >> struct xfs_da_state **state); >> STATIC int xfs_attr_fillstate(xfs_da_state_t *state); >> STATIC int xfs_attr_refillstate(xfs_da_state_t *state); >> +STATIC int xfs_attr_leaf_try_add(struct xfs_da_args *args, struct xfs_buf *bp); >> >> >> STATIC int >> @@ -259,9 +260,86 @@ int >> xfs_attr_set_args( >> struct xfs_da_args *args) >> { >> + int error = 0; >> + int err2 = 0; >> + struct xfs_buf *leaf_bp = NULL; >> + >> + do { >> + error = xfs_attr_set_iter(args, &leaf_bp); >> + if (error && error != -EAGAIN) >> + goto out; >> + >> + if (args->dac.flags & XFS_DAC_FINISH_TRANS) { >> + args->dac.flags &= ~XFS_DAC_FINISH_TRANS; >> + >> + err2 = xfs_defer_finish(&args->trans); >> + if (err2) { >> + error = err2; >> + goto out; >> + } >> + } >> + >> + err2 = xfs_trans_roll_inode(&args->trans, args->dp); >> + if (err2) { >> + error = err2; >> + goto out; >> + } >> + >> + if (leaf_bp) { >> + xfs_trans_bjoin(args->trans, leaf_bp); >> + xfs_trans_bhold(args->trans, leaf_bp); >> + } >> + >> + } while (error == -EAGAIN); >> + >> +out: >> + return error; >> +} >> + >> +/* >> + * Set the attribute specified in @args. >> + * This routine is meant to function as a delayed operation, and may return >> + * -EAGAIN when the transaction needs to be rolled. Calling functions will need >> + * to handle this, and recall the function until a successful error code is >> + * returned. >> + */ >> +int >> +xfs_attr_set_iter( >> + struct xfs_da_args *args, >> + struct xfs_buf **leaf_bp) >> +{ >> struct xfs_inode *dp = args->dp; >> - struct xfs_buf *leaf_bp = NULL; >> - int error, error2 = 0; >> + int error = 0; >> + int sf_size; >> + >> + /* State machine switch */ >> + switch (args->dac.dela_state) { >> + case XFS_DAS_ADD_LEAF: >> + goto add_leaf; >> + case XFS_DAS_ALLOC_LEAF: >> + case XFS_DAS_FLIP_LFLAG: >> + case XFS_DAS_FOUND_LBLK: >> + goto leaf; >> + case XFS_DAS_FOUND_NBLK: >> + case XFS_DAS_FLIP_NFLAG: >> + case XFS_DAS_ALLOC_NODE: >> + case XFS_DAS_LEAF_TO_NODE: >> + goto node; >> + default: >> + break; >> + } >> + >> + /* >> + * New inodes may not have an attribute fork yet. So set the attribute >> + * fork appropriately >> + */ >> + if (XFS_IFORK_Q((args->dp)) == 0) { >> + sf_size = sizeof(struct xfs_attr_sf_hdr) + >> + XFS_ATTR_SF_ENTSIZE_BYNAME(args->name.len, args->valuelen); >> + xfs_bmap_set_attrforkoff(args->dp, sf_size, NULL); >> + args->dp->i_afp = kmem_zone_zalloc(xfs_ifork_zone, 0); >> + args->dp->i_afp->if_flags = XFS_IFEXTENTS; >> + } >> >> /* >> * If the attribute list is non-existent or a shortform list, >> @@ -275,17 +353,16 @@ xfs_attr_set_args( >> * Try to add the attr to the attribute list in the inode. >> */ >> error = xfs_attr_try_sf_addname(dp, args); >> - if (error != -ENOSPC) { >> - error2 = xfs_trans_commit(args->trans); >> - args->trans = NULL; >> - return error ? error : error2; >> - } >> + >> + /* Should only be 0, -EEXIST or ENOSPC */ >> + if (error != -ENOSPC) >> + return error; >> >> /* >> * It won't fit in the shortform, transform to a leaf block. >> * GROT: another possible req'mt for a double-split btree op. >> */ >> - error = xfs_attr_shortform_to_leaf(args, &leaf_bp); >> + error = xfs_attr_shortform_to_leaf(args, leaf_bp); >> if (error) >> return error; >> >> @@ -293,41 +370,48 @@ xfs_attr_set_args( >> * Prevent the leaf buffer from being unlocked so that a >> * concurrent AIL push cannot grab the half-baked leaf >> * buffer and run into problems with the write verifier. >> - * Once we're done rolling the transaction we can release >> - * the hold and add the attr to the leaf. >> */ >> - xfs_trans_bhold(args->trans, leaf_bp); >> - error = xfs_defer_finish(&args->trans); >> - xfs_trans_bhold_release(args->trans, leaf_bp); >> - if (error) { >> - xfs_trans_brelse(args->trans, leaf_bp); >> - return error; >> - } >> + xfs_trans_bhold(args->trans, *leaf_bp); >> + args->dac.flags |= XFS_DAC_FINISH_TRANS; >> + args->dac.dela_state = XFS_DAS_ADD_LEAF; >> + return -EAGAIN; >> } >> >> - if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) { >> - error = xfs_attr_leaf_addname(args); >> - if (error != -ENOSPC) >> - return error; >> +add_leaf: >> >> - /* >> - * Commit that transaction so that the node_addname() >> - * call can manage its own transactions. >> - */ >> - error = xfs_defer_finish(&args->trans); >> - if (error) >> - return error; >> + /* >> + * After a shortform to leaf conversion, we need to hold the leaf and >> + * cylce out the transaction. When we get back, we need to release >> + * the leaf. >> + */ >> + if (*leaf_bp != NULL) { >> + xfs_trans_brelse(args->trans, *leaf_bp); >> + *leaf_bp = NULL; >> + } >> >> - /* >> - * Commit the current trans (including the inode) and >> - * start a new one. >> - */ >> - error = xfs_trans_roll_inode(&args->trans, dp); >> - if (error) >> + if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) { >> + error = xfs_attr_leaf_try_add(args, *leaf_bp); >> + switch (error) { >> + case -ENOSPC: >> + args->dac.flags |= XFS_DAC_FINISH_TRANS; >> + args->dac.dela_state = XFS_DAS_LEAF_TO_NODE; >> + return -EAGAIN; >> + case 0: >> + args->dac.dela_state = XFS_DAS_FOUND_LBLK; >> + return -EAGAIN; >> + default: >> return error; >> - >> + } >> +leaf: >> + error = xfs_attr_leaf_addname(args); >> + if (error == -ENOSPC) { >> + args->dac.dela_state = XFS_DAS_LEAF_TO_NODE; >> + return -EAGAIN; >> + } >> + return error; >> } >> - >> + args->dac.dela_state = XFS_DAS_LEAF_TO_NODE; >> +node: >> error = xfs_attr_node_addname(args); >> return error; >> } >> @@ -766,28 +850,29 @@ xfs_attr_leaf_try_add( >> * >> * This leaf block cannot have a "remote" value, we only call this routine >> * if bmap_one_block() says there is only one block (ie: no remote blks). >> + * >> + * This routine is meant to function as a delayed operation, and may return >> + * -EAGAIN when the transaction needs to be rolled. Calling functions will need >> + * to handle this, and recall the function until a successful error code is >> + * returned. >> */ >> STATIC int >> xfs_attr_leaf_addname( >> struct xfs_da_args *args) >> { >> - int error, forkoff; >> struct xfs_buf *bp = NULL; >> + int error, forkoff; >> struct xfs_inode *dp = args->dp; >> >> - trace_xfs_attr_leaf_addname(args); >> - >> - error = xfs_attr_leaf_try_add(args, bp); >> - if (error) >> - return error; >> - >> - /* >> - * Commit the transaction that added the attr name so that >> - * later routines can manage their own transactions. >> - */ >> - error = xfs_trans_roll_inode(&args->trans, dp); >> - if (error) >> - return error; >> + /* State machine switch */ >> + switch (args->dac.dela_state) { >> + case XFS_DAS_FLIP_LFLAG: >> + goto flip_flag; >> + case XFS_DAS_ALLOC_LEAF: >> + goto alloc_leaf; >> + default: >> + break; >> + } >> >> /* >> * If there was an out-of-line value, allocate the blocks we >> @@ -796,7 +881,28 @@ xfs_attr_leaf_addname( >> * maximum size of a transaction and/or hit a deadlock. >> */ >> if (args->rmtblkno > 0) { >> - error = xfs_attr_rmtval_set(args); >> + >> + /* Open coded xfs_attr_rmtval_set without trans handling */ >> + error = xfs_attr_rmtval_set_init(args); >> + if (error) >> + return error; >> + >> + /* >> + * Roll through the "value", allocating blocks on disk as >> + * required. >> + */ >> +alloc_leaf: >> + while (args->dac.blkcnt > 0) { >> + error = xfs_attr_rmtval_set_blk(args); >> + if (error) >> + return error; >> + >> + args->dac.flags |= XFS_DAC_FINISH_TRANS; >> + args->dac.dela_state = XFS_DAS_ALLOC_LEAF; >> + return -EAGAIN; >> + } >> + >> + error = xfs_attr_rmtval_set_value(args); >> if (error) >> return error; >> } >> @@ -815,13 +921,6 @@ xfs_attr_leaf_addname( >> error = xfs_attr3_leaf_flipflags(args); >> if (error) >> return error; >> - /* >> - * Commit the flag value change and start the next trans in >> - * series. >> - */ >> - error = xfs_trans_roll_inode(&args->trans, args->dp); >> - if (error) >> - return error; >> >> /* >> * Dismantle the "old" attribute/value pair by removing >> @@ -832,8 +931,17 @@ xfs_attr_leaf_addname( >> args->rmtblkno = args->rmtblkno2; >> args->rmtblkcnt = args->rmtblkcnt2; >> args->rmtvaluelen = args->rmtvaluelen2; >> + >> + args->dac.dela_state = XFS_DAS_FLIP_LFLAG; >> + return -EAGAIN; >> +flip_flag: >> if (args->rmtblkno) { >> - error = xfs_attr_rmtval_remove(args); >> + error = xfs_attr_rmtval_unmap(args); >> + >> + /* >> + * if (error == -EAGAIN), we will repeat this until >> + * args->rmtblkno is zero >> + */ >> if (error) >> return error; >> } > Hi Allison, > > In the case where args->rmtblkno is non-zero, xfs_attr_rmtval_unmap() invokes > xfs_bunmapi() for unmapping the file block range starting at > args->rmtblkno. If xfs_bunmapi() frees a subset of the range of blocks, it > returns with 'done' set to 0 and in turn xfs_attr_rmtval_unmap() returns with > -EAGAIN error. This will cause xfs_attr_leaf_addname() to return -EAGAIN to > its caller i.e. xfs_attr_set_iter(). In turn xfs_attr_set_iter() returns back > to xfs_attr_set_args(). Here the loop is executed once again and hence > xfs_attr_set_iter() is invoked with args->dac.dela_state set to > XFS_DAS_FLIP_LFLAG. Hence xfs_attr_leaf_addname() is invoked once again with > args->dac.dela_state set to XFS_DAS_FLIP_LFLAG. Here xfs_attr_rmtval_unmap() > is invoked once again with an unmodified args->rmtblkno. > Hi Chandan! Thanks for the digging! I think what I'm missing here is the xfs_attr_rmtval_invalidate, and an extra state for the remove. Similar to how patch 13 handles xfs_attr_rmtval_unmap. Will update! Thank you! Allison