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 35E2DC43331 for ; Sat, 9 Nov 2019 21:41:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DAC702075C for ; Sat, 9 Nov 2019 21:41:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="KbI0nv3T" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726496AbfKIVlI (ORCPT ); Sat, 9 Nov 2019 16:41:08 -0500 Received: from aserp2120.oracle.com ([141.146.126.78]:38070 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726470AbfKIVlI (ORCPT ); Sat, 9 Nov 2019 16:41:08 -0500 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id xA9Ld9pr106175 for ; Sat, 9 Nov 2019 21:41:06 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-2019-08-05; bh=3C5xnc2PwXhONwHYMbuTnGFSCiBob9HlTRlmdjo4coc=; b=KbI0nv3TKzH1xJy8EvBPffkL9erG8azbFFCd1MZyk8GQCcUIV/uHkivtZEn0d5AWl6Bo zf4aAXcsE+Zi1acI8HtXou8s0PetWrY2O9TKZz1hc040/CvMJdoAByz8uuZwF/HpbofO M4Okg3u2vbzR/8LY+59/mjSefsvbtWtVA5pYo1hgdDmG9UFuvVzNgZs+DQbXl1CS94QU 3LjZX5DuitIHUEnjBpgDaRM/yrIKZZ0nbN2wxGw6qd0homSl9MsyXvPYr16qEMuenv6W QS54YzAYwvf0n968ARyFRQFpdDCfrc7Vld3QTbDnAmbNB85jX6PSSd12nP30Ijqlukij HQ== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by aserp2120.oracle.com with ESMTP id 2w5ndpsvvt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Sat, 09 Nov 2019 21:41:06 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id xA9LcaT0004403 for ; Sat, 9 Nov 2019 21:41:05 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3020.oracle.com with ESMTP id 2w5mt4h31u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Sat, 09 Nov 2019 21:41:05 +0000 Received: from abhmp0008.oracle.com (abhmp0008.oracle.com [141.146.116.14]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id xA9Lf497002236 for ; Sat, 9 Nov 2019 21:41:04 GMT Received: from [192.168.1.9] (/67.1.205.161) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Sat, 09 Nov 2019 21:41:04 +0000 Subject: Re: [PATCH v4 08/17] xfs: Factor out xfs_attr_leaf_addname helper To: "Darrick J. Wong" Cc: linux-xfs@vger.kernel.org References: <20191107012801.22863-1-allison.henderson@oracle.com> <20191107012801.22863-9-allison.henderson@oracle.com> <20191108205748.GZ6219@magnolia> From: Allison Collins Message-ID: <1824cddb-1b0b-c3f0-8eaa-77305e399c2d@oracle.com> Date: Sat, 9 Nov 2019 14:41:03 -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: <20191108205748.GZ6219@magnolia> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9436 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1910280000 definitions=main-1911090220 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9436 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1910280000 definitions=main-1911090221 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On 11/8/19 1:57 PM, Darrick J. Wong wrote: > On Wed, Nov 06, 2019 at 06:27:52PM -0700, Allison Collins wrote: >> Factor out new helper function xfs_attr_leaf_try_add. >> Because new delayed attribute routines cannot roll >> transactions, we carve off the parts of >> xfs_attr_leaf_addname that we can use. This will help >> to reduce repetitive code later when we introduce >> delayed attributes. >> >> Signed-off-by: Allison Collins >> --- >> fs/xfs/libxfs/xfs_attr.c | 84 +++++++++++++++++++++++++++++------------------- >> 1 file changed, 51 insertions(+), 33 deletions(-) >> >> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c >> index 212995f..dda2eba 100644 >> --- a/fs/xfs/libxfs/xfs_attr.c >> +++ b/fs/xfs/libxfs/xfs_attr.c >> @@ -305,10 +305,33 @@ xfs_attr_set_args( >> } >> } >> >> - if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) >> + if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) { >> error = xfs_attr_leaf_addname(args); >> - else >> + if (error == -ENOSPC) { >> + /* >> + * Commit that transaction so that the node_addname() >> + * call can manage its own transactions. >> + */ >> + error = xfs_defer_finish(&args->trans); >> + if (error) >> + return error; >> + >> + /* >> + * Commit the current trans (including the inode) and >> + * start a new one. >> + */ >> + error = xfs_trans_roll_inode(&args->trans, dp); >> + if (error) >> + return error; >> + >> + /* >> + * Fob the rest of the problem off on the Btree code. >> + */ >> + error = xfs_attr_node_addname(args); >> + } >> + } else { >> error = xfs_attr_node_addname(args); >> + } >> return error; > > >> } >> >> @@ -601,21 +624,12 @@ xfs_attr_shortform_addname(xfs_da_args_t *args) >> * External routines when attribute list is one block >> *========================================================================*/ >> >> -/* >> - * Add a name to the leaf attribute list structure >> - * >> - * 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). >> - */ >> STATIC int >> -xfs_attr_leaf_addname( >> - struct xfs_da_args *args) >> +xfs_attr_leaf_try_add( > > (total stream of consciousness here...) > > AFAICT the old _addname function's responsibilities were: > > 1 Try to add a new attr key entry to the leaf block, with INCOMPLETE set > if it's a rename op or we need to set a remote value. > 2 If there wasn't space in the leaf block, convert to node format, call > the node version of this function, and exit. > 3 Allocating blocks for the remote attr value and writing them, if > applicable > 4 If it's a rename operation, clearing the INCOMPLETE flag on the new > entry; setting it on the old entry; and then removing the old entry. > 5 Clearing the INCOMPLETE flag on the new entry when we're done writing > a remote value (if applicable) > > I think we arrive at this split so that we don't have a transaction roll > in the middle of the function, right? And also to make the "convert to > node format and roll" bits go elsewhere? > > The way I'm thinking about how to accomplish this is... > > xfs_attr_leaf_addname should be renamed xfs_attr_leaf_setname, and then > hoist (1) into a separate function, move (2) into xfs_attr_set_args, and > hoist (4) into a separate function. > > ...ok, so let's test how closely my understanding fits the changes made > in this patch: > > _try_add is basically (1). > > Most of (2) happened, though the call to xfs_attr3_leaf_to_node ought to > go into the caller so that the conversion stays with the defer_finish > and roll. > > (4) could still be done, maybe as a separate prep patch. > I think you're on the right track. Perhaps the diff made it look a little crazier than it seems. Maybe its easier to describe it as this: I renamed xfs_attr_leaf_addname to xfs_attr_leaf_try_add, and then deleted (2) out of the body of the function. The upper half (1) became the helper function, and lower half (3, 4, and 5) became the new xfs_attr_leaf_addname, which now calls the helper at the start of the routine. Finally (2) got factored up into the caller. Hope that helps some :-) The point of all this being to jigsaw out (1) into a stand alone routine that we can use later in delayed attrs. > Hm, ok, I think I understand what this patch does. The call site in > xfs_attr_set_args would be clearer (and less indenty) if it looked like: > > if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) { > error = xfs_attr_leaf_addname(args); > if (error == 0 || error != -ENOSPC) > return error; > > /* Promote the attribute list to node format. */ > error = xfs_attr3_leaf_to_node(args); > if (error) > return error; I think this part here is already taken care of in xfs_attr_leaf_addname, but otherwise, I think the rest of this is equivalent. Will update in the next set. Thanks for the reviews! Allison > > /* > * Commit that transaction so that the node_addname() > * call can manage its own transactions. > */ > error = xfs_defer_finish(&args->trans); > if (error) > return error; > > /* > * Commit the current trans (including the inode) and > * start a new one. > */ > error = xfs_trans_roll_inode(&args->trans, dp); > if (error) > return error; > } > > return xfs_attr_node_addname(args); > > But otherwise it looks decent, assuming I understood any of it. :) > > --D > >> + struct xfs_da_args *args, >> + struct xfs_buf *bp) >> { >> - struct xfs_buf *bp; >> - int retval, error, forkoff; >> - struct xfs_inode *dp = args->dp; >> - >> - trace_xfs_attr_leaf_addname(args); >> + int retval, error; >> >> /* >> * Look up the given attribute in the leaf block. Figure out if >> @@ -661,31 +675,35 @@ xfs_attr_leaf_addname( >> retval = xfs_attr3_leaf_add(bp, args); >> if (retval == -ENOSPC) { >> /* >> - * Promote the attribute list to the Btree format, then >> - * Commit that transaction so that the node_addname() call >> - * can manage its own transactions. >> + * Promote the attribute list to the Btree format. >> + * Unless an error occurs, retain the -ENOSPC retval >> */ >> error = xfs_attr3_leaf_to_node(args); >> if (error) >> return error; >> - error = xfs_defer_finish(&args->trans); >> - if (error) >> - return error; >> + } >> + return retval; >> +} >> >> - /* >> - * Commit the current trans (including the inode) and start >> - * a new one. >> - */ >> - error = xfs_trans_roll_inode(&args->trans, dp); >> - if (error) >> - return error; >> >> - /* >> - * Fob the whole rest of the problem off on the Btree code. >> - */ >> - error = xfs_attr_node_addname(args); >> +/* >> + * Add a name to the leaf attribute list structure >> + * >> + * 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). >> + */ >> +STATIC int >> +xfs_attr_leaf_addname(struct xfs_da_args *args) >> +{ >> + int error, forkoff; >> + struct xfs_buf *bp = NULL; >> + 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 >> -- >> 2.7.4 >>