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=-11.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,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 3B1B4C388F7 for ; Fri, 13 Nov 2020 17:12:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D4F9622226 for ; Fri, 13 Nov 2020 17:12:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="yB9UT1c5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726057AbgKMRMC (ORCPT ); Fri, 13 Nov 2020 12:12:02 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:40672 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726003AbgKMRMB (ORCPT ); Fri, 13 Nov 2020 12:12:01 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 0ADH3ZSb124469; Fri, 13 Nov 2020 17:12:11 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=kbCEjs1duXiaeBj9rhIxHKZm+HbmA0j4LwzyJY0Du04=; b=yB9UT1c5uJEU3g6lXFCuJMt2lBJwPErth5NlPN4QgYWPfQGB7YpnplVBSQ3tw/+BF801 uUyWIQcJ7PjXUXPk51JC3zCL2wOvWdskn4g9Mll0Hu+aYVMUGofXrkM3AMkkWPmD+VYB ddxFT51Me0xCT8cJ5yapJ/fTxJmMLoazzAqbb5ZOUvP2tP8Wtaewvi6FZobyU4NckWle lwpcUdu0BGr0++FdvkYsOI+7IDl362kVKa/unhIXswzpIBPuFoO+l22+nm2jYTsNJe3+ 5w7zctatz9JY3qXEctyKLeJ3OJpEJEH0m+InLw1s74NXIdwUELvklapcGMqU10iy/Y/c OQ== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by userp2120.oracle.com with ESMTP id 34p72f1jnn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 13 Nov 2020 17:12:11 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 0ADH5Eta150177; Fri, 13 Nov 2020 17:12:11 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3020.oracle.com with ESMTP id 34rt587b3x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 13 Nov 2020 17:12:11 +0000 Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 0ADHCAKK003779; Fri, 13 Nov 2020 17:12:10 GMT Received: from [192.168.1.223] (/67.1.244.254) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 13 Nov 2020 09:12:10 -0800 Subject: Re: [PATCH v13 03/10] xfs: Add delay ready attr set routines To: Chandan Babu R Cc: "Darrick J. Wong" , linux-xfs@vger.kernel.org References: <20201023063435.7510-1-allison.henderson@oracle.com> <20201110215702.GH9695@magnolia> <20322189.3UhRF6KiVz@garuda> From: Allison Henderson Message-ID: <0d6bd8a6-e43e-6344-5e79-3cf348f447d6@oracle.com> Date: Fri, 13 Nov 2020 10:12:09 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20322189.3UhRF6KiVz@garuda> 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=9804 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 bulkscore=0 mlxscore=0 mlxlogscore=999 suspectscore=0 adultscore=0 phishscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011130111 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9804 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 mlxlogscore=999 mlxscore=0 malwarescore=0 suspectscore=0 lowpriorityscore=0 adultscore=0 phishscore=0 priorityscore=1501 spamscore=0 impostorscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011130111 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On 11/13/20 2:16 AM, Chandan Babu R wrote: > On Friday 13 November 2020 7:03:13 AM IST Allison Henderson wrote: >> >> On 11/10/20 2:57 PM, Darrick J. Wong wrote: >>> On Tue, Oct 27, 2020 at 07:02:55PM +0530, Chandan Babu R wrote: >>>> On Friday 23 October 2020 12:04:28 PM IST Allison Henderson 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. See xfs_attr.h for a more detailed diagram of the states. >>>>> >>>>> 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. xfs_attr_set_args has >>>>> now become a simple loop to refresh the transaction until the operation >>>>> is completed. Lastly, xfs_attr_rmtval_remove is no longer used, and is >>>>> removed. >>>> >>>> One nit. xfs_attr_rmtval_remove()'s prototype declaration needs to be removed >>>> from xfs_attr_remote.h. >> Alrighty, will pull out >> >>>> >>>>> >>>>> Signed-off-by: Allison Henderson >>>>> --- >>>>> fs/xfs/libxfs/xfs_attr.c | 370 ++++++++++++++++++++++++++-------------- >>>>> fs/xfs/libxfs/xfs_attr.h | 126 +++++++++++++- >>>>> fs/xfs/libxfs/xfs_attr_remote.c | 99 +++++++---- >>>>> fs/xfs/libxfs/xfs_attr_remote.h | 4 + >>>>> fs/xfs/xfs_trace.h | 1 - >>>>> 5 files changed, 439 insertions(+), 161 deletions(-) >>>>> >>>>> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c >>>>> index 6ca94cb..95c98d7 100644 >>>>> --- a/fs/xfs/libxfs/xfs_attr.c >>>>> +++ b/fs/xfs/libxfs/xfs_attr.c >>>>> @@ -44,7 +44,7 @@ STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args); >>>>> * Internal routines when attribute list is one block. >>>>> */ >>>>> STATIC int xfs_attr_leaf_get(xfs_da_args_t *args); >>>>> -STATIC int xfs_attr_leaf_addname(xfs_da_args_t *args); >>>>> +STATIC int xfs_attr_leaf_addname(struct xfs_delattr_context *dac); >>>>> STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args); >>>>> STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp); >>>>> >>>>> @@ -52,12 +52,15 @@ STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp); >>>>> * Internal routines when attribute list is more than one block. >>>>> */ >>>>> STATIC int xfs_attr_node_get(xfs_da_args_t *args); >>>>> -STATIC int xfs_attr_node_addname(xfs_da_args_t *args); >>>>> +STATIC int xfs_attr_node_addname(struct xfs_delattr_context *dac); >>>>> STATIC int xfs_attr_node_removename_iter(struct xfs_delattr_context *dac); >>>>> 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 xfs_attr_set_iter(struct xfs_delattr_context *dac, >>>>> + struct xfs_buf **leaf_bp); >>>>> >>>>> int >>>>> xfs_inode_hasattr( >>>>> @@ -218,8 +221,11 @@ xfs_attr_is_shortform( >>>>> >>>>> /* >>>>> * Attempts to set an attr in shortform, or converts short form to leaf form if >>>>> - * there is not enough room. If the attr is set, the transaction is committed >>>>> - * and set to NULL. >>>>> + * there is not enough room. This function is meant to operate as a helper >>>>> + * routine to the delayed attribute functions. It returns -EAGAIN to indicate >>>>> + * that the calling function should roll the transaction, and then proceed to >>>>> + * add the attr in leaf form. This subroutine does not expect to be recalled >>>>> + * again like the other delayed attr routines do. >>>>> */ >>>>> STATIC int >>>>> xfs_attr_set_shortform( >>>>> @@ -227,16 +233,16 @@ xfs_attr_set_shortform( >>>>> struct xfs_buf **leaf_bp) >>>>> { >>>>> struct xfs_inode *dp = args->dp; >>>>> - int error, error2 = 0; >>>>> + int error = 0; >>>>> >>>>> /* >>>>> * Try to add the attr to the attribute list in the inode. >>>>> */ >>>>> error = xfs_attr_try_sf_addname(dp, args); >>>>> + >>>>> + /* Should only be 0, -EEXIST or ENOSPC */ >>>>> if (error != -ENOSPC) { >>>>> - error2 = xfs_trans_commit(args->trans); >>>>> - args->trans = NULL; >>>>> - return error ? error : error2; >>>>> + return error; >>>>> } >>>>> /* >>>>> * It won't fit in the shortform, transform to a leaf block. GROT: >>>>> @@ -249,18 +255,10 @@ xfs_attr_set_shortform( >>>>> /* >>>>> * 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. >>>>> + * with the write verifier. >>>>> */ >>>>> 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; >>>>> - } >>>>> - >>>>> - return 0; >>>>> + return -EAGAIN; >>>>> } >>>>> >>>>> /* >>>>> @@ -268,7 +266,7 @@ xfs_attr_set_shortform( >>>>> * also checks for a defer finish. Transaction is finished and rolled as >>>>> * needed, and returns true of false if the delayed operation should continue. >>>>> */ >>>>> -int >>>>> +STATIC int >>>>> xfs_attr_trans_roll( >>>>> struct xfs_delattr_context *dac) >>>>> { >>>>> @@ -297,61 +295,130 @@ int >>>>> xfs_attr_set_args( >>>>> struct xfs_da_args *args) >>>>> { >>>>> - struct xfs_inode *dp = args->dp; >>>>> - struct xfs_buf *leaf_bp = NULL; >>>>> - int error = 0; >>>>> + struct xfs_buf *leaf_bp = NULL; >>>>> + int error = 0; >>>>> + struct xfs_delattr_context dac = { >>>>> + .da_args = args, >>>>> + }; >>>>> + >>>>> + do { >>>>> + error = xfs_attr_set_iter(&dac, &leaf_bp); >>>>> + if (error != -EAGAIN) >>>>> + break; >>>>> + >>>>> + error = xfs_attr_trans_roll(&dac); >>>>> + if (error) >>>>> + return error; >>>>> + >>>>> + if (leaf_bp) { >>>>> + xfs_trans_bjoin(args->trans, leaf_bp); >>>>> + xfs_trans_bhold(args->trans, leaf_bp); >>>>> + } >>>> >>>> When xfs_attr_set_iter() causes a "short form" attribute list to be converted >>>> to "leaf form", leaf_bp would point to an xfs_buf which has been added to the >>>> transaction and also XFS_BLI_HOLD flag is set on the buffer (last statement in >>>> xfs_attr_set_shortform()). XFS_BLI_HOLD flag makes sure that the new >>>> transaction allocated by xfs_attr_trans_roll() would continue to have leaf_bp >>>> in the transaction's item list. Hence I think the above calls to >>>> xfs_trans_bjoin() and xfs_trans_bhold() are not required. >> Sorry, I just noticed Chandans commentary for this patch. Apologies. I >> think we can get away with out this now, but yes this routine disappears >> at the end of the set now. Will clean out anyway for bisecting reasons >> though. :-) > > No problem. As an aside, I stopped reviewing the patchset after I noticed > Brian's review comments for "[PATCH v13 02/10] xfs: Add delay ready attr > remove routines" suggesting some more code refactoring work. > No worries, thats reasonable. It's why I only send this out in subsets to try and keep people sort of focused on a smaller area because stuff at the end of the set changes more often as a result of things moving around at the bottom of the set. It doesn't make sense to channel too much effort into something that's still moving around so much :-) Allison >> >>> >>> I /think/ the defer ops will rejoin the buffer each time it rolls, which >>> means that xfs_attr_trans_roll returns with the buffer already joined to >>> the transaction? And I think you're right that the bhold isn't needed, >>> because holding is dictated by the lower levels (i.e. _set_iter). >>> >>>> Please let me know if I am missing something obvious here. >>> >>> The entire function goes away by the end of the series. :) >>> >>> --D >>> >>>> >>>> >>>> >>>> >> > >