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 52987C7CFC6 for ; Fri, 13 Dec 2019 20:39:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7952B246B3 for ; Fri, 13 Dec 2019 20:39:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Sjw+Tdo9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728453AbfLMRax (ORCPT ); Fri, 13 Dec 2019 12:30:53 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:25106 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728445AbfLMRax (ORCPT ); Fri, 13 Dec 2019 12:30:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576258251; 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: in-reply-to:in-reply-to:references:references; bh=NjJHnFCWa7FCL2EYzc8iQh2uP01n1szCdgzdQgYzmDc=; b=Sjw+Tdo93EPUaCc/Z9XWRi9vb8tiHhql4iEz/0qg1yNKi899HuNxxOeeVWLbeKqQZzeYBr o2+M3PUY/OU+YiXWrzFZSvPejTwbohoYuFf6+u1V/CSZGDS87/NJQJ82nP7OgotLO7zPQU wXjw61gkjL98fU0/y+yULPdqQGTvQxE= 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-353-ydbL3nENMviE3yhlccby7Q-1; Fri, 13 Dec 2019 12:30:48 -0500 X-MC-Unique: ydbL3nENMviE3yhlccby7Q-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7A4DE107ACFA; Fri, 13 Dec 2019 17:30:47 +0000 (UTC) Received: from bfoster (dhcp-41-2.bos.redhat.com [10.18.41.2]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1099760C88; Fri, 13 Dec 2019 17:30:46 +0000 (UTC) Date: Fri, 13 Dec 2019 12:30:46 -0500 From: Brian Foster To: Allison Collins Cc: linux-xfs@vger.kernel.org Subject: Re: [PATCH v5 13/14] xfs: Add delay ready attr remove routines Message-ID: <20191213173046.GG43376@bfoster> References: <20191212041513.13855-1-allison.henderson@oracle.com> <20191212041513.13855-14-allison.henderson@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191212041513.13855-14-allison.henderson@oracle.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Wed, Dec 11, 2019 at 09:15:12PM -0700, Allison Collins wrote: > This patch modifies the attr remove 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_remove_args has become > xfs_attr_remove_iter, which uses a sort of state machine like switch > to keep track of where it was when EAGAIN was returned. > xfs_attr_node_removename has also been modified to use the switch, > and a new version of xfs_attr_remove_args consists of a simple loop > to refresh the transaction until the operation is completed. > > This patch also adds a new struct xfs_delattr_context, which we will > use to keep track of the current state of an attribute operation. > The new xfs_delattr_state enum is used to track various operations > that are in progress so that we know not to repeat them, and resume > where we left off before EAGAIN was returned to cycle out the > transaction. Other members take the place of local variables that > need to retain their values across multiple function recalls. > > Signed-off-by: Allison Collins > --- > fs/xfs/libxfs/xfs_attr.c | 127 ++++++++++++++++++++++++++++++++++++------- > fs/xfs/libxfs/xfs_attr.h | 1 + > fs/xfs/libxfs/xfs_da_btree.h | 16 ++++++ > fs/xfs/scrub/common.c | 2 + > fs/xfs/xfs_acl.c | 2 + > fs/xfs/xfs_attr_list.c | 1 + > fs/xfs/xfs_ioctl.c | 2 + > fs/xfs/xfs_ioctl32.c | 2 + > fs/xfs/xfs_iops.c | 2 + > fs/xfs/xfs_xattr.c | 1 + > 10 files changed, 137 insertions(+), 19 deletions(-) > > diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c > index b5a5c84..726b75e 100644 > --- a/fs/xfs/libxfs/xfs_attr.c > +++ b/fs/xfs/libxfs/xfs_attr.c ... > @@ -1206,12 +1249,29 @@ xfs_attr_node_removename( > struct xfs_buf *bp; > int retval, error, forkoff; > struct xfs_inode *dp = args->dp; > + int done = 0; > > trace_xfs_attr_node_removename(args); > + state = args->dac.da_state; > + blk = args->dac.blk; > + > + /* State machine switch */ > + switch (args->dac.dela_state) { > + case XFS_DAS_RM_NODE_BLKS: > + goto rm_node_blks; > + case XFS_DAS_RM_INVALIDATE: > + goto rm_invalidate; > + case XFS_DAS_RM_SHRINK: > + goto rm_shrink; > + default: > + break; > + } I think this function could use at least a couple more prepatory refactoring patches before we introduce the state machine... > > error = xfs_attr_node_hasname(args, &state); > if (error != -EEXIST) > goto out; > + else > + error = 0; > > /* > * If there is an out-of-line value, de-allocate the blocks. > @@ -1221,6 +1281,14 @@ xfs_attr_node_removename( > blk = &state->path.blk[ state->path.active-1 ]; > ASSERT(blk->bp != NULL); > ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC); > + > + /* > + * Store blk and state in the context incase we need to cycle out the > + * transaction > + */ > + args->dac.blk = blk; > + args->dac.da_state = state; > + > if (args->rmtblkno > 0) { > /* > * Fill in disk block numbers in the state structure > @@ -1239,13 +1307,40 @@ xfs_attr_node_removename( > if (error) > goto out; > > - error = xfs_trans_roll_inode(&args->trans, args->dp); > - if (error) > - goto out; > + args->dac.dela_state = XFS_DAS_RM_INVALIDATE; > + return -EAGAIN; > + } The entire (args->rmtblkno > 0) branch above could be reduced into a helper function. BTW, does it matter whether the invalidate occurs before or after this particular transaction roll? It looks to me it just makes in-core changes. I'm wondering if we could just fold that in as well and eliminate that state entirely. > + > +rm_invalidate: > + args->dac.dela_state = XFS_DAS_RM_INVALIDATE; > > - error = xfs_attr_rmtval_remove(args); > + if (args->rmtblkno > 0) { > + error = xfs_attr_rmtval_invalidate(args); > if (error) > goto out; > + } > + > +rm_node_blks: > + > + args->dac.dela_state = XFS_DAS_RM_NODE_BLKS; > + if (args->rmtblkno > 0) { > + /* > + * Unmap value blocks for this attr. This is similar to > + * xfs_attr_rmtval_remove, but open coded here to return EAGAIN > + * for new transactions > + */ > + while (!done && !error) { > + error = xfs_bunmapi(args->trans, args->dp, > + args->rmtblkno, args->rmtblkcnt, > + XFS_BMAPI_ATTRFORK, 1, &done); > + if (error) > + return error; > + > + if (!done) { > + args->dac.dela_state = XFS_DAS_RM_NODE_BLKS; > + return -EAGAIN; > + } > + } > The above could use the helper function treatment as well. E.g., something like xfs_attr_rmtval_unmap() that has a *done param this function can check to determine whether to return -EAGAIN or proceed. > /* > * Refill the state structure with buffers, the prior calls > @@ -1271,17 +1366,14 @@ xfs_attr_node_removename( > error = xfs_da3_join(state); > if (error) > goto out; > - error = xfs_defer_finish(&args->trans); > - if (error) > - goto out; Hmm.. I think we might want to lift the xfs_defer_finish() call up into the iter() function rather than just drop it. Otherwise this changes behavior in that the transaction roll doesn't complete pending deferred operations. > - /* > - * Commit the Btree join operation and start a new trans. > - */ > - error = xfs_trans_roll_inode(&args->trans, dp); > - if (error) > - goto out; > + > + args->dac.dela_state = XFS_DAS_RM_SHRINK; > + return -EAGAIN; > } > > +rm_shrink: > + args->dac.dela_state = XFS_DAS_RM_SHRINK; > + > /* > * If the result is small enough, push it all into the inode. > */ > @@ -1302,9 +1394,6 @@ xfs_attr_node_removename( > /* bp is gone due to xfs_da_shrink_inode */ > if (error) > goto out; > - error = xfs_defer_finish(&args->trans); > - if (error) > - goto out; > } else > xfs_trans_brelse(args->trans, bp); > } Same deal here (and same fundamental comment for the next patch).. create a xfs_attr_node_shrink() or some such helper to make functions that handle state smaller and easier to follow once the state bits are introduced. Brian > diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h > index 3b5dad4..f6ac571 100644 > --- a/fs/xfs/libxfs/xfs_attr.h > +++ b/fs/xfs/libxfs/xfs_attr.h > @@ -152,6 +152,7 @@ int xfs_attr_set_args(struct xfs_da_args *args); > int xfs_attr_remove(struct xfs_inode *dp, struct xfs_name *name, int flags); > int xfs_has_attr(struct xfs_da_args *args); > int xfs_attr_remove_args(struct xfs_da_args *args); > +int xfs_attr_remove_iter(struct xfs_da_args *args); > int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize, > int flags, struct attrlist_cursor_kern *cursor); > bool xfs_attr_namecheck(const void *name, size_t length); > diff --git a/fs/xfs/libxfs/xfs_da_btree.h b/fs/xfs/libxfs/xfs_da_btree.h > index 580fb72..137ec29 100644 > --- a/fs/xfs/libxfs/xfs_da_btree.h > +++ b/fs/xfs/libxfs/xfs_da_btree.h > @@ -49,10 +49,26 @@ enum xfs_dacmp { > XFS_CMP_CASE /* names are same but differ in case */ > }; > > +enum xfs_delattr_state { > + XFS_DAS_RM_INVALIDATE = 1, /* We are invalidating blocks */ > + XFS_DAS_RM_SHRINK = 2, /* We are shrinking the tree */ > + XFS_DAS_RM_NODE_BLKS = 3,/* We are removing node blocks */ > +}; > + > +/* > + * Context used for keeping track of delayed attribute operations > + */ > +struct xfs_delattr_context { > + struct xfs_da_state *da_state; > + struct xfs_da_state_blk *blk; > + enum xfs_delattr_state dela_state; > +}; > + > /* > * Structure to ease passing around component names. > */ > typedef struct xfs_da_args { > + struct xfs_delattr_context dac;/* context used for delay attr ops */ > struct xfs_da_geometry *geo; /* da block geometry */ > struct xfs_name name; /* name, length and argument flags*/ > uint8_t filetype; /* filetype of inode for directories */ > diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c > index 1887605..9a649d1 100644 > --- a/fs/xfs/scrub/common.c > +++ b/fs/xfs/scrub/common.c > @@ -24,6 +24,8 @@ > #include "xfs_rmap_btree.h" > #include "xfs_log.h" > #include "xfs_trans_priv.h" > +#include "xfs_da_format.h" > +#include "xfs_da_btree.h" > #include "xfs_attr.h" > #include "xfs_reflink.h" > #include "scrub/scrub.h" > diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c > index 7b0e5b7..573e47e 100644 > --- a/fs/xfs/xfs_acl.c > +++ b/fs/xfs/xfs_acl.c > @@ -10,6 +10,8 @@ > #include "xfs_trans_resv.h" > #include "xfs_mount.h" > #include "xfs_inode.h" > +#include "xfs_da_format.h" > +#include "xfs_da_btree.h" > #include "xfs_attr.h" > #include "xfs_trace.h" > #include "xfs_error.h" > diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c > index d37743b..881b9a4 100644 > --- a/fs/xfs/xfs_attr_list.c > +++ b/fs/xfs/xfs_attr_list.c > @@ -12,6 +12,7 @@ > #include "xfs_trans_resv.h" > #include "xfs_mount.h" > #include "xfs_da_format.h" > +#include "xfs_da_btree.h" > #include "xfs_inode.h" > #include "xfs_trans.h" > #include "xfs_bmap.h" > diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c > index 4fc8698..a31753f 100644 > --- a/fs/xfs/xfs_ioctl.c > +++ b/fs/xfs/xfs_ioctl.c > @@ -15,6 +15,8 @@ > #include "xfs_iwalk.h" > #include "xfs_itable.h" > #include "xfs_error.h" > +#include "xfs_da_format.h" > +#include "xfs_da_btree.h" > #include "xfs_attr.h" > #include "xfs_bmap.h" > #include "xfs_bmap_util.h" > diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c > index c4c4f09..4b693e3 100644 > --- a/fs/xfs/xfs_ioctl32.c > +++ b/fs/xfs/xfs_ioctl32.c > @@ -17,6 +17,8 @@ > #include "xfs_itable.h" > #include "xfs_fsops.h" > #include "xfs_rtalloc.h" > +#include "xfs_da_format.h" > +#include "xfs_da_btree.h" > #include "xfs_attr.h" > #include "xfs_ioctl.h" > #include "xfs_ioctl32.h" > diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c > index e85bbf5..a2d299f 100644 > --- a/fs/xfs/xfs_iops.c > +++ b/fs/xfs/xfs_iops.c > @@ -13,6 +13,8 @@ > #include "xfs_inode.h" > #include "xfs_acl.h" > #include "xfs_quota.h" > +#include "xfs_da_format.h" > +#include "xfs_da_btree.h" > #include "xfs_attr.h" > #include "xfs_trans.h" > #include "xfs_trace.h" > diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c > index 5623682..8bdb972 100644 > --- a/fs/xfs/xfs_xattr.c > +++ b/fs/xfs/xfs_xattr.c > @@ -10,6 +10,7 @@ > #include "xfs_log_format.h" > #include "xfs_da_format.h" > #include "xfs_inode.h" > +#include "xfs_da_btree.h" > #include "xfs_attr.h" > #include "xfs_acl.h" > > -- > 2.7.4 >