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=-9.9 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,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 559B9C4363D for ; Fri, 2 Oct 2020 10:39:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 11D7F206CD for ; Fri, 2 Oct 2020 10:39:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="P1FF9Je5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726181AbgJBKjp (ORCPT ); Fri, 2 Oct 2020 06:39:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:59324 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725993AbgJBKjp (ORCPT ); Fri, 2 Oct 2020 06:39:45 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1601635183; 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=JU8cecP5EBcaLsvpGH9pp7mjRBanLFXc5GwXdqfRNBk=; b=P1FF9Je50HEZnfYz3ToBuAvEzi9GTedME4trnaxZkvooFRNG6B+rSgi7auSCRIsumT0lfX 9+ZH1eW2wQzlCrcBddVPpBs0tXb9vT7/6EdpIOp5Ro2n2F2Uqm0LrJmJoHUFIA9dCTFkda OkORq+Dqq1D1dTMGMkzZoi8CleLtSH8= 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-464-4JEf6TFVPASmL80JCZ_pFQ-1; Fri, 02 Oct 2020 06:39:42 -0400 X-MC-Unique: 4JEf6TFVPASmL80JCZ_pFQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D03441084C85; Fri, 2 Oct 2020 10:39:40 +0000 (UTC) Received: from bfoster (ovpn-116-218.rdu2.redhat.com [10.10.116.218]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4666073683; Fri, 2 Oct 2020 10:39:40 +0000 (UTC) Date: Fri, 2 Oct 2020 06:39:38 -0400 From: Brian Foster To: "Darrick J. Wong" Cc: Christoph Hellwig , Dave Chinner , linux-xfs@vger.kernel.org, david@fromorbit.com Subject: Re: [PATCH v4.2 4/5] xfs: xfs_defer_capture should absorb remaining block reservation Message-ID: <20201002103938.GA193265@bfoster> References: <160140139198.830233.3093053332257853111.stgit@magnolia> <160140141814.830233.6669476190490393801.stgit@magnolia> <20201002042015.GT49547@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201002042015.GT49547@magnolia> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Thu, Oct 01, 2020 at 09:20:15PM -0700, Darrick J. Wong wrote: > From: Darrick J. Wong > > When xfs_defer_capture extracts the deferred ops and transaction state > from a transaction, it should record the remaining block reservations so > that when we continue the dfops chain, we can reserve the same number of > blocks to use. We capture the reservations for both data and realtime > volumes. > > This adds the requirement that every log intent item recovery function > must be careful to reserve enough blocks to handle both itself and all > defer ops that it can queue. On the other hand, this enables us to do > away with the handwaving block estimation nonsense that was going on in > xlog_finish_defer_ops. > > Signed-off-by: Darrick J. Wong > --- > v4.2: don't fiddle with transaction internals, and save the rt > reservation too > --- Reviewed-by: Brian Foster > fs/xfs/libxfs/xfs_defer.c | 4 ++++ > fs/xfs/libxfs/xfs_defer.h | 4 ++++ > fs/xfs/xfs_log_recover.c | 21 +++------------------ > 3 files changed, 11 insertions(+), 18 deletions(-) > > diff --git a/fs/xfs/libxfs/xfs_defer.c b/fs/xfs/libxfs/xfs_defer.c > index 85c371d29e8d..10aeae7353ab 100644 > --- a/fs/xfs/libxfs/xfs_defer.c > +++ b/fs/xfs/libxfs/xfs_defer.c > @@ -575,6 +575,10 @@ xfs_defer_ops_capture( > dfc->dfc_tpflags = tp->t_flags & XFS_TRANS_LOWMODE; > tp->t_flags &= ~XFS_TRANS_LOWMODE; > > + /* Capture the remaining block reservations along with the dfops. */ > + dfc->dfc_blkres = tp->t_blk_res - tp->t_blk_res_used; > + dfc->dfc_rtxres = tp->t_rtx_res - tp->t_rtx_res_used; > + > return dfc; > } > > diff --git a/fs/xfs/libxfs/xfs_defer.h b/fs/xfs/libxfs/xfs_defer.h > index 3af82ebc1249..5c0e59b69ffa 100644 > --- a/fs/xfs/libxfs/xfs_defer.h > +++ b/fs/xfs/libxfs/xfs_defer.h > @@ -75,6 +75,10 @@ struct xfs_defer_capture { > /* Deferred ops state saved from the transaction. */ > struct list_head dfc_dfops; > unsigned int dfc_tpflags; > + > + /* Block reservations for the data and rt devices. */ > + unsigned int dfc_blkres; > + unsigned int dfc_rtxres; > }; > > /* > diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c > index 7804906d145b..1be5208e2a2f 100644 > --- a/fs/xfs/xfs_log_recover.c > +++ b/fs/xfs/xfs_log_recover.c > @@ -2439,27 +2439,12 @@ xlog_finish_defer_ops( > { > struct xfs_defer_capture *dfc, *next; > struct xfs_trans *tp; > - int64_t freeblks; > - uint64_t resblks; > int error = 0; > > list_for_each_entry_safe(dfc, next, capture_list, dfc_list) { > - /* > - * We're finishing the defer_ops that accumulated as a result > - * of recovering unfinished intent items during log recovery. > - * We reserve an itruncate transaction because it is the > - * largest permanent transaction type. Since we're the only > - * user of the fs right now, take 93% (15/16) of the available > - * free blocks. Use weird math to avoid a 64-bit division. > - */ > - freeblks = percpu_counter_sum(&mp->m_fdblocks); > - if (freeblks <= 0) > - return -ENOSPC; > - > - resblks = min_t(uint64_t, UINT_MAX, freeblks); > - resblks = (resblks * 15) >> 4; > - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, resblks, > - 0, XFS_TRANS_RESERVE, &tp); > + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, > + dfc->dfc_blkres, dfc->dfc_rtxres, > + XFS_TRANS_RESERVE, &tp); > if (error) > return error; > >