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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 31004C2D0CE for ; Fri, 24 Jan 2020 23:12:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F10CA2077C for ; Fri, 24 Jan 2020 23:12:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="bX+GWYr1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387420AbgAXXMI (ORCPT ); Fri, 24 Jan 2020 18:12:08 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:43256 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387419AbgAXXMI (ORCPT ); Fri, 24 Jan 2020 18:12:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ARUoVKp0kXpcgthiwM1Es0rUc8wtQMG96kOEIR72aOs=; b=bX+GWYr1iugpivTV5MxU9trhp fgfOIlRZRiKHbh0vT8Svob7Sz8YzYm3YvyIFv0m7MwimwXv5cx9HcIdQiCrjeYz+9WVP+X8BxXgtk UHB8fktn0b/0xyiPIRO/iwNY+ppoXvjjEbFEGSQhjjLBt1sFBiOQ7FvDUlWpTcNm/+iGoQiKrcJjV IluIQSxiKXAN8ZNH6Jph+wlCs2acRX6dihFLeVMji4Og//32l905YLfWFluVpiQUhFlolC9f09exj Zghl1TxcqGFqClmPlRi5SV5UhM+suSVVqGXcrM9hSu4bIqxy9nZNEvG4Li19wpDkgim6c7vdRzWn1 R+CZ1nm0w==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1iv87T-0005ah-G7; Fri, 24 Jan 2020 23:12:07 +0000 Date: Fri, 24 Jan 2020 15:12:07 -0800 From: Christoph Hellwig To: "Darrick J. Wong" Cc: linux-xfs@vger.kernel.org, hch@infradead.org, david@fromorbit.com Subject: Re: [PATCH 10/12] xfs: make xfs_*read_agf return EAGAIN to ALLOC_FLAG_TRYLOCK callers Message-ID: <20200124231207.GD20014@infradead.org> References: <157984313582.3139258.1136501362141645797.stgit@magnolia> <157984320125.3139258.966527323692871610.stgit@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <157984320125.3139258.966527323692871610.stgit@magnolia> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Thu, Jan 23, 2020 at 09:20:01PM -0800, Darrick J. Wong wrote: > From: Darrick J. Wong > > Refactor xfs_read_agf and xfs_alloc_read_agf to return EAGAIN if the > caller passed TRYLOCK and we weren't able to get the lock; and change > the callers to recognize this. > > Signed-off-by: Darrick J. Wong > --- > fs/xfs/libxfs/xfs_alloc.c | 36 ++++++++++++++---------------------- > fs/xfs/libxfs/xfs_bmap.c | 11 ++++++----- > fs/xfs/xfs_filestream.c | 11 +++++------ > 3 files changed, 25 insertions(+), 33 deletions(-) > > > diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c > index 34b65635ee34..d8053bc96c4d 100644 > --- a/fs/xfs/libxfs/xfs_alloc.c > +++ b/fs/xfs/libxfs/xfs_alloc.c > @@ -2502,12 +2502,11 @@ xfs_alloc_fix_freelist( > > if (!pag->pagf_init) { > error = xfs_alloc_read_agf(mp, tp, args->agno, flags, &agbp); > - if (error) > + if (error) { > + /* Couldn't lock the AGF so skip this AG. */ > + if (error == -EAGAIN) > + error = 0; > goto out_no_agbp; > - if (!pag->pagf_init) { > - ASSERT(flags & XFS_ALLOC_FLAG_TRYLOCK); > - ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING)); > - goto out_agbp_relse; > } > } > > @@ -2533,11 +2532,10 @@ xfs_alloc_fix_freelist( > */ > if (!agbp) { > error = xfs_alloc_read_agf(mp, tp, args->agno, flags, &agbp); > - if (error) > - goto out_no_agbp; > - if (!agbp) { > - ASSERT(flags & XFS_ALLOC_FLAG_TRYLOCK); > - ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING)); > + if (error) { > + /* Couldn't lock the AGF so skip this AG. */ > + if (error == -EAGAIN) > + error = 0; > goto out_no_agbp; > } > } > @@ -2768,11 +2766,10 @@ xfs_alloc_pagf_init( > xfs_buf_t *bp; > int error; > > - if ((error = xfs_alloc_read_agf(mp, tp, agno, flags, &bp))) > - return error; > - if (bp) > + error = xfs_alloc_read_agf(mp, tp, agno, flags, &bp); > + if (!error) > xfs_trans_brelse(tp, bp); > - return 0; > + return error; > } > > /* > @@ -2961,12 +2958,6 @@ xfs_read_agf( > error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, > XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)), > XFS_FSS_TO_BB(mp, 1), flags, bpp, &xfs_agf_buf_ops); > - /* > - * Callers of xfs_read_agf() currently interpret a NULL bpp as EAGAIN > - * and need to be converted to check for EAGAIN specifically. > - */ > - if (error == -EAGAIN) > - return 0; > if (error) > return error; > > @@ -2992,14 +2983,15 @@ xfs_alloc_read_agf( > > trace_xfs_alloc_read_agf(mp, agno); > > + /* We don't support trylock when freeing. */ > + ASSERT((flags & (XFS_ALLOC_FLAG_FREEING | XFS_ALLOC_FLAG_TRYLOCK)) != > + (XFS_ALLOC_FLAG_FREEING | XFS_ALLOC_FLAG_TRYLOCK)); Does this assert really work? Shouldn't it be ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING) || !(flags & XFS_ALLOC_FLAG_TRYLOCK)); Otherwise looks good: Reviewed-by: Christoph Hellwig