From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp2120.oracle.com ([156.151.31.85]:51430 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727732AbeJaCjJ (ORCPT ); Tue, 30 Oct 2018 22:39:09 -0400 Date: Tue, 30 Oct 2018 10:44:34 -0700 From: "Darrick J. Wong" Subject: Re: [PATCH 5/7] repair: Protect bad inode list with mutex Message-ID: <20181030174434.GJ4135@magnolia> References: <20181030112043.6034-1-david@fromorbit.com> <20181030112043.6034-6-david@fromorbit.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181030112043.6034-6-david@fromorbit.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Dave Chinner Cc: linux-xfs@vger.kernel.org On Tue, Oct 30, 2018 at 10:20:41PM +1100, Dave Chinner wrote: > From: Dave Chinner > > To enable phase 6 parallelisation, we need to protect the bad inode > list from concurrent modification and/or access. Wrap it with a > mutex and clean up the nasty typedefs. > > Signed-off-by: Dave Chinner > --- > repair/dir2.c | 32 +++++++++++++++++++++----------- > 1 file changed, 21 insertions(+), 11 deletions(-) > > diff --git a/repair/dir2.c b/repair/dir2.c > index ba5763ed3d26..a73a675b97c8 100644 > --- a/repair/dir2.c > +++ b/repair/dir2.c > @@ -20,40 +20,50 @@ > * Known bad inode list. These are seen when the leaf and node > * block linkages are incorrect. > */ > -typedef struct dir2_bad { > +struct dir2_bad { > xfs_ino_t ino; > struct dir2_bad *next; > -} dir2_bad_t; > +}; Just out of curiosity, how fast does this linked list grow? In theory we could hoist scrub/bitmap.c to libfrog and turn this into a bitmap, but that probably depends on how often we find inodes with bad link counts...? And admittedly, avlnodes aren't cheap either... Anyway, this patch itself looks ok, Reviewed-by: Darrick J. Wong --D > > -static dir2_bad_t *dir2_bad_list; > +static struct dir2_bad *dir2_bad_list; > +pthread_mutex_t dir2_bad_list_lock = PTHREAD_MUTEX_INITIALIZER; > > static void > dir2_add_badlist( > xfs_ino_t ino) > { > - dir2_bad_t *l; > + struct dir2_bad *l; > > - if ((l = malloc(sizeof(dir2_bad_t))) == NULL) { > + l = malloc(sizeof(*l)); > + if (!l) { > do_error( > _("malloc failed (%zu bytes) dir2_add_badlist:ino %" PRIu64 "\n"), > - sizeof(dir2_bad_t), ino); > + sizeof(*l), ino); > exit(1); > } > + pthread_mutex_lock(&dir2_bad_list_lock); > l->next = dir2_bad_list; > dir2_bad_list = l; > l->ino = ino; > + pthread_mutex_unlock(&dir2_bad_list_lock); > } > > int > dir2_is_badino( > xfs_ino_t ino) > { > - dir2_bad_t *l; > + struct dir2_bad *l; > + int ret = 0; > > - for (l = dir2_bad_list; l; l = l->next) > - if (l->ino == ino) > - return 1; > - return 0; > + pthread_mutex_lock(&dir2_bad_list_lock); > + for (l = dir2_bad_list; l; l = l->next) { > + if (l->ino == ino) { > + ret = 1; > + break; > + } > + } > + pthread_mutex_unlock(&dir2_bad_list_lock); > + return ret; > } > > /* > -- > 2.19.1 >