From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sunil Mushran Date: Tue, 16 Dec 2008 15:49:19 -0800 Subject: [Ocfs2-devel] [PATCH 5/9] ocfs2/dlm: Fixes race between migrate request and exit domain In-Reply-To: <1229471363-15887-1-git-send-email-sunil.mushran@oracle.com> References: <1229471363-15887-1-git-send-email-sunil.mushran@oracle.com> Message-ID: <1229471363-15887-6-git-send-email-sunil.mushran@oracle.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Patch address a racing migrate request message and an exit domain message. Instead of blocking exit domains for the duration of the migrate, we ignore failure to deliver that message. This is because an exiting domain should not have any active locks and thus has no role to play in the migration. Signed-off-by: Sunil Mushran --- fs/ocfs2/dlm/dlmmaster.c | 23 +++++++++++++++++++---- 1 files changed, 19 insertions(+), 4 deletions(-) diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c index 44f87ca..92fd1d7 100644 --- a/fs/ocfs2/dlm/dlmmaster.c +++ b/fs/ocfs2/dlm/dlmmaster.c @@ -2949,7 +2949,7 @@ static int dlm_do_migrate_request(struct dlm_ctxt *dlm, struct dlm_node_iter *iter) { struct dlm_migrate_request migrate; - int ret, status = 0; + int ret, skip, status = 0; int nodenum; memset(&migrate, 0, sizeof(migrate)); @@ -2966,12 +2966,27 @@ static int dlm_do_migrate_request(struct dlm_ctxt *dlm, nodenum == new_master) continue; + /* We could race exit domain. If exited, skip. */ + spin_lock(&dlm->spinlock); + skip = (!test_bit(nodenum, dlm->domain_map)); + spin_unlock(&dlm->spinlock); + if (skip) { + clear_bit(nodenum, iter->node_map); + continue; + } + ret = o2net_send_message(DLM_MIGRATE_REQUEST_MSG, dlm->key, &migrate, sizeof(migrate), nodenum, &status); - if (ret < 0) - mlog_errno(ret); - else if (status < 0) { + if (ret < 0) { + mlog(0, "migrate_request returned %d!\n", ret); + if (!dlm_is_host_down(ret)) { + mlog(ML_ERROR, "unhandled error=%d!\n", ret); + BUG(); + } + clear_bit(nodenum, iter->node_map); + ret = 0; + } else if (status < 0) { mlog(0, "migrate request (node %u) returned %d!\n", nodenum, status); ret = status; -- 1.5.6.3