cman members are queried in response to a callback,
and members sometimes leave and rejoin between queries
(e.g. when they leave and rejoin before corosync
detects they left.)

This means that simply checking if a node is a member
in consecutive queries sometimes misses events. We
need to compare the incarnation numbers of members
from consecutive queries to avoid this.

bz 663397

Signed-off-by: David Teigland <teigland@redhat.com>
---
group/gfs_controld/member_cman.c | 51 +++++++++++++++++++++++++++++++++++---
1 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/group/gfs_controld/member_cman.c b/group/gfs_controld/member_cman.c
index 277a11e..7f354b1 100644
--- a/group/gfs_controld/member_cman.c
+++ b/group/gfs_controld/member_cman.c
@@ -9,6 +9,7 @@ static cman_node_t old_nodes[MAX_NODES];
static int old_node_count;
static cman_node_t cman_nodes[MAX_NODES];
static int cman_node_count;
+static uint32_t cluster_ringid_seq;

void kick_node_from_cluster(int nodeid)
{
@@ -22,6 +23,17 @@ void kick_node_from_cluster(int nodeid)
}
}

+static cman_node_t *get_node(cman_node_t *node_list, int count, int nodeid)
+{
+ int i;
+
+ for (i = 0; i < count; i++) {
+ if (node_list[i].cn_nodeid == nodeid)
+ return &node_list[i];
+ }
+ return NULL;
+}
+
static int is_member(cman_node_t *node_list, int count, int nodeid)
{
int i;
@@ -45,8 +57,18 @@ static int is_cluster_member(int nodeid)

static void statechange(void)
{
+ cman_cluster_t info;
+ cman_node_t *old;
int i, rv;

+ rv = cman_get_cluster(ch, &info);
+ if (rv < 0) {
+ log_error("cman_get_cluster error %d %d", rv, errno);
+ /* keep going, this is just informational */
+ memset(&info, 0, sizeof(info));
+ }
+ cluster_ringid_seq = info.ci_generation;
+
old_node_count = cman_node_count;
memcpy(&old_nodes, &cman_nodes, sizeof(old_nodes));

@@ -70,8 +92,8 @@ static void statechange(void)
if (old_nodes[i].cn_member &&
!is_cluster_member(old_nodes[i].cn_nodeid)) {

- log_debug("cluster node %d removed",
- old_nodes[i].cn_nodeid);
+ log_debug("cluster node %d removed seq %u",
+ old_nodes[i].cn_nodeid, cluster_ringid_seq);

node_history_cluster_remove(old_nodes[i].cn_nodeid);
}
@@ -81,10 +103,31 @@ static void statechange(void)
if (cman_nodes[i].cn_member &&
!is_old_member(cman_nodes[i].cn_nodeid)) {

- log_debug("cluster node %d added",
- cman_nodes[i].cn_nodeid);
+ log_debug("cluster node %d added seq %u",
+ cman_nodes[i].cn_nodeid, cluster_ringid_seq);

node_history_cluster_add(cman_nodes[i].cn_nodeid);
+ } else {
+ /* look for any nodes that were members of both
+ * old and new but have a new incarnation number
+ * from old to new, indicating they left and rejoined
+ * in between */
+
+ old = get_node(old_nodes, old_node_count, cman_nodes[i].cn_nodeid);
+
+ if (!old)
+ continue;
+ if (cman_nodes[i].cn_incarnation == old->cn_incarnation)
+ continue;
+
+ log_debug("cluster node %d removed and added seq %u "
+ "old %u new %u",
+ cman_nodes[i].cn_nodeid, cluster_ringid_seq,
+ old->cn_incarnation,
+ cman_nodes[i].cn_incarnation);
+
+ node_history_cluster_remove(cman_nodes[i].cn_nodeid);
+ node_history_cluster_add(cman_nodes[i].cn_nodeid);
}
}
}
--
1.7.6