glusterd: stop stale bricks during handshaking in brick mux mode

This patch addresses two problems:

1. During friend handshaking, if a volume is imported due to change in
the version, the old bricks were not stopped which would lead to a
situation where bricks will run with old volfiles.

2. As part of attaching shd service in glusterd_attach_svc, there might
be a case that the volume for which we're attempting to attach a shd
service might become stale and in the process of deletion and hence in
every retrials (if the rpc connection isn't ready) check for the
existance of the volume and then only attempt the further attach
request.

patch on master: https://review.gluster.org/#/c/glusterfs/+/23042/

> Bug: bz#1733425
> Change-Id: I6bac6b871f7e31cb5bf277db979289dec196a03e
> Signed-off-by: Atin Mukherjee <amukherj@redhat.com>
> Signed-off-by: Mohammed Rafi KC <rkavunga@redhat.com>

fixes: bz#1812849
Change-Id: I6bac6b871f7e31cb5bf277db979289dec196a03e
Signed-off-by: Sanju Rakonde <srakonde@redhat.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-svc-helper.c b/xlators/mgmt/glusterd/src/glusterd-svc-helper.c
index e4924f831b7..5042d8e85f5 100644
--- a/xlators/mgmt/glusterd/src/glusterd-svc-helper.c
+++ b/xlators/mgmt/glusterd/src/glusterd-svc-helper.c
@@ -902,6 +902,22 @@ glusterd_attach_svc(glusterd_svc_t *svc, glusterd_volinfo_t *volinfo, int flags)
 
     rpc = rpc_clnt_ref(svc->conn.rpc);
     for (tries = 15; tries > 0; --tries) {
+        /* There might be a case that the volume for which we're attempting to
+         * attach a shd svc might become stale and in the process of deletion.
+         * Given that the volinfo object is being already passed here before
+         * that sequence of operation has happened we might be operating on a
+         * stale volume. At every sync task switch we should check for existance
+         * of the volume now
+         */
+        if (!glusterd_volume_exists(volinfo->volname)) {
+            gf_msg(THIS->name, GF_LOG_INFO, 0, GD_MSG_SVC_ATTACH_FAIL,
+                   "Volume %s "
+                   " is marked as stale, not attempting further shd svc attach "
+                   "attempts",
+                   volinfo->volname);
+            ret = 0;
+            goto out;
+        }
         if (rpc) {
             pthread_mutex_lock(&conf->attach_lock);
             {