glusterd: handling brick termination in brick-mux

Problem: There's a race between the glusterfs_handle_terminate()
response sent to glusterd from last brick of the process and the
socket disconnect event that encounters after the brick process
got killed.

Solution: When it is a last brick for the brick process, instead of
sending GLUSTERD_BRICK_TERMINATE to brick process, glusterd will
kill the process (same as we do it in case of non brick multiplecing).

The test case is added for https://bugzilla.redhat.com/show_bug.cgi?id=1549996

Change-Id: If94958cd7649ea48d09d6af7803a0f9437a85503
fixes: bz#1545048
Signed-off-by: Sanju Rakonde <srakonde@redhat.com>

4 files changed, 11 insertions, 23 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-pmap.c b/xlators/mgmt/glusterd/src/glusterd-pmap.c
index 98b1aaa63af..989d13ecde7 100644
--- a/xlators/mgmt/glusterd/src/glusterd-pmap.c
+++ b/xlators/mgmt/glusterd/src/glusterd-pmap.c
@@ -606,7 +606,8 @@ __gluster_pmap_signout (rpcsvc_request_t *req)
                          * removed in the brick op phase. This situation would
                          * arise when the brick is killed explicitly from the
                          * backend */
-                        ret = glusterd_brick_process_remove_brick (brickinfo);
+                        ret = glusterd_brick_process_remove_brick (brickinfo,
+                                                                   NULL);
                         if (ret) {
                                 gf_msg_debug (this->name, 0, "Couldn't remove "
                                               "brick %s:%s from brick process",
diff --git a/xlators/mgmt/glusterd/src/glusterd-syncop.c b/xlators/mgmt/glusterd/src/glusterd-syncop.c
index 31b08d76adc..e5d4421deb4 100644
--- a/xlators/mgmt/glusterd/src/glusterd-syncop.c
+++ b/xlators/mgmt/glusterd/src/glusterd-syncop.c
@@ -958,7 +958,6 @@ gd_syncop_mgmt_brick_op (struct rpc_clnt *rpc, glusterd_pending_node_t *pnode,
         gd1_mgmt_brick_op_req  *req  = NULL;
         int                    ret  = 0;
         xlator_t               *this = NULL;
-        glusterd_brickinfo_t   *brickinfo = NULL;
 
         this = THIS;
         args.op_ret = -1;
@@ -987,22 +986,6 @@ gd_syncop_mgmt_brick_op (struct rpc_clnt *rpc, glusterd_pending_node_t *pnode,
                 else
                         GF_FREE (args.errstr);
         }
-        if (op == GD_OP_STOP_VOLUME || op == GD_OP_REMOVE_BRICK) {
-                if (args.op_ret == 0) {
-                        brickinfo = pnode->node;
-                        ret = glusterd_brick_process_remove_brick (brickinfo);
-                        if (ret) {
-                                gf_msg ("glusterd", GF_LOG_ERROR, 0,
-                                        GD_MSG_BRICKPROC_REM_BRICK_FAILED,
-                                        "Removing brick %s:%s from brick"
-                                        " process failed",
-                                        brickinfo->hostname,
-                                        brickinfo->path);
-                                args.op_ret = ret;
-                                goto out;
-                        }
-                }
-        }
 
         if (GD_OP_STATUS_VOLUME == op) {
                 ret = dict_set_int32 (args.dict, "index", pnode->index);
diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index 42a4411d92e..88aea178028 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -2313,7 +2313,8 @@ glusterd_brickprocess_delete (glusterd_brick_proc_t *brick_proc)
 }
 
 int
-glusterd_brick_process_remove_brick (glusterd_brickinfo_t *brickinfo)
+glusterd_brick_process_remove_brick (glusterd_brickinfo_t *brickinfo,
+                                     int *last_brick)
 {
         int                      ret = -1;
         xlator_t                *this = NULL;
@@ -2352,6 +2353,8 @@ glusterd_brick_process_remove_brick (glusterd_brickinfo_t *brickinfo)
 
                 /* If all bricks have been removed, delete the brick process */
                 if (brick_proc->brick_count == 0) {
+                        if (last_brick != NULL)
+                                *last_brick = 1;
                         ret = glusterd_brickprocess_delete (brick_proc);
                         if (ret)
                                 goto out;
@@ -2455,6 +2458,7 @@ glusterd_volume_stop_glusterfs (glusterd_volinfo_t *volinfo,
         int             ret                     = -1;
         char            *op_errstr              = NULL;
         char            pidfile[PATH_MAX]       = {0,};
+        int             last_brick              = -1;
 
         GF_ASSERT (volinfo);
         GF_ASSERT (brickinfo);
@@ -2467,7 +2471,7 @@ glusterd_volume_stop_glusterfs (glusterd_volinfo_t *volinfo,
 
         ret = 0;
 
-        ret = glusterd_brick_process_remove_brick (brickinfo);
+        ret = glusterd_brick_process_remove_brick (brickinfo, &last_brick);
         if (ret) {
                 gf_msg_debug (this->name, 0, "Couldn't remove brick from"
                               " brick process");
@@ -2487,7 +2491,7 @@ glusterd_volume_stop_glusterfs (glusterd_volinfo_t *volinfo,
                  * attaching and detaching bricks).  Therefore, we have to send
                  * an actual signal instead.
                  */
-                if (is_brick_mx_enabled ()) {
+                if (is_brick_mx_enabled () && last_brick != 1) {
                         gf_msg_debug (this->name, 0, "About to send detach "
                                       "request for brick %s:%s",
                                       brickinfo->hostname, brickinfo->path);
@@ -2511,7 +2515,6 @@ glusterd_volume_stop_glusterfs (glusterd_volinfo_t *volinfo,
         }
 
         GLUSTERD_GET_BRICK_PIDFILE (pidfile, volinfo, brickinfo, conf);
-
         gf_msg_debug (this->name,  0, "Unlinking pidfile %s", pidfile);
         (void) sys_unlink (pidfile);
 
diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.h b/xlators/mgmt/glusterd/src/glusterd-utils.h
index 0e9e54a0687..b1209728b67 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.h
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.h
@@ -182,7 +182,8 @@ glusterd_brick_process_add_brick (glusterd_brickinfo_t *brickinfo,
                                   glusterd_volinfo_t *volinfo);
 
 int
-glusterd_brick_process_remove_brick (glusterd_brickinfo_t *brickinfo);
+glusterd_brick_process_remove_brick (glusterd_brickinfo_t *brickinfo,
+                                     int *last_brick);
 
 int
 glusterd_brick_proc_for_port (int port, glusterd_brick_proc_t **brickprocess);