osd: subscribe osdmaps if any pending pgs

subscribe from monitor continously for new osdmaps so osd is able to get
the osdmap instructing it to delete PGs even if nobody is poking it.

Fixes: http://tracker.ceph.com/issues/22113
Signed-off-by: Kefu Chai <kchai@redhat.com>
(cherry picked from commit 4037ab44b30ab23b2e464b24a82fee6fff9a2d08)

diff --git a/src/osd/OSD.cc b/src/osd/OSD.cc
index 926a3be7e03422c9a9bff9e4f3c5914385020110..4dcb3940cf4a40ade912b78a96b05fd33f3ab0ac 100644 (file)
--- a/src/osd/OSD.cc
+++ b/src/osd/OSD.cc
@@ -4458,6 +4458,7 @@ static vector<int32_t> twiddle(const vector<int>& acting) {
 void OSD::resume_creating_pg()
 {
   bool do_sub_pg_creates = false;
+  bool have_pending_creates = false;
   MOSDPGTemp *pgtemp = nullptr;
   {
     const auto max_pgs_per_osd =
@@ -4490,14 +4491,40 @@ void OSD::resume_creating_pg()
       pg = pending_creates_from_osd.erase(pg);
       spare_pgs--;
     }
+    have_pending_creates = (pending_creates_from_mon > 0 ||
+                           !pending_creates_from_osd.empty());
   }
+
+  bool do_renew_subs = false;
   if (do_sub_pg_creates) {
     if (monc->sub_want("osd_pg_creates", last_pg_create_epoch, 0)) {
       dout(4) << __func__ << ": resolicit pg creates from mon since "
              << last_pg_create_epoch << dendl;
-      monc->renew_subs();
+      do_renew_subs = true;
+    }
+  }
+  version_t start = osdmap->get_epoch() + 1;
+  if (have_pending_creates) {
+    // don't miss any new osdmap deleting PGs
+    if (monc->sub_want("osdmap", start, 0)) {
+      dout(4) << __func__ << ": resolicit osdmap from mon since "
+             << start << dendl;
+      do_renew_subs = true;
+    }
+  } else if (pgtemp || do_sub_pg_creates) {
+    // no need to subscribe the osdmap continuously anymore
+    // once the pgtemp and/or mon_subscribe(pg_creates) is sent
+    if (monc->sub_want_increment("osdmap", start, CEPH_SUBSCRIBE_ONETIME)) {
+      dout(4) << __func__ << ": re-subscribe osdmap(onetime) since"
+             << start << dendl;
+      do_renew_subs = true;
     }
   }
+
+  if (do_renew_subs) {
+    monc->renew_subs();
+  }
+
   if (pgtemp) {
     pgtemp->forced = true;
     monc->send_mon_message(pgtemp);