osd/OSDMap: include pg_temp count in summary

It is useful to know how big the pg_temp map is.  Strictly speaking
this is part of the OSDMap so I'm including it here.  It looks like
this:

     osdmap e25: 3 osds: 3 up, 3 in; 1 remapped pgs

It might be more user-friendly to put it in a line with the pgmap
somewhere (where other pg counts are included), but it doesn't quite
fit there either.  So sticking with where it lives in the data
structure!

Signed-off-by: Sage Weil <[email protected]>
(cherry picked from commit db06582)

src/osd/OSDMap.cc

@@ -2575,12 +2575,16 @@ void OSDMap::print_summary(Formatter *f, ostream& out) const
     f->dump_int("num_in_osds", get_num_in_osds());
     f->dump_bool("full", test_flag(CEPH_OSDMAP_FULL) ? true : false);
     f->dump_bool("nearfull", test_flag(CEPH_OSDMAP_NEARFULL) ? true : false);
+    f->dump_unsigned("num_remapped_pgs", get_num_pg_temp());
     f->close_section();
   } else {
     out << "     osdmap e" << get_epoch() << ": "
 	<< get_num_osds() << " osds: "
 	<< get_num_up_osds() << " up, "
-	<< get_num_in_osds() << " in\n";
+	<< get_num_in_osds() << " in";
+    if (get_num_pg_temp())
+      out << "; " << get_num_pg_temp() << " remapped pgs";
+    out << "\n";
     if (flags)
       out << "            flags " << get_flag_string() << "\n";
   }

src/osd/OSDMap.h

@@ -331,6 +331,9 @@ class OSDMap {
   void get_up_osds(set<int32_t>& ls) const;
   unsigned get_num_up_osds() const;
   unsigned get_num_in_osds() const;
+  unsigned get_num_pg_temp() const {
+    return pg_temp->size();
+  }
 
   int get_flags() const { return flags; }
   int test_flag(int f) const { return flags & f; }