osd: is_zero() method for stat structs

Signed-off-by: Sage Weil <sage@newdream.net>

diff --git a/src/osd/osd_types.h b/src/osd/osd_types.h
index d0ed168f01bcd5f0dcf8f5effabbff9f7e8e7b42..65bcb55c1563b4e90b532479b7320f183265e966 100644 (file)
--- a/src/osd/osd_types.h
+++ b/src/osd/osd_types.h
@@ -675,6 +675,11 @@ struct object_stat_sum_t {
     num_object_copies = nrep * num_objects;
   }
 
+  bool is_zero() const {
+    object_stat_sum_t zero;
+    return memcmp(this, &zero, sizeof(zero)) == 0;
+  }
+
   void add(const object_stat_sum_t& o);
   void sub(const object_stat_sum_t& o);
 
@@ -705,6 +710,10 @@ struct object_stat_collection_t {
   void decode(bufferlist::iterator& bl);
   static void generate_test_instances(list<object_stat_collection_t*>& o);
 
+  bool is_zero() const {
+    return (cat_sum.empty() && sum.is_zero());
+  }
+
   void clear() {
     sum.clear();
     cat_sum.clear();
@@ -727,8 +736,12 @@ struct object_stat_collection_t {
     sum.sub(o.sum);
     for (map<string,object_stat_sum_t>::const_iterator p = o.cat_sum.begin();
         p != o.cat_sum.end();
-        ++p)
-      cat_sum[p->first].sub(p->second);
+        ++p) {
+      object_stat_sum_t& s = cat_sum[p->first];
+      s.sub(p->second);
+      if (s.is_zero())
+       cat_sum.erase(p->first);
+    }
   }
 };
 WRITE_CLASS_ENCODER(object_stat_collection_t)
@@ -807,6 +820,12 @@ struct pool_stat_t {
     ondisk_log_size -= o.ondisk_log_size;
   }
 
+  bool is_zero() const {
+    return (stats.is_zero() &&
+           log_size == 0 &&
+           ondisk_log_size == 0);
+  }
+
   void dump(Formatter *f) const;
   void encode(bufferlist &bl) const;
   void decode(bufferlist::iterator &bl);