Fix vitastor-kv hang on reopen & unfinished closed listing

src/kv_db.cpp

@@ -197,6 +197,7 @@ struct kv_op_t
 
     void exec();
     void next(); // for list
+    ~kv_op_t();
 protected:
     int recheck_policy = KV_RECHECK_LEAF;
     bool started = false;
@@ -985,14 +986,24 @@ void kv_op_t::exec()
         finish(-ENOSYS);
 }
 
+kv_op_t::~kv_op_t()
+{
+    if (started && !done)
+    {
+        done = true;
+        db->active_ops--;
+    }
+}
+
 void kv_op_t::finish(int res)
 {
+    auto db = this->db;
     this->res = res;
     this->done = true;
     db->active_ops--;
+    (std::function<void(kv_op_t *)>(callback))(this);
     if (!db->active_ops && db->closing)
         db->close(db->on_close);
-    (std::function<void(kv_op_t *)>(callback))(this);
 }
 
 void kv_op_t::get()

src/kv_stress.cpp

@@ -147,6 +147,8 @@ json11::Json::object kv_test_t::parse_args(int narg, const char *args[])
                 "    Fraction of key delete operations\n"
                 "  --list_prob 300\n"
                 "    Fraction of listing operations\n"
+                "  --reopen_prob 1\n"
+                "    Fraction of database reopens\n"
                 "  --min_key_len 10\n"
                 "    Minimum key size in bytes\n"
                 "  --max_key_len 70\n"
@@ -607,10 +609,8 @@ void kv_test_t::add_stat(kv_test_lat_t & stat, timespec tv_begin)
     int64_t usec = (tv_end.tv_sec - tv_begin.tv_sec)*1000000 +
         (tv_end.tv_nsec - tv_begin.tv_nsec)/1000;
     if (usec > 0)
-    {
         stat.usec += usec;
-        stat.count++;
-    }
+    stat.count++;
 }
 
 void kv_test_t::print_stats(kv_test_stat_t & prev_stat, timespec & prev_stat_time)