[Bug] Fix coredump bug when create new tablets

be/src/olap/data_dir.cpp

@@ -992,6 +992,11 @@ void DataDir::update_user_data_size(int64_t size) {
     disks_data_used_capacity->set_value(size);
 }
 
+size_t DataDir::tablet_size() const {
+    std::lock_guard<std::mutex> l(_mutex);
+    return _tablet_set.size();
+}
+
 bool DataDir::reach_capacity_limit(int64_t incoming_data_size) {
     double used_pct = (_disk_capacity_bytes - _available_bytes + incoming_data_size) /
                       (double)_disk_capacity_bytes;

be/src/olap/data_dir.h

@@ -126,7 +126,7 @@ class DataDir {
 
     void update_user_data_size(int64_t size);
 
-    std::set<TabletInfo> tablet_set() { return _tablet_set; }
+    size_t tablet_size() const;
 
     void disks_compaction_score_increment(int64_t delta);
 
@@ -180,7 +180,7 @@ class DataDir {
     bool _to_be_deleted;
 
     // used to protect _current_shard and _tablet_set
-    std::mutex _mutex;
+    mutable std::mutex _mutex;
     uint64_t _current_shard;
     std::set<TabletInfo> _tablet_set;
 

be/src/olap/storage_engine.cpp

@@ -434,7 +434,7 @@ std::vector<DataDir*> StorageEngine::get_stores_for_create_tablet(
     for (int i = 0; i < stores.size(); i++) {
         int j = i + 1;
         if (j < stores.size()) {
-            if (stores[i]->tablet_set().size() > stores[j]->tablet_set().size()) {
+            if (stores[i]->tablet_size() > stores[j]->tablet_size()) {
                 std::swap(stores[i], stores[j]);
             }
             std::random_shuffle(stores.begin() + j, stores.end());