From 21e50133cbcd1303e3c3eeeed1055406ec2f7a0e Mon Sep 17 00:00:00 2001
From: wangchenguang <darion.yaphets@gmail.com>
Date: Wed, 26 Aug 2026 10:46:08 +0800
Subject: [PATCH] refactor(bthread): make TaskControl metric ownership explicit

Per-tag bvar metrics and cumulative-time callback arguments were created with raw pointers, leaving destruction responsibilities unclear. Store them with unique_ptr while preserving metric names, access patterns, and scheduler behavior.

Constraint: PassiveStatus does not own its callback argument

Rejected: vector<CumulatedWithTagArgs> | reallocation can invalidate callback addresses

Confidence: high

Scope-risk: narrow

Reversibility: clean

Directive: Keep callback arguments alive until after their PassiveStatus is destroyed

Tested: Rebuilt task_control.cpp CMake object target; git diff --check

Not-tested: Full bthread tests are blocked by the existing EPROGREADTIMEOUT build error
---
 src/bthread/task_control.cpp | 20 ++++++++++++++------
 src/bthread/task_control.h   | 13 +++++++++----
 2 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/src/bthread/task_control.cpp b/src/bthread/task_control.cpp
index 5a6bfe831c..6da8a4ab8d 100644
--- a/src/bthread/task_control.cpp
+++ b/src/bthread/task_control.cpp
@@ -258,12 +258,20 @@ int TaskControl::init(int concurrency) {
     for (int i = 0; i < FLAGS_task_group_ntags; ++i) {
         _tagged_ngroup[i].store(0, std::memory_order_relaxed);
         auto tag_str = std::to_string(i);
-        _tagged_nworkers.push_back(new bvar::Adder<int64_t>("bthread_worker_count", tag_str));
-        _tagged_cumulated_worker_time.push_back(new bvar::PassiveStatus<double>(
-            get_cumulated_worker_time_from_this_with_tag, new CumulatedWithTagArgs{this, i}));
-        _tagged_worker_usage_second.push_back(new bvar::PerSecond<bvar::PassiveStatus<double>>(
-            "bthread_worker_usage", tag_str, _tagged_cumulated_worker_time[i], 1));
-        _tagged_nbthreads.push_back(new bvar::Adder<int64_t>("bthread_count", tag_str));
+        _tagged_nworkers.emplace_back(
+            std::make_unique<bvar::Adder<int64_t>>("bthread_worker_count", tag_str));
+        _tagged_cumulated_worker_time_args.emplace_back(
+            std::make_unique<CumulatedWithTagArgs>(this, i));
+        _tagged_cumulated_worker_time.emplace_back(
+            std::make_unique<bvar::PassiveStatus<double>>(
+                get_cumulated_worker_time_from_this_with_tag,
+                _tagged_cumulated_worker_time_args.back().get()));
+        _tagged_worker_usage_second.emplace_back(
+            std::make_unique<bvar::PerSecond<bvar::PassiveStatus<double>>>(
+                "bthread_worker_usage", tag_str,
+                _tagged_cumulated_worker_time.back().get(), 1));
+        _tagged_nbthreads.emplace_back(
+            std::make_unique<bvar::Adder<int64_t>>("bthread_count", tag_str));
     }
 
     if (init_ed_priority_queues() != 0) {
diff --git a/src/bthread/task_control.h b/src/bthread/task_control.h
index 8cc8c4ba4e..fed5bcf3b6 100644
--- a/src/bthread/task_control.h
+++ b/src/bthread/task_control.h
@@ -41,6 +41,7 @@ DECLARE_int32(task_group_ntags);
 namespace bthread {
 
 class TaskGroup;
+struct CumulatedWithTagArgs;
 
 // Control all task groups
 class TaskControl {
@@ -171,10 +172,14 @@ friend bthread_t init_for_pthread_stack_trace();
     bvar::PassiveStatus<std::string> _status;
     bvar::Adder<int64_t> _nbthreads;
 
-    std::vector<bvar::Adder<int64_t>*> _tagged_nworkers;
-    std::vector<bvar::PassiveStatus<double>*> _tagged_cumulated_worker_time;
-    std::vector<bvar::PerSecond<bvar::PassiveStatus<double>>*> _tagged_worker_usage_second;
-    std::vector<bvar::Adder<int64_t>*> _tagged_nbthreads;
+    std::vector<std::unique_ptr<bvar::Adder<int64_t>>> _tagged_nworkers;
+    std::vector<std::unique_ptr<CumulatedWithTagArgs>>
+        _tagged_cumulated_worker_time_args;
+    std::vector<std::unique_ptr<bvar::PassiveStatus<double>>>
+        _tagged_cumulated_worker_time;
+    std::vector<std::unique_ptr<bvar::PerSecond<bvar::PassiveStatus<double>>>>
+        _tagged_worker_usage_second;
+    std::vector<std::unique_ptr<bvar::Adder<int64_t>>> _tagged_nbthreads;
 
     bool _enable_priority_queue;
     int _ed_priority_queue_num_of_each_tag;