src: set thread name for main thread and v8 worker

RafaelGSS · targos · commit f4b086d29d70 · 2025-02-07T13:12:46.000+01:00
PR-URL: #56416 Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Santiago Gimeno <santiago.gimeno@gmail.com> Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de> Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>
diff --git a/src/node.cc b/src/node.cc
@@ -1165,6 +1165,7 @@ InitializeOncePerProcessInternal(const std::vector<std::string>& args,
   }
 
   if (!(flags & ProcessInitializationFlags::kNoInitializeNodeV8Platform)) {
+    uv_thread_setname("MainThread");
     per_process::v8_platform.Initialize(
         static_cast<int>(per_process::cli_options->v8_thread_pool_size));
     result->platform_ = per_process::v8_platform.Platform();
diff --git a/src/node_platform.cc b/src/node_platform.cc
@@ -25,6 +25,7 @@ struct PlatformWorkerData {
 };
 
 static void PlatformWorkerThread(void* data) {
+  uv_thread_setname("V8Worker");
   std::unique_ptr<PlatformWorkerData>
       worker_data(static_cast<PlatformWorkerData*>(data));
 
diff --git a/test/addons/uv-thread-name/binding.cc b/test/addons/uv-thread-name/binding.cc
@@ -0,0 +1,29 @@
+#include <node.h>
+#include <uv.h>
+#include <v8.h>
+
+using v8::FunctionCallbackInfo;
+using v8::Isolate;
+using v8::String;
+using v8::Value;
+
+void GetThreadName(const FunctionCallbackInfo<Value>& args) {
+  Isolate* isolate = args.GetIsolate();
+  uv_thread_t thread;
+  char thread_name[16];
+#ifdef _WIN32
+  /* uv_thread_self isn't defined for the main thread on Windows. */
+  thread = GetCurrentThread();
+#else
+  thread = uv_thread_self();
+#endif
+  uv_thread_getname(&thread, thread_name, sizeof(thread_name));
+  args.GetReturnValue().Set(
+      String::NewFromUtf8(isolate, thread_name).ToLocalChecked());
+}
+
+void init(v8::Local<v8::Object> exports) {
+  NODE_SET_METHOD(exports, "getThreadName", GetThreadName);
+}
+
+NODE_MODULE_CONTEXT_AWARE(NODE_GYP_MODULE_NAME, init)
diff --git a/test/addons/uv-thread-name/binding.gyp b/test/addons/uv-thread-name/binding.gyp
@@ -0,0 +1,9 @@
+{
+  'targets': [
+    {
+      'target_name': 'binding',
+      'sources': [ 'binding.cc' ],
+      'includes': ['../common.gypi'],
+    }
+  ]
+}
diff --git a/test/addons/uv-thread-name/test.js b/test/addons/uv-thread-name/test.js
@@ -0,0 +1,35 @@
+'use strict';
+const common = require('../../common');
+
+if (common.isAIX) {
+  common.skip('AIX is not supported by libuv');
+}
+
+const assert = require('node:assert');
+const { parentPort, Worker, isMainThread } = require('node:worker_threads');
+const bindingPath = require.resolve(`./build/${common.buildType}/binding`);
+const binding = require(bindingPath);
+
+if (isMainThread) {
+  assert.strictEqual(binding.getThreadName(), 'MainThread');
+
+  const worker = new Worker(__filename);
+  worker.on('message', common.mustCall((data) => {
+    assert.strictEqual(data, 'WorkerThread');
+  }));
+  worker.on('error', common.mustNotCall());
+  worker.on('exit', common.mustCall((code) => {
+    assert.strictEqual(code, 0);
+  }));
+
+  const namedWorker = new Worker(__filename, { name: 'NamedThread' });
+  namedWorker.on('message', common.mustCall((data) => {
+    assert.strictEqual(data, 'NamedThread');
+  }));
+  namedWorker.on('error', common.mustNotCall());
+  namedWorker.on('exit', common.mustCall((code) => {
+    assert.strictEqual(code, 0);
+  }));
+} else {
+  parentPort.postMessage(binding.getThreadName());
+}

Original file line number	Diff line number	Diff line change
`@@ -1165,6 +1165,7 @@ InitializeOncePerProcessInternal(const std::vector<std::string>& args,`
`1165`	`1165`	`}`
`1166`	`1166`
`1167`	`1167`	`if (!(flags & ProcessInitializationFlags::kNoInitializeNodeV8Platform)) {`
	`1168`	`+ uv_thread_setname("MainThread");`
`1168`	`1169`	`per_process::v8_platform.Initialize(`
`1169`	`1170`	`static_cast<int>(per_process::cli_options->v8_thread_pool_size));`
`1170`	`1171`	`result->platform_ = per_process::v8_platform.Platform();`