From 08485749027f33dd9e6d5df1ec5fc65c7890c53d Mon Sep 17 00:00:00 2001
From: winlin <winlin@vip.126.com>
Date: Sun, 31 Jan 2021 17:27:47 +0800
Subject: [PATCH] Research: Add c++11 thread-local

---
 trunk/.gitignore                             |  2 +
 trunk/research/thread-model/thread-local.cpp | 64 ++++++++++++++++++++
 2 files changed, 66 insertions(+)
 create mode 100644 trunk/research/thread-model/thread-local.cpp

diff --git a/trunk/.gitignore b/trunk/.gitignore
index a67b91615..765dbf701 100644
--- a/trunk/.gitignore
+++ b/trunk/.gitignore
@@ -45,3 +45,5 @@ srs
 /janus
 *.dump
 bug
+/research/thread-model/thread-local
+
diff --git a/trunk/research/thread-model/thread-local.cpp b/trunk/research/thread-model/thread-local.cpp
new file mode 100644
index 000000000..f50553800
--- /dev/null
+++ b/trunk/research/thread-model/thread-local.cpp
@@ -0,0 +1,64 @@
+/*
+g++ -std=c++11 -g -O0 thread-local.cpp -o thread-local
+*/
+#include <stdio.h>
+// @see https://linux.die.net/man/3/pthread_create
+#include <pthread.h>
+
+// Global thread local int variable.
+thread_local int tl_g_nn = 0;
+
+// Global thread local variable object.
+class MyClass
+{
+public:
+    int tl_nn;
+    MyClass(int nn) {
+        tl_nn = nn;
+    }
+};
+
+thread_local MyClass g_obj(0);
+thread_local MyClass* gp_obj = new MyClass(0);
+thread_local MyClass* gp_obj2 = NULL;
+MyClass* get_gp_obj2()
+{
+    if (!gp_obj2) {
+        gp_obj2 = new MyClass(0);
+    }
+    return gp_obj2;
+}
+
+void* pfn(void* arg)
+{
+    int tid = (int)(long long)arg;
+    tl_g_nn += tid;
+    g_obj.tl_nn += tid;
+    gp_obj->tl_nn += tid;
+    get_gp_obj2()->tl_nn += tid;
+
+    printf("PFN%d: tl_g_nn(%p)=%d, g_obj(%p)=%d, gp_obj(%p,%p)=%d, gp_obj2(%p,%p)=%d\n", tid,
+        &tl_g_nn, tl_g_nn, &g_obj, g_obj.tl_nn, &gp_obj, gp_obj, gp_obj->tl_nn,
+        &gp_obj2, gp_obj2, get_gp_obj2()->tl_nn);
+    return NULL;
+}
+
+int main(int argc, char** argv)
+{
+    pthread_t trd = NULL, trd2 = NULL;
+    pthread_create(&trd, NULL, pfn, (void*)1);
+    pthread_create(&trd2, NULL, pfn, (void*)2);
+    pthread_join(trd, NULL);
+    pthread_join(trd2, NULL);
+
+    tl_g_nn += 100;
+    g_obj.tl_nn += 100;
+    gp_obj->tl_nn += 100;
+    get_gp_obj2()->tl_nn += 100;
+
+    printf("MAIN: tl_g_nn(%p)=%d, g_obj(%p)=%d, gp_obj(%p,%p)=%d, gp_obj2(%p,%p)=%d\n",
+        &tl_g_nn, tl_g_nn, &g_obj, g_obj.tl_nn, &gp_obj, gp_obj, gp_obj->tl_nn,
+        &gp_obj2, gp_obj2, get_gp_obj2()->tl_nn);
+    return 0;
+}
+