From 38fb4cc3c48616f80816b65ca0e7fa4b5c7793d6 Mon Sep 17 00:00:00 2001
From: winlin <winlin@vip.126.com>
Date: Fri, 12 Mar 2021 12:02:36 +0800
Subject: [PATCH] For #2188: Refine thread lock type to ERRORCHECK.

1. Set lock attribute type to PTHREAD_MUTEX_ERRORCHECK.
2. If dead lock, the pthread_mutex_lock return EDEADLK.
3. We assert fail if lock failed.
---
 trunk/src/app/srs_app_threads.cpp | 22 ++++++++++++++++++++--
 trunk/src/app/srs_app_threads.hpp |  4 +++-
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/trunk/src/app/srs_app_threads.cpp b/trunk/src/app/srs_app_threads.cpp
index 5ee814fd48b..7cdf0ea0976 100644
--- a/trunk/src/app/srs_app_threads.cpp
+++ b/trunk/src/app/srs_app_threads.cpp
@@ -34,8 +34,16 @@ using namespace std;
 
 SrsThreadMutex::SrsThreadMutex()
 {
+    // https://man7.org/linux/man-pages/man3/pthread_mutexattr_init.3.html
+    int r0 = pthread_mutexattr_init(&attr_);
+    srs_assert(!r0);
+
+    // https://man7.org/linux/man-pages/man3/pthread_mutexattr_gettype.3p.html
+    r0 = pthread_mutexattr_settype(&attr_, PTHREAD_MUTEX_ERRORCHECK);
+    srs_assert(!r0);
+
     // https://michaelkerrisk.com/linux/man-pages/man3/pthread_mutex_init.3p.html
-    int r0 = pthread_mutex_init(&lock_, NULL);
+    r0 = pthread_mutex_init(&lock_, &attr_);
     srs_assert(!r0);
 }
 
@@ -43,11 +51,17 @@ SrsThreadMutex::~SrsThreadMutex()
 {
     int r0 = pthread_mutex_destroy(&lock_);
     srs_assert(!r0);
+
+    r0 = pthread_mutexattr_destroy(&attr_);
+    srs_assert(!r0);
 }
 
 void SrsThreadMutex::lock()
 {
     // https://man7.org/linux/man-pages/man3/pthread_mutex_lock.3p.html
+    //        EDEADLK
+    //                 The mutex type is PTHREAD_MUTEX_ERRORCHECK and the current
+    //                 thread already owns the mutex.
     int r0 = pthread_mutex_lock(&lock_);
     srs_assert(!r0);
 }
@@ -68,6 +82,10 @@ SrsThreadEntry::SrsThreadEntry()
     err = srs_success;
 }
 
+SrsThreadEntry::~SrsThreadEntry()
+{
+}
+
 SrsThreadPool::SrsThreadPool()
 {
     entry_ = NULL;
@@ -127,7 +145,7 @@ srs_error_t SrsThreadPool::execute(string label, srs_error_t (*start)(void* arg)
     pthread_t trd;
     int r0 = pthread_create(&trd, NULL, SrsThreadPool::start, entry);
     if (r0 != 0) {
-        entry->err = srs_error_new(ERROR_THREAD_CREATE, "create thread %s", label.c_str());
+        entry->err = srs_error_new(ERROR_THREAD_CREATE, "create thread %s, r0=%d", label.c_str(), r0);
         return srs_error_copy(entry->err);
     }
 
diff --git a/trunk/src/app/srs_app_threads.hpp b/trunk/src/app/srs_app_threads.hpp
index ad86f58a706..6458e01f037 100644
--- a/trunk/src/app/srs_app_threads.hpp
+++ b/trunk/src/app/srs_app_threads.hpp
@@ -38,6 +38,7 @@ class SrsThreadMutex
 {
 private:
     pthread_mutex_t lock_;
+    pthread_mutexattr_t attr_;
 public:
     SrsThreadMutex();
     virtual ~SrsThreadMutex();
@@ -78,8 +79,9 @@ class SrsThreadEntry
     pthread_t trd;
     // The exit error of thread.
     srs_error_t err;
-
+public:
     SrsThreadEntry();
+    virtual ~SrsThreadEntry();
 };
 
 // Allocate a(or almost) fixed thread poll to execute tasks,