From fda54706886c3372a95d3720bed5a5c5aaa79a22 Mon Sep 17 00:00:00 2001
From: Daniele <dan83h@live.it>
Date: Thu, 12 Jan 2017 18:56:02 +0100
Subject: [PATCH] Replace the spinlock on ProxySQL_Admin::wrlock with a pthread
 mutex or wrlock

---
 include/proxy_defines.h  |  4 ++++
 include/proxysql_admin.h | 13 +++++++++++++
 lib/ProxySQL_Admin.cpp   | 22 ++++++++++++++++++++--
 3 files changed, 37 insertions(+), 2 deletions(-)
 create mode 100644 include/proxy_defines.h

diff --git a/include/proxy_defines.h b/include/proxy_defines.h
new file mode 100644
index 000000000..20b0bfa1c
--- /dev/null
+++ b/include/proxy_defines.h
@@ -0,0 +1,4 @@
+
+// If defined then active pthread mutex in ProxySQL_Admin else use the wrlock
+#define PA_PTHREAD_MUTEX
+
diff --git a/include/proxysql_admin.h b/include/proxysql_admin.h
index 312384aad..654cb35e6 100644
--- a/include/proxysql_admin.h
+++ b/include/proxysql_admin.h
@@ -1,5 +1,7 @@
 #ifndef __CLASS_PROXYSQL_ADMIN_H
 #define __CLASS_PROXYSQL_ADMIN_H
+
+#include "proxy_defines.h"
 #include "proxysql.h"
 #include "cpp.h"
 #include <vector>
@@ -58,8 +60,19 @@ class ProxySQL_Admin {
 	int main_poll_nfds;
 	struct pollfd *main_poll_fds;
 	int *main_callback_func;
+
+
 	rwlock_t rwlock;
+
+#ifdef PA_PTHREAD_MUTEX
+	pthread_mutex_t mysql_servers_lock;
+#else
 	rwlock_t mysql_servers_rwlock;
+#endif
+
+	
+
+
 	void wrlock();
 	void wrunlock();
 
diff --git a/lib/ProxySQL_Admin.cpp b/lib/ProxySQL_Admin.cpp
index 820eff25a..48cee39c0 100644
--- a/lib/ProxySQL_Admin.cpp
+++ b/lib/ProxySQL_Admin.cpp
@@ -2450,8 +2450,18 @@ ProxySQL_Admin::ProxySQL_Admin() {
 		}
 
 	SPA=this;
+
+	//Initialize locker
 	spinlock_rwlock_init(&rwlock);
+
+#ifdef PA_PTHREAD_MUTEX
+	pthread_mutex_init(&mysql_servers_lock, NULL);
+#else
 	spinlock_rwlock_init(&mysql_servers_rwlock);
+#endif
+
+
+
 	variables.admin_credentials=strdup("admin:admin");
 	variables.stats_credentials=strdup("stats:stats");
 	if (GloVars.__cmd_proxysql_admin_socket) {
@@ -2493,11 +2503,19 @@ void ProxySQL_Admin::wrunlock() {
 };
 
 void ProxySQL_Admin::mysql_servers_wrlock() {
-	spin_wrlock(&mysql_servers_rwlock);
+	#ifdef PA_PTHREAD_MUTEX
+		pthread_mutex_lock(&mysql_servers_lock);
+	#else
+		spin_wrlock(&mysql_servers_rwlock);
+	#endif
 };
 
 void ProxySQL_Admin::mysql_servers_wrunlock() {
-	spin_wrunlock(&mysql_servers_rwlock);
+	#ifdef PA_PTHREAD_MUTEX
+		pthread_mutex_unlock(&mysql_servers_lock);
+	#else
+		spin_wrunlock(&mysql_servers_rwlock);
+	#endif
 };
 
 void ProxySQL_Admin::print_version() {