From 7d6255c8605bd18a7c7d90de19346392a51c90b7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Paczos?= <lukas.paczos@gmail.com>
Date: Tue, 21 May 2019 12:45:01 +0200
Subject: [PATCH] [core] option to perform platform specific operations when
 creating/destroying core threads

---
 include/mbgl/platform/thread.hpp          | 13 +++++++++++++
 include/mbgl/util/thread.hpp              |  3 +++
 platform/android/src/thread.cpp           |  7 +++++++
 platform/darwin/src/nsthread.mm           |  7 +++++++
 platform/default/src/mbgl/util/thread.cpp |  7 +++++++
 platform/qt/src/thread.cpp                |  7 +++++++
 src/core-files.json                       |  1 +
 src/mbgl/util/thread_pool.cpp             |  3 +++
 8 files changed, 48 insertions(+)
 create mode 100644 include/mbgl/platform/thread.hpp

diff --git a/include/mbgl/platform/thread.hpp b/include/mbgl/platform/thread.hpp
new file mode 100644
index 000000000..72899a4fd
--- /dev/null
+++ b/include/mbgl/platform/thread.hpp
@@ -0,0 +1,13 @@
+#pragma once
+
+namespace mbgl {
+namespace platform {
+
+// Called when a thread is created
+void attachThread();
+
+// Called when a thread is destroyed
+void detachThread();
+
+} // namespace platform
+} // namespace mbgl
diff --git a/include/mbgl/util/thread.hpp b/include/mbgl/util/thread.hpp
index bc5842734..0e9bd8f75 100644
--- a/include/mbgl/util/thread.hpp
+++ b/include/mbgl/util/thread.hpp
@@ -6,6 +6,7 @@
 #include <mbgl/util/platform.hpp>
 #include <mbgl/util/run_loop.hpp>
 #include <mbgl/util/util.hpp>
+#include <mbgl/platform/thread.hpp>
 
 #include <cassert>
 #include <future>
@@ -55,6 +56,7 @@ public:
         ] () mutable {
             platform::setCurrentThreadName(name);
             platform::makeThreadLowPriority();
+            platform::attachThread();
 
             util::RunLoop loop_(util::RunLoop::Type::New);
             loop = &loop_;
@@ -67,6 +69,7 @@ public:
             (void) establishedActor;
             
             loop = nullptr;
+            platform::detachThread();
         });
     }
 
diff --git a/platform/android/src/thread.cpp b/platform/android/src/thread.cpp
index c708dfdce..721c63a53 100644
--- a/platform/android/src/thread.cpp
+++ b/platform/android/src/thread.cpp
@@ -1,5 +1,6 @@
 #include <mbgl/util/logging.hpp>
 #include <mbgl/util/platform.hpp>
+#include <mbgl/platform/thread.hpp>
 
 #include <sys/prctl.h>
 #include <sys/resource.h>
@@ -33,5 +34,11 @@ void makeThreadLowPriority() {
     setpriority(PRIO_PROCESS, 0, 19);
 }
 
+void attachThread() {
+}
+
+void detachThread() {
+}
+
 } // namespace platform
 } // namespace mbgl
diff --git a/platform/darwin/src/nsthread.mm b/platform/darwin/src/nsthread.mm
index 458db968d..f7edcdf5d 100644
--- a/platform/darwin/src/nsthread.mm
+++ b/platform/darwin/src/nsthread.mm
@@ -1,6 +1,7 @@
 #import <Foundation/Foundation.h>
 
 #include <mbgl/util/platform.hpp>
+#include <mbgl/platform/thread.hpp>
 
 #include <pthread.h>
 
@@ -23,5 +24,11 @@ void makeThreadLowPriority() {
     [[NSThread currentThread] setThreadPriority:0.0];
 }
 
+void attachThread() {
+}
+
+void detachThread() {
+}
+
 }
 }
diff --git a/platform/default/src/mbgl/util/thread.cpp b/platform/default/src/mbgl/util/thread.cpp
index c7c79b4fb..28772d956 100644
--- a/platform/default/src/mbgl/util/thread.cpp
+++ b/platform/default/src/mbgl/util/thread.cpp
@@ -1,4 +1,5 @@
 #include <mbgl/util/platform.hpp>
+#include <mbgl/platform/thread.hpp>
 #include <mbgl/util/logging.hpp>
 
 #include <string>
@@ -33,5 +34,11 @@ void makeThreadLowPriority() {
     }
 }
 
+void attachThread() {
+}
+
+void detachThread() {
+}
+
 } // namespace platform
 } // namespace mbgl
diff --git a/platform/qt/src/thread.cpp b/platform/qt/src/thread.cpp
index ade3629b6..103b6d74f 100644
--- a/platform/qt/src/thread.cpp
+++ b/platform/qt/src/thread.cpp
@@ -1,4 +1,5 @@
 #include <mbgl/util/platform.hpp>
+#include <mbgl/platform/thread.hpp>
 
 #include <string>
 
@@ -15,5 +16,11 @@ void setCurrentThreadName(const std::string&) {
 void makeThreadLowPriority() {
 }
 
+void attachThread() {
+}
+
+void detachThread() {
+}
+
 } // namespace platform
 } // namespace mbgl
diff --git a/src/core-files.json b/src/core-files.json
index 2385b18c3..05870661d 100644
--- a/src/core-files.json
+++ b/src/core-files.json
@@ -351,6 +351,7 @@
         "mbgl/math/minmax.hpp": "include/mbgl/math/minmax.hpp",
         "mbgl/math/wrap.hpp": "include/mbgl/math/wrap.hpp",
         "mbgl/platform/gl_functions.hpp": "include/mbgl/platform/gl_functions.hpp",
+        "mbgl/platform/thread.hpp": "include/mbgl/platform/thread.hpp",
         "mbgl/renderer/query.hpp": "include/mbgl/renderer/query.hpp",
         "mbgl/renderer/renderer.hpp": "include/mbgl/renderer/renderer.hpp",
         "mbgl/renderer/renderer_frontend.hpp": "include/mbgl/renderer/renderer_frontend.hpp",
diff --git a/src/mbgl/util/thread_pool.cpp b/src/mbgl/util/thread_pool.cpp
index 79c2f7501..e839d1b4b 100644
--- a/src/mbgl/util/thread_pool.cpp
+++ b/src/mbgl/util/thread_pool.cpp
@@ -2,6 +2,7 @@
 
 #include <mbgl/util/platform.hpp>
 #include <mbgl/util/string.hpp>
+#include <mbgl/platform/thread.hpp>
 
 namespace mbgl {
 
@@ -11,6 +12,7 @@ ThreadPool::ThreadPool(std::size_t count) {
     for (std::size_t i = 0; i < count; ++i) {
         threads.emplace_back([this, i]() {
             platform::setCurrentThreadName(std::string{ "Worker " } + util::toString(i + 1));
+            platform::attachThread();
 
             while (true) {
                 std::unique_lock<std::mutex> lock(mutex);
@@ -20,6 +22,7 @@ ThreadPool::ThreadPool(std::size_t count) {
                 });
 
                 if (terminate) {
+                    platform::detachThread();
                     return;
                 }