[Threading] Android thread naming and other cleanup

src/xenia/base/platform_android.cc

@@ -35,16 +35,20 @@ void Initialize(const ANativeActivity* activity) {
   AConfiguration_delete(configuration);
 
   if (api_level_ >= 26) {
-    // Leaked intentionally, already loaded into the address space.
+    // Leaked intentionally as these will be usable anywhere, already loaded
+    // into the address space as the application is linked against them.
     // https://chromium.googlesource.com/chromium/src/+/master/third_party/ashmem/ashmem-dev.c#201
     void* libandroid = dlopen("libandroid.so", RTLD_NOW);
     assert_not_null(libandroid);
-#define XE_PLATFORM_ANDROID_LOAD_API_FUNCTION(name, api)         \
+    void* libc = dlopen("libc.so", RTLD_NOW);
+    assert_not_null(libc);
+#define XE_PLATFORM_ANDROID_LOAD_API_FUNCTION(lib, name, api)    \
   api_functions_.api_##api.name =                                \
       reinterpret_cast<decltype(api_functions_.api_##api.name)>( \
-          dlsym(libandroid, #name));                             \
+          dlsym(lib, #name));                                    \
   assert_not_null(api_functions_.api_##api.name);
-    XE_PLATFORM_ANDROID_LOAD_API_FUNCTION(ASharedMemory_create, 26);
+    XE_PLATFORM_ANDROID_LOAD_API_FUNCTION(libandroid, ASharedMemory_create, 26);
+    XE_PLATFORM_ANDROID_LOAD_API_FUNCTION(libc, pthread_getname_np, 26);
 #undef XE_PLATFORM_ANDROID_LOAD_API_FUNCTION
   }
 

src/xenia/base/platform_android.h

@@ -15,6 +15,7 @@
 // avoided!
 
 #include <android/native_activity.h>
+#include <pthread.h>
 #include <cstddef>
 #include <cstdint>
 
@@ -32,7 +33,10 @@ int32_t api_level();
 // Android API functions added after the minimum supported API version.
 struct ApiFunctions {
   struct {
+    // libandroid
     int (*ASharedMemory_create)(const char* name, size_t size);
+    // libc
+    int (*pthread_getname_np)(pthread_t pthread, char* buf, size_t n);
   } api_26;
 };
 const ApiFunctions& api_functions();

src/xenia/base/threading.h

@@ -95,9 +95,6 @@ void set_current_thread_id(uint32_t id);
 
 // Sets the current thread name.
 void set_name(const std::string_view name);
-// Sets the target thread name.
-void set_name(std::thread::native_handle_type handle,
-              const std::string_view name);
 
 // Yields the current thread to the scheduler. Maybe.
 void MaybeYield();

src/xenia/base/threading_linux.cc

@@ -1,17 +0,0 @@
-/**
- ******************************************************************************
- * Xenia : Xbox 360 Emulator Research Project                                 *
- ******************************************************************************
- * Copyright 2015 Ben Vanik. All rights reserved.                             *
- * Released under the BSD license - see LICENSE in the root for more details. *
- ******************************************************************************
- */
-
-#include "xenia/base/threading.h"
-
-#include <pthread.h>
-#include <time.h>
-
-namespace xe {
-namespace threading {}  // namespace threading
-}  // namespace xe

src/xenia/base/threading_mac.cc

@@ -26,10 +26,6 @@ uint32_t current_thread_id() {
 
 void set_name(const std::string& name) { pthread_setname_np(name.c_str()); }
 
-void set_name(std::thread::native_handle_type handle, const std::string& name) {
-  // ?
-}
-
 void MaybeYield() { pthread_yield_np(); }
 
 void Sleep(std::chrono::microseconds duration) {

src/xenia/base/threading_posix.cc

@@ -21,11 +21,15 @@
 #include <sys/types.h>
 #include <unistd.h>
 #include <array>
+#include <cstring>
 #include <ctime>
 #include <memory>
 
 #if XE_PLATFORM_ANDROID
 #include <sched.h>
+
+#include "xenia/base/platform_android.h"
+#include "xenia/base/string_util.h"
 #endif
 
 namespace xe {
@@ -92,13 +96,6 @@ uint32_t current_thread_system_id() {
   return static_cast<uint32_t>(syscall(SYS_gettid));
 }
 
-void set_name(std::thread::native_handle_type handle,
-              const std::string_view name) {
-  pthread_setname_np(handle, std::string(name).c_str());
-}
-
-void set_name(const std::string_view name) { set_name(pthread_self(), name); }
-
 void MaybeYield() {
 #if XE_PLATFORM_ANDROID
   sched_yield();
@@ -498,7 +495,11 @@ class PosixCondition<Thread> : public PosixConditionBase {
         signaled_(false),
         exit_code_(0),
         state_(State::kUninitialized),
-        suspend_count_(0) {}
+        suspend_count_(0) {
+#if XE_PLATFORM_ANDROID
+    android_pre_api_26_name_[0] = '\0';
+#endif
+  }
   bool Initialize(Thread::CreationParameters params,
                   ThreadStartData* start_data) {
     start_data->create_suspended = params.create_suspended;
@@ -534,7 +535,11 @@ class PosixCondition<Thread> : public PosixConditionBase {
       : thread_(thread),
         signaled_(false),
         exit_code_(0),
-        state_(State::kRunning) {}
+        state_(State::kRunning) {
+#if XE_PLATFORM_ANDROID
+    android_pre_api_26_name_[0] = '\0';
+#endif
+  }
 
   virtual ~PosixCondition() {
     if (thread_ && !signaled_) {
@@ -561,9 +566,25 @@ class PosixCondition<Thread> : public PosixConditionBase {
     auto result = std::array<char, 17>{'\0'};
     std::unique_lock<std::mutex> lock(state_mutex_);
     if (state_ != State::kUninitialized && state_ != State::kFinished) {
-      if (pthread_getname_np(thread_, result.data(), result.size() - 1) != 0)
+#if XE_PLATFORM_ANDROID
+      // pthread_getname_np was added in API 26 - below that, store the name in
+      // this object, which may be only modified through Xenia threading, but
+      // should be enough in most cases.
+      if (xe::platform::android::api_level() >= 26) {
+        if (xe::platform::android::api_functions().api_26.pthread_getname_np(
+                thread_, result.data(), result.size() - 1) != 0) {
           assert_always();
         }
+      } else {
+        std::lock_guard<std::mutex> lock(android_pre_api_26_name_mutex_);
+        std::strcpy(result.data(), android_pre_api_26_name_);
+      }
+#else
+      if (pthread_getname_np(thread_, result.data(), result.size() - 1) != 0) {
+        assert_always();
+      }
+#endif
+    }
     return std::string(result.data());
   }
 
@@ -571,11 +592,24 @@ class PosixCondition<Thread> : public PosixConditionBase {
     WaitStarted();
     std::unique_lock<std::mutex> lock(state_mutex_);
     if (state_ != State::kUninitialized && state_ != State::kFinished) {
-      threading::set_name(static_cast<std::thread::native_handle_type>(thread_),
-                          name);
+      pthread_setname_np(thread_, std::string(name).c_str());
+#if XE_PLATFORM_ANDROID
+      SetAndroidPreApi26Name(name);
+#endif
     }
   }
 
+#if XE_PLATFORM_ANDROID
+  void SetAndroidPreApi26Name(const std::string_view name) {
+    if (xe::platform::android::api_level() >= 26) {
+      return;
+    }
+    std::lock_guard<std::mutex> lock(android_pre_api_26_name_mutex_);
+    xe::string_util::copy_truncating(android_pre_api_26_name_, name,
+                                     xe::countof(android_pre_api_26_name_));
+  }
+#endif
+
   uint32_t system_id() const { return static_cast<uint32_t>(thread_); }
 
   uint64_t affinity_mask() {
@@ -647,8 +681,13 @@ class PosixCondition<Thread> : public PosixConditionBase {
     user_callback_ = std::move(callback);
     sigval value{};
     value.sival_ptr = this;
+#if XE_PLATFORM_ANDROID
+    sigqueue(pthread_gettid_np(thread_),
+             GetSystemSignal(SignalType::kThreadUserCallback), value);
+#else
     pthread_sigqueue(thread_, GetSystemSignal(SignalType::kThreadUserCallback),
                      value);
+#endif
   }
 
   void CallUserCallback() {
@@ -751,6 +790,12 @@ class PosixCondition<Thread> : public PosixConditionBase {
   mutable std::mutex callback_mutex_;
   mutable std::condition_variable state_signal_;
   std::function<void()> user_callback_;
+#if XE_PLATFORM_ANDROID
+  // Name accessible via name() on Android before API 26 which added
+  // pthread_getname_np.
+  mutable std::mutex android_pre_api_26_name_mutex_;
+  char android_pre_api_26_name_[16];
+#endif
 };
 
 class PosixWaitHandle {
@@ -770,7 +815,7 @@ class PosixConditionHandle : public T, public PosixWaitHandle {
   PosixConditionHandle(uint32_t initial_count, uint32_t maximum_count);
   ~PosixConditionHandle() override = default;
 
-  PosixConditionBase& condition() override { return handle_; }
+  PosixCondition<T>& condition() override { return handle_; }
   void* native_handle() const override { return handle_.native_handle(); }
 
  protected:
@@ -1079,6 +1124,15 @@ void Thread::Exit(int exit_code) {
   }
 }
 
+void set_name(const std::string_view name) {
+  pthread_setname_np(pthread_self(), std::string(name).c_str());
+#if XE_PLATFORM_ANDROID
+  if (xe::platform::android::api_level() < 26 && current_thread_) {
+    current_thread_->condition().SetAndroidPreApi26Name(name);
+  }
+#endif
+}
+
 static void signal_handler(int signal, siginfo_t* info, void* /*context*/) {
   switch (GetSystemSignalType(signal)) {
     case SignalType::kHighResolutionTimer: {

src/xenia/base/threading_win.cc

@@ -57,7 +57,7 @@ void raise_thread_name_exception(HANDLE thread, const std::string& name) {
   }
 }
 
-void set_name(HANDLE thread, const std::string_view name) {
+static void set_name(HANDLE thread, const std::string_view name) {
   auto kernel = GetModuleHandleW(L"kernel32.dll");
   if (kernel) {
     auto func =