mirror of
https://github.com/apple/swift.git
synced 2025-12-14 20:36:38 +01:00
f5bdb858e0
Moved all the threading code to one place. Added explicit support for Darwin, Linux, Pthreads, C11 threads and Win32 threads, including new implementations of Once for Linux, Pthreads, C11 and Win32. rdar://90776105
83 lines
2.3 KiB
C++
83 lines
2.3 KiB
C++
//==--- Pthreads.cpp - Threading abstraction implementation ---- -*-C++ -*-===//
|
|
//
|
|
// This source file is part of the Swift.org open source project
|
|
//
|
|
// Copyright (c) 2022 Apple Inc. and the Swift project authors
|
|
// Licensed under Apache License v2.0 with Runtime Library Exception
|
|
//
|
|
// See https://swift.org/LICENSE.txt for license information
|
|
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// Implements threading support for plain pthreads
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#if SWIFT_THREADING_PTHREADS
|
|
|
|
#include "swift/Threading/Errors.h"
|
|
#include "swift/Threading/Impl/Pthreads.h"
|
|
|
|
namespace {
|
|
|
|
#pragma clang diagnostic push
|
|
#pragma GCC diagnostic ignored "-Wglobal-constructors"
|
|
|
|
class MainThreadRememberer {
|
|
private:
|
|
pthread_t mainThread_;
|
|
public:
|
|
MainThreadRememberer() { mainThread_ = pthread_self(); }
|
|
|
|
pthread_t main_thread() const { return mainThread_; }
|
|
};
|
|
|
|
MainThreadRememberer rememberer;
|
|
pthread_mutex_t onceMutex = PTHREAD_MUTEX_INITIALIZER;
|
|
pthread_cond_t onceCond = PTHREAD_COND_INITIALIZER;
|
|
|
|
#pragma clang diagnostic pop
|
|
|
|
}
|
|
|
|
using namespace swift;
|
|
using namespace threading_impl;
|
|
|
|
thread_id
|
|
swift::threading_impl::thread_get_main() {
|
|
return rememberer.main_thread();
|
|
}
|
|
|
|
bool
|
|
swift::threading_impl::thread_is_main() {
|
|
return pthread_equal(pthread_self(), thread_get_main());
|
|
}
|
|
|
|
void
|
|
swift::threading_impl::once_slow(once_t &predicate,
|
|
void (*fn)(void *),
|
|
void *context) {
|
|
std::int64_t zero = 0;
|
|
if (predicate.compare_exchange_strong(zero, (std::int64_t)1,
|
|
std::memory_order_relaxed,
|
|
std::memory_order_relaxed)) {
|
|
fn(context);
|
|
|
|
predicate.store((std::int64_t)-1, std::memory_order_release);
|
|
|
|
pthread_mutex_lock(&onceMutex);
|
|
pthread_mutex_unlock(&onceMutex);
|
|
pthread_cond_broadcast(&onceCond);
|
|
return;
|
|
}
|
|
|
|
pthread_mutex_lock(&onceMutex);
|
|
while (predicate.load(std::memory_order_acquire) >= (std::int64_t)0) {
|
|
pthread_cond_wait(&onceCond);
|
|
}
|
|
pthread_mutex_unlock(&onceMutex);
|
|
}
|
|
|
|
#endif // SWIFT_THREADING_PTHREADS
|