blob: 286bee95f1299823920ec03175962dbf61e9cba8 [file] [log] [blame]
/*
* Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/base/platform_thread.h"
#include "webrtc/base/checks.h"
#if defined(WEBRTC_LINUX)
#include <sys/prctl.h>
#include <sys/syscall.h>
#endif
namespace rtc {
PlatformThreadId CurrentThreadId() {
PlatformThreadId ret;
#if defined(WEBRTC_WIN)
ret = GetCurrentThreadId();
#elif defined(WEBRTC_POSIX)
#if defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
ret = pthread_mach_thread_np(pthread_self());
#elif defined(WEBRTC_LINUX)
ret = syscall(__NR_gettid);
#elif defined(WEBRTC_ANDROID)
ret = gettid();
#else
// Default implementation for nacl and solaris.
ret = reinterpret_cast<pid_t>(pthread_self());
#endif
#endif // defined(WEBRTC_POSIX)
RTC_DCHECK(ret);
return ret;
}
PlatformThreadRef CurrentThreadRef() {
#if defined(WEBRTC_WIN)
return GetCurrentThreadId();
#elif defined(WEBRTC_POSIX)
return pthread_self();
#endif
}
bool IsThreadRefEqual(const PlatformThreadRef& a, const PlatformThreadRef& b) {
#if defined(WEBRTC_WIN)
return a == b;
#elif defined(WEBRTC_POSIX)
return pthread_equal(a, b);
#endif
}
void SetCurrentThreadName(const char* name) {
#if defined(WEBRTC_WIN)
struct {
DWORD dwType;
LPCSTR szName;
DWORD dwThreadID;
DWORD dwFlags;
} threadname_info = {0x1000, name, static_cast<DWORD>(-1), 0};
__try {
::RaiseException(0x406D1388, 0, sizeof(threadname_info) / sizeof(DWORD),
reinterpret_cast<ULONG_PTR*>(&threadname_info));
} __except (EXCEPTION_EXECUTE_HANDLER) {
}
#elif defined(WEBRTC_LINUX) || defined(WEBRTC_ANDROID)
prctl(PR_SET_NAME, reinterpret_cast<unsigned long>(name));
#elif defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
pthread_setname_np(name);
#endif
}
namespace {
#if defined(WEBRTC_WIN)
void CALLBACK RaiseFlag(ULONG_PTR param) {
*reinterpret_cast<bool*>(param) = true;
}
#else
struct ThreadAttributes {
ThreadAttributes() { pthread_attr_init(&attr); }
~ThreadAttributes() { pthread_attr_destroy(&attr); }
pthread_attr_t* operator&() { return &attr; }
pthread_attr_t attr;
};
#endif // defined(WEBRTC_WIN)
}
PlatformThread::PlatformThread(ThreadRunFunction func,
void* obj,
const char* thread_name)
: run_function_(func),
obj_(obj),
name_(thread_name ? thread_name : "webrtc"),
#if defined(WEBRTC_WIN)
stop_(false),
thread_(NULL),
thread_id_(0) {
#else
stop_event_(false, false),
thread_(0) {
#endif // defined(WEBRTC_WIN)
RTC_DCHECK(func);
RTC_DCHECK(name_.length() < 64);
}
PlatformThread::~PlatformThread() {
RTC_DCHECK(thread_checker_.CalledOnValidThread());
#if defined(WEBRTC_WIN)
RTC_DCHECK(!thread_);
RTC_DCHECK(!thread_id_);
#endif // defined(WEBRTC_WIN)
}
#if defined(WEBRTC_WIN)
DWORD WINAPI PlatformThread::StartThread(void* param) {
static_cast<PlatformThread*>(param)->Run();
return 0;
}
#else
void* PlatformThread::StartThread(void* param) {
static_cast<PlatformThread*>(param)->Run();
return 0;
}
#endif // defined(WEBRTC_WIN)
void PlatformThread::Start() {
RTC_DCHECK(thread_checker_.CalledOnValidThread());
RTC_DCHECK(!thread_) << "Thread already started?";
#if defined(WEBRTC_WIN)
stop_ = false;
// See bug 2902 for background on STACK_SIZE_PARAM_IS_A_RESERVATION.
// Set the reserved stack stack size to 1M, which is the default on Windows
// and Linux.
thread_ = ::CreateThread(NULL, 1024 * 1024, &StartThread, this,
STACK_SIZE_PARAM_IS_A_RESERVATION, &thread_id_);
RTC_CHECK(thread_) << "CreateThread failed";
RTC_DCHECK(thread_id_);
#else
ThreadAttributes attr;
// Set the stack stack size to 1M.
pthread_attr_setstacksize(&attr, 1024 * 1024);
RTC_CHECK_EQ(0, pthread_create(&thread_, &attr, &StartThread, this));
#endif // defined(WEBRTC_WIN)
}
bool PlatformThread::IsRunning() const {
RTC_DCHECK(thread_checker_.CalledOnValidThread());
#if defined(WEBRTC_WIN)
return thread_ != nullptr;
#else
return thread_ != 0;
#endif // defined(WEBRTC_WIN)
}
PlatformThreadRef PlatformThread::GetThreadRef() const {
#if defined(WEBRTC_WIN)
return thread_id_;
#else
return thread_;
#endif // defined(WEBRTC_WIN)
}
void PlatformThread::Stop() {
RTC_DCHECK(thread_checker_.CalledOnValidThread());
if (!IsRunning())
return;
#if defined(WEBRTC_WIN)
// Set stop_ to |true| on the worker thread.
bool queued = QueueAPC(&RaiseFlag, reinterpret_cast<ULONG_PTR>(&stop_));
// Queuing the APC can fail if the thread is being terminated.
RTC_CHECK(queued || GetLastError() == ERROR_GEN_FAILURE);
WaitForSingleObject(thread_, INFINITE);
CloseHandle(thread_);
thread_ = nullptr;
thread_id_ = 0;
#else
stop_event_.Set();
RTC_CHECK_EQ(0, pthread_join(thread_, nullptr));
thread_ = 0;
#endif // defined(WEBRTC_WIN)
}
void PlatformThread::Run() {
if (!name_.empty())
rtc::SetCurrentThreadName(name_.c_str());
do {
// The interface contract of Start/Stop is that for a successful call to
// Start, there should be at least one call to the run function. So we
// call the function before checking |stop_|.
if (!run_function_(obj_))
break;
#if defined(WEBRTC_WIN)
// Alertable sleep to permit RaiseFlag to run and update |stop_|.
SleepEx(0, true);
} while (!stop_);
#else
} while (!stop_event_.Wait(0));
#endif // defined(WEBRTC_WIN)
}
bool PlatformThread::SetPriority(ThreadPriority priority) {
RTC_DCHECK(thread_checker_.CalledOnValidThread());
RTC_DCHECK(IsRunning());
#if defined(WEBRTC_WIN)
return SetThreadPriority(thread_, priority) != FALSE;
#elif defined(__native_client__)
// Setting thread priorities is not supported in NaCl.
return true;
#elif defined(WEBRTC_CHROMIUM_BUILD) && defined(WEBRTC_LINUX)
// TODO(tommi): Switch to the same mechanism as Chromium uses for changing
// thread priorities.
return true;
#else
#ifdef WEBRTC_THREAD_RR
const int policy = SCHED_RR;
#else
const int policy = SCHED_FIFO;
#endif
const int min_prio = sched_get_priority_min(policy);
const int max_prio = sched_get_priority_max(policy);
if (min_prio == -1 || max_prio == -1) {
return false;
}
if (max_prio - min_prio <= 2)
return false;
// Convert webrtc priority to system priorities:
sched_param param;
const int top_prio = max_prio - 1;
const int low_prio = min_prio + 1;
switch (priority) {
case kLowPriority:
param.sched_priority = low_prio;
break;
case kNormalPriority:
// The -1 ensures that the kHighPriority is always greater or equal to
// kNormalPriority.
param.sched_priority = (low_prio + top_prio - 1) / 2;
break;
case kHighPriority:
param.sched_priority = std::max(top_prio - 2, low_prio);
break;
case kHighestPriority:
param.sched_priority = std::max(top_prio - 1, low_prio);
break;
case kRealtimePriority:
param.sched_priority = top_prio;
break;
}
return pthread_setschedparam(thread_, policy, &param) == 0;
#endif // defined(WEBRTC_WIN)
}
#if defined(WEBRTC_WIN)
bool PlatformThread::QueueAPC(PAPCFUNC function, ULONG_PTR data) {
RTC_DCHECK(thread_checker_.CalledOnValidThread());
RTC_DCHECK(IsRunning());
return QueueUserAPC(function, thread_, data) != FALSE;
}
#endif
} // namespace rtc