base/threading/platform_thread_posix.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/threading/platform_thread.h"
   6
   7 #include <errno.h>
   8 #include <pthread.h>
   9 #include <sched.h>
  10 #include <sys/resource.h>
  11 #include <sys/time.h>
  12
  13 #include "base/lazy_instance.h"
  14 #include "base/logging.h"
  15 #include "base/memory/scoped_ptr.h"
  16 #include "base/threading/platform_thread_internal_posix.h"
  17 #include "base/threading/thread_id_name_manager.h"
  18 #include "base/threading/thread_restrictions.h"
  19
  20 #if defined(OS_LINUX)
  21 #include <sys/syscall.h>
  22 #elif defined(OS_ANDROID)
  23 #include <sys/types.h>
  24 #endif
  25
  26 namespace base {
  27
  28 void InitThreading();
  29 void InitOnThread();
  30 void TerminateOnThread();
  31 size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes);
  32
  33 namespace {
  34
  35 struct ThreadParams {
  36   ThreadParams()
  37       : delegate(NULL), joinable(false), priority(ThreadPriority::NORMAL) {}
  38
  39   PlatformThread::Delegate* delegate;
  40   bool joinable;
  41   ThreadPriority priority;
  42 };
  43
  44 void* ThreadFunc(void* params) {
  45   base::InitOnThread();
  46
  47   PlatformThread::Delegate* delegate = nullptr;
  48
  49   {
  50     scoped_ptr<ThreadParams> thread_params(static_cast<ThreadParams*>(params));
  51
  52     delegate = thread_params->delegate;
  53     if (!thread_params->joinable)
  54       base::ThreadRestrictions::SetSingletonAllowed(false);
  55
  56     if (thread_params->priority != ThreadPriority::NORMAL)
  57       PlatformThread::SetCurrentThreadPriority(thread_params->priority);
  58   }
  59
  60   ThreadIdNameManager::GetInstance()->RegisterThread(
  61       PlatformThread::CurrentHandle().platform_handle(),
  62       PlatformThread::CurrentId());
  63
  64   delegate->ThreadMain();
  65
  66   ThreadIdNameManager::GetInstance()->RemoveName(
  67       PlatformThread::CurrentHandle().platform_handle(),
  68       PlatformThread::CurrentId());
  69
  70   base::TerminateOnThread();
  71   return NULL;
  72 }
  73
  74 bool CreateThread(size_t stack_size,
  75                   bool joinable,
  76                   PlatformThread::Delegate* delegate,
  77                   PlatformThreadHandle* thread_handle,
  78                   ThreadPriority priority) {
  79   DCHECK(thread_handle);
  80   base::InitThreading();
  81
  82   pthread_attr_t attributes;
  83   pthread_attr_init(&attributes);
  84
  85   // Pthreads are joinable by default, so only specify the detached
  86   // attribute if the thread should be non-joinable.
  87   if (!joinable)
  88     pthread_attr_setdetachstate(&attributes, PTHREAD_CREATE_DETACHED);
  89
  90   // Get a better default if available.
  91   if (stack_size == 0)
  92     stack_size = base::GetDefaultThreadStackSize(attributes);
  93
  94   if (stack_size > 0)
  95     pthread_attr_setstacksize(&attributes, stack_size);
  96
  97   scoped_ptr<ThreadParams> params(new ThreadParams);
  98   params->delegate = delegate;
  99   params->joinable = joinable;
 100   params->priority = priority;
 101
 102   pthread_t handle;
 103   int err = pthread_create(&handle, &attributes, ThreadFunc, params.get());
 104   bool success = !err;
 105   if (success) {
 106     // ThreadParams should be deleted on the created thread after used.
 107     ignore_result(params.release());
 108   } else {
 109     // Value of |handle| is undefined if pthread_create fails.
 110     handle = 0;
 111     errno = err;
 112     PLOG(ERROR) << "pthread_create";
 113   }
 114   *thread_handle = PlatformThreadHandle(handle);
 115
 116   pthread_attr_destroy(&attributes);
 117
 118   return success;
 119 }
 120
 121 }  // namespace
 122
 123 // static
 124 PlatformThreadId PlatformThread::CurrentId() {
 125   // Pthreads doesn't have the concept of a thread ID, so we have to reach down
 126   // into the kernel.
 127 #if defined(OS_MACOSX)
 128   return pthread_mach_thread_np(pthread_self());
 129 #elif defined(OS_LINUX)
 130   return syscall(__NR_gettid);
 131 #elif defined(OS_ANDROID)
 132   return gettid();
 133 #elif defined(OS_SOLARIS) || defined(OS_QNX)
 134   return pthread_self();
 135 #elif defined(OS_NACL) && defined(__GLIBC__)
 136   return pthread_self();
 137 #elif defined(OS_NACL) && !defined(__GLIBC__)
 138   // Pointers are 32-bits in NaCl.
 139   return reinterpret_cast<int32>(pthread_self());
 140 #elif defined(OS_POSIX)
 141   return reinterpret_cast<int64>(pthread_self());
 142 #endif
 143 }
 144
 145 // static
 146 PlatformThreadRef PlatformThread::CurrentRef() {
 147   return PlatformThreadRef(pthread_self());
 148 }
 149
 150 // static
 151 PlatformThreadHandle PlatformThread::CurrentHandle() {
 152   return PlatformThreadHandle(pthread_self());
 153 }
 154
 155 // static
 156 void PlatformThread::YieldCurrentThread() {
 157   sched_yield();
 158 }
 159
 160 // static
 161 void PlatformThread::Sleep(TimeDelta duration) {
 162   struct timespec sleep_time, remaining;
 163
 164   // Break the duration into seconds and nanoseconds.
 165   // NOTE: TimeDelta's microseconds are int64s while timespec's
 166   // nanoseconds are longs, so this unpacking must prevent overflow.
 167   sleep_time.tv_sec = duration.InSeconds();
 168   duration -= TimeDelta::FromSeconds(sleep_time.tv_sec);
 169   sleep_time.tv_nsec = duration.InMicroseconds() * 1000;  // nanoseconds
 170
 171   while (nanosleep(&sleep_time, &remaining) == -1 && errno == EINTR)
 172     sleep_time = remaining;
 173 }
 174
 175 // static
 176 const char* PlatformThread::GetName() {
 177   return ThreadIdNameManager::GetInstance()->GetName(CurrentId());
 178 }
 179
 180 // static
 181 bool PlatformThread::CreateWithPriority(size_t stack_size, Delegate* delegate,
 182                                         PlatformThreadHandle* thread_handle,
 183                                         ThreadPriority priority) {
 184   return CreateThread(stack_size, true,  // joinable thread
 185                       delegate, thread_handle, priority);
 186 }
 187
 188 // static
 189 bool PlatformThread::CreateNonJoinable(size_t stack_size, Delegate* delegate) {
 190   PlatformThreadHandle unused;
 191
 192   bool result = CreateThread(stack_size, false /* non-joinable thread */,
 193                              delegate, &unused, ThreadPriority::NORMAL);
 194   return result;
 195 }
 196
 197 // static
 198 void PlatformThread::Join(PlatformThreadHandle thread_handle) {
 199   // Joining another thread may block the current thread for a long time, since
 200   // the thread referred to by |thread_handle| may still be running long-lived /
 201   // blocking tasks.
 202   base::ThreadRestrictions::AssertIOAllowed();
 203   CHECK_EQ(0, pthread_join(thread_handle.platform_handle(), NULL));
 204 }
 205
 206 // Mac has its own Set/GetCurrentThreadPriority() implementations.
 207 #if !defined(OS_MACOSX)
 208
 209 // static
 210 void PlatformThread::SetCurrentThreadPriority(ThreadPriority priority) {
 211 #if defined(OS_NACL)
 212   NOTIMPLEMENTED();
 213 #else
 214   if (internal::SetCurrentThreadPriorityForPlatform(priority))
 215     return;
 216
 217   // setpriority(2) should change the whole thread group's (i.e. process)
 218   // priority. However, as stated in the bugs section of
 219   // http://man7.org/linux/man-pages/man2/getpriority.2.html: "under the current
 220   // Linux/NPTL implementation of POSIX threads, the nice value is a per-thread
 221   // attribute". Also, 0 is prefered to the current thread id since it is
 222   // equivalent but makes sandboxing easier (https://crbug.com/399473).
 223   const int nice_setting = internal::ThreadPriorityToNiceValue(priority);
 224   if (setpriority(PRIO_PROCESS, 0, nice_setting)) {
 225     DVPLOG(1) << "Failed to set nice value of thread ("
 226               << PlatformThread::CurrentId() << ") to " << nice_setting;
 227   }
 228 #endif  // defined(OS_NACL)
 229 }
 230
 231 // static
 232 ThreadPriority PlatformThread::GetCurrentThreadPriority() {
 233 #if defined(OS_NACL)
 234   NOTIMPLEMENTED();
 235   return ThreadPriority::NORMAL;
 236 #else
 237   // Mirrors SetCurrentThreadPriority()'s implementation.
 238   ThreadPriority platform_specific_priority;
 239   if (internal::GetCurrentThreadPriorityForPlatform(
 240           &platform_specific_priority)) {
 241     return platform_specific_priority;
 242   }
 243
 244   // Need to clear errno before calling getpriority():
 245   // http://man7.org/linux/man-pages/man2/getpriority.2.html
 246   errno = 0;
 247   int nice_value = getpriority(PRIO_PROCESS, 0);
 248   if (errno != 0) {
 249     DVPLOG(1) << "Failed to get nice value of thread ("
 250               << PlatformThread::CurrentId() << ")";
 251     return ThreadPriority::NORMAL;
 252   }
 253
 254   return internal::NiceValueToThreadPriority(nice_value);
 255 #endif  // !defined(OS_NACL)
 256 }
 257
 258 #endif  // !defined(OS_MACOSX)
 259
 260 }  // namespace base