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 =
 104       pthread_create(&handle, &attributes, ThreadFunc, params.get());
 105   bool success = !err;
 106   if (success) {
 107     // ThreadParams should be deleted on the created thread after used.
 108     ignore_result(params.release());
 109   } else {
 110     // Value of |handle| is undefined if pthread_create fails.
 111     handle = 0;
 112     errno = err;
 113     PLOG(ERROR) << "pthread_create";
 114   }
 115   *thread_handle = PlatformThreadHandle(handle);
 116
 117   pthread_attr_destroy(&attributes);
 118
 119   return success;
 120 }
 121
 122 }  // namespace
 123
 124 // static
 125 PlatformThreadId PlatformThread::CurrentId() {
 126   // Pthreads doesn't have the concept of a thread ID, so we have to reach down
 127   // into the kernel.
 128 #if defined(OS_MACOSX)
 129   return pthread_mach_thread_np(pthread_self());
 130 #elif defined(OS_LINUX)
 131   return syscall(__NR_gettid);
 132 #elif defined(OS_ANDROID)
 133   return gettid();
 134 #elif defined(OS_SOLARIS) || defined(OS_QNX)
 135   return pthread_self();
 136 #elif defined(OS_NACL) && defined(__GLIBC__)
 137   return pthread_self();
 138 #elif defined(OS_NACL) && !defined(__GLIBC__)
 139   // Pointers are 32-bits in NaCl.
 140   return reinterpret_cast<int32>(pthread_self());
 141 #elif defined(OS_POSIX)
 142   return reinterpret_cast<int64>(pthread_self());
 143 #endif
 144 }
 145
 146 // static
 147 PlatformThreadRef PlatformThread::CurrentRef() {
 148   return PlatformThreadRef(pthread_self());
 149 }
 150
 151 // static
 152 PlatformThreadHandle PlatformThread::CurrentHandle() {
 153   return PlatformThreadHandle(pthread_self());
 154 }
 155
 156 // static
 157 void PlatformThread::YieldCurrentThread() {
 158   sched_yield();
 159 }
 160
 161 // static
 162 void PlatformThread::Sleep(TimeDelta duration) {
 163   struct timespec sleep_time, remaining;
 164
 165   // Break the duration into seconds and nanoseconds.
 166   // NOTE: TimeDelta's microseconds are int64s while timespec's
 167   // nanoseconds are longs, so this unpacking must prevent overflow.
 168   sleep_time.tv_sec = duration.InSeconds();
 169   duration -= TimeDelta::FromSeconds(sleep_time.tv_sec);
 170   sleep_time.tv_nsec = duration.InMicroseconds() * 1000;  // nanoseconds
 171
 172   while (nanosleep(&sleep_time, &remaining) == -1 && errno == EINTR)
 173     sleep_time = remaining;
 174 }
 175
 176 // static
 177 const char* PlatformThread::GetName() {
 178   return ThreadIdNameManager::GetInstance()->GetName(CurrentId());
 179 }
 180
 181 // static
 182 bool PlatformThread::CreateWithPriority(size_t stack_size, Delegate* delegate,
 183                                         PlatformThreadHandle* thread_handle,
 184                                         ThreadPriority priority) {
 185   return CreateThread(stack_size, true,  // joinable thread
 186                       delegate, thread_handle, priority);
 187 }
 188
 189 // static
 190 bool PlatformThread::CreateNonJoinable(size_t stack_size, Delegate* delegate) {
 191   PlatformThreadHandle unused;
 192
 193   bool result = CreateThread(stack_size, false /* non-joinable thread */,
 194                              delegate, &unused, ThreadPriority::NORMAL);
 195   return result;
 196 }
 197
 198 // static
 199 void PlatformThread::Join(PlatformThreadHandle thread_handle) {
 200   // Joining another thread may block the current thread for a long time, since
 201   // the thread referred to by |thread_handle| may still be running long-lived /
 202   // blocking tasks.
 203   base::ThreadRestrictions::AssertIOAllowed();
 204   CHECK_EQ(0, pthread_join(thread_handle.platform_handle(), NULL));
 205 }
 206
 207 // Mac has its own Set/GetCurrentThreadPriority() implementations.
 208 #if !defined(OS_MACOSX)
 209
 210 // static
 211 void PlatformThread::SetCurrentThreadPriority(ThreadPriority priority) {
 212 #if defined(OS_NACL)
 213   NOTIMPLEMENTED();
 214 #else
 215   if (internal::SetCurrentThreadPriorityForPlatform(priority))
 216     return;
 217
 218   // setpriority(2) should change the whole thread group's (i.e. process)
 219   // priority. However, as stated in the bugs section of
 220   // http://man7.org/linux/man-pages/man2/getpriority.2.html: "under the current
 221   // Linux/NPTL implementation of POSIX threads, the nice value is a per-thread
 222   // attribute". Also, 0 is prefered to the current thread id since it is
 223   // equivalent but makes sandboxing easier (https://crbug.com/399473).
 224   const int nice_setting = internal::ThreadPriorityToNiceValue(priority);
 225   if (setpriority(PRIO_PROCESS, 0, nice_setting)) {
 226     DVPLOG(1) << "Failed to set nice value of thread ("
 227               << PlatformThread::CurrentId() << ") to " << nice_setting;
 228   }
 229 #endif  // defined(OS_NACL)
 230 }
 231
 232 // static
 233 ThreadPriority PlatformThread::GetCurrentThreadPriority() {
 234 #if defined(OS_NACL)
 235   NOTIMPLEMENTED();
 236   return ThreadPriority::NORMAL;
 237 #else
 238   // Mirrors SetCurrentThreadPriority()'s implementation.
 239   ThreadPriority platform_specific_priority;
 240   if (internal::GetCurrentThreadPriorityForPlatform(
 241           &platform_specific_priority)) {
 242     return platform_specific_priority;
 243   }
 244
 245   // Need to clear errno before calling getpriority():
 246   // http://man7.org/linux/man-pages/man2/getpriority.2.html
 247   errno = 0;
 248   int nice_value = getpriority(PRIO_PROCESS, 0);
 249   if (errno != 0) {
 250     DVPLOG(1) << "Failed to get nice value of thread ("
 251               << PlatformThread::CurrentId() << ")";
 252     return ThreadPriority::NORMAL;
 253   }
 254
 255   return internal::NiceValueToThreadPriority(nice_value);
 256 #endif  // !defined(OS_NACL)
 257 }
 258
 259 #endif  // !defined(OS_MACOSX)
 260
 261 }  // namespace base