base/threading/platform_thread_linux.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 <sched.h>
   9
  10 #include "base/lazy_instance.h"
  11 #include "base/logging.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/safe_strerror_posix.h"
  14 #include "base/threading/thread_id_name_manager.h"
  15 #include "base/threading/thread_restrictions.h"
  16 #include "base/tracked_objects.h"
  17
  18 #if !defined(OS_NACL)
  19 #include <sys/prctl.h>
  20 #include <sys/resource.h>
  21 #include <sys/syscall.h>
  22 #include <sys/time.h>
  23 #include <unistd.h>
  24 #endif
  25
  26 namespace base {
  27
  28 namespace {
  29 int ThreadNiceValue(ThreadPriority priority) {
  30   switch (priority) {
  31     case kThreadPriority_RealtimeAudio:
  32       return -10;
  33     case kThreadPriority_Background:
  34       return 10;
  35     case kThreadPriority_Normal:
  36       return 0;
  37     case kThreadPriority_Display:
  38       return -6;
  39     default:
  40       NOTREACHED() << "Unknown priority.";
  41       return 0;
  42   }
  43 }
  44 } // namespace
  45
  46 // static
  47 void PlatformThread::SetName(const char* name) {
  48   ThreadIdNameManager::GetInstance()->SetName(CurrentId(), name);
  49   tracked_objects::ThreadData::InitializeThreadContext(name);
  50
  51 #if !defined(OS_NACL)
  52   // On linux we can get the thread names to show up in the debugger by setting
  53   // the process name for the LWP.  We don't want to do this for the main
  54   // thread because that would rename the process, causing tools like killall
  55   // to stop working.
  56   if (PlatformThread::CurrentId() == getpid())
  57     return;
  58
  59   // http://0pointer.de/blog/projects/name-your-threads.html
  60   // Set the name for the LWP (which gets truncated to 15 characters).
  61   // Note that glibc also has a 'pthread_setname_np' api, but it may not be
  62   // available everywhere and it's only benefit over using prctl directly is
  63   // that it can set the name of threads other than the current thread.
  64   int err = prctl(PR_SET_NAME, name);
  65   // We expect EPERM failures in sandboxed processes, just ignore those.
  66   if (err < 0 && errno != EPERM)
  67     DPLOG(ERROR) << "prctl(PR_SET_NAME)";
  68 #endif  //  !defined(OS_NACL)
  69 }
  70
  71 // static
  72 void PlatformThread::SetThreadPriority(PlatformThreadHandle handle,
  73                                        ThreadPriority priority) {
  74 #if !defined(OS_NACL)
  75   if (priority == kThreadPriority_RealtimeAudio) {
  76     const struct sched_param kRealTimePrio = { 8 };
  77     if (pthread_setschedparam(pthread_self(), SCHED_RR, &kRealTimePrio) == 0) {
  78       // Got real time priority, no need to set nice level.
  79       return;
  80     }
  81   }
  82
  83   // setpriority(2) will set a thread's priority if it is passed a tid as
  84   // the 'process identifier', not affecting the rest of the threads in the
  85   // process. Setting this priority will only succeed if the user has been
  86   // granted permission to adjust nice values on the system.
  87   DCHECK_NE(handle.id_, kInvalidThreadId);
  88   const int kNiceSetting = ThreadNiceValue(priority);
  89   if (setpriority(PRIO_PROCESS, handle.id_, kNiceSetting)) {
  90     DVPLOG(1) << "Failed to set nice value of thread ("
  91               << handle.id_ << ") to " << kNiceSetting;
  92   }
  93 #endif  //  !defined(OS_NACL)
  94 }
  95
  96 void InitThreading() {}
  97
  98 void InitOnThread() {}
  99
 100 void TerminateOnThread() {}
 101
 102 size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes) {
 103 #if !defined(THREAD_SANITIZER) && !defined(MEMORY_SANITIZER)
 104   return 0;
 105 #else
 106   // ThreadSanitizer bloats the stack heavily. Evidence has been that the
 107   // default stack size isn't enough for some browser tests.
 108   // MemorySanitizer needs this as a temporary fix for http://crbug.com/353687
 109   return 2 * (1 << 23);  // 2 times 8192K (the default stack size on Linux).
 110 #endif
 111 }
 112
 113 }  // namespace base