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 static const int threadPriorityAudio = -10; 31 static const int threadPriorityBackground = 10; 32 static const int threadPriorityDefault = 0; 33 static const int threadPriorityDisplay = -6; 34 switch (priority) { 35 case kThreadPriority_RealtimeAudio: 36 return threadPriorityAudio; 37 case kThreadPriority_Background: 38 return threadPriorityBackground; 39 case kThreadPriority_Normal: 40 return threadPriorityDefault; 41 case kThreadPriority_Display: 42 return threadPriorityDisplay; 43 default: 44 NOTREACHED() << "Unknown priority."; 45 return 0; 46 } 47 } 48 } // namespace 49 50 // static 51 void PlatformThread::SetName(const char* name) { 52 ThreadIdNameManager::GetInstance()->SetName(CurrentId(), name); 53 tracked_objects::ThreadData::InitializeThreadContext(name); 54 55 #ifndef OS_NACL 56 // On linux we can get the thread names to show up in the debugger by setting 57 // the process name for the LWP. We don't want to do this for the main 58 // thread because that would rename the process, causing tools like killall 59 // to stop working. 60 if (PlatformThread::CurrentId() == getpid()) 61 return; 62 63 // http://0pointer.de/blog/projects/name-your-threads.html 64 // Set the name for the LWP (which gets truncated to 15 characters). 65 // Note that glibc also has a 'pthread_setname_np' api, but it may not be 66 // available everywhere and it's only benefit over using prctl directly is 67 // that it can set the name of threads other than the current thread. 68 int err = prctl(PR_SET_NAME, name); 69 // We expect EPERM failures in sandboxed processes, just ignore those. 70 if (err < 0 && errno != EPERM) 71 DPLOG(ERROR) << "prctl(PR_SET_NAME)"; 72 #endif 73 } 74 75 // static 76 void PlatformThread::SetThreadPriority(PlatformThreadHandle handle, 77 ThreadPriority priority) { 78 #if !defined(OS_NACL) 79 if (priority == kThreadPriority_RealtimeAudio) { 80 const int kRealTimePrio = 8; 81 82 struct sched_param sched_param; 83 memset(&sched_param, 0, sizeof(sched_param)); 84 sched_param.sched_priority = kRealTimePrio; 85 86 if (pthread_setschedparam(pthread_self(), SCHED_RR, &sched_param) == 0) { 87 // Got real time priority, no need to set nice level. 88 return; 89 } 90 } 91 92 // setpriority(2) will set a thread's priority if it is passed a tid as 93 // the 'process identifier', not affecting the rest of the threads in the 94 // process. Setting this priority will only succeed if the user has been 95 // granted permission to adjust nice values on the system. 96 DCHECK_NE(handle.id_, kInvalidThreadId); 97 int kNiceSetting = ThreadNiceValue(priority); 98 if (setpriority(PRIO_PROCESS, handle.id_, kNiceSetting)) 99 LOG(ERROR) << "Failed to set nice value of thread to " << kNiceSetting; 100 #endif // !OS_NACL 101 } 102 103 void InitThreading() { 104 } 105 106 void InitOnThread() { 107 } 108 109 void TerminateOnThread() { 110 } 111 112 size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes) { 113 return 0; 114 } 115 116 } // namespace base 117