Merge Chromium + Blink git repositories
[chromium-blink-merge.git] / base / threading / platform_thread_linux.cc
blob48cf7443f7d5156b31624318bc0a18d2aba35e5c
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.
5 #include "base/threading/platform_thread.h"
7 #include <errno.h>
8 #include <sched.h>
10 #include "base/lazy_instance.h"
11 #include "base/logging.h"
12 #include "base/threading/platform_thread_internal_posix.h"
13 #include "base/threading/thread_id_name_manager.h"
14 #include "base/tracked_objects.h"
16 #if !defined(OS_NACL)
17 #include <pthread.h>
18 #include <sys/prctl.h>
19 #include <sys/types.h>
20 #include <unistd.h>
21 #endif
23 namespace base {
25 namespace internal {
27 namespace {
28 #if !defined(OS_NACL)
29 const struct sched_param kRealTimePrio = {8};
30 const struct sched_param kResetPrio = {0};
31 #endif
32 } // namespace
34 const ThreadPriorityToNiceValuePair kThreadPriorityToNiceValueMap[4] = {
35 {ThreadPriority::BACKGROUND, 10},
36 {ThreadPriority::NORMAL, 0},
37 {ThreadPriority::DISPLAY, -6},
38 {ThreadPriority::REALTIME_AUDIO, -10},
41 bool SetCurrentThreadPriorityForPlatform(ThreadPriority priority) {
42 #if !defined(OS_NACL)
43 ThreadPriority current_priority;
44 if (priority != ThreadPriority::REALTIME_AUDIO &&
45 GetCurrentThreadPriorityForPlatform(&current_priority) &&
46 current_priority == ThreadPriority::REALTIME_AUDIO) {
47 // If the pthread's round-robin scheduler is already enabled, and the new
48 // priority will use setpriority() instead, the pthread scheduler should be
49 // reset to use SCHED_OTHER so that setpriority() just works.
50 pthread_setschedparam(pthread_self(), SCHED_OTHER, &kResetPrio);
51 return false;
53 return priority == ThreadPriority::REALTIME_AUDIO &&
54 pthread_setschedparam(pthread_self(), SCHED_RR, &kRealTimePrio) == 0;
55 #else
56 return false;
57 #endif
60 bool GetCurrentThreadPriorityForPlatform(ThreadPriority* priority) {
61 #if !defined(OS_NACL)
62 int maybe_sched_rr = 0;
63 struct sched_param maybe_realtime_prio = {0};
64 if (pthread_getschedparam(pthread_self(), &maybe_sched_rr,
65 &maybe_realtime_prio) == 0 &&
66 maybe_sched_rr == SCHED_RR &&
67 maybe_realtime_prio.sched_priority == kRealTimePrio.sched_priority) {
68 *priority = ThreadPriority::REALTIME_AUDIO;
69 return true;
71 #endif
72 return false;
75 } // namespace internal
77 // static
78 void PlatformThread::SetName(const std::string& name) {
79 ThreadIdNameManager::GetInstance()->SetName(CurrentId(), name);
80 tracked_objects::ThreadData::InitializeThreadContext(name);
82 #if !defined(OS_NACL)
83 // On linux we can get the thread names to show up in the debugger by setting
84 // the process name for the LWP. We don't want to do this for the main
85 // thread because that would rename the process, causing tools like killall
86 // to stop working.
87 if (PlatformThread::CurrentId() == getpid())
88 return;
90 // http://0pointer.de/blog/projects/name-your-threads.html
91 // Set the name for the LWP (which gets truncated to 15 characters).
92 // Note that glibc also has a 'pthread_setname_np' api, but it may not be
93 // available everywhere and it's only benefit over using prctl directly is
94 // that it can set the name of threads other than the current thread.
95 int err = prctl(PR_SET_NAME, name.c_str());
96 // We expect EPERM failures in sandboxed processes, just ignore those.
97 if (err < 0 && errno != EPERM)
98 DPLOG(ERROR) << "prctl(PR_SET_NAME)";
99 #endif // !defined(OS_NACL)
102 void InitThreading() {}
104 void InitOnThread() {}
106 void TerminateOnThread() {}
108 size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes) {
109 #if !defined(THREAD_SANITIZER)
110 return 0;
111 #else
112 // ThreadSanitizer bloats the stack heavily. Evidence has been that the
113 // default stack size isn't enough for some browser tests.
114 return 2 * (1 << 23); // 2 times 8192K (the default stack size on Linux).
115 #endif
118 } // namespace base