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 #include <stddef.h>
10
11 #include "base/lazy_instance.h"
12 #include "base/logging.h"
13 #include "base/threading/platform_thread_internal_posix.h"
14 #include "base/threading/thread_id_name_manager.h"
15 #include "base/tracked_objects.h"
16 #include "build/build_config.h"
17
18 #if !defined(OS_NACL)
19 #include <pthread.h>
20 #include <sys/prctl.h>
21 #include <sys/types.h>
22 #include <unistd.h>
23 #endif
24
25 namespace base {
26
27 namespace internal {
28
29 namespace {
30 #if !defined(OS_NACL)
31 const struct sched_param kRealTimePrio = {8};
32 #endif
33 } // namespace
34
35 const ThreadPriorityToNiceValuePair kThreadPriorityToNiceValueMap[4] = {
36 {ThreadPriority::BACKGROUND, 10},
37 {ThreadPriority::NORMAL, 0},
38 {ThreadPriority::DISPLAY, -8},
39 {ThreadPriority::REALTIME_AUDIO, -10},
40 };
41
SetCurrentThreadPriorityForPlatform(ThreadPriority priority)42 bool SetCurrentThreadPriorityForPlatform(ThreadPriority priority) {
43 #if !defined(OS_NACL)
44 return priority == ThreadPriority::REALTIME_AUDIO &&
45 pthread_setschedparam(pthread_self(), SCHED_RR, &kRealTimePrio) == 0;
46 #else
47 return false;
48 #endif
49 }
50
GetCurrentThreadPriorityForPlatform(ThreadPriority * priority)51 bool GetCurrentThreadPriorityForPlatform(ThreadPriority* priority) {
52 #if !defined(OS_NACL)
53 int maybe_sched_rr = 0;
54 struct sched_param maybe_realtime_prio = {0};
55 if (pthread_getschedparam(pthread_self(), &maybe_sched_rr,
56 &maybe_realtime_prio) == 0 &&
57 maybe_sched_rr == SCHED_RR &&
58 maybe_realtime_prio.sched_priority == kRealTimePrio.sched_priority) {
59 *priority = ThreadPriority::REALTIME_AUDIO;
60 return true;
61 }
62 #endif
63 return false;
64 }
65
66 } // namespace internal
67
68 // static
SetName(const std::string & name)69 void PlatformThread::SetName(const std::string& name) {
70 ThreadIdNameManager::GetInstance()->SetName(CurrentId(), name);
71 tracked_objects::ThreadData::InitializeThreadContext(name);
72
73 #if !defined(OS_NACL)
74 // On linux we can get the thread names to show up in the debugger by setting
75 // the process name for the LWP. We don't want to do this for the main
76 // thread because that would rename the process, causing tools like killall
77 // to stop working.
78 if (PlatformThread::CurrentId() == getpid())
79 return;
80
81 // http://0pointer.de/blog/projects/name-your-threads.html
82 // Set the name for the LWP (which gets truncated to 15 characters).
83 // Note that glibc also has a 'pthread_setname_np' api, but it may not be
84 // available everywhere and it's only benefit over using prctl directly is
85 // that it can set the name of threads other than the current thread.
86 int err = prctl(PR_SET_NAME, name.c_str());
87 // We expect EPERM failures in sandboxed processes, just ignore those.
88 if (err < 0 && errno != EPERM)
89 DPLOG(ERROR) << "prctl(PR_SET_NAME)";
90 #endif // !defined(OS_NACL)
91 }
92
InitThreading()93 void InitThreading() {}
94
TerminateOnThread()95 void TerminateOnThread() {}
96
GetDefaultThreadStackSize(const pthread_attr_t &)97 size_t GetDefaultThreadStackSize(const pthread_attr_t& /*attributes*/) {
98 #if !defined(THREAD_SANITIZER)
99 return 0;
100 #else
101 // ThreadSanitizer bloats the stack heavily. Evidence has been that the
102 // default stack size isn't enough for some browser tests.
103 return 2 * (1 << 23); // 2 times 8192K (the default stack size on Linux).
104 #endif
105 }
106
107 } // namespace base
108