diff options
Diffstat (limited to 'security/sandbox/chromium/base/threading/platform_thread_posix.cc')
| -rw-r--r-- | security/sandbox/chromium/base/threading/platform_thread_posix.cc | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/security/sandbox/chromium/base/threading/platform_thread_posix.cc b/security/sandbox/chromium/base/threading/platform_thread_posix.cc new file mode 100644 index 0000000000..335848e329 --- /dev/null +++ b/security/sandbox/chromium/base/threading/platform_thread_posix.cc @@ -0,0 +1,361 @@ +// Copyright (c) 2012 The Chromium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +#include "base/threading/platform_thread.h" + +#include <errno.h> +#include <pthread.h> +#include <sched.h> +#include <stddef.h> +#include <stdint.h> +#include <sys/time.h> +#include <sys/types.h> +#include <unistd.h> + +#include <memory> + +#include "base/debug/activity_tracker.h" +#include "base/lazy_instance.h" +#include "base/logging.h" +#include "base/no_destructor.h" +#include "base/threading/platform_thread_internal_posix.h" +#include "base/threading/scoped_blocking_call.h" +#include "base/threading/thread_id_name_manager.h" +#include "build/build_config.h" + +#if !defined(OS_MACOSX) && !defined(OS_FUCHSIA) && !defined(OS_NACL) +#include "base/posix/can_lower_nice_to.h" +#endif + +#if defined(OS_LINUX) +#include <sys/syscall.h> +#endif + +#if defined(OS_FUCHSIA) +#include <zircon/process.h> +#else +#include <sys/resource.h> +#endif + +namespace base { + +void InitThreading(); +void TerminateOnThread(); +size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes); + +namespace { + +struct ThreadParams { + ThreadParams() + : delegate(nullptr), joinable(false), priority(ThreadPriority::NORMAL) {} + + PlatformThread::Delegate* delegate; + bool joinable; + ThreadPriority priority; +}; + +void* ThreadFunc(void* params) { + PlatformThread::Delegate* delegate = nullptr; + + { + std::unique_ptr<ThreadParams> thread_params( + static_cast<ThreadParams*>(params)); + + delegate = thread_params->delegate; + if (!thread_params->joinable) + base::ThreadRestrictions::SetSingletonAllowed(false); + +#if !defined(OS_NACL) + // Threads on linux/android may inherit their priority from the thread + // where they were created. This explicitly sets the priority of all new + // threads. + PlatformThread::SetCurrentThreadPriority(thread_params->priority); +#endif + } + + ThreadIdNameManager::GetInstance()->RegisterThread( + PlatformThread::CurrentHandle().platform_handle(), + PlatformThread::CurrentId()); + + delegate->ThreadMain(); + + ThreadIdNameManager::GetInstance()->RemoveName( + PlatformThread::CurrentHandle().platform_handle(), + PlatformThread::CurrentId()); + + base::TerminateOnThread(); + return nullptr; +} + +bool CreateThread(size_t stack_size, + bool joinable, + PlatformThread::Delegate* delegate, + PlatformThreadHandle* thread_handle, + ThreadPriority priority) { + DCHECK(thread_handle); + base::InitThreading(); + + pthread_attr_t attributes; + pthread_attr_init(&attributes); + + // Pthreads are joinable by default, so only specify the detached + // attribute if the thread should be non-joinable. + if (!joinable) + pthread_attr_setdetachstate(&attributes, PTHREAD_CREATE_DETACHED); + + // Get a better default if available. + if (stack_size == 0) + stack_size = base::GetDefaultThreadStackSize(attributes); + + if (stack_size > 0) + pthread_attr_setstacksize(&attributes, stack_size); + + std::unique_ptr<ThreadParams> params(new ThreadParams); + params->delegate = delegate; + params->joinable = joinable; + params->priority = priority; + + pthread_t handle; + int err = pthread_create(&handle, &attributes, ThreadFunc, params.get()); + bool success = !err; + if (success) { + // ThreadParams should be deleted on the created thread after used. + ignore_result(params.release()); + } else { + // Value of |handle| is undefined if pthread_create fails. + handle = 0; + errno = err; + PLOG(ERROR) << "pthread_create"; + } + *thread_handle = PlatformThreadHandle(handle); + + pthread_attr_destroy(&attributes); + + return success; +} + +#if defined(OS_LINUX) + +// Store the thread ids in local storage since calling the SWI can +// expensive and PlatformThread::CurrentId is used liberally. Clear +// the stored value after a fork() because forking changes the thread +// id. Forking without going through fork() (e.g. clone()) is not +// supported, but there is no known usage. Using thread_local is +// fine here (despite being banned) since it is going to be allowed +// but is blocked on a clang bug for Mac (https://crbug.com/829078) +// and we can't use ThreadLocalStorage because of re-entrancy due to +// CHECK/DCHECKs. +thread_local pid_t g_thread_id = -1; + +class InitAtFork { + public: + InitAtFork() { pthread_atfork(nullptr, nullptr, internal::ClearTidCache); } +}; + +#endif // defined(OS_LINUX) + +} // namespace + +#if defined(OS_LINUX) + +namespace internal { + +void ClearTidCache() { + g_thread_id = -1; +} + +} // namespace internal + +#endif // defined(OS_LINUX) + +// static +PlatformThreadId PlatformThread::CurrentId() { + // Pthreads doesn't have the concept of a thread ID, so we have to reach down + // into the kernel. +#if defined(OS_MACOSX) + return pthread_mach_thread_np(pthread_self()); +#elif defined(OS_LINUX) + static NoDestructor<InitAtFork> init_at_fork; + if (g_thread_id == -1) { + g_thread_id = syscall(__NR_gettid); + } else { + DCHECK_EQ(g_thread_id, syscall(__NR_gettid)) + << "Thread id stored in TLS is different from thread id returned by " + "the system. It is likely that the process was forked without going " + "through fork()."; + } + return g_thread_id; +#elif defined(OS_ANDROID) + return gettid(); +#elif defined(OS_FUCHSIA) + return zx_thread_self(); +#elif defined(OS_SOLARIS) || defined(OS_QNX) + return pthread_self(); +#elif defined(OS_NACL) && defined(__GLIBC__) + return pthread_self(); +#elif defined(OS_NACL) && !defined(__GLIBC__) + // Pointers are 32-bits in NaCl. + return reinterpret_cast<int32_t>(pthread_self()); +#elif defined(OS_POSIX) && defined(OS_AIX) + return pthread_self(); +#elif defined(OS_POSIX) && !defined(OS_AIX) + return reinterpret_cast<int64_t>(pthread_self()); +#endif +} + +// static +PlatformThreadRef PlatformThread::CurrentRef() { + return PlatformThreadRef(pthread_self()); +} + +// static +PlatformThreadHandle PlatformThread::CurrentHandle() { + return PlatformThreadHandle(pthread_self()); +} + +// static +void PlatformThread::YieldCurrentThread() { + sched_yield(); +} + +// static +void PlatformThread::Sleep(TimeDelta duration) { + struct timespec sleep_time, remaining; + + // Break the duration into seconds and nanoseconds. + // NOTE: TimeDelta's microseconds are int64s while timespec's + // nanoseconds are longs, so this unpacking must prevent overflow. + sleep_time.tv_sec = duration.InSeconds(); + duration -= TimeDelta::FromSeconds(sleep_time.tv_sec); + sleep_time.tv_nsec = duration.InMicroseconds() * 1000; // nanoseconds + + while (nanosleep(&sleep_time, &remaining) == -1 && errno == EINTR) + sleep_time = remaining; +} + +// static +const char* PlatformThread::GetName() { + return ThreadIdNameManager::GetInstance()->GetName(CurrentId()); +} + +// static +bool PlatformThread::CreateWithPriority(size_t stack_size, Delegate* delegate, + PlatformThreadHandle* thread_handle, + ThreadPriority priority) { + return CreateThread(stack_size, true /* joinable thread */, delegate, + thread_handle, priority); +} + +// static +bool PlatformThread::CreateNonJoinable(size_t stack_size, Delegate* delegate) { + return CreateNonJoinableWithPriority(stack_size, delegate, + ThreadPriority::NORMAL); +} + +// static +bool PlatformThread::CreateNonJoinableWithPriority(size_t stack_size, + Delegate* delegate, + ThreadPriority priority) { + PlatformThreadHandle unused; + + bool result = CreateThread(stack_size, false /* non-joinable thread */, + delegate, &unused, priority); + return result; +} + +// static +void PlatformThread::Join(PlatformThreadHandle thread_handle) { + // Record the event that this thread is blocking upon (for hang diagnosis). + base::debug::ScopedThreadJoinActivity thread_activity(&thread_handle); + + // Joining another thread may block the current thread for a long time, since + // the thread referred to by |thread_handle| may still be running long-lived / + // blocking tasks. + base::internal::ScopedBlockingCallWithBaseSyncPrimitives scoped_blocking_call( + FROM_HERE, base::BlockingType::MAY_BLOCK); + CHECK_EQ(0, pthread_join(thread_handle.platform_handle(), nullptr)); +} + +// static +void PlatformThread::Detach(PlatformThreadHandle thread_handle) { + CHECK_EQ(0, pthread_detach(thread_handle.platform_handle())); +} + +// Mac and Fuchsia have their own Set/GetCurrentThreadPriority() +// implementations. +#if !defined(OS_MACOSX) && !defined(OS_FUCHSIA) + +// static +bool PlatformThread::CanIncreaseThreadPriority(ThreadPriority priority) { +#if defined(OS_NACL) + return false; +#else + auto platform_specific_ability = + internal::CanIncreaseCurrentThreadPriorityForPlatform(priority); + if (platform_specific_ability) + return platform_specific_ability.value(); + + return internal::CanLowerNiceTo( + internal::ThreadPriorityToNiceValue(priority)); +#endif // defined(OS_NACL) +} + +// static +void PlatformThread::SetCurrentThreadPriorityImpl(ThreadPriority priority) { +#if defined(OS_NACL) + NOTIMPLEMENTED(); +#else + if (internal::SetCurrentThreadPriorityForPlatform(priority)) + return; + + // setpriority(2) should change the whole thread group's (i.e. process) + // priority. However, as stated in the bugs section of + // http://man7.org/linux/man-pages/man2/getpriority.2.html: "under the current + // Linux/NPTL implementation of POSIX threads, the nice value is a per-thread + // attribute". Also, 0 is prefered to the current thread id since it is + // equivalent but makes sandboxing easier (https://crbug.com/399473). + const int nice_setting = internal::ThreadPriorityToNiceValue(priority); + if (setpriority(PRIO_PROCESS, 0, nice_setting)) { + DVPLOG(1) << "Failed to set nice value of thread (" + << PlatformThread::CurrentId() << ") to " << nice_setting; + } +#endif // defined(OS_NACL) +} + +// static +ThreadPriority PlatformThread::GetCurrentThreadPriority() { +#if defined(OS_NACL) + NOTIMPLEMENTED(); + return ThreadPriority::NORMAL; +#else + // Mirrors SetCurrentThreadPriority()'s implementation. + auto platform_specific_priority = + internal::GetCurrentThreadPriorityForPlatform(); + if (platform_specific_priority) + return platform_specific_priority.value(); + + // Need to clear errno before calling getpriority(): + // http://man7.org/linux/man-pages/man2/getpriority.2.html + errno = 0; + int nice_value = getpriority(PRIO_PROCESS, 0); + if (errno != 0) { + DVPLOG(1) << "Failed to get nice value of thread (" + << PlatformThread::CurrentId() << ")"; + return ThreadPriority::NORMAL; + } + + return internal::NiceValueToThreadPriority(nice_value); +#endif // !defined(OS_NACL) +} + +#endif // !defined(OS_MACOSX) && !defined(OS_FUCHSIA) + +// static +size_t PlatformThread::GetDefaultThreadStackSize() { + pthread_attr_t attributes; + pthread_attr_init(&attributes); + return base::GetDefaultThreadStackSize(attributes); +} + +} // namespace base |