diff options
Diffstat (limited to 'libs/utils/Threads.cpp')
| -rw-r--r-- | libs/utils/Threads.cpp | 952 |
1 files changed, 0 insertions, 952 deletions
diff --git a/libs/utils/Threads.cpp b/libs/utils/Threads.cpp deleted file mode 100644 index ab207f5..0000000 --- a/libs/utils/Threads.cpp +++ /dev/null @@ -1,952 +0,0 @@ -/* - * Copyright (C) 2007 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -// #define LOG_NDEBUG 0 -#define LOG_TAG "libutils.threads" - -#include <utils/threads.h> -#include <utils/Log.h> - -#include <cutils/sched_policy.h> -#include <cutils/properties.h> - -#include <stdio.h> -#include <stdlib.h> -#include <memory.h> -#include <errno.h> -#include <assert.h> -#include <unistd.h> - -#if defined(HAVE_PTHREADS) -# include <pthread.h> -# include <sched.h> -# include <sys/resource.h> -#ifdef HAVE_ANDROID_OS -# include <bionic_pthread.h> -#endif -#elif defined(HAVE_WIN32_THREADS) -# include <windows.h> -# include <stdint.h> -# include <process.h> -# define HAVE_CREATETHREAD // Cygwin, vs. HAVE__BEGINTHREADEX for MinGW -#endif - -#if defined(HAVE_PRCTL) -#include <sys/prctl.h> -#endif - -/* - * =========================================================================== - * Thread wrappers - * =========================================================================== - */ - -using namespace android; - -// ---------------------------------------------------------------------------- -#if defined(HAVE_PTHREADS) -// ---------------------------------------------------------------------------- - -/* - * Create and run a new thread. - * - * We create it "detached", so it cleans up after itself. - */ - -typedef void* (*android_pthread_entry)(void*); - -static pthread_once_t gDoSchedulingGroupOnce = PTHREAD_ONCE_INIT; -static bool gDoSchedulingGroup = true; - -static void checkDoSchedulingGroup(void) { - char buf[PROPERTY_VALUE_MAX]; - int len = property_get("debug.sys.noschedgroups", buf, ""); - if (len > 0) { - int temp; - if (sscanf(buf, "%d", &temp) == 1) { - gDoSchedulingGroup = temp == 0; - } - } -} - -struct thread_data_t { - thread_func_t entryFunction; - void* userData; - int priority; - char * threadName; - - // we use this trampoline when we need to set the priority with - // nice/setpriority, and name with prctl. - static int trampoline(const thread_data_t* t) { - thread_func_t f = t->entryFunction; - void* u = t->userData; - int prio = t->priority; - char * name = t->threadName; - delete t; - setpriority(PRIO_PROCESS, 0, prio); - pthread_once(&gDoSchedulingGroupOnce, checkDoSchedulingGroup); - if (gDoSchedulingGroup) { - if (prio >= ANDROID_PRIORITY_BACKGROUND) { - set_sched_policy(androidGetTid(), SP_BACKGROUND); - } else { - set_sched_policy(androidGetTid(), SP_FOREGROUND); - } - } - - if (name) { -#if defined(HAVE_PRCTL) - // Mac OS doesn't have this, and we build libutil for the host too - int hasAt = 0; - int hasDot = 0; - char *s = name; - while (*s) { - if (*s == '.') hasDot = 1; - else if (*s == '@') hasAt = 1; - s++; - } - int len = s - name; - if (len < 15 || hasAt || !hasDot) { - s = name; - } else { - s = name + len - 15; - } - prctl(PR_SET_NAME, (unsigned long) s, 0, 0, 0); -#endif - free(name); - } - return f(u); - } -}; - -int androidCreateRawThreadEtc(android_thread_func_t entryFunction, - void *userData, - const char* threadName, - int32_t threadPriority, - size_t threadStackSize, - android_thread_id_t *threadId) -{ - pthread_attr_t attr; - pthread_attr_init(&attr); - pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); - -#ifdef HAVE_ANDROID_OS /* valgrind is rejecting RT-priority create reqs */ - if (threadPriority != PRIORITY_DEFAULT || threadName != NULL) { - // Now that the pthread_t has a method to find the associated - // android_thread_id_t (pid) from pthread_t, it would be possible to avoid - // this trampoline in some cases as the parent could set the properties - // for the child. However, there would be a race condition because the - // child becomes ready immediately, and it doesn't work for the name. - // prctl(PR_SET_NAME) only works for self; prctl(PR_SET_THREAD_NAME) was - // proposed but not yet accepted. - thread_data_t* t = new thread_data_t; - t->priority = threadPriority; - t->threadName = threadName ? strdup(threadName) : NULL; - t->entryFunction = entryFunction; - t->userData = userData; - entryFunction = (android_thread_func_t)&thread_data_t::trampoline; - userData = t; - } -#endif - - if (threadStackSize) { - pthread_attr_setstacksize(&attr, threadStackSize); - } - - errno = 0; - pthread_t thread; - int result = pthread_create(&thread, &attr, - (android_pthread_entry)entryFunction, userData); - pthread_attr_destroy(&attr); - if (result != 0) { - ALOGE("androidCreateRawThreadEtc failed (entry=%p, res=%d, errno=%d)\n" - "(android threadPriority=%d)", - entryFunction, result, errno, threadPriority); - return 0; - } - - // Note that *threadID is directly available to the parent only, as it is - // assigned after the child starts. Use memory barrier / lock if the child - // or other threads also need access. - if (threadId != NULL) { - *threadId = (android_thread_id_t)thread; // XXX: this is not portable - } - return 1; -} - -#ifdef HAVE_ANDROID_OS -static pthread_t android_thread_id_t_to_pthread(android_thread_id_t thread) -{ - return (pthread_t) thread; -} -#endif - -android_thread_id_t androidGetThreadId() -{ - return (android_thread_id_t)pthread_self(); -} - -// ---------------------------------------------------------------------------- -#elif defined(HAVE_WIN32_THREADS) -// ---------------------------------------------------------------------------- - -/* - * Trampoline to make us __stdcall-compliant. - * - * We're expected to delete "vDetails" when we're done. - */ -struct threadDetails { - int (*func)(void*); - void* arg; -}; -static __stdcall unsigned int threadIntermediary(void* vDetails) -{ - struct threadDetails* pDetails = (struct threadDetails*) vDetails; - int result; - - result = (*(pDetails->func))(pDetails->arg); - - delete pDetails; - - ALOG(LOG_VERBOSE, "thread", "thread exiting\n"); - return (unsigned int) result; -} - -/* - * Create and run a new thread. - */ -static bool doCreateThread(android_thread_func_t fn, void* arg, android_thread_id_t *id) -{ - HANDLE hThread; - struct threadDetails* pDetails = new threadDetails; // must be on heap - unsigned int thrdaddr; - - pDetails->func = fn; - pDetails->arg = arg; - -#if defined(HAVE__BEGINTHREADEX) - hThread = (HANDLE) _beginthreadex(NULL, 0, threadIntermediary, pDetails, 0, - &thrdaddr); - if (hThread == 0) -#elif defined(HAVE_CREATETHREAD) - hThread = CreateThread(NULL, 0, - (LPTHREAD_START_ROUTINE) threadIntermediary, - (void*) pDetails, 0, (DWORD*) &thrdaddr); - if (hThread == NULL) -#endif - { - ALOG(LOG_WARN, "thread", "WARNING: thread create failed\n"); - return false; - } - -#if defined(HAVE_CREATETHREAD) - /* close the management handle */ - CloseHandle(hThread); -#endif - - if (id != NULL) { - *id = (android_thread_id_t)thrdaddr; - } - - return true; -} - -int androidCreateRawThreadEtc(android_thread_func_t fn, - void *userData, - const char* threadName, - int32_t threadPriority, - size_t threadStackSize, - android_thread_id_t *threadId) -{ - return doCreateThread( fn, userData, threadId); -} - -android_thread_id_t androidGetThreadId() -{ - return (android_thread_id_t)GetCurrentThreadId(); -} - -// ---------------------------------------------------------------------------- -#else -#error "Threads not supported" -#endif - -// ---------------------------------------------------------------------------- - -int androidCreateThread(android_thread_func_t fn, void* arg) -{ - return createThreadEtc(fn, arg); -} - -int androidCreateThreadGetID(android_thread_func_t fn, void *arg, android_thread_id_t *id) -{ - return createThreadEtc(fn, arg, "android:unnamed_thread", - PRIORITY_DEFAULT, 0, id); -} - -static android_create_thread_fn gCreateThreadFn = androidCreateRawThreadEtc; - -int androidCreateThreadEtc(android_thread_func_t entryFunction, - void *userData, - const char* threadName, - int32_t threadPriority, - size_t threadStackSize, - android_thread_id_t *threadId) -{ - return gCreateThreadFn(entryFunction, userData, threadName, - threadPriority, threadStackSize, threadId); -} - -void androidSetCreateThreadFunc(android_create_thread_fn func) -{ - gCreateThreadFn = func; -} - -pid_t androidGetTid() -{ -#ifdef HAVE_GETTID - return gettid(); -#else - return getpid(); -#endif -} - -int androidSetThreadSchedulingGroup(pid_t tid, int grp) -{ - if (grp > ANDROID_TGROUP_MAX || grp < 0) { - return BAD_VALUE; - } - -#if defined(HAVE_PTHREADS) - pthread_once(&gDoSchedulingGroupOnce, checkDoSchedulingGroup); - if (gDoSchedulingGroup) { - // set_sched_policy does not support tid == 0 - if (tid == 0) { - tid = androidGetTid(); - } - if (set_sched_policy(tid, (grp == ANDROID_TGROUP_BG_NONINTERACT) ? - SP_BACKGROUND : SP_FOREGROUND)) { - return PERMISSION_DENIED; - } - } -#endif - - return NO_ERROR; -} - -int androidSetThreadPriority(pid_t tid, int pri) -{ - int rc = 0; - -#if defined(HAVE_PTHREADS) - int lasterr = 0; - - pthread_once(&gDoSchedulingGroupOnce, checkDoSchedulingGroup); - if (gDoSchedulingGroup) { - // set_sched_policy does not support tid == 0 - int policy_tid; - if (tid == 0) { - policy_tid = androidGetTid(); - } else { - policy_tid = tid; - } - if (pri >= ANDROID_PRIORITY_BACKGROUND) { - rc = set_sched_policy(policy_tid, SP_BACKGROUND); - } else if (getpriority(PRIO_PROCESS, tid) >= ANDROID_PRIORITY_BACKGROUND) { - rc = set_sched_policy(policy_tid, SP_FOREGROUND); - } - } - - if (rc) { - lasterr = errno; - } - - if (setpriority(PRIO_PROCESS, tid, pri) < 0) { - rc = INVALID_OPERATION; - } else { - errno = lasterr; - } -#endif - - return rc; -} - -int androidGetThreadPriority(pid_t tid) { -#if defined(HAVE_PTHREADS) - return getpriority(PRIO_PROCESS, tid); -#else - return ANDROID_PRIORITY_NORMAL; -#endif -} - -int androidGetThreadSchedulingGroup(pid_t tid) -{ - int ret = ANDROID_TGROUP_DEFAULT; - -#if defined(HAVE_PTHREADS) - // convention is to not call get/set_sched_policy methods if disabled by property - pthread_once(&gDoSchedulingGroupOnce, checkDoSchedulingGroup); - if (gDoSchedulingGroup) { - SchedPolicy policy; - // get_sched_policy does not support tid == 0 - if (tid == 0) { - tid = androidGetTid(); - } - if (get_sched_policy(tid, &policy) < 0) { - ret = INVALID_OPERATION; - } else { - switch (policy) { - case SP_BACKGROUND: - ret = ANDROID_TGROUP_BG_NONINTERACT; - break; - case SP_FOREGROUND: - ret = ANDROID_TGROUP_FG_BOOST; - break; - default: - // should not happen, as enum SchedPolicy does not have any other values - ret = INVALID_OPERATION; - break; - } - } - } -#endif - - return ret; -} - -namespace android { - -/* - * =========================================================================== - * Mutex class - * =========================================================================== - */ - -#if defined(HAVE_PTHREADS) -// implemented as inlines in threads.h -#elif defined(HAVE_WIN32_THREADS) - -Mutex::Mutex() -{ - HANDLE hMutex; - - assert(sizeof(hMutex) == sizeof(mState)); - - hMutex = CreateMutex(NULL, FALSE, NULL); - mState = (void*) hMutex; -} - -Mutex::Mutex(const char* name) -{ - // XXX: name not used for now - HANDLE hMutex; - - assert(sizeof(hMutex) == sizeof(mState)); - - hMutex = CreateMutex(NULL, FALSE, NULL); - mState = (void*) hMutex; -} - -Mutex::Mutex(int type, const char* name) -{ - // XXX: type and name not used for now - HANDLE hMutex; - - assert(sizeof(hMutex) == sizeof(mState)); - - hMutex = CreateMutex(NULL, FALSE, NULL); - mState = (void*) hMutex; -} - -Mutex::~Mutex() -{ - CloseHandle((HANDLE) mState); -} - -status_t Mutex::lock() -{ - DWORD dwWaitResult; - dwWaitResult = WaitForSingleObject((HANDLE) mState, INFINITE); - return dwWaitResult != WAIT_OBJECT_0 ? -1 : NO_ERROR; -} - -void Mutex::unlock() -{ - if (!ReleaseMutex((HANDLE) mState)) - ALOG(LOG_WARN, "thread", "WARNING: bad result from unlocking mutex\n"); -} - -status_t Mutex::tryLock() -{ - DWORD dwWaitResult; - - dwWaitResult = WaitForSingleObject((HANDLE) mState, 0); - if (dwWaitResult != WAIT_OBJECT_0 && dwWaitResult != WAIT_TIMEOUT) - ALOG(LOG_WARN, "thread", "WARNING: bad result from try-locking mutex\n"); - return (dwWaitResult == WAIT_OBJECT_0) ? 0 : -1; -} - -#else -#error "Somebody forgot to implement threads for this platform." -#endif - - -/* - * =========================================================================== - * Condition class - * =========================================================================== - */ - -#if defined(HAVE_PTHREADS) -// implemented as inlines in threads.h -#elif defined(HAVE_WIN32_THREADS) - -/* - * Windows doesn't have a condition variable solution. It's possible - * to create one, but it's easy to get it wrong. For a discussion, and - * the origin of this implementation, see: - * - * http://www.cs.wustl.edu/~schmidt/win32-cv-1.html - * - * The implementation shown on the page does NOT follow POSIX semantics. - * As an optimization they require acquiring the external mutex before - * calling signal() and broadcast(), whereas POSIX only requires grabbing - * it before calling wait(). The implementation here has been un-optimized - * to have the correct behavior. - */ -typedef struct WinCondition { - // Number of waiting threads. - int waitersCount; - - // Serialize access to waitersCount. - CRITICAL_SECTION waitersCountLock; - - // Semaphore used to queue up threads waiting for the condition to - // become signaled. - HANDLE sema; - - // An auto-reset event used by the broadcast/signal thread to wait - // for all the waiting thread(s) to wake up and be released from - // the semaphore. - HANDLE waitersDone; - - // This mutex wouldn't be necessary if we required that the caller - // lock the external mutex before calling signal() and broadcast(). - // I'm trying to mimic pthread semantics though. - HANDLE internalMutex; - - // Keeps track of whether we were broadcasting or signaling. This - // allows us to optimize the code if we're just signaling. - bool wasBroadcast; - - status_t wait(WinCondition* condState, HANDLE hMutex, nsecs_t* abstime) - { - // Increment the wait count, avoiding race conditions. - EnterCriticalSection(&condState->waitersCountLock); - condState->waitersCount++; - //printf("+++ wait: incr waitersCount to %d (tid=%ld)\n", - // condState->waitersCount, getThreadId()); - LeaveCriticalSection(&condState->waitersCountLock); - - DWORD timeout = INFINITE; - if (abstime) { - nsecs_t reltime = *abstime - systemTime(); - if (reltime < 0) - reltime = 0; - timeout = reltime/1000000; - } - - // Atomically release the external mutex and wait on the semaphore. - DWORD res = - SignalObjectAndWait(hMutex, condState->sema, timeout, FALSE); - - //printf("+++ wait: awake (tid=%ld)\n", getThreadId()); - - // Reacquire lock to avoid race conditions. - EnterCriticalSection(&condState->waitersCountLock); - - // No longer waiting. - condState->waitersCount--; - - // Check to see if we're the last waiter after a broadcast. - bool lastWaiter = (condState->wasBroadcast && condState->waitersCount == 0); - - //printf("+++ wait: lastWaiter=%d (wasBc=%d wc=%d)\n", - // lastWaiter, condState->wasBroadcast, condState->waitersCount); - - LeaveCriticalSection(&condState->waitersCountLock); - - // If we're the last waiter thread during this particular broadcast - // then signal broadcast() that we're all awake. It'll drop the - // internal mutex. - if (lastWaiter) { - // Atomically signal the "waitersDone" event and wait until we - // can acquire the internal mutex. We want to do this in one step - // because it ensures that everybody is in the mutex FIFO before - // any thread has a chance to run. Without it, another thread - // could wake up, do work, and hop back in ahead of us. - SignalObjectAndWait(condState->waitersDone, condState->internalMutex, - INFINITE, FALSE); - } else { - // Grab the internal mutex. - WaitForSingleObject(condState->internalMutex, INFINITE); - } - - // Release the internal and grab the external. - ReleaseMutex(condState->internalMutex); - WaitForSingleObject(hMutex, INFINITE); - - return res == WAIT_OBJECT_0 ? NO_ERROR : -1; - } -} WinCondition; - -/* - * Constructor. Set up the WinCondition stuff. - */ -Condition::Condition() -{ - WinCondition* condState = new WinCondition; - - condState->waitersCount = 0; - condState->wasBroadcast = false; - // semaphore: no security, initial value of 0 - condState->sema = CreateSemaphore(NULL, 0, 0x7fffffff, NULL); - InitializeCriticalSection(&condState->waitersCountLock); - // auto-reset event, not signaled initially - condState->waitersDone = CreateEvent(NULL, FALSE, FALSE, NULL); - // used so we don't have to lock external mutex on signal/broadcast - condState->internalMutex = CreateMutex(NULL, FALSE, NULL); - - mState = condState; -} - -/* - * Destructor. Free Windows resources as well as our allocated storage. - */ -Condition::~Condition() -{ - WinCondition* condState = (WinCondition*) mState; - if (condState != NULL) { - CloseHandle(condState->sema); - CloseHandle(condState->waitersDone); - delete condState; - } -} - - -status_t Condition::wait(Mutex& mutex) -{ - WinCondition* condState = (WinCondition*) mState; - HANDLE hMutex = (HANDLE) mutex.mState; - - return ((WinCondition*)mState)->wait(condState, hMutex, NULL); -} - -status_t Condition::waitRelative(Mutex& mutex, nsecs_t reltime) -{ - WinCondition* condState = (WinCondition*) mState; - HANDLE hMutex = (HANDLE) mutex.mState; - nsecs_t absTime = systemTime()+reltime; - - return ((WinCondition*)mState)->wait(condState, hMutex, &absTime); -} - -/* - * Signal the condition variable, allowing one thread to continue. - */ -void Condition::signal() -{ - WinCondition* condState = (WinCondition*) mState; - - // Lock the internal mutex. This ensures that we don't clash with - // broadcast(). - WaitForSingleObject(condState->internalMutex, INFINITE); - - EnterCriticalSection(&condState->waitersCountLock); - bool haveWaiters = (condState->waitersCount > 0); - LeaveCriticalSection(&condState->waitersCountLock); - - // If no waiters, then this is a no-op. Otherwise, knock the semaphore - // down a notch. - if (haveWaiters) - ReleaseSemaphore(condState->sema, 1, 0); - - // Release internal mutex. - ReleaseMutex(condState->internalMutex); -} - -/* - * Signal the condition variable, allowing all threads to continue. - * - * First we have to wake up all threads waiting on the semaphore, then - * we wait until all of the threads have actually been woken before - * releasing the internal mutex. This ensures that all threads are woken. - */ -void Condition::broadcast() -{ - WinCondition* condState = (WinCondition*) mState; - - // Lock the internal mutex. This keeps the guys we're waking up - // from getting too far. - WaitForSingleObject(condState->internalMutex, INFINITE); - - EnterCriticalSection(&condState->waitersCountLock); - bool haveWaiters = false; - - if (condState->waitersCount > 0) { - haveWaiters = true; - condState->wasBroadcast = true; - } - - if (haveWaiters) { - // Wake up all the waiters. - ReleaseSemaphore(condState->sema, condState->waitersCount, 0); - - LeaveCriticalSection(&condState->waitersCountLock); - - // Wait for all awakened threads to acquire the counting semaphore. - // The last guy who was waiting sets this. - WaitForSingleObject(condState->waitersDone, INFINITE); - - // Reset wasBroadcast. (No crit section needed because nobody - // else can wake up to poke at it.) - condState->wasBroadcast = 0; - } else { - // nothing to do - LeaveCriticalSection(&condState->waitersCountLock); - } - - // Release internal mutex. - ReleaseMutex(condState->internalMutex); -} - -#else -#error "condition variables not supported on this platform" -#endif - -// ---------------------------------------------------------------------------- - -/* - * This is our thread object! - */ - -Thread::Thread(bool canCallJava) - : mCanCallJava(canCallJava), - mThread(thread_id_t(-1)), - mLock("Thread::mLock"), - mStatus(NO_ERROR), - mExitPending(false), mRunning(false) -#ifdef HAVE_ANDROID_OS - , mTid(-1) -#endif -{ -} - -Thread::~Thread() -{ -} - -status_t Thread::readyToRun() -{ - return NO_ERROR; -} - -status_t Thread::run(const char* name, int32_t priority, size_t stack) -{ - Mutex::Autolock _l(mLock); - - if (mRunning) { - // thread already started - return INVALID_OPERATION; - } - - // reset status and exitPending to their default value, so we can - // try again after an error happened (either below, or in readyToRun()) - mStatus = NO_ERROR; - mExitPending = false; - mThread = thread_id_t(-1); - - // hold a strong reference on ourself - mHoldSelf = this; - - mRunning = true; - - bool res; - if (mCanCallJava) { - res = createThreadEtc(_threadLoop, - this, name, priority, stack, &mThread); - } else { - res = androidCreateRawThreadEtc(_threadLoop, - this, name, priority, stack, &mThread); - } - - if (res == false) { - mStatus = UNKNOWN_ERROR; // something happened! - mRunning = false; - mThread = thread_id_t(-1); - mHoldSelf.clear(); // "this" may have gone away after this. - - return UNKNOWN_ERROR; - } - - // Do not refer to mStatus here: The thread is already running (may, in fact - // already have exited with a valid mStatus result). The NO_ERROR indication - // here merely indicates successfully starting the thread and does not - // imply successful termination/execution. - return NO_ERROR; - - // Exiting scope of mLock is a memory barrier and allows new thread to run -} - -int Thread::_threadLoop(void* user) -{ - Thread* const self = static_cast<Thread*>(user); - - sp<Thread> strong(self->mHoldSelf); - wp<Thread> weak(strong); - self->mHoldSelf.clear(); - -#ifdef HAVE_ANDROID_OS - // this is very useful for debugging with gdb - self->mTid = gettid(); -#endif - - bool first = true; - - do { - bool result; - if (first) { - first = false; - self->mStatus = self->readyToRun(); - result = (self->mStatus == NO_ERROR); - - if (result && !self->exitPending()) { - // Binder threads (and maybe others) rely on threadLoop - // running at least once after a successful ::readyToRun() - // (unless, of course, the thread has already been asked to exit - // at that point). - // This is because threads are essentially used like this: - // (new ThreadSubclass())->run(); - // The caller therefore does not retain a strong reference to - // the thread and the thread would simply disappear after the - // successful ::readyToRun() call instead of entering the - // threadLoop at least once. - result = self->threadLoop(); - } - } else { - result = self->threadLoop(); - } - - // establish a scope for mLock - { - Mutex::Autolock _l(self->mLock); - if (result == false || self->mExitPending) { - self->mExitPending = true; - self->mRunning = false; - // clear thread ID so that requestExitAndWait() does not exit if - // called by a new thread using the same thread ID as this one. - self->mThread = thread_id_t(-1); - // note that interested observers blocked in requestExitAndWait are - // awoken by broadcast, but blocked on mLock until break exits scope - self->mThreadExitedCondition.broadcast(); - break; - } - } - - // Release our strong reference, to let a chance to the thread - // to die a peaceful death. - strong.clear(); - // And immediately, re-acquire a strong reference for the next loop - strong = weak.promote(); - } while(strong != 0); - - return 0; -} - -void Thread::requestExit() -{ - Mutex::Autolock _l(mLock); - mExitPending = true; -} - -status_t Thread::requestExitAndWait() -{ - Mutex::Autolock _l(mLock); - if (mThread == getThreadId()) { - ALOGW( - "Thread (this=%p): don't call waitForExit() from this " - "Thread object's thread. It's a guaranteed deadlock!", - this); - - return WOULD_BLOCK; - } - - mExitPending = true; - - while (mRunning == true) { - mThreadExitedCondition.wait(mLock); - } - // This next line is probably not needed any more, but is being left for - // historical reference. Note that each interested party will clear flag. - mExitPending = false; - - return mStatus; -} - -status_t Thread::join() -{ - Mutex::Autolock _l(mLock); - if (mThread == getThreadId()) { - ALOGW( - "Thread (this=%p): don't call join() from this " - "Thread object's thread. It's a guaranteed deadlock!", - this); - - return WOULD_BLOCK; - } - - while (mRunning == true) { - mThreadExitedCondition.wait(mLock); - } - - return mStatus; -} - -#ifdef HAVE_ANDROID_OS -pid_t Thread::getTid() const -{ - // mTid is not defined until the child initializes it, and the caller may need it earlier - Mutex::Autolock _l(mLock); - pid_t tid; - if (mRunning) { - pthread_t pthread = android_thread_id_t_to_pthread(mThread); - tid = __pthread_gettid(pthread); - } else { - ALOGW("Thread (this=%p): getTid() is undefined before run()", this); - tid = -1; - } - return tid; -} -#endif - -bool Thread::exitPending() const -{ - Mutex::Autolock _l(mLock); - return mExitPending; -} - - - -}; // namespace android |