| /* |
| * 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. |
| */ |
| |
| #ifndef _LIBS_UTILS_THREADS_H |
| #define _LIBS_UTILS_THREADS_H |
| |
| #include <stdint.h> |
| #include <sys/types.h> |
| #include <time.h> |
| |
| #if defined(HAVE_PTHREADS) |
| # include <pthread.h> |
| #endif |
| |
| // ------------------------------------------------------------------ |
| // C API |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| typedef void* android_thread_id_t; |
| |
| typedef int (*android_thread_func_t)(void*); |
| |
| enum { |
| /* |
| * *********************************************** |
| * ** Keep in sync with android.os.Process.java ** |
| * *********************************************** |
| * |
| * This maps directly to the "nice" priorites we use in Android. |
| * A thread priority should be chosen inverse-proportinally to |
| * the amount of work the thread is expected to do. The more work |
| * a thread will do, the less favorable priority it should get so that |
| * it doesn't starve the system. Threads not behaving properly might |
| * be "punished" by the kernel. |
| * Use the levels below when appropriate. Intermediate values are |
| * acceptable, preferably use the {MORE|LESS}_FAVORABLE constants below. |
| */ |
| ANDROID_PRIORITY_LOWEST = 19, |
| |
| /* use for background tasks */ |
| ANDROID_PRIORITY_BACKGROUND = 10, |
| |
| /* most threads run at normal priority */ |
| ANDROID_PRIORITY_NORMAL = 0, |
| |
| /* threads currently running a UI that the user is interacting with */ |
| ANDROID_PRIORITY_FOREGROUND = -2, |
| |
| /* the main UI thread has a slightly more favorable priority */ |
| ANDROID_PRIORITY_DISPLAY = -4, |
| |
| /* ui service treads might want to run at a urgent display (uncommon) */ |
| ANDROID_PRIORITY_URGENT_DISPLAY = -8, |
| |
| /* all normal audio threads */ |
| ANDROID_PRIORITY_AUDIO = -16, |
| |
| /* service audio threads (uncommon) */ |
| ANDROID_PRIORITY_URGENT_AUDIO = -19, |
| |
| /* should never be used in practice. regular process might not |
| * be allowed to use this level */ |
| ANDROID_PRIORITY_HIGHEST = -20, |
| |
| ANDROID_PRIORITY_DEFAULT = ANDROID_PRIORITY_NORMAL, |
| ANDROID_PRIORITY_MORE_FAVORABLE = -1, |
| ANDROID_PRIORITY_LESS_FAVORABLE = +1, |
| }; |
| |
| enum { |
| ANDROID_TGROUP_DEFAULT = 0, |
| ANDROID_TGROUP_BG_NONINTERACT = 1, |
| ANDROID_TGROUP_FG_BOOST = 2, |
| ANDROID_TGROUP_MAX = ANDROID_TGROUP_FG_BOOST, |
| }; |
| |
| // Create and run a new thread. |
| extern int androidCreateThread(android_thread_func_t, void *); |
| |
| // Create thread with lots of parameters |
| extern int androidCreateThreadEtc(android_thread_func_t entryFunction, |
| void *userData, |
| const char* threadName, |
| int32_t threadPriority, |
| size_t threadStackSize, |
| android_thread_id_t *threadId); |
| |
| // Get some sort of unique identifier for the current thread. |
| extern android_thread_id_t androidGetThreadId(); |
| |
| // Low-level thread creation -- never creates threads that can |
| // interact with the Java VM. |
| extern int androidCreateRawThreadEtc(android_thread_func_t entryFunction, |
| void *userData, |
| const char* threadName, |
| int32_t threadPriority, |
| size_t threadStackSize, |
| android_thread_id_t *threadId); |
| |
| // Used by the Java Runtime to control how threads are created, so that |
| // they can be proper and lovely Java threads. |
| typedef int (*android_create_thread_fn)(android_thread_func_t entryFunction, |
| void *userData, |
| const char* threadName, |
| int32_t threadPriority, |
| size_t threadStackSize, |
| android_thread_id_t *threadId); |
| |
| extern void androidSetCreateThreadFunc(android_create_thread_fn func); |
| |
| // ------------------------------------------------------------------ |
| // Extra functions working with raw pids. |
| |
| // Get pid for the current thread. |
| extern pid_t androidGetTid(); |
| |
| // Change the scheduling group of a particular thread. The group |
| // should be one of the ANDROID_TGROUP constants. Returns BAD_VALUE if |
| // grp is out of range, else another non-zero value with errno set if |
| // the operation failed. |
| extern int androidSetThreadSchedulingGroup(pid_t tid, int grp); |
| |
| // Change the priority AND scheduling group of a particular thread. The priority |
| // should be one of the ANDROID_PRIORITY constants. Returns INVALID_OPERATION |
| // if the priority set failed, else another value if just the group set failed; |
| // in either case errno is set. |
| extern int androidSetThreadPriority(pid_t tid, int prio); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| // ------------------------------------------------------------------ |
| // C++ API |
| |
| #ifdef __cplusplus |
| |
| #include <utils/Errors.h> |
| #include <utils/RefBase.h> |
| #include <utils/Timers.h> |
| |
| namespace android { |
| |
| typedef android_thread_id_t thread_id_t; |
| |
| typedef android_thread_func_t thread_func_t; |
| |
| enum { |
| PRIORITY_LOWEST = ANDROID_PRIORITY_LOWEST, |
| PRIORITY_BACKGROUND = ANDROID_PRIORITY_BACKGROUND, |
| PRIORITY_NORMAL = ANDROID_PRIORITY_NORMAL, |
| PRIORITY_FOREGROUND = ANDROID_PRIORITY_FOREGROUND, |
| PRIORITY_DISPLAY = ANDROID_PRIORITY_DISPLAY, |
| PRIORITY_URGENT_DISPLAY = ANDROID_PRIORITY_URGENT_DISPLAY, |
| PRIORITY_AUDIO = ANDROID_PRIORITY_AUDIO, |
| PRIORITY_URGENT_AUDIO = ANDROID_PRIORITY_URGENT_AUDIO, |
| PRIORITY_HIGHEST = ANDROID_PRIORITY_HIGHEST, |
| PRIORITY_DEFAULT = ANDROID_PRIORITY_DEFAULT, |
| PRIORITY_MORE_FAVORABLE = ANDROID_PRIORITY_MORE_FAVORABLE, |
| PRIORITY_LESS_FAVORABLE = ANDROID_PRIORITY_LESS_FAVORABLE, |
| }; |
| |
| // Create and run a new thread. |
| inline bool createThread(thread_func_t f, void *a) { |
| return androidCreateThread(f, a) ? true : false; |
| } |
| |
| // Create thread with lots of parameters |
| inline bool createThreadEtc(thread_func_t entryFunction, |
| void *userData, |
| const char* threadName = "android:unnamed_thread", |
| int32_t threadPriority = PRIORITY_DEFAULT, |
| size_t threadStackSize = 0, |
| thread_id_t *threadId = 0) |
| { |
| return androidCreateThreadEtc(entryFunction, userData, threadName, |
| threadPriority, threadStackSize, threadId) ? true : false; |
| } |
| |
| // Get some sort of unique identifier for the current thread. |
| inline thread_id_t getThreadId() { |
| return androidGetThreadId(); |
| } |
| |
| /*****************************************************************************/ |
| |
| /* |
| * Simple mutex class. The implementation is system-dependent. |
| * |
| * The mutex must be unlocked by the thread that locked it. They are not |
| * recursive, i.e. the same thread can't lock it multiple times. |
| */ |
| class Mutex { |
| public: |
| enum { |
| NORMAL = 0, |
| SHARED = 1 |
| }; |
| |
| Mutex(); |
| Mutex(const char* name); |
| Mutex(int type, const char* name = NULL); |
| ~Mutex(); |
| |
| // lock or unlock the mutex |
| status_t lock(); |
| void unlock(); |
| |
| // lock if possible; returns 0 on success, error otherwise |
| status_t tryLock(); |
| |
| // Manages the mutex automatically. It'll be locked when Autolock is |
| // constructed and released when Autolock goes out of scope. |
| class Autolock { |
| public: |
| inline Autolock(Mutex& mutex) : mLock(mutex) { mLock.lock(); } |
| inline Autolock(Mutex* mutex) : mLock(*mutex) { mLock.lock(); } |
| inline ~Autolock() { mLock.unlock(); } |
| private: |
| Mutex& mLock; |
| }; |
| |
| private: |
| friend class Condition; |
| |
| // A mutex cannot be copied |
| Mutex(const Mutex&); |
| Mutex& operator = (const Mutex&); |
| |
| #if defined(HAVE_PTHREADS) |
| pthread_mutex_t mMutex; |
| #else |
| void _init(); |
| void* mState; |
| #endif |
| }; |
| |
| #if defined(HAVE_PTHREADS) |
| |
| inline Mutex::Mutex() { |
| pthread_mutex_init(&mMutex, NULL); |
| } |
| inline Mutex::Mutex(const char* name) { |
| pthread_mutex_init(&mMutex, NULL); |
| } |
| inline Mutex::Mutex(int type, const char* name) { |
| if (type == SHARED) { |
| pthread_mutexattr_t attr; |
| pthread_mutexattr_init(&attr); |
| pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED); |
| pthread_mutex_init(&mMutex, &attr); |
| pthread_mutexattr_destroy(&attr); |
| } else { |
| pthread_mutex_init(&mMutex, NULL); |
| } |
| } |
| inline Mutex::~Mutex() { |
| pthread_mutex_destroy(&mMutex); |
| } |
| inline status_t Mutex::lock() { |
| return -pthread_mutex_lock(&mMutex); |
| } |
| inline void Mutex::unlock() { |
| pthread_mutex_unlock(&mMutex); |
| } |
| inline status_t Mutex::tryLock() { |
| return -pthread_mutex_trylock(&mMutex); |
| } |
| |
| #endif // HAVE_PTHREADS |
| |
| /* |
| * Automatic mutex. Declare one of these at the top of a function. |
| * When the function returns, it will go out of scope, and release the |
| * mutex. |
| */ |
| |
| typedef Mutex::Autolock AutoMutex; |
| |
| /*****************************************************************************/ |
| |
| /* |
| * Condition variable class. The implementation is system-dependent. |
| * |
| * Condition variables are paired up with mutexes. Lock the mutex, |
| * call wait(), then either re-wait() if things aren't quite what you want, |
| * or unlock the mutex and continue. All threads calling wait() must |
| * use the same mutex for a given Condition. |
| */ |
| class Condition { |
| public: |
| Condition(); |
| ~Condition(); |
| // Wait on the condition variable. Lock the mutex before calling. |
| status_t wait(Mutex& mutex); |
| // same with relative timeout |
| status_t waitRelative(Mutex& mutex, nsecs_t reltime); |
| // Signal the condition variable, allowing one thread to continue. |
| void signal(); |
| // Signal the condition variable, allowing all threads to continue. |
| void broadcast(); |
| |
| private: |
| #if defined(HAVE_PTHREADS) |
| pthread_cond_t mCond; |
| #else |
| void* mState; |
| #endif |
| }; |
| |
| #if defined(HAVE_PTHREADS) |
| |
| inline Condition::Condition() { |
| pthread_cond_init(&mCond, NULL); |
| } |
| inline Condition::~Condition() { |
| pthread_cond_destroy(&mCond); |
| } |
| inline status_t Condition::wait(Mutex& mutex) { |
| return -pthread_cond_wait(&mCond, &mutex.mMutex); |
| } |
| inline status_t Condition::waitRelative(Mutex& mutex, nsecs_t reltime) { |
| #if defined(HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE) |
| struct timespec ts; |
| ts.tv_sec = reltime/1000000000; |
| ts.tv_nsec = reltime%1000000000; |
| return -pthread_cond_timedwait_relative_np(&mCond, &mutex.mMutex, &ts); |
| #else // HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE |
| struct timespec ts; |
| #if defined(HAVE_POSIX_CLOCKS) |
| clock_gettime(CLOCK_REALTIME, &ts); |
| #else // HAVE_POSIX_CLOCKS |
| // we don't support the clocks here. |
| struct timeval t; |
| gettimeofday(&t, NULL); |
| ts.tv_sec = t.tv_sec; |
| ts.tv_nsec= t.tv_usec*1000; |
| #endif // HAVE_POSIX_CLOCKS |
| ts.tv_sec += reltime/1000000000; |
| ts.tv_nsec+= reltime%1000000000; |
| if (ts.tv_nsec >= 1000000000) { |
| ts.tv_nsec -= 1000000000; |
| ts.tv_sec += 1; |
| } |
| return -pthread_cond_timedwait(&mCond, &mutex.mMutex, &ts); |
| #endif // HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE |
| } |
| inline void Condition::signal() { |
| pthread_cond_signal(&mCond); |
| } |
| inline void Condition::broadcast() { |
| pthread_cond_broadcast(&mCond); |
| } |
| |
| #endif // HAVE_PTHREADS |
| |
| /*****************************************************************************/ |
| |
| /* |
| * This is our spiffy thread object! |
| */ |
| |
| class Thread : virtual public RefBase |
| { |
| public: |
| // Create a Thread object, but doesn't create or start the associated |
| // thread. See the run() method. |
| Thread(bool canCallJava = true); |
| virtual ~Thread(); |
| |
| // Start the thread in threadLoop() which needs to be implemented. |
| virtual status_t run( const char* name = 0, |
| int32_t priority = PRIORITY_DEFAULT, |
| size_t stack = 0); |
| |
| // Ask this object's thread to exit. This function is asynchronous, when the |
| // function returns the thread might still be running. Of course, this |
| // function can be called from a different thread. |
| virtual void requestExit(); |
| |
| // Good place to do one-time initializations |
| virtual status_t readyToRun(); |
| |
| // Call requestExit() and wait until this object's thread exits. |
| // BE VERY CAREFUL of deadlocks. In particular, it would be silly to call |
| // this function from this object's thread. Will return WOULD_BLOCK in |
| // that case. |
| status_t requestExitAndWait(); |
| |
| protected: |
| // exitPending() returns true if requestExit() has been called. |
| bool exitPending() const; |
| |
| private: |
| // Derived class must implement threadLoop(). The thread starts its life |
| // here. There are two ways of using the Thread object: |
| // 1) loop: if threadLoop() returns true, it will be called again if |
| // requestExit() wasn't called. |
| // 2) once: if threadLoop() returns false, the thread will exit upon return. |
| virtual bool threadLoop() = 0; |
| |
| private: |
| Thread& operator=(const Thread&); |
| static int _threadLoop(void* user); |
| const bool mCanCallJava; |
| thread_id_t mThread; |
| Mutex mLock; |
| Condition mThreadExitedCondition; |
| status_t mStatus; |
| volatile bool mExitPending; |
| volatile bool mRunning; |
| sp<Thread> mHoldSelf; |
| #if HAVE_ANDROID_OS |
| int mTid; |
| #endif |
| }; |
| |
| |
| }; // namespace android |
| |
| #endif // __cplusplus |
| |
| #endif // _LIBS_UTILS_THREADS_H |