diff options
Diffstat (limited to 'src/libstrongswan/threading')
| -rw-r--r-- | src/libstrongswan/threading/mutex.c | 40 | ||||
| -rw-r--r-- | src/libstrongswan/threading/rwlock.c | 233 | ||||
| -rw-r--r-- | src/libstrongswan/threading/rwlock_condvar.h | 90 | ||||
| -rw-r--r-- | src/libstrongswan/threading/semaphore.c | 179 | ||||
| -rw-r--r-- | src/libstrongswan/threading/semaphore.h | 85 | ||||
| -rw-r--r-- | src/libstrongswan/threading/spinlock.c | 136 | ||||
| -rw-r--r-- | src/libstrongswan/threading/spinlock.h | 58 | ||||
| -rw-r--r-- | src/libstrongswan/threading/thread.c | 4 | ||||
| -rw-r--r-- | src/libstrongswan/threading/thread_value.c | 21 |
9 files changed, 792 insertions, 54 deletions
diff --git a/src/libstrongswan/threading/mutex.c b/src/libstrongswan/threading/mutex.c index 3bdb3bf29..2ef918a28 100644 --- a/src/libstrongswan/threading/mutex.c +++ b/src/libstrongswan/threading/mutex.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2008-2009 Tobias Brunner + * Copyright (C) 2008-2012 Tobias Brunner * Copyright (C) 2008 Martin Willi * Hochschule fuer Technik Rapperswil * @@ -73,9 +73,9 @@ struct private_r_mutex_t { pthread_t thread; /** - * times we have locked the lock, stored per thread + * times the current thread locked the mutex */ - pthread_key_t times; + u_int times; }; /** @@ -127,35 +127,24 @@ METHOD(mutex_t, lock_r, void, { pthread_t self = pthread_self(); - if (this->thread == self) + if (pthread_equal(this->thread, self)) { - uintptr_t times; - - /* times++ */ - times = (uintptr_t)pthread_getspecific(this->times); - pthread_setspecific(this->times, (void*)times + 1); + this->times++; } else { lock(&this->generic); this->thread = self; - /* times = 1 */ - pthread_setspecific(this->times, (void*)1); + this->times = 1; } } METHOD(mutex_t, unlock_r, void, private_r_mutex_t *this) { - uintptr_t times; - - /* times-- */ - times = (uintptr_t)pthread_getspecific(this->times); - pthread_setspecific(this->times, (void*)--times); - - if (times == 0) + if (--this->times == 0) { - this->thread = 0; + memset(&this->thread, 0, sizeof(this->thread)); unlock(&this->generic); } } @@ -173,7 +162,6 @@ METHOD(mutex_t, mutex_destroy_r, void, { profiler_cleanup(&this->generic.profile); pthread_mutex_destroy(&this->generic.mutex); - pthread_key_delete(this->times); free(this); } @@ -200,7 +188,6 @@ mutex_t *mutex_create(mutex_type_t type) ); pthread_mutex_init(&this->generic.mutex, NULL); - pthread_key_create(&this->times, NULL); profiler_init(&this->generic.profile); return &this->generic.public; @@ -233,11 +220,15 @@ METHOD(condvar_t, wait_, void, if (mutex->recursive) { private_r_mutex_t* recursive = (private_r_mutex_t*)mutex; + u_int times; + /* keep track of the number of times this thread locked the mutex */ + times = recursive->times; /* mutex owner gets cleared during condvar wait */ - recursive->thread = 0; + memset(&recursive->thread, 0, sizeof(recursive->thread)); pthread_cond_wait(&this->condvar, &mutex->mutex); recursive->thread = pthread_self(); + recursive->times = times; } else { @@ -262,11 +253,14 @@ METHOD(condvar_t, timed_wait_abs, bool, if (mutex->recursive) { private_r_mutex_t* recursive = (private_r_mutex_t*)mutex; + u_int times; - recursive->thread = 0; + times = recursive->times; + memset(&recursive->thread, 0, sizeof(recursive->thread)); timed_out = pthread_cond_timedwait(&this->condvar, &mutex->mutex, &ts) == ETIMEDOUT; recursive->thread = pthread_self(); + recursive->times = times; } else { diff --git a/src/libstrongswan/threading/rwlock.c b/src/libstrongswan/threading/rwlock.c index 15dc0b334..7097a8e8c 100644 --- a/src/libstrongswan/threading/rwlock.c +++ b/src/libstrongswan/threading/rwlock.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2008-2009 Tobias Brunner + * Copyright (C) 2008-2012 Tobias Brunner * Copyright (C) 2008 Martin Willi * Hochschule fuer Technik Rapperswil * @@ -21,11 +21,14 @@ #include <debug.h> #include "rwlock.h" +#include "rwlock_condvar.h" +#include "thread.h" #include "condvar.h" #include "mutex.h" #include "lock_profiler.h" typedef struct private_rwlock_t private_rwlock_t; +typedef struct private_rwlock_condvar_t private_rwlock_condvar_t; /** * private data of rwlock @@ -72,9 +75,9 @@ struct private_rwlock_t { u_int reader_count; /** - * current writer thread, if any + * TRUE, if a writer is holding the lock currently */ - pthread_t writer; + bool writer; #endif /* HAVE_PTHREAD_RWLOCK_INIT */ @@ -84,6 +87,27 @@ struct private_rwlock_t { lock_profile_t profile; }; +/** + * private data of condvar + */ +struct private_rwlock_condvar_t { + + /** + * public interface + */ + rwlock_condvar_t public; + + /** + * mutex used to implement rwlock condvar + */ + mutex_t *mutex; + + /** + * regular condvar to implement rwlock condvar + */ + condvar_t *condvar; +}; + #ifdef HAVE_PTHREAD_RWLOCK_INIT @@ -175,37 +199,81 @@ rwlock_t *rwlock_create(rwlock_type_t type) /** * This implementation of the rwlock_t interface uses mutex_t and condvar_t - * primitives, if the pthread_rwlock_* group of functions is not available. + * primitives, if the pthread_rwlock_* group of functions is not available or + * don't allow recursive locking for readers. * * The following constraints are enforced: * - Multiple readers can hold the lock at the same time. * - Only a single writer can hold the lock at any given time. * - A writer must block until all readers have released the lock before * obtaining the lock exclusively. - * - Readers that arrive while a writer is waiting to acquire the lock will - * block until after the writer has obtained and released the lock. + * - Readers that don't hold any read lock and arrive while a writer is + * waiting to acquire the lock will block until after the writer has + * obtained and released the lock. * These constraints allow for read sharing, prevent write sharing, prevent - * read-write sharing and prevent starvation of writers by a steady stream - * of incoming readers. Reader starvation is not prevented (this could happen - * if there are more writers than readers). + * read-write sharing and (largely) prevent starvation of writers by a steady + * stream of incoming readers. Reader starvation is not prevented (this could + * happen if there are more writers than readers). * - * The implementation does not support recursive locking and readers must not - * acquire the lock exclusively at the same time and vice-versa (this is not - * checked or enforced so behave yourself to prevent deadlocks). + * The implementation supports recursive locking of the read lock but not of + * the write lock. Readers must not acquire the lock exclusively at the same + * time and vice-versa (this is not checked or enforced so behave yourself to + * prevent deadlocks). + * + * Since writers are preferred a thread currently holding the read lock that + * tries to acquire the read lock recursively while a writer is waiting would + * result in a deadlock. In order to avoid having to use a thread-specific + * value for each rwlock_t (or a list of threads) to keep track if a thread + * already acquired the read lock we use a single thread-specific value for all + * rwlock_t objects that keeps track of how many read locks a thread currently + * holds. Preferring readers that already hold ANY read locks prevents this + * deadlock while it still largely avoids writer starvation (for locks that can + * only be acquired while holding another read lock this will obviously not + * work). */ +/** + * Keep track of how many read locks a thread holds. + */ +static pthread_key_t is_reader; + +/** + * Only initialize the read lock counter once. + */ +static pthread_once_t is_reader_initialized = PTHREAD_ONCE_INIT; + +/** + * Initialize the read lock counter. + */ +static void initialize_is_reader() +{ + pthread_key_create(&is_reader, NULL); +} + METHOD(rwlock_t, read_lock, void, private_rwlock_t *this) { + uintptr_t reading; + + reading = (uintptr_t)pthread_getspecific(is_reader); profiler_start(&this->profile); this->mutex->lock(this->mutex); - while (this->writer || this->waiting_writers) + if (!this->writer && reading > 0) { - this->readers->wait(this->readers, this->mutex); + /* directly allow threads that hold ANY read locks, to avoid a deadlock + * caused by preferring writers in the loop below */ + } + else + { + while (this->writer || this->waiting_writers) + { + this->readers->wait(this->readers, this->mutex); + } } this->reader_count++; profiler_end(&this->profile); this->mutex->unlock(this->mutex); + pthread_setspecific(is_reader, (void*)(reading + 1)); } METHOD(rwlock_t, write_lock, void, @@ -219,7 +287,7 @@ METHOD(rwlock_t, write_lock, void, this->writers->wait(this->writers, this->mutex); } this->waiting_writers--; - this->writer = pthread_self(); + this->writer = TRUE; profiler_end(&this->profile); this->mutex->unlock(this->mutex); } @@ -231,8 +299,7 @@ METHOD(rwlock_t, try_write_lock, bool, this->mutex->lock(this->mutex); if (!this->writer && !this->reader_count) { - res = TRUE; - this->writer = pthread_self(); + res = this->writer = TRUE; } this->mutex->unlock(this->mutex); return res; @@ -242,9 +309,20 @@ METHOD(rwlock_t, unlock, void, private_rwlock_t *this) { this->mutex->lock(this->mutex); - if (this->writer == pthread_self()) + if (this->writer) + { + this->writer = FALSE; + } + else + { + uintptr_t reading; + + this->reader_count--; + reading = (uintptr_t)pthread_getspecific(is_reader); + pthread_setspecific(is_reader, (void*)(reading - 1)); + } + if (!this->reader_count) { - this->writer = 0; if (this->waiting_writers) { this->writers->signal(this->writers); @@ -254,14 +332,6 @@ METHOD(rwlock_t, unlock, void, this->readers->broadcast(this->readers); } } - else - { - this->reader_count--; - if (!this->reader_count) - { - this->writers->signal(this->writers); - } - } this->mutex->unlock(this->mutex); } @@ -280,6 +350,8 @@ METHOD(rwlock_t, destroy, void, */ rwlock_t *rwlock_create(rwlock_type_t type) { + pthread_once(&is_reader_initialized, initialize_is_reader); + switch (type) { case RWLOCK_TYPE_DEFAULT: @@ -309,3 +381,110 @@ rwlock_t *rwlock_create(rwlock_type_t type) #endif /* HAVE_PTHREAD_RWLOCK_INIT */ + +METHOD(rwlock_condvar_t, wait_, void, + private_rwlock_condvar_t *this, rwlock_t *lock) +{ + /* at this point we have the write lock locked, to make signals more + * predictable we try to prevent other threads from signaling by acquiring + * the mutex while we still hold the write lock (this assumes they will + * hold the write lock themselves when signaling, which is not mandatory) */ + this->mutex->lock(this->mutex); + /* unlock the rwlock and wait for a signal */ + lock->unlock(lock); + /* if the calling thread enabled thread cancelability we want to replicate + * the behavior of the regular condvar, i.e. the lock will be held again + * before executing cleanup functions registered by the calling thread */ + thread_cleanup_push((thread_cleanup_t)lock->write_lock, lock); + thread_cleanup_push((thread_cleanup_t)this->mutex->unlock, this->mutex); + this->condvar->wait(this->condvar, this->mutex); + /* we release the mutex to allow other threads into the condvar (might even + * be required so we can acquire the lock again below) */ + thread_cleanup_pop(TRUE); + /* finally we reacquire the lock we held previously */ + thread_cleanup_pop(TRUE); +} + +METHOD(rwlock_condvar_t, timed_wait_abs, bool, + private_rwlock_condvar_t *this, rwlock_t *lock, timeval_t time) +{ + bool timed_out; + + /* see wait() above for details on what is going on here */ + this->mutex->lock(this->mutex); + lock->unlock(lock); + thread_cleanup_push((thread_cleanup_t)lock->write_lock, lock); + thread_cleanup_push((thread_cleanup_t)this->mutex->unlock, this->mutex); + timed_out = this->condvar->timed_wait_abs(this->condvar, this->mutex, time); + thread_cleanup_pop(TRUE); + thread_cleanup_pop(!timed_out); + return timed_out; +} + +METHOD(rwlock_condvar_t, timed_wait, bool, + private_rwlock_condvar_t *this, rwlock_t *lock, u_int timeout) +{ + timeval_t tv; + u_int s, ms; + + time_monotonic(&tv); + + s = timeout / 1000; + ms = timeout % 1000; + + tv.tv_sec += s; + tv.tv_usec += ms * 1000; + + if (tv.tv_usec > 1000000 /* 1s */) + { + tv.tv_usec -= 1000000; + tv.tv_sec++; + } + return timed_wait_abs(this, lock, tv); +} + +METHOD(rwlock_condvar_t, signal_, void, + private_rwlock_condvar_t *this) +{ + this->mutex->lock(this->mutex); + this->condvar->signal(this->condvar); + this->mutex->unlock(this->mutex); +} + +METHOD(rwlock_condvar_t, broadcast, void, + private_rwlock_condvar_t *this) +{ + this->mutex->lock(this->mutex); + this->condvar->broadcast(this->condvar); + this->mutex->unlock(this->mutex); +} + +METHOD(rwlock_condvar_t, condvar_destroy, void, + private_rwlock_condvar_t *this) +{ + this->condvar->destroy(this->condvar); + this->mutex->destroy(this->mutex); + free(this); +} + +/* + * see header file + */ +rwlock_condvar_t *rwlock_condvar_create() +{ + private_rwlock_condvar_t *this; + + INIT(this, + .public = { + .wait = _wait_, + .timed_wait = _timed_wait, + .timed_wait_abs = _timed_wait_abs, + .signal = _signal_, + .broadcast = _broadcast, + .destroy = _condvar_destroy, + }, + .mutex = mutex_create(MUTEX_TYPE_DEFAULT), + .condvar = condvar_create(CONDVAR_TYPE_DEFAULT), + ); + return &this->public; +} diff --git a/src/libstrongswan/threading/rwlock_condvar.h b/src/libstrongswan/threading/rwlock_condvar.h new file mode 100644 index 000000000..2b40c3fc6 --- /dev/null +++ b/src/libstrongswan/threading/rwlock_condvar.h @@ -0,0 +1,90 @@ +/* + * Copyright (C) 2012 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +/** + * @defgroup rwlock_condvar rwlock_condvar + * @{ @ingroup threading + */ + +#ifndef RWLOCK_CONDVAR_H_ +#define RWLOCK_CONDVAR_H_ + +typedef struct rwlock_condvar_t rwlock_condvar_t; + +#include "rwlock.h" + +/** + * A special condvar implementation that can be used in conjunction + * with rwlock_t (the write lock to be precise). + * + * @note The implementation does not verify that the current thread actually + * holds the write lock and not the read lock, so watch out. + */ +struct rwlock_condvar_t { + + /** + * Wait on a condvar until it gets signalized. + * + * @param lock lock to release while waiting (write lock) + */ + void (*wait)(rwlock_condvar_t *this, rwlock_t *lock); + + /** + * Wait on a condvar until it gets signalized, or times out. + * + * @param lock lock to release while waiting (write lock) + * @param timeout timeout im ms + * @return TRUE if timed out, FALSE otherwise + */ + bool (*timed_wait)(rwlock_condvar_t *this, rwlock_t *lock, u_int timeout); + + /** + * Wait on a condvar until it gets signalized, or times out. + * + * The passed timeval should be calculated based on the time_monotonic() + * function. + * + * @param lock lock to release while waiting (write lock) + * @param tv absolute time until timeout + * @return TRUE if timed out, FALSE otherwise + */ + bool (*timed_wait_abs)(rwlock_condvar_t *this, rwlock_t *lock, + timeval_t tv); + + /** + * Wake up a single thread in a condvar. + */ + void (*signal)(rwlock_condvar_t *this); + + /** + * Wake up all threads in a condvar. + */ + void (*broadcast)(rwlock_condvar_t *this); + + /** + * Destroy a condvar and free its resources. + */ + void (*destroy)(rwlock_condvar_t *this); +}; + +/** + * Create a condvar instance. + * + * @return condvar instance + */ +rwlock_condvar_t *rwlock_condvar_create(); + +#endif /** RWLOCK_CONDVAR_H_ @} */ + diff --git a/src/libstrongswan/threading/semaphore.c b/src/libstrongswan/threading/semaphore.c new file mode 100644 index 000000000..b785ff944 --- /dev/null +++ b/src/libstrongswan/threading/semaphore.c @@ -0,0 +1,179 @@ +/* + * Copyright (C) 2011 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +#include <library.h> + +#if defined(HAVE_CLOCK_GETTIME) && \ + (defined(HAVE_CONDATTR_CLOCK_MONOTONIC) || \ + defined(HAVE_PTHREAD_COND_TIMEDWAIT_MONOTONIC)) +/* if we use MONOTONIC times, we can't use POSIX_SEMAPHORES since they use + * times based on CLOCK_REALTIME */ +#undef HAVE_SEM_TIMEDWAIT +#endif /* HAVE_CLOCK_GETTIME && ... */ + +#ifdef HAVE_SEM_TIMEDWAIT +#include <semaphore.h> +#else /* !HAVE_SEM_TIMEDWAIT */ +#include <threading/condvar.h> +#endif /* HAVE_SEM_TIMEDWAIT */ + +#include "semaphore.h" + +typedef struct private_semaphore_t private_semaphore_t; + +/** + * private data of a semaphore + */ +struct private_semaphore_t { + /** + * public interface + */ + semaphore_t public; + +#ifdef HAVE_SEM_TIMEDWAIT + /** + * wrapped POSIX semaphore object + */ + sem_t sem; +#else /* !HAVE_SEM_TIMEDWAIT */ + + /** + * Mutex to lock count variable + */ + mutex_t *mutex; + + /** + * Condvar to signal count increase + */ + condvar_t *cond; + + /** + * Semaphore count value + */ + u_int count; +#endif /* HAVE_SEM_TIMEDWAIT */ +}; + +METHOD(semaphore_t, wait_, void, + private_semaphore_t *this) +{ +#ifdef HAVE_SEM_TIMEDWAIT + sem_wait(&this->sem); +#else /* !HAVE_SEM_TIMEDWAIT */ + this->mutex->lock(this->mutex); + while (this->count == 0) + { + this->cond->wait(this->cond, this->mutex); + } + this->count--; + this->mutex->unlock(this->mutex); +#endif /* HAVE_SEM_TIMEDWAIT */ +} + +METHOD(semaphore_t, timed_wait_abs, bool, + private_semaphore_t *this, timeval_t tv) +{ +#ifdef HAVE_SEM_TIMEDWAIT + timespec_t ts; + + ts.tv_sec = tv.tv_sec; + ts.tv_nsec = tv.tv_usec * 1000; + + /* there are errors other than ETIMEDOUT possible, but we consider them + * all as timeout */ + return sem_timedwait(&this->sem, &ts) == -1; +#else /* !HAVE_SEM_TIMEDWAIT */ + this->mutex->lock(this->mutex); + while (this->count == 0) + { + if (this->cond->timed_wait_abs(this->cond, this->mutex, tv)) + { + this->mutex->unlock(this->mutex); + return TRUE; + } + } + this->count--; + this->mutex->unlock(this->mutex); + return FALSE; +#endif /* HAVE_SEM_TIMEDWAIT */ +} + +METHOD(semaphore_t, timed_wait, bool, + private_semaphore_t *this, u_int timeout) +{ + timeval_t tv, add; + + add.tv_sec = timeout / 1000; + add.tv_usec = (timeout % 1000) * 1000; + + time_monotonic(&tv); + timeradd(&tv, &add, &tv); + + return timed_wait_abs(this, tv); +} + +METHOD(semaphore_t, post, void, + private_semaphore_t *this) +{ +#ifdef HAVE_SEM_TIMEDWAIT + sem_post(&this->sem); +#else /* !HAVE_SEM_TIMEDWAIT */ + this->mutex->lock(this->mutex); + this->count++; + this->mutex->unlock(this->mutex); + this->cond->signal(this->cond); +#endif /* HAVE_SEM_TIMEDWAIT */ +} + +METHOD(semaphore_t, destroy, void, + private_semaphore_t *this) +{ +#ifdef HAVE_SEM_TIMEDWAIT + sem_destroy(&this->sem); +#else /* !HAVE_SEM_TIMEDWAIT */ + this->cond->destroy(this->cond); + this->mutex->destroy(this->mutex); +#endif /* HAVE_SEM_TIMEDWAIT */ + free(this); +} + +/* + * Described in header + */ +semaphore_t *semaphore_create(u_int value) +{ + private_semaphore_t *this; + + INIT(this, + .public = { + .wait = _wait_, + .timed_wait = _timed_wait, + .timed_wait_abs = _timed_wait_abs, + .post = _post, + .destroy = _destroy, + }, + ); + +#ifdef HAVE_SEM_TIMEDWAIT + sem_init(&this->sem, 0, value); +#else /* !HAVE_SEM_TIMEDWAIT */ + this->mutex = mutex_create(MUTEX_TYPE_DEFAULT); + this->cond = condvar_create(CONDVAR_TYPE_DEFAULT); + this->count = value; +#endif /* HAVE_SEM_TIMEDWAIT */ + + return &this->public; +} + diff --git a/src/libstrongswan/threading/semaphore.h b/src/libstrongswan/threading/semaphore.h new file mode 100644 index 000000000..cdb0a6f19 --- /dev/null +++ b/src/libstrongswan/threading/semaphore.h @@ -0,0 +1,85 @@ +/* + * Copyright (C) 2011 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +/** + * @defgroup semaphore semaphore + * @{ @ingroup threading + */ + +#ifndef THREADING_SEMAPHORE_H_ +#define THREADING_SEMAPHORE_H_ + +typedef struct semaphore_t semaphore_t; + +/** + * A semaphore is basically an integer whose value is never allowed to be + * lower than 0. Two operations can be performed on it: increment the + * value by one, and decrement the value by one. If the value is currently + * zero, then the decrement operation will blcok until the value becomes + * greater than zero. + */ +struct semaphore_t { + + /** + * Decrease the value by one, if it is greater than zero. Otherwise the + * current thread is blocked and it waits until the value increases. + */ + void (*wait)(semaphore_t *this); + + /** + * Decrease the value by one, if it is greater than zero. Otherwise the + * current thread is blocked and it waits until the value increases, or the + * call times out. + * + * @param timeout timeout im ms + * @return TRUE if timed out, FALSE otherwise + */ + bool (*timed_wait)(semaphore_t *this, u_int timeout); + + /** + * Decrease the value by one, if it is greater than zero. Otherwise the + * current thread is blocked and it waits until the value increases, or the + * call times out. + * + * The passed timeval should be calculated based on the time_monotonic() + * function. + * + * @param tv absolute time until timeout + * @return TRUE if timed out, FALSE otherwise + */ + bool (*timed_wait_abs)(semaphore_t *this, timeval_t tv); + + /** + * Increase the value by one. If the value becomes greater than zero, then + * another thread waiting will be woken up. + */ + void (*post)(semaphore_t *this); + + /** + * Destroy a semaphore and free its resources. + */ + void (*destroy)(semaphore_t *this); +}; + +/** + * Create a semaphore instance. + * + * @param value initial value (typically 0) + * @return semaphore instance + */ +semaphore_t *semaphore_create(u_int value); + +#endif /** THREADING_SEMAPHORE_H_ @} */ + diff --git a/src/libstrongswan/threading/spinlock.c b/src/libstrongswan/threading/spinlock.c new file mode 100644 index 000000000..812cf696b --- /dev/null +++ b/src/libstrongswan/threading/spinlock.c @@ -0,0 +1,136 @@ +/* + * Copyright (C) 2012 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +#include <unistd.h> /* for _POSIX_SPIN_LOCKS */ +#include <pthread.h> + +#include <library.h> +#include <debug.h> + +#include "spinlock.h" +#include "mutex.h" +#include "lock_profiler.h" + +#if defined(_POSIX_SPIN_LOCKS) && _POSIX_SPIN_LOCKS == -1 +#undef _POSIX_SPIN_LOCKS +#endif + +typedef struct private_spinlock_t private_spinlock_t; + +/** + * private data + */ +struct private_spinlock_t { + + /** + * public functions + */ + spinlock_t public; + +#ifdef _POSIX_SPIN_LOCKS + + /** + * wrapped pthread spin lock + */ + pthread_spinlock_t spinlock; + + /** + * profiling info, if enabled (the mutex below does profile itself) + */ + lock_profile_t profile; + +#else /* _POSIX_SPIN_LOCKS */ + + /** + * use a mutex if spin locks are not available + */ + mutex_t *mutex; + +#endif /* _POSIX_SPIN_LOCKS */ +}; + +METHOD(spinlock_t, lock, void, + private_spinlock_t *this) +{ +#ifdef _POSIX_SPIN_LOCKS + int err; + + profiler_start(&this->profile); + err = pthread_spin_lock(&this->spinlock); + if (err) + { + DBG1(DBG_LIB, "!!! SPIN LOCK LOCK ERROR: %s !!!", strerror(err)); + } + profiler_end(&this->profile); +#else + this->mutex->lock(this->mutex); +#endif +} + +METHOD(spinlock_t, unlock, void, + private_spinlock_t *this) +{ +#ifdef _POSIX_SPIN_LOCKS + int err; + + err = pthread_spin_unlock(&this->spinlock); + if (err) + { + DBG1(DBG_LIB, "!!! SPIN LOCK UNLOCK ERROR: %s !!!", strerror(err)); + } +#else + this->mutex->unlock(this->mutex); +#endif +} + +METHOD(spinlock_t, destroy, void, + private_spinlock_t *this) +{ +#ifdef _POSIX_SPIN_LOCKS + profiler_cleanup(&this->profile); + pthread_spin_destroy(&this->spinlock); +#else + this->mutex->destroy(this->mutex); +#endif + free(this); +} + +/* + * Described in header + */ +spinlock_t *spinlock_create() +{ + private_spinlock_t *this; + + INIT(this, + .public = { + .lock = _lock, + .unlock = _unlock, + .destroy = _destroy, + }, + ); + +#ifdef _POSIX_SPIN_LOCKS + pthread_spin_init(&this->spinlock, PTHREAD_PROCESS_PRIVATE); + profiler_init(&this->profile); +#else + #warning Using mutexes as spin lock alternatives + this->mutex = mutex_create(MUTEX_TYPE_DEFAULT); +#endif + + return &this->public; +} + + diff --git a/src/libstrongswan/threading/spinlock.h b/src/libstrongswan/threading/spinlock.h new file mode 100644 index 000000000..883980cc2 --- /dev/null +++ b/src/libstrongswan/threading/spinlock.h @@ -0,0 +1,58 @@ +/* + * Copyright (C) 2012 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +/** + * @defgroup spinlock spinlock + * @{ @ingroup threading + */ + +#ifndef THREADING_SPINLOCK_H_ +#define THREADING_SPINLOCK_H_ + +typedef struct spinlock_t spinlock_t; + +/** + * Spin lock wrapper implements a lock with low overhead when the lock is held + * only for a short time (waiting wastes processor cycles, though). + * + * If native spin locks are not available regular mutexes are used as fallback. + */ +struct spinlock_t { + + /** + * Acquire the lock. + */ + void (*lock)(spinlock_t *this); + + /** + * Release the lock. + */ + void (*unlock)(spinlock_t *this); + + /** + * Destroy the instance. + */ + void (*destroy)(spinlock_t *this); +}; + +/** + * Create a spin lock instance. + * + * @return unlocked instance + */ +spinlock_t *spinlock_create(); + +#endif /** THREADING_SPINLOCK_H_ @} */ + diff --git a/src/libstrongswan/threading/thread.c b/src/libstrongswan/threading/thread.c index 49a1b8430..9ef514ebc 100644 --- a/src/libstrongswan/threading/thread.c +++ b/src/libstrongswan/threading/thread.c @@ -114,7 +114,7 @@ typedef struct { /** * Next thread ID. */ -static u_int next_id = 1; +static u_int next_id; /** * Mutex to safely access the next thread ID. @@ -452,6 +452,7 @@ void threads_init() dummy1 = thread_value_create(NULL); + next_id = 1; main_thread->id = 0; main_thread->thread_id = pthread_self(); current_thread = thread_value_create(NULL); @@ -482,4 +483,3 @@ void threads_deinit() current_thread->destroy(current_thread); id_mutex->destroy(id_mutex); } - diff --git a/src/libstrongswan/threading/thread_value.c b/src/libstrongswan/threading/thread_value.c index 3fa70acb2..190b7434f 100644 --- a/src/libstrongswan/threading/thread_value.c +++ b/src/libstrongswan/threading/thread_value.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2009 Tobias Brunner + * Copyright (C) 2009-2012 Tobias Brunner * Hochschule fuer Technik Rapperswil * * This program is free software; you can redistribute it and/or modify it @@ -33,6 +33,11 @@ struct private_thread_value_t { */ pthread_key_t key; + /** + * Destructor to cleanup the value of the thread destroying this object + */ + thread_cleanup_t destructor; + }; METHOD(thread_value_t, set, void, @@ -50,11 +55,22 @@ METHOD(thread_value_t, get, void*, METHOD(thread_value_t, destroy, void, private_thread_value_t *this) { + void *val; + + /* the destructor is not called automatically for the thread calling + * pthread_key_delete() */ + if (this->destructor) + { + val = pthread_getspecific(this->key); + if (val) + { + this->destructor(val); + } + } pthread_key_delete(this->key); free(this); } - /** * Described in header. */ @@ -68,6 +84,7 @@ thread_value_t *thread_value_create(thread_cleanup_t destructor) .get = _get, .destroy = _destroy, }, + .destructor = destructor, ); pthread_key_create(&this->key, destructor); |