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Mutex stuff movibg to C

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This commit is contained in:
Vítor Santos Costa
2014-11-27 10:02:04 +00:00
parent c9c2d7233c
commit a83ff038f4
22 changed files with 256 additions and 226 deletions
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183
C/threads.c
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@@ -877,7 +877,11 @@ p_valid_thread( USES_REGS1 )
typedef struct swi_mutex {
UInt owners;
Int tid_own;
MutexEntry *alias;
pthread_mutex_t m;
UInt timestamp;
struct swi_mutex *backbone; // chain of all mutexes
struct swi_mutex *prev, *next; // chain of locked mutexes
} SWIMutex;
static SWIMutex *NewMutex(void) {
@@ -887,21 +891,42 @@ static SWIMutex *NewMutex(void) {
extern int pthread_mutexattr_setkind_np(pthread_mutexattr_t *attr, int kind);
#endif
mutp = (SWIMutex *)Yap_AllocCodeSpace(sizeof(SWIMutex));
if (mutp == NULL) {
return FALSE;
LOCK(GLOBAL_MUT_ACCESS);
mutp = GLOBAL_FreeMutexes;
while (mutp) {
if ((Int)(mutp->owners) < 0) {
// just making sure
break;
}
mutp = mutp->next;
}
pthread_mutexattr_init(&mat);
if (mutp == NULL) {
mutp = (SWIMutex *)Yap_AllocCodeSpace(sizeof(SWIMutex));
if (mutp == NULL) {
UNLOCK(GLOBAL_MUT_ACCESS);
return NULL;
} else {
pthread_mutexattr_init(&mat);
mutp->timestamp = 0;
#if defined(HAVE_PTHREAD_MUTEXATTR_SETKIND_NP) && !defined(__MINGW32__)
pthread_mutexattr_setkind_np(&mat, PTHREAD_MUTEX_RECURSIVE_NP);
pthread_mutexattr_setkind_np(&mat, PTHREAD_MUTEX_RECURSIVE_NP);
#else
#ifdef HAVE_PTHREAD_MUTEXATTR_SETTYPE
pthread_mutexattr_settype(&mat, PTHREAD_MUTEX_RECURSIVE);
pthread_mutexattr_settype(&mat, PTHREAD_MUTEX_RECURSIVE);
#endif
#endif
pthread_mutex_init(&mutp->m, &mat);
pthread_mutex_init(&mutp->m, &mat);
}
mutp->backbone = GLOBAL_mutex_backbone;
GLOBAL_mutex_backbone = mutp;
} else {
// reuse existing mutex
mutp->timestamp++;
}
mutp->owners = 0;
mutp->tid_own = 0;
mutp->tid_own = 0;
mutp->alias = NIL;
UNLOCK(GLOBAL_MUT_ACCESS);
return mutp;
}
@@ -912,10 +937,15 @@ static SWIMutex *MutexOfTerm__(Term t USES_REGS){
SWIMutex *mut = NULL;
if (IsVarTerm(t1)) {
mut = NewMutex();
Yap_unify(MkAddressTerm(mut), ARG1);
} else if (IsIntegerTerm(t1)) {
mut = AddressOfTerm(t1);
Yap_Error(INSTANTIATION_ERROR, t1, "mutex operation");
return NULL;
} else if (IsApplTerm(t1) && FunctorOfTerm(t1) == FunctorMutex) {
mut = AddressOfTerm(ArgOfTerm(1,t1));
if ((Int)(mut->owners) < 0 ||
IntegerOfTerm(ArgOfTerm(2,t1)) != mut->timestamp) {
Yap_Error(EXISTENCE_ERROR_MUTEX, t1, "mutex access");
return NULL;
}
} else if (IsAtomTerm(t1)) {
mut = Yap_GetMutexFromProp(AtomOfTerm(t1));
if (!mut) {
@@ -933,35 +963,53 @@ p_new_mutex( USES_REGS1 ){
SWIMutex* mutp;
Term t1;
if (IsVarTerm((t1 = Deref(ARG1)))) {
Term ts[2];
if (!(mutp = NewMutex()))
return FALSE;
return Yap_unify(ARG1, MkAddressTerm(mutp));
ts[0] = MkAddressTerm(mutp);
ts[1] = MkIntegerTerm(mutp->timestamp);
if (Yap_unify(ARG1, Yap_MkApplTerm(FunctorMutex, 2, ts) ) ) {
return TRUE;
}
Yap_Error(UNINSTANTIATION_ERROR, t1, "mutex_create on an existing mutex");
return FALSE;
} else if(IsAtomTerm(t1)) {
if (!(mutp = NewMutex()))
return FALSE;
return Yap_PutAtomMutex( AtomOfTerm(t1), mutp );
} else if (IsAddressTerm(t1)) {
} else if (IsApplTerm(t1) && FunctorOfTerm(t1) == FunctorMutex) {
Yap_Error(UNINSTANTIATION_ERROR, t1, "mutex_create on an existing mutex");
return FALSE;
}
return FALSE;
}
static Int p_destroy_mutex( USES_REGS1 )
/** @pred mutex_destroy(+ _MutexId_)
Destroy a mutex. After this call, _MutexId_ becomes invalid and
further references yield an `existence_error` exception.
*/
static Int p_destroy_mutex( USES_REGS1 )
{
SWIMutex *mut = MutexOfTerm(Deref(ARG1));
if (!mut)
return FALSE;
if (pthread_mutex_destroy(&mut->m) < 0)
return FALSE;
Yap_FreeCodeSpace((void *)mut);
return FALSE;
if (mut->alias) {
mut->alias->Mutex = NULL;
}
mut->owners = -1;
mut->tid_own = -1;
LOCK(GLOBAL_MUT_ACCESS);
if (GLOBAL_FreeMutexes)
mut->prev = GLOBAL_FreeMutexes->prev;
else
mut->prev = NULL;
mut->next = GLOBAL_FreeMutexes;
GLOBAL_FreeMutexes = mut;
UNLOCK(GLOBAL_MUT_ACCESS);
return TRUE;
}
@@ -976,11 +1024,17 @@ LockMutex( SWIMutex *mut USES_REGS)
#endif
mut->owners++;
mut->tid_own = worker_id;
if (LOCAL_Mutexes)
mut->prev = LOCAL_Mutexes->prev;
else
mut->prev = NULL;
mut->next = LOCAL_Mutexes;
LOCAL_Mutexes = NULL;
return true;
}
static bool
UnLockMutex( SWIMutex *mut )
UnLockMutex( SWIMutex *mut USES_REGS)
{
#if DEBUG_LOCKS
MUTEX_UNLOCK(&mut->m);
@@ -989,9 +1043,39 @@ UnLockMutex( SWIMutex *mut )
return FALSE;
#endif
mut->owners--;
if (mut->prev) {
mut->prev->next = mut->next;
} else {
LOCAL_Mutexes = mut->next;
if (mut->next)
mut->next->prev = NULL;
}
if (mut->next)
mut->next->prev = mut->prev;
return true;
}
/** @pred mutex_lock(+ _MutexId_)
Lock the mutex. Prolog mutexes are <em>recursive</em> mutexes: they
can be locked multiple times by the same thread. Only after unlocking
it as many times as it is locked, the mutex becomes available for
locking by other threads. If another thread has locked the mutex the
calling thread is suspended until to mutex is unlocked.
If _MutexId_ is an atom, and there is no current mutex with that
name, the mutex is created automatically using mutex_create/1. This
implies named mutexes need not be declared explicitly.
Please note that locking and unlocking mutexes should be paired
carefully. Especially make sure to unlock mutexes even if the protected
code fails or raises an exception. For most common cases use
with_mutex/2, which provides a safer way for handling Prolog-level
mutexes.
*/
static Int
p_lock_mutex( USES_REGS1 )
{
@@ -1001,6 +1085,14 @@ p_lock_mutex( USES_REGS1 )
return TRUE;
}
/** @pred mutex_trylock(+ _MutexId_)
As mutex_lock/1, but if the mutex is held by another thread, this
predicates fails immediately.
*/
static Int
p_trylock_mutex( USES_REGS1 )
{
@@ -1015,15 +1107,40 @@ p_trylock_mutex( USES_REGS1 )
return TRUE;
}
/** @pred mutex_unlock(+ _MutexId_)
Unlock the mutex. This can only be called if the mutex is held by the
calling thread. If this is not the case, a `permission_error`
exception is raised.
*/
static Int
p_unlock_mutex( USES_REGS1 )
{
SWIMutex *mut = MutexOfTerm(Deref(ARG1));
if (!mut || !UnLockMutex( mut ))
if (!mut || !UnLockMutex( mut PASS_REGS))
return FALSE;
return TRUE;
}
/** @pred with_mutex(+ _MutexId_, : _Goal_)
Execute _Goal_ while holding _MutexId_. If _Goal_ leaves
choicepoints, these are destroyed (as in once/1). The mutex is unlocked
regardless of whether _Goal_ succeeds, fails or raises an exception.
An exception thrown by _Goal_ is re-thrown after the mutex has been
successfully unlocked. See also `mutex_create/2`.
Although described in the thread-section, this predicate is also
available in the single-threaded version, where it behaves simply as
once/1.
*/
static Int
p_with_mutex( USES_REGS1 )
{
@@ -1084,7 +1201,7 @@ p_with_mutex( USES_REGS1 )
}
end:
excep = Yap_GetException();
if ( !UnLockMutex(mut) ) {
if ( !UnLockMutex(mut PASS_REGS) ) {
return FALSE;
}
if (creeping) {
@@ -1559,11 +1676,11 @@ void Yap_InitThreadPreds(void)
*/
Yap_InitCPred("$valid_thread", 1, p_valid_thread, 0);
Yap_InitCPred("mutex_create", 1, p_new_mutex, SafePredFlag);
Yap_InitCPred("$destroy_mutex", 1, p_destroy_mutex, SafePredFlag);
Yap_InitCPred("$lock_mutex", 1, p_lock_mutex, SafePredFlag);
Yap_InitCPred("$trylock_mutex", 1, p_trylock_mutex, SafePredFlag);
Yap_InitCPred("$unlock_mutex", 1, p_unlock_mutex, SafePredFlag);
Yap_InitCPred("$with_mutex", 2, p_with_mutex, MetaPredFlag);
Yap_InitCPred("mutex_destroy", 1, p_destroy_mutex, SafePredFlag);
Yap_InitCPred("mutex_lock", 1, p_lock_mutex, SafePredFlag);
Yap_InitCPred("mutex_trylock", 1, p_trylock_mutex, SafePredFlag);
Yap_InitCPred("mutex_unlock", 1, p_unlock_mutex, SafePredFlag);
Yap_InitCPred("with_mutex", 2, p_with_mutex, MetaPredFlag);
Yap_InitCPred("$with_with_mutex", 1, p_with_with_mutex, 0);
Yap_InitCPred("$unlock_with_mutex", 1, p_unlock_with_mutex, 0);
Yap_InitCPred("$mutex_info", 3, p_mutex_info, SafePredFlag);