void erts_lcnt_lock_opt(erts_lcnt_lock_t *lock, Uint16 option) {
erts_aint_t r_state = 0, w_state = 0;
erts_lcnt_thread_data_t *eltd;
if (erts_lcnt_rt_options & ERTS_LCNT_OPT_SUSPEND) return;
if (!ERTS_LCNT_LOCK_TYPE(lock)) return;
eltd = lcnt_get_thread_data();
ASSERT(eltd);
w_state = ethr_atomic_read(&lock->w_state);
if (option & ERTS_LCNT_LO_WRITE) {
r_state = ethr_atomic_read(&lock->r_state);
ethr_atomic_inc( &lock->w_state);
}
if (option & ERTS_LCNT_LO_READ) {
ethr_atomic_inc( &lock->r_state);
}
/* we cannot acquire w_lock if either w or r are taken */
/* we cannot acquire r_lock if w_lock is taken */
if ((w_state > 0) || (r_state > 0)) {
eltd->lock_in_conflict = 1;
if (eltd->timer_set == 0)
lcnt_time(&eltd->timer);
eltd->timer_set++;
} else {
eltd->lock_in_conflict = 0;
}
}
void *
at_thread(void *unused)
{
int i;
long val, go;
val = ethr_atomic_inc_read(&at_ready);
ASSERT(val > 0);
ASSERT(val <= AT_THREADS);
do {
go = ethr_atomic_read(&at_go);
} while (!go);
for (i = 0; i < AT_ITER; i++) {
val = ethr_atomic_read_bor(&at_data, at_set_val);
ASSERT(val >= (i == 0 ? 0 : at_set_val) + (long) 4711);
ASSERT(val <= at_max_val);
val = ethr_atomic_read_band(&at_data, ~at_rm_val);
ASSERT(val >= at_set_val + (long) 4711);
ASSERT(val <= at_max_val);
val = ethr_atomic_read(&at_data);
ASSERT(val >= at_set_val + (long) 4711);
ASSERT(val <= at_max_val);
val = ethr_atomic_inc_read(&at_data);
ASSERT(val > at_set_val + (long) 4711);
ASSERT(val <= at_max_val);
val = ethr_atomic_dec_read(&at_data);
ASSERT(val >= at_set_val + (long) 4711);
ASSERT(val <= at_max_val);
ethr_atomic_inc(&at_data);
ethr_atomic_dec(&at_data);
val = ethr_atomic_add_read(&at_data, (long) 4711);
ASSERT(val >= at_set_val + (long) 2*4711);
ASSERT(val <= at_max_val);
ethr_atomic_add(&at_data, (long) -4711);
ASSERT(val >= at_set_val + (long) 4711);
ASSERT(val <= at_max_val);
}
ethr_atomic_inc(&at_done);
return NULL;
}
void erts_lcnt_lock(erts_lcnt_lock_t *lock) {
erts_aint_t w_state;
erts_lcnt_thread_data_t *eltd;
if (erts_lcnt_rt_options & ERTS_LCNT_OPT_SUSPEND) return;
if (!ERTS_LCNT_LOCK_TYPE(lock)) return;
w_state = ethr_atomic_read(&lock->w_state);
ethr_atomic_inc( &lock->w_state);
eltd = lcnt_get_thread_data();
ASSERT(eltd);
if (w_state > 0) {
eltd->lock_in_conflict = 1;
/* only set the timer if nobody else has it
* This should only happen when proc_locks aquires several locks
* 'atomicly'. All other locks will block the thread if w_state > 0
* i.e. locked.
*/
if (eltd->timer_set == 0)
lcnt_time(&eltd->timer);
eltd->timer_set++;
} else {
eltd->lock_in_conflict = 0;
}
}
void erts_lcnt_unlock(erts_lcnt_lock_t *lock) {
#ifdef DEBUG
erts_aint_t w_state;
erts_aint_t flowstate;
#endif
if (erts_lcnt_rt_options & ERTS_LCNT_OPT_SUSPEND) return;
#ifdef DEBUG
/* flowstate */
flowstate = ethr_atomic_read(&lock->flowstate);
ASSERT(flowstate == 1);
ethr_atomic_dec( &lock->flowstate);
/* write state */
w_state = ethr_atomic_read(&lock->w_state);
ASSERT(w_state > 0)
#endif
ethr_atomic_dec(&lock->w_state);
}
static void print_lock_x(erts_lcnt_lock_t *lock, Uint16 flag, char *action, char *extra) {
erts_aint_t colls, tries, w_state, r_state;
erts_lcnt_lock_stats_t *stats = NULL;
char *type;
int i;
type = lcnt_lock_type(lock->flag);
r_state = ethr_atomic_read(&lock->r_state);
w_state = ethr_atomic_read(&lock->w_state);
if (lock->flag & flag) {
erts_printf("%20s [%30s] [r/w state %4ld/%4ld] id %T %s\r\n",
action,
lock->name,
r_state,
w_state,
lock->id,
extra);
}
}
void erts_lcnt_lock_post_x(erts_lcnt_lock_t *lock, char *file, unsigned int line) {
erts_lcnt_thread_data_t *eltd;
erts_lcnt_time_t timer;
erts_lcnt_time_t time_wait;
erts_lcnt_lock_stats_t *stats;
#ifdef DEBUG
erts_aint_t flowstate;
#endif
if (erts_lcnt_rt_options & ERTS_LCNT_OPT_SUSPEND) return;
if (!ERTS_LCNT_LOCK_TYPE(lock)) return;
#ifdef DEBUG
if (!(lock->flag & (ERTS_LCNT_LT_RWMUTEX | ERTS_LCNT_LT_RWSPINLOCK))) {
flowstate = ethr_atomic_read(&lock->flowstate);
ASSERT(flowstate == 0);
ethr_atomic_inc( &lock->flowstate);
}
#endif
eltd = lcnt_get_thread_data();
ASSERT(eltd);
/* if lock was in conflict, time it */
if (erts_lcnt_rt_options & ERTS_LCNT_OPT_LOCATION) {
stats = lcnt_get_lock_stats(lock, file, line);
} else {
stats = &lock->stats[0];
}
if (eltd->timer_set) {
lcnt_time(&timer);
lcnt_time_diff(&time_wait, &timer, &(eltd->timer));
lcnt_update_stats(stats, eltd->lock_in_conflict, &time_wait);
eltd->timer_set--;
ASSERT(eltd->timer_set >= 0);
} else {
lcnt_update_stats(stats, eltd->lock_in_conflict, NULL);
}
}
void erts_lcnt_trylock(erts_lcnt_lock_t *lock, int res) {
/* Determine lock_state via res instead of state */
#ifdef DEBUG
erts_aint_t flowstate;
#endif
if (erts_lcnt_rt_options & ERTS_LCNT_OPT_SUSPEND) return;
if (res != EBUSY) {
#ifdef DEBUG
flowstate = ethr_atomic_read(&lock->flowstate);
ASSERT(flowstate == 0);
ethr_atomic_inc( &lock->flowstate);
#endif
ethr_atomic_inc(&lock->w_state);
lcnt_update_stats(&(lock->stats[0]), 0, NULL);
} else {
ethr_atomic_inc(&lock->stats[0].tries);
ethr_atomic_inc(&lock->stats[0].colls);
}
}
static void
atomic_test(void)
{
long data_init, data_final, val;
int res, i;
ethr_tid tid[AT_THREADS];
ethr_thr_opts thr_opts = ETHR_THR_OPTS_DEFAULT_INITER;
atomic_basic_test();
#if ETHR_SIZEOF_PTR > 4
at_rm_val = ((long) 1) << 57;
at_set_val = ((long) 1) << 60;
#else
at_rm_val = ((long) 1) << 27;
at_set_val = ((long) 1) << 30;
#endif
at_max_val = at_set_val + at_rm_val + ((long) AT_THREADS + 1) * 4711;
data_init = at_rm_val + (long) 4711;
data_final = at_set_val + (long) 4711;
thr_opts.detached = 1;
print_line("Initializing");
ethr_atomic_init(&at_ready, 0);
ethr_atomic_init(&at_go, 0);
ethr_atomic_init(&at_done, data_init);
ethr_atomic_init(&at_data, data_init);
val = ethr_atomic_read(&at_data);
ASSERT(val == data_init);
ethr_atomic_set(&at_done, 0);
val = ethr_atomic_read(&at_done);
ASSERT(val == 0);
print_line("Creating threads");
for (i = 0; i < AT_THREADS; i++) {
res = ethr_thr_create(&tid[i], at_thread, NULL, &thr_opts);
ASSERT(res == 0);
}
print_line("Waiting for threads to ready up");
do {
val = ethr_atomic_read(&at_ready);
ASSERT(val >= 0);
ASSERT(val <= AT_THREADS);
} while (val != AT_THREADS);
print_line("Letting threads loose");
val = ethr_atomic_xchg(&at_go, 17);
ASSERT(val == 0);
val = ethr_atomic_read(&at_go);
ASSERT(val == 17);
print_line("Waiting for threads to finish");
do {
val = ethr_atomic_read(&at_done);
ASSERT(val >= 0);
ASSERT(val <= AT_THREADS);
} while (val != AT_THREADS);
print_line("Checking result");
val = ethr_atomic_read(&at_data);
ASSERT(res == 0);
ASSERT(val == data_final);
print_line("Result ok");
}