pthread: Avoid crashes/odd behavior caused by spurious wakeups

This is similar to 5152196b2b.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
This commit is contained in:
Derek Buitenhuis 2013-10-18 15:28:51 +01:00
parent 157dc0b489
commit 3511d4fc97
1 changed files with 8 additions and 2 deletions

View File

@ -56,6 +56,7 @@ typedef struct ThreadContext {
pthread_cond_t current_job_cond;
pthread_mutex_t current_job_lock;
int current_job;
unsigned int current_execute;
int done;
} ThreadContext;
@ -64,6 +65,7 @@ static void* attribute_align_arg worker(void *v)
ThreadContext *c = v;
int our_job = c->nb_jobs;
int nb_threads = c->nb_threads;
unsigned int last_execute = 0;
int self_id;
pthread_mutex_lock(&c->current_job_lock);
@ -73,8 +75,9 @@ static void* attribute_align_arg worker(void *v)
if (c->current_job == nb_threads + c->nb_jobs)
pthread_cond_signal(&c->last_job_cond);
if (!c->done)
while (last_execute == c->current_execute && !c->done)
pthread_cond_wait(&c->current_job_cond, &c->current_job_lock);
last_execute = c->current_execute;
our_job = self_id;
if (c->done) {
@ -111,7 +114,8 @@ static void slice_thread_uninit(ThreadContext *c)
static void slice_thread_park_workers(ThreadContext *c)
{
pthread_cond_wait(&c->last_job_cond, &c->current_job_lock);
while (c->current_job != c->nb_threads + c->nb_jobs)
pthread_cond_wait(&c->last_job_cond, &c->current_job_lock);
pthread_mutex_unlock(&c->current_job_lock);
}
@ -138,6 +142,8 @@ static int thread_execute(AVFilterContext *ctx, avfilter_action_func *func,
c->rets = &dummy_ret;
c->nb_rets = 1;
}
c->current_execute++;
pthread_cond_broadcast(&c->current_job_cond);
slice_thread_park_workers(c);