void connection_consumer_start(void *arg)
{
int rc;
struct server_ctx *ctx;
uv_loop_t* loop;
ctx = arg;
loop = uv_loop_new();
listener_event_loops[ctx->index] = *loop;
http_request_cache_configure_listener(loop, &listener_async_handles[ctx->index]);
uv_barrier_wait(listeners_created_barrier);
rc = uv_async_init(loop, &ctx->async_handle, connection_consumer_close);
uv_unref((uv_handle_t*) &ctx->async_handle);
/* Wait until the main thread is ready. */
uv_sem_wait(&ctx->semaphore);
get_listen_handle(loop, (uv_stream_t*) &ctx->server_handle);
uv_sem_post(&ctx->semaphore);
rc = uv_listen((uv_stream_t*)&ctx->server_handle, 128, connection_consumer_new_connection);
rc = uv_run(loop, UV_RUN_DEFAULT);
uv_loop_delete(loop);
}
static PyObject *
Barrier_func_wait(Barrier *self)
{
RAISE_IF_NOT_INITIALIZED(self, NULL);
Py_BEGIN_ALLOW_THREADS
uv_barrier_wait(&self->uv_barrier);
Py_END_ALLOW_THREADS
Py_RETURN_NONE;
}
static void thread_main(void* arg) {
struct thread_ctx* ctx;
char buf[4096];
ssize_t n;
ctx = arg;
uv_barrier_wait(&ctx->barrier);
do
n = read(ctx->fd, buf, sizeof(buf));
while (n > 0 || (n == -1 && errno == EINTR));
ASSERT(n == 0);
}
void reader(void *n)
{
int num = *(int*)n;
int i;
for (i = 0; i < 20; ++i)
{
uv_rwlock_rdlock(&numlock);
printf("Reader %d: acquired lock\n", num);
printf("Reader %d: shared num = %d\n", num, shared_num);
uv_rwlock_rdunlock(&numlock);
printf("Reader %d: released lock\n", num);
}
uv_barrier_wait(&blocker);
}
void writer(void *n)
{
int num = *(int*)n;
int i;
for (i = 0; i < 20; ++i)
{
uv_rwlock_wrlock(&numlock);
printf("Writer %d: acquired lock\n", num);
shared_num++;
printf("Writer %d: incremented shared num = %d\n", num, shared_num);
uv_rwlock_wrunlock(&numlock);
printf("Writer %d: released lock\n", num);
}
uv_barrier_wait(&blocker);
}
// https://github.com/thlorenz/libuv-dox/blob/master/methods.md#uv_rwlock_wrlock
void writer_entry(void *n) {
int r;
int num = *(int*)n;
for (int i = 0; i < ROUNDS; i++) {
do {
r = uv_rwlock_trywrlock(&numlock);
// see: reader_entry
if (r && r != -EBUSY && r != -EAGAIN) ERROR("obtaining write lock", r);
} while(r);
fprintf(stderr, "Writer %d: aquired lock\n", num);
shared_num++;
fprintf(stderr, "Writer %d: incremented shared num = %d\n", num, shared_num);
uv_rwlock_wrunlock(&numlock);
fprintf(stderr, "Writer %d: released lock\n", num);
}
uv_barrier_wait(&blocker);
}
int main()
{
uv_thread_t threads[3];
int thread_nums[] = {1, 2, 1};
uv_barrier_init(&blocker, 4);
shared_num = 0;
uv_rwlock_init(&numlock);
uv_thread_create(&threads[0], reader, &thread_nums[0]);
uv_thread_create(&threads[1], reader, &thread_nums[1]);
uv_thread_create(&threads[2], writer, &thread_nums[2]);
uv_barrier_wait(&blocker);
uv_barrier_destroy(&blocker);
uv_rwlock_destroy(&numlock);
return 0;
}
// https://github.com/thlorenz/libuv-dox/blob/master/methods.md#uv_rwlock_rdlock
void reader_entry(void *n) {
int r;
int num = *(int*)n;
for (int i = 0; i < ROUNDS; i++) {
do {
r = uv_rwlock_tryrdlock(&numlock);
// implementation ./src/unix/thread.c aborts the process unless return value was EBUSY or EAGAIN
// so checking here again is redundant and mainly done for documentation
// fact is that the only r we'd ever get would be EBUSY or EAGAIN (negated)
if (r && r != -EBUSY && r != -EAGAIN) ERROR("obtaining read lock", r);
} while(r);
fprintf(stderr, "Reader %d: aquired lock and shared num = %d\n", num, shared_num);
uv_rwlock_rdunlock(&numlock);
fprintf(stderr, "Reader %d: released lock\n", num);
}
uv_barrier_wait(&blocker);
}
// thread function: used by all except the main thread
void jl_threadfun(void *arg)
{
jl_threadarg_t *targ = (jl_threadarg_t*)arg;
// initialize this thread (set tid, create heap, set up root task)
jl_init_threadtls(targ->tid);
void *stack_lo, *stack_hi;
jl_init_stack_limits(0, &stack_lo, &stack_hi);
jl_init_root_task(stack_lo, stack_hi);
jl_ptls_t ptls = jl_get_ptls_states();
jl_gc_state_set(ptls, JL_GC_STATE_SAFE, 0);
uv_barrier_wait(targ->barrier);
// free the thread argument here
free(targ);
(void)jl_gc_unsafe_enter(ptls);
jl_current_task->exception = jl_nothing;
jl_finish_task(jl_current_task, jl_nothing); // noreturn
}
// same as ./10-locks, but using try* functions when obtaining read and write locks
//
int main() {
int r;
const int count = 4;
fprintf(stderr, "barrier: init\n");
uv_barrier_init(&blocker, count);
shared_num = 0;
// https://github.com/thlorenz/libuv-dox/blob/master/methods.md#rwlock
fprintf(stderr, "rwlock: init\n");
r = uv_rwlock_init(&numlock);
if (r) ERROR("rwlock_init", r);
uv_thread_t threads[3];
int thread_nums[] = { 1, 2, 1 };
r = uv_thread_create(&threads[0], reader_entry, &thread_nums[0]);
if (r) ERROR("thread_create", r);
r = uv_thread_create(&threads[1], reader_entry, &thread_nums[1]);
if (r) ERROR("thread_create", r);
r = uv_thread_create(&threads[2], writer_entry, &thread_nums[2]);
if (r) ERROR("thread_create", r);
// https://github.com/thlorenz/libuv-dox/blob/master/methods.md#barrier
fprintf(stderr, "barrier: wait\n");
uv_barrier_wait(&blocker);
fprintf(stderr, "barrier: destroy\n");
uv_barrier_destroy(&blocker);
fprintf(stderr, "rwlock: destroy\n");
uv_rwlock_destroy(&numlock);
if (r) ERROR("rwlock_destroy", r);
return 0;
}
static mrb_value
mrb_uv_barrier_wait(mrb_state *mrb, mrb_value self)
{
uv_barrier_wait((uv_barrier_t*)mrb_uv_get_ptr(mrb, self, &barrier_type));
return self;
}
