#include "mono/sgen/sgen-client.h"
static int workers_num;
+static int active_workers_num;
static volatile gboolean forced_stop;
static WorkerData *workers_data;
static SgenWorkerCallback worker_init_cb;
* gracefully finished, so it can restart them.
*/
static mono_mutex_t finished_lock;
+static volatile gboolean workers_finished;
+static int worker_awakenings;
static SgenSectionGrayQueue workers_distribute_gray_queue;
static gboolean workers_distribute_gray_queue_inited;
typedef gint32 State;
static SgenObjectOperations * volatile idle_func_object_ops;
+static SgenObjectOperations *idle_func_object_ops_par, *idle_func_object_ops_nopar;
/*
* finished_callback is called only when the workers finish work normally (when they
* are not forced to finish). The callback is used to enqueue preclean jobs.
int i;
gboolean need_signal = FALSE;
- for (i = 0; i < workers_num; i++) {
+ /*
+ * All workers are awaken, make sure we reset the parallel context.
+ * We call this function only when starting the workers so nobody is running,
+ * or when the last worker is enqueuing preclean work. In both cases we can't
+ * have a worker working using a nopar context, which means it is safe.
+ */
+ idle_func_object_ops = (active_workers_num > 1) ? idle_func_object_ops_par : idle_func_object_ops_nopar;
+ workers_finished = FALSE;
+
+ for (i = 0; i < active_workers_num; i++) {
State old_state;
gboolean did_set_state;
mono_os_mutex_lock (&finished_lock);
- for (i = 0; i < workers_num; i++) {
+ for (i = 0; i < active_workers_num; i++) {
if (state_is_working_or_enqueued (workers_data [i].state))
working++;
}
if (working == 1) {
SgenWorkersFinishCallback callback = finish_callback;
+ SGEN_ASSERT (0, idle_func_object_ops == idle_func_object_ops_nopar, "Why are we finishing with parallel context");
/* We are the last one left. Enqueue preclean job if we have one and awake everybody */
SGEN_ASSERT (0, data->state != STATE_NOT_WORKING, "How did we get from doing idle work to NOT WORKING without setting it ourselves?");
if (callback) {
finish_callback = NULL;
callback ();
+ worker_awakenings = 0;
/* Make sure each worker has a chance of seeing the enqueued jobs */
sgen_workers_ensure_awake ();
SGEN_ASSERT (0, data->state == STATE_WORK_ENQUEUED, "Why did we fail to set our own state to ENQUEUED");
SGEN_ASSERT (0, old_state == STATE_WORKING, "What other possibility is there?");
} while (!set_state (data, old_state, STATE_NOT_WORKING));
+ /*
+ * If we are second to last to finish, we set the scan context to the non-parallel
+ * version so we can speed up the last worker. This helps us maintain same level
+ * of performance as non-parallel mode even if we fail to distribute work properly.
+ */
+ if (working == 2)
+ idle_func_object_ops = idle_func_object_ops_nopar;
+
+ workers_finished = TRUE;
mono_os_mutex_unlock (&finished_lock);
binary_protocol_worker_finish (sgen_timestamp (), forced_stop);
sgen_thread_pool_job_enqueue (job);
}
-void
-sgen_workers_wait_for_jobs_finished (void)
-{
- sgen_thread_pool_wait_for_all_jobs ();
- /*
- * If the idle task was never triggered or it finished before the last job did and
- * then didn't get triggered again, we might end up in the situation of having
- * something in the gray queue yet the idle task not working. The easiest way to
- * make sure this doesn't stay that way is to just trigger it again after all jobs
- * have finished.
- */
- sgen_workers_ensure_awake ();
-}
-
static gboolean
workers_get_work (WorkerData *data)
{
if (major->is_concurrent) {
GrayQueueSection *section = sgen_section_gray_queue_dequeue (&workers_distribute_gray_queue);
if (section) {
- sgen_gray_object_enqueue_section (&data->private_gray_queue, section);
+ sgen_gray_object_enqueue_section (&data->private_gray_queue, section, major->is_parallel);
return TRUE;
}
}
return FALSE;
}
+static gboolean
+workers_steal_work (WorkerData *data)
+{
+ SgenMajorCollector *major = sgen_get_major_collector ();
+ GrayQueueSection *section = NULL;
+ int i, current_worker;
+
+ if (!major->is_parallel)
+ return FALSE;
+
+ /* If we're parallel, steal from other workers' private gray queues */
+ g_assert (sgen_gray_object_queue_is_empty (&data->private_gray_queue));
+
+ current_worker = (int) (data - workers_data);
+
+ for (i = 1; i < active_workers_num && !section; i++) {
+ int steal_worker = (current_worker + i) % active_workers_num;
+ if (state_is_working_or_enqueued (workers_data [steal_worker].state))
+ section = sgen_gray_object_steal_section (&workers_data [steal_worker].private_gray_queue);
+ }
+
+ if (section) {
+ sgen_gray_object_enqueue_section (&data->private_gray_queue, section, TRUE);
+ return TRUE;
+ }
+
+ /* Nobody to steal from */
+ g_assert (sgen_gray_object_queue_is_empty (&data->private_gray_queue));
+ return FALSE;
+}
+
static void
concurrent_enqueue_check (GCObject *obj)
{
}
}
+static gboolean
+should_work_func (void *data_untyped)
+{
+ WorkerData *data = (WorkerData*)data_untyped;
+ int current_worker = (int) (data - workers_data);
+
+ return current_worker < active_workers_num;
+}
+
static void
marker_idle_func (void *data_untyped)
{
SGEN_ASSERT (0, data->state != STATE_NOT_WORKING, "How did we get from WORK ENQUEUED to NOT WORKING?");
}
- if (!forced_stop && (!sgen_gray_object_queue_is_empty (&data->private_gray_queue) || workers_get_work (data))) {
+ if (!forced_stop && (!sgen_gray_object_queue_is_empty (&data->private_gray_queue) || workers_get_work (data) || workers_steal_work (data))) {
ScanCopyContext ctx = CONTEXT_FROM_OBJECT_OPERATIONS (idle_func_object_ops, &data->private_gray_queue);
SGEN_ASSERT (0, !sgen_gray_object_queue_is_empty (&data->private_gray_queue), "How is our gray queue empty if we just got work?");
sgen_drain_gray_stack (ctx);
+
+ if (data->private_gray_queue.num_sections > 16 && workers_finished && worker_awakenings < active_workers_num) {
+ /* We bound the number of worker awakenings just to be sure */
+ worker_awakenings++;
+ sgen_workers_ensure_awake ();
+ }
} else {
worker_try_finish (data);
}
void **workers_data_ptrs = (void **)alloca(num_workers * sizeof(void *));
if (!sgen_get_major_collector ()->is_concurrent) {
- sgen_thread_pool_init (num_workers, thread_pool_init_func, NULL, NULL, NULL);
+ sgen_thread_pool_init (num_workers, thread_pool_init_func, NULL, NULL, NULL, NULL);
return;
}
//g_print ("initing %d workers\n", num_workers);
workers_num = num_workers;
+ active_workers_num = num_workers;
workers_data = (WorkerData *)sgen_alloc_internal_dynamic (sizeof (WorkerData) * num_workers, INTERNAL_MEM_WORKER_DATA, TRUE);
memset (workers_data, 0, sizeof (WorkerData) * num_workers);
worker_init_cb = callback;
- sgen_thread_pool_init (num_workers, thread_pool_init_func, marker_idle_func, continue_idle_func, workers_data_ptrs);
+ sgen_thread_pool_init (num_workers, thread_pool_init_func, marker_idle_func, continue_idle_func, should_work_func, workers_data_ptrs);
mono_counters_register ("# workers finished", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_workers_num_finished);
}
}
void
-sgen_workers_start_all_workers (SgenObjectOperations *object_ops, SgenWorkersFinishCallback callback)
+sgen_workers_set_num_active_workers (int num_workers)
{
+ if (num_workers) {
+ SGEN_ASSERT (0, active_workers_num <= workers_num, "We can't start more workers than we initialized");
+ active_workers_num = num_workers;
+ } else {
+ active_workers_num = workers_num;
+ }
+}
+
+void
+sgen_workers_start_all_workers (SgenObjectOperations *object_ops_nopar, SgenObjectOperations *object_ops_par, SgenWorkersFinishCallback callback)
+{
+ idle_func_object_ops_par = object_ops_par;
+ idle_func_object_ops_nopar = object_ops_nopar;
forced_stop = FALSE;
- idle_func_object_ops = object_ops;
finish_callback = callback;
+ worker_awakenings = 0;
mono_memory_write_barrier ();
sgen_workers_ensure_awake ();
/* At this point all the workers have stopped. */
SGEN_ASSERT (0, sgen_section_gray_queue_is_empty (&workers_distribute_gray_queue), "Why is there still work left to do?");
- for (i = 0; i < workers_num; ++i)
+ for (i = 0; i < active_workers_num; ++i)
SGEN_ASSERT (0, sgen_gray_object_queue_is_empty (&workers_data [i].private_gray_queue), "Why is there still work left to do?");
}
if (!sgen_section_gray_queue_is_empty (&workers_distribute_gray_queue))
return TRUE;
- for (i = 0; i < workers_num; ++i) {
+ for (i = 0; i < active_workers_num; ++i) {
if (!sgen_gray_object_queue_is_empty (&workers_data [i].private_gray_queue))
return TRUE;
}
{
int i;
- for (i = 0; i < workers_num; i++) {
+ for (i = 0; i < active_workers_num; i++) {
if (state_is_working_or_enqueued (workers_data [i].state))
return FALSE;
}
}
void
-sgen_workers_take_from_queue_and_awake (SgenGrayQueue *queue)
+sgen_workers_take_from_queue (SgenGrayQueue *queue)
{
- gboolean wake = FALSE;
+ sgen_gray_object_spread (queue, sgen_workers_get_job_split_count ());
for (;;) {
GrayQueueSection *section = sgen_gray_object_dequeue_section (queue);
if (!section)
break;
sgen_section_gray_queue_enqueue (&workers_distribute_gray_queue, section);
- wake = TRUE;
}
- if (wake) {
- SGEN_ASSERT (0, sgen_concurrent_collection_in_progress (), "Why is there work to take when there's no concurrent collection in progress?");
- sgen_workers_ensure_awake ();
- }
+ SGEN_ASSERT (0, !sgen_workers_are_working (), "We should fully populate the distribute gray queue before we start the workers");
}
SgenObjectOperations*
sgen_workers_get_idle_func_object_ops (void)
{
- return idle_func_object_ops;
+ return (idle_func_object_ops_par) ? idle_func_object_ops_par : idle_func_object_ops_nopar;
}
/*
int
sgen_workers_get_job_split_count (void)
{
- return (workers_num > 1) ? workers_num * 4 : 1;
+ return (active_workers_num > 1) ? active_workers_num * 4 : 1;
}
void
projects / mono.git / blobdiff