Introduce correct support for compacting GC. (#73)

* Improve size computation.
socketry · Aug 21, 2023 · 5ef599a · 5ef599a
1 parent 7a14eb7
commit 5ef599a
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Showing 6 changed files with 221 additions and 39 deletions.
diff --git a/ext/io/event/selector/array.h b/ext/io/event/selector/array.h
@@ -38,6 +38,12 @@ inline static void IO_Event_Array_allocate(struct IO_Event_Array *array, size_t
 	array->element_size = element_size;
 }
 
+inline static size_t IO_Event_Array_memory_size(const struct IO_Event_Array *array)
+{
+	// Upper bound.
+	return array->count * (sizeof(void*) + array->element_size);
+}
+
 inline static void IO_Event_Array_free(struct IO_Event_Array *array)
 {
 	for (size_t i = 0; i < array->limit; i += 1) {
@@ -117,3 +123,13 @@ inline static void* IO_Event_Array_push(struct IO_Event_Array *array)
 {
 	return IO_Event_Array_lookup(array, array->limit);
 }
+
+inline static void IO_Event_Array_each(struct IO_Event_Array *array, void (*callback)(void*))
+{
+	for (size_t i = 0; i < array->limit; i += 1) {
+		void *element = array->base[i];
+		if (element) {
+			callback(element);
+		}
+	}
+}
diff --git a/ext/io/event/selector/epoll.c b/ext/io/event/selector/epoll.c
@@ -63,10 +63,75 @@ struct IO_Event_Selector_EPoll
 	struct IO_Event_Array descriptors;
 };
 
+// This represents zero or more fibers waiting for a specific descriptor.
+struct IO_Event_Selector_EPoll_Descriptor
+{
+	struct IO_Event_List list;
+
+	// The last IO object that was used to register events.
+	VALUE io;
+
+	// The union of all events we are waiting for:
+	enum IO_Event waiting_events;
+
+	// The union of events we are registered for:
+	enum IO_Event registered_events;
+};
+
+static
+void IO_Event_Selector_EPoll_Waiting_mark(struct IO_Event_List *_waiting)
+{
+	struct IO_Event_Selector_EPoll_Waiting *waiting = (void*)_waiting;
+
+	if (waiting->fiber) {
+		rb_gc_mark_movable(waiting->fiber);
+	}
+}
+
+static
+void IO_Event_Selector_EPoll_Descriptor_mark(void *_descriptor)
+{
+	struct IO_Event_Selector_EPoll_Descriptor *descriptor = _descriptor;
+
+	IO_Event_List_immutable_each(&descriptor->list, IO_Event_Selector_EPoll_Waiting_mark);
+	rb_gc_mark_movable(descriptor->io);
+}
+
+static
 void IO_Event_Selector_EPoll_Type_mark(void *_selector)
 {
 	struct IO_Event_Selector_EPoll *selector = _selector;
+
 	IO_Event_Selector_mark(&selector->backend);
+	IO_Event_Array_each(&selector->descriptors, IO_Event_Selector_EPoll_Descriptor_mark);
+}
+
+static
+void IO_Event_Selector_EPoll_Waiting_compact(struct IO_Event_List *_waiting)
+{
+	struct IO_Event_Selector_EPoll_Waiting *waiting = (void*)_waiting;
+
+	if (waiting->fiber) {
+		waiting->fiber = rb_gc_location(waiting->fiber);
+	}
+}
+
+static
+void IO_Event_Selector_EPoll_Descriptor_compact(void *_descriptor)
+{
+	struct IO_Event_Selector_EPoll_Descriptor *descriptor = _descriptor;
+
+	IO_Event_List_immutable_each(&descriptor->list, IO_Event_Selector_EPoll_Waiting_compact);
+	descriptor->io = rb_gc_location(descriptor->io);
+}
+
+static
+void IO_Event_Selector_EPoll_Type_compact(void *_selector)
+{
+	struct IO_Event_Selector_EPoll *selector = _selector;
+
+	IO_Event_Selector_compact(&selector->backend);
+	IO_Event_Array_each(&selector->descriptors, IO_Event_Selector_EPoll_Descriptor_compact);
 }
 
 static
@@ -79,7 +144,7 @@ void close_internal(struct IO_Event_Selector_EPoll *selector)
 		IO_Event_Interrupt_close(&selector->interrupt);
 	}
 }
-
+static
 void IO_Event_Selector_EPoll_Type_free(void *_selector)
 {
 	struct IO_Event_Selector_EPoll *selector = _selector;
@@ -91,37 +156,28 @@ void IO_Event_Selector_EPoll_Type_free(void *_selector)
 	free(selector);
 }
 
-size_t IO_Event_Selector_EPoll_Type_size(const void *selector)
+static
+size_t IO_Event_Selector_EPoll_Type_size(const void *_selector)
 {
-	return sizeof(struct IO_Event_Selector_EPoll);
+	const struct IO_Event_Selector_EPoll *selector = _selector;
+
+	return sizeof(struct IO_Event_Selector_EPoll)
+		+ IO_Event_Array_memory_size(&selector->descriptors)
+	;
 }
 
 static const rb_data_type_t IO_Event_Selector_EPoll_Type = {
 	.wrap_struct_name = "IO_Event::Backend::EPoll",
 	.function = {
 		.dmark = IO_Event_Selector_EPoll_Type_mark,
+		.dcompact = IO_Event_Selector_EPoll_Type_compact,
 		.dfree = IO_Event_Selector_EPoll_Type_free,
 		.dsize = IO_Event_Selector_EPoll_Type_size,
 	},
 	.data = NULL,
 	.flags = RUBY_TYPED_FREE_IMMEDIATELY,
 };
 
-// This represents zero or more fibers waiting for a specific descriptor.
-struct IO_Event_Selector_EPoll_Descriptor
-{
-	struct IO_Event_List list;
-
-	// The last IO object that was used to register events.
-	VALUE io;
-
-	// The union of all events we are waiting for:
-	enum IO_Event waiting_events;
-
-	// The union of events we are registered for:
-	enum IO_Event registered_events;
-};
-
 inline static
 struct IO_Event_Selector_EPoll_Descriptor * IO_Event_Selector_EPoll_Descriptor_lookup(struct IO_Event_Selector_EPoll *selector, int descriptor)
 {

diff --git a/ext/io/event/selector/kqueue.c b/ext/io/event/selector/kqueue.c
@@ -74,10 +74,71 @@ struct IO_Event_Selector_KQueue
 	struct IO_Event_Array descriptors;
 };
 
+// This represents zero or more fibers waiting for a specific descriptor.
+struct IO_Event_Selector_KQueue_Descriptor
+{
+	struct IO_Event_List list;
+
+	// The union of all events we are waiting for:
+	enum IO_Event waiting_events;
+
+	// The union of events we are registered for:
+	enum IO_Event registered_events;
+
+	// The events that are currently ready:
+	enum IO_Event ready_events;
+};
+
+static
+void IO_Event_Selector_KQueue_Waiting_mark(struct IO_Event_List *_waiting)
+{
+	struct IO_Event_Selector_KQueue_Waiting *waiting = (void*)_waiting;
+
+	if (waiting->fiber) {
+		rb_gc_mark_movable(waiting->fiber);
+	}
+}
+
+static
+void IO_Event_Selector_KQueue_Descriptor_mark(void *_descriptor)
+{
+	struct IO_Event_Selector_KQueue_Descriptor *descriptor = _descriptor;
+
+	IO_Event_List_immutable_each(&descriptor->list, IO_Event_Selector_KQueue_Waiting_mark);
+}
+
+static
 void IO_Event_Selector_KQueue_Type_mark(void *_selector)
 {
 	struct IO_Event_Selector_KQueue *selector = _selector;
 	IO_Event_Selector_mark(&selector->backend);
+	IO_Event_Array_each(&selector->descriptors, IO_Event_Selector_KQueue_Descriptor_mark);
+}
+
+static
+void IO_Event_Selector_KQueue_Waiting_compact(struct IO_Event_List *_waiting)
+{
+	struct IO_Event_Selector_KQueue_Waiting *waiting = (void*)_waiting;
+
+	if (waiting->fiber) {
+		rb_gc_location(waiting->fiber);
+	}
+}
+
+static
+void IO_Event_Selector_KQueue_Descriptor_compact(void *_descriptor)
+{
+	struct IO_Event_Selector_KQueue_Descriptor *descriptor = _descriptor;
+
+	IO_Event_List_immutable_each(&descriptor->list, IO_Event_Selector_KQueue_Waiting_compact);
+}
+
+static
+void IO_Event_Selector_KQueue_Type_compact(void *_selector)
+{
+	struct IO_Event_Selector_KQueue *selector = _selector;
+	IO_Event_Selector_compact(&selector->backend);
+	IO_Event_Array_each(&selector->descriptors, IO_Event_Selector_KQueue_Descriptor_compact);
 }
 
 static
@@ -89,6 +150,7 @@ void close_internal(struct IO_Event_Selector_KQueue *selector)
 	}
 }
 
+static
 void IO_Event_Selector_KQueue_Type_free(void *_selector)
 {
 	struct IO_Event_Selector_KQueue *selector = _selector;
@@ -100,37 +162,28 @@ void IO_Event_Selector_KQueue_Type_free(void *_selector)
 	free(selector);
 }
 
-size_t IO_Event_Selector_KQueue_Type_size(const void *selector)
+static
+size_t IO_Event_Selector_KQueue_Type_size(const void *_selector)
 {
-	return sizeof(struct IO_Event_Selector_KQueue);
+	const struct IO_Event_Selector_KQueue *selector = _selector;
+
+	return sizeof(struct IO_Event_Selector_KQueue)
+		+ IO_Event_Array_memory_size(&selector->descriptors)
+	;
 }
 
 static const rb_data_type_t IO_Event_Selector_KQueue_Type = {
 	.wrap_struct_name = "IO_Event::Backend::KQueue",
 	.function = {
 		.dmark = IO_Event_Selector_KQueue_Type_mark,
+		.dcompact = IO_Event_Selector_KQueue_Type_compact,
 		.dfree = IO_Event_Selector_KQueue_Type_free,
 		.dsize = IO_Event_Selector_KQueue_Type_size,
 	},
 	.data = NULL,
 	.flags = RUBY_TYPED_FREE_IMMEDIATELY,
 };
 
-// This represents zero or more fibers waiting for a specific descriptor.
-struct IO_Event_Selector_KQueue_Descriptor
-{
-	struct IO_Event_List list;
-
-	// The union of all events we are waiting for:
-	enum IO_Event waiting_events;
-
-	// The union of events we are registered for:
-	enum IO_Event registered_events;
-
-	// The events that are currently ready:
-	enum IO_Event ready_events;
-};
-
 inline static
 struct IO_Event_Selector_KQueue_Descriptor * IO_Event_Selector_KQueue_Descriptor_lookup(struct IO_Event_Selector_KQueue *selector, uintptr_t descriptor)
 {

diff --git a/ext/io/event/selector/list.h b/ext/io/event/selector/list.h
@@ -69,3 +69,14 @@ inline static int IO_Event_List_empty(struct IO_Event_List *list)
 {
 	return list->head == list->tail;
 }
+
+inline static void IO_Event_List_immutable_each(struct IO_Event_List *list, void (*callback)(struct IO_Event_List *node))
+{
+	struct IO_Event_List *node = list->tail;
+
+	while (node != list) {
+		callback(node);
+
+		node = node->tail;
+	}
+}
diff --git a/ext/io/event/selector/selector.h b/ext/io/event/selector/selector.h
@@ -109,11 +109,22 @@ void IO_Event_Selector_initialize(struct IO_Event_Selector *backend, VALUE loop)
 
 static inline
 void IO_Event_Selector_mark(struct IO_Event_Selector *backend) {
-	rb_gc_mark(backend->loop);
+	rb_gc_mark_movable(backend->loop);
 
 	struct IO_Event_Selector_Queue *ready = backend->ready;
 	while (ready) {
-		rb_gc_mark(ready->fiber);
+		rb_gc_mark_movable(ready->fiber);
+		ready = ready->behind;
+	}
+}
+
+static inline
+void IO_Event_Selector_compact(struct IO_Event_Selector *backend) {
+	backend->loop = rb_gc_location(backend->loop);
+
+	struct IO_Event_Selector_Queue *ready = backend->ready;
+	while (ready) {
+		ready->fiber = rb_gc_location(ready->fiber);
 		ready = ready->behind;
 	}
 }

diff --git a/ext/io/event/selector/uring.c b/ext/io/event/selector/uring.c
@@ -75,10 +75,38 @@ struct IO_Event_Selector_URing_Completion
 	struct IO_Event_Selector_URing_Waiting *waiting;
 };
 
+static
+void IO_Event_Selector_URing_Completion_mark(void *_completion)
+{
+	struct IO_Event_Selector_URing_Completion *completion = _completion;
+
+	if (completion->waiting) {
+		rb_gc_mark_movable(completion->waiting->fiber);
+	}
+}
+
 void IO_Event_Selector_URing_Type_mark(void *_selector)
 {
 	struct IO_Event_Selector_URing *selector = _selector;
 	IO_Event_Selector_mark(&selector->backend);
+	IO_Event_Array_each(&selector->completions, IO_Event_Selector_URing_Completion_mark);
+}
+
+static
+void IO_Event_Selector_URing_Completion_compact(void *_completion)
+{
+	struct IO_Event_Selector_URing_Completion *completion = _completion;
+
+	if (completion->waiting) {
+		completion->waiting->fiber = rb_gc_location(completion->waiting->fiber);
+	}
+}
+
+void IO_Event_Selector_URing_Type_compact(void *_selector)
+{
+	struct IO_Event_Selector_URing *selector = _selector;
+	IO_Event_Selector_compact(&selector->backend);
+	IO_Event_Array_each(&selector->completions, IO_Event_Selector_URing_Completion_compact);
 }
 
 static
@@ -90,6 +118,7 @@ void close_internal(struct IO_Event_Selector_URing *selector)
 	}
 }
 
+static
 void IO_Event_Selector_URing_Type_free(void *_selector)
 {
 	struct IO_Event_Selector_URing *selector = _selector;
@@ -101,15 +130,21 @@ void IO_Event_Selector_URing_Type_free(void *_selector)
 	free(selector);
 }
 
-size_t IO_Event_Selector_URing_Type_size(const void *selector)
+static
+size_t IO_Event_Selector_URing_Type_size(const void *_selector)
 {
-	return sizeof(struct IO_Event_Selector_URing);
+	const struct IO_Event_Selector_URing *selector = _selector;
+
+	return sizeof(struct IO_Event_Selector_URing)
+		+ IO_Event_Array_memory_size(&selector->completions)
+	;
 }
 
 static const rb_data_type_t IO_Event_Selector_URing_Type = {
 	.wrap_struct_name = "IO_Event::Backend::URing",
 	.function = {
 		.dmark = IO_Event_Selector_URing_Type_mark,
+		.dcompact = IO_Event_Selector_URing_Type_compact,
 		.dfree = IO_Event_Selector_URing_Type_free,
 		.dsize = IO_Event_Selector_URing_Type_size,
 	},