5 gc_event::gc_event(gc_op op, factor_vm* parent)
9 code_blocks_scanned(0),
10 start_time(nano_count()),
16 data_heap_before = parent->data_room();
17 code_heap_before = parent->code->allocator->as_allocator_room();
18 start_time = nano_count();
21 void gc_event::reset_timer() { temp_time = nano_count(); }
23 void gc_event::ended_card_scan(cell cards_scanned_, cell decks_scanned_) {
24 cards_scanned += cards_scanned_;
25 decks_scanned += decks_scanned_;
26 card_scan_time = (cell)(nano_count() - temp_time);
29 void gc_event::ended_code_scan(cell code_blocks_scanned_) {
30 code_blocks_scanned += code_blocks_scanned_;
31 code_scan_time = (cell)(nano_count() - temp_time);
34 void gc_event::ended_data_sweep() {
35 data_sweep_time = (cell)(nano_count() - temp_time);
38 void gc_event::ended_code_sweep() {
39 code_sweep_time = (cell)(nano_count() - temp_time);
42 void gc_event::ended_compaction() {
43 compaction_time = (cell)(nano_count() - temp_time);
46 void gc_event::ended_gc(factor_vm* parent) {
47 data_heap_after = parent->data_room();
48 code_heap_after = parent->code->allocator->as_allocator_room();
49 total_time = (cell)(nano_count() - start_time);
52 gc_state::gc_state(gc_op op, factor_vm* parent) : op(op) {
53 if (parent->gc_events) {
54 event = new gc_event(op, parent);
55 start_time = nano_count();
60 gc_state::~gc_state() {
67 void factor_vm::end_gc() {
69 current_gc->event->ended_gc(this);
70 gc_events->push_back(*current_gc->event);
74 void factor_vm::start_gc_again() {
77 switch (current_gc->op) {
78 case collect_nursery_op:
79 /* Nursery collection can fail if aging does not have enough
80 free space to fit all live objects from nursery. */
81 current_gc->op = collect_aging_op;
83 case collect_aging_op:
84 /* Aging collection can fail if the aging semispace cannot fit
85 all the live objects from the other aging semispace and the
87 current_gc->op = collect_to_tenured_op;
90 /* Nothing else should fail mid-collection due to insufficient
91 space in the target generation. */
92 critical_error("in start_gc_again, bad GC op", current_gc->op);
97 current_gc->event = new gc_event(current_gc->op, this);
100 void factor_vm::set_current_gc_op(gc_op op) {
103 current_gc->event->op = op;
106 void factor_vm::gc(gc_op op, cell requested_size) {
107 FACTOR_ASSERT(!gc_off);
108 FACTOR_ASSERT(!current_gc);
110 /* Important invariant: tenured space must have enough contiguous free
111 space to fit the entire contents of the aging space and nursery. This is
112 because when doing a full collection, objects from younger generations
113 are promoted before any unreachable tenured objects are freed. */
114 FACTOR_ASSERT(!data->high_fragmentation_p());
116 current_gc = new gc_state(op, this);
118 ctx->callstack_seg->set_border_locked(false);
119 atomic::store(¤t_gc_p, true);
121 /* Keep trying to GC higher and higher generations until we don't run
122 out of space in the target generation. */
126 current_gc->event->op = current_gc->op;
128 switch (current_gc->op) {
129 case collect_nursery_op:
132 case collect_aging_op:
133 /* We end up here if the above fails. */
135 if (data->high_fragmentation_p()) {
136 /* Change GC op so that if we fail again, we crash. */
137 set_current_gc_op(collect_full_op);
141 case collect_to_tenured_op:
142 /* We end up here if the above fails. */
143 collect_to_tenured();
144 if (data->high_fragmentation_p()) {
145 /* Change GC op so that if we fail again, we crash. */
146 set_current_gc_op(collect_full_op);
150 case collect_full_op:
153 case collect_compact_op:
156 case collect_growing_heap_op:
157 collect_growing_heap(requested_size);
160 critical_error("in gc, bad GC op", current_gc->op);
166 catch (const must_start_gc_again&) {
167 /* We come back here if the target generation is full. */
175 atomic::store(¤t_gc_p, false);
177 ctx->callstack_seg->set_border_locked(true);
181 /* Check the invariant again, just in case. */
182 FACTOR_ASSERT(!data->high_fragmentation_p());
185 void factor_vm::primitive_minor_gc() {
186 gc(collect_nursery_op, 0);
189 void factor_vm::primitive_full_gc() {
190 gc(collect_full_op, 0);
193 void factor_vm::primitive_compact_gc() {
194 gc(collect_compact_op, 0);
198 * It is up to the caller to fill in the object's fields in a meaningful
201 /* Allocates memory */
202 object* factor_vm::allot_large_object(cell type, cell size) {
203 /* If tenured space does not have enough room, collect and compact */
204 cell requested_size = size + data->high_water_mark();
205 if (!data->tenured->can_allot_p(requested_size)) {
206 primitive_compact_gc();
208 /* If it still won't fit, grow the heap */
209 if (!data->tenured->can_allot_p(requested_size)) {
210 gc(collect_growing_heap_op, size);
214 object* obj = data->tenured->allot(size);
216 /* Allows initialization code to store old->new pointers
217 without hitting the write barrier in the common case of
218 a nursery allocation */
219 write_barrier(obj, size);
221 obj->initialize(type);
225 void factor_vm::primitive_enable_gc_events() {
226 gc_events = new std::vector<gc_event>();
229 /* Allocates memory (byte_array_from_value, result.add) */
230 /* XXX: Remember that growable_array has a data_root already */
231 void factor_vm::primitive_disable_gc_events() {
233 growable_array result(this);
235 std::vector<gc_event>* gc_events = this->gc_events;
236 this->gc_events = NULL;
238 FACTOR_FOR_EACH(*gc_events) {
239 gc_event event = *iter;
240 byte_array* obj = byte_array_from_value(&event);
241 result.add(tag<byte_array>(obj));
245 ctx->push(result.elements.value());
247 delete this->gc_events;
249 ctx->push(false_object);