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() {
75 switch (current_gc->op) {
76 case collect_nursery_op:
77 /* Nursery collection can fail if aging does not have enough
78 free space to fit all live objects from nursery. */
79 current_gc->op = collect_aging_op;
81 case collect_aging_op:
82 /* Aging collection can fail if the aging semispace cannot fit
83 all the live objects from the other aging semispace and the
85 current_gc->op = collect_to_tenured_op;
88 /* Nothing else should fail mid-collection due to insufficient
89 space in the target generation. */
90 critical_error("in start_gc_again, bad GC op", current_gc->op);
95 void factor_vm::set_current_gc_op(gc_op op) {
98 current_gc->event->op = op;
101 void factor_vm::gc(gc_op op, cell requested_size) {
102 FACTOR_ASSERT(!gc_off);
103 FACTOR_ASSERT(!current_gc);
105 /* Important invariant: tenured space must have enough contiguous free
106 space to fit the entire contents of the aging space and nursery. This is
107 because when doing a full collection, objects from younger generations
108 are promoted before any unreachable tenured objects are freed. */
109 FACTOR_ASSERT(!data->high_fragmentation_p());
111 current_gc = new gc_state(op, this);
113 ctx->callstack_seg->set_border_locked(false);
114 atomic::store(¤t_gc_p, true);
116 /* Keep trying to GC higher and higher generations until we don't run
117 out of space in the target generation. */
121 current_gc->event->op = current_gc->op;
123 switch (current_gc->op) {
124 case collect_nursery_op:
127 case collect_aging_op:
128 /* We end up here if the above fails. */
130 if (data->high_fragmentation_p()) {
131 /* Change GC op so that if we fail again, we crash. */
132 set_current_gc_op(collect_full_op);
136 case collect_to_tenured_op:
137 /* We end up here if the above fails. */
138 collect_to_tenured();
139 if (data->high_fragmentation_p()) {
140 /* Change GC op so that if we fail again, we crash. */
141 set_current_gc_op(collect_full_op);
145 case collect_full_op:
148 case collect_compact_op:
151 case collect_growing_heap_op:
152 collect_growing_heap(requested_size);
155 critical_error("in gc, bad GC op", current_gc->op);
161 catch (const must_start_gc_again&) {
162 /* We come back here if the target generation is full. */
170 atomic::store(¤t_gc_p, false);
172 ctx->callstack_seg->set_border_locked(true);
176 /* Check the invariant again, just in case. */
177 FACTOR_ASSERT(!data->high_fragmentation_p());
180 void factor_vm::primitive_minor_gc() {
181 gc(collect_nursery_op, 0);
184 void factor_vm::primitive_full_gc() {
185 gc(collect_full_op, 0);
188 void factor_vm::primitive_compact_gc() {
189 gc(collect_compact_op, 0);
193 * It is up to the caller to fill in the object's fields in a meaningful
196 /* Allocates memory */
197 object* factor_vm::allot_large_object(cell type, cell size) {
198 /* If tenured space does not have enough room, collect and compact */
199 cell requested_size = size + data->high_water_mark();
200 if (!data->tenured->can_allot_p(requested_size)) {
201 primitive_compact_gc();
203 /* If it still won't fit, grow the heap */
204 if (!data->tenured->can_allot_p(requested_size)) {
205 gc(collect_growing_heap_op, size);
209 object* obj = data->tenured->allot(size);
211 /* Allows initialization code to store old->new pointers
212 without hitting the write barrier in the common case of
213 a nursery allocation */
214 write_barrier(obj, size);
216 obj->initialize(type);
220 void factor_vm::primitive_enable_gc_events() {
221 gc_events = new std::vector<gc_event>();
224 /* Allocates memory (byte_array_from_value, result.add) */
225 /* XXX: Remember that growable_array has a data_root already */
226 void factor_vm::primitive_disable_gc_events() {
228 growable_array result(this);
230 std::vector<gc_event>* gc_events = this->gc_events;
231 this->gc_events = NULL;
233 FACTOR_FOR_EACH(*gc_events) {
234 gc_event event = *iter;
235 byte_array* obj = byte_array_from_value(&event);
236 result.add(tag<byte_array>(obj));
240 ctx->push(result.elements.value());
242 delete this->gc_events;
244 ctx->push(false_object);