vm/gc.cpp

   1 #include "master.hpp"
   2
   3 namespace factor
   4 {
   5
   6 gc_event::gc_event(gc_op op_, factor_vm *parent) :
   7         op(op_),
   8         cards_scanned(0),
   9         decks_scanned(0),
  10         code_blocks_scanned(0),
  11         start_time(nano_count()),
  12         card_scan_time(0),
  13         code_scan_time(0),
  14         data_sweep_time(0),
  15         code_sweep_time(0),
  16         compaction_time(0)
  17 {
  18         data_heap_before = parent->data_room();
  19         code_heap_before = parent->code_room();
  20         start_time = nano_count();
  21 }
  22
  23 void gc_event::started_card_scan()
  24 {
  25         temp_time = nano_count();
  26 }
  27
  28 void gc_event::ended_card_scan(cell cards_scanned_, cell decks_scanned_)
  29 {
  30         cards_scanned += cards_scanned_;
  31         decks_scanned += decks_scanned_;
  32         card_scan_time = (nano_count() - temp_time);
  33 }
  34
  35 void gc_event::started_code_scan()
  36 {
  37         temp_time = nano_count();
  38 }
  39
  40 void gc_event::ended_code_scan(cell code_blocks_scanned_)
  41 {
  42         code_blocks_scanned += code_blocks_scanned_;
  43         code_scan_time = (nano_count() - temp_time);
  44 }
  45
  46 void gc_event::started_data_sweep()
  47 {
  48         temp_time = nano_count();
  49 }
  50
  51 void gc_event::ended_data_sweep()
  52 {
  53         data_sweep_time = (nano_count() - temp_time);
  54 }
  55
  56 void gc_event::started_code_sweep()
  57 {
  58         temp_time = nano_count();
  59 }
  60
  61 void gc_event::ended_code_sweep()
  62 {
  63         code_sweep_time = (nano_count() - temp_time);
  64 }
  65
  66 void gc_event::started_compaction()
  67 {
  68         temp_time = nano_count();
  69 }
  70
  71 void gc_event::ended_compaction()
  72 {
  73         compaction_time = (nano_count() - temp_time);
  74 }
  75
  76 void gc_event::ended_gc(factor_vm *parent)
  77 {
  78         data_heap_after = parent->data_room();
  79         code_heap_after = parent->code_room();
  80         total_time = nano_count() - start_time;
  81 }
  82
  83 gc_state::gc_state(gc_op op_, factor_vm *parent) : op(op_), start_time(nano_count())
  84 {
  85         event = new gc_event(op,parent);
  86 }
  87
  88 gc_state::~gc_state()
  89 {
  90         delete event;
  91         event = NULL;
  92 }
  93
  94 void factor_vm::end_gc()
  95 {
  96         current_gc->event->ended_gc(this);
  97         if(gc_events) gc_events->push_back(*current_gc->event);
  98         delete current_gc->event;
  99         current_gc->event = NULL;
 100 }
 101
 102 void factor_vm::start_gc_again()
 103 {
 104         end_gc();
 105
 106         switch(current_gc->op)
 107         {
 108         case collect_nursery_op:
 109                 current_gc->op = collect_aging_op;
 110                 break;
 111         case collect_aging_op:
 112                 current_gc->op = collect_to_tenured_op;
 113                 break;
 114         case collect_to_tenured_op:
 115                 current_gc->op = collect_full_op;
 116                 break;
 117         case collect_full_op:
 118         case collect_compact_op:
 119                 current_gc->op = collect_growing_heap_op;
 120                 break;
 121         default:
 122                 critical_error("Bad GC op",current_gc->op);
 123                 break;
 124         }
 125
 126         current_gc->event = new gc_event(current_gc->op,this);
 127 }
 128
 129 void factor_vm::update_code_heap_for_minor_gc(std::set<code_block *> *remembered_set)
 130 {
 131         /* The youngest generation that any code block can now reference */
 132         std::set<code_block *>::const_iterator iter = remembered_set->begin();
 133         std::set<code_block *>::const_iterator end = remembered_set->end();
 134
 135         for(; iter != end; iter++) update_literal_references(*iter);
 136 }
 137
 138 void factor_vm::gc(gc_op op, cell requested_bytes, bool trace_contexts_p)
 139 {
 140         assert(!gc_off);
 141         assert(!current_gc);
 142
 143         save_stacks();
 144
 145         current_gc = new gc_state(op,this);
 146
 147         /* Keep trying to GC higher and higher generations until we don't run out
 148         of space */
 149         if(setjmp(current_gc->gc_unwind))
 150         {
 151                 /* We come back here if a generation is full */
 152                 start_gc_again();
 153         }
 154
 155         current_gc->event->op = current_gc->op;
 156
 157         switch(current_gc->op)
 158         {
 159         case collect_nursery_op:
 160                 collect_nursery();
 161                 break;
 162         case collect_aging_op:
 163                 collect_aging();
 164                 if(data->low_memory_p())
 165                 {
 166                         current_gc->op = collect_full_op;
 167                         current_gc->event->op = collect_full_op;
 168                         collect_full(trace_contexts_p);
 169                 }
 170                 break;
 171         case collect_to_tenured_op:
 172                 collect_to_tenured();
 173                 if(data->low_memory_p())
 174                 {
 175                         current_gc->op = collect_full_op;
 176                         current_gc->event->op = collect_full_op;
 177                         collect_full(trace_contexts_p);
 178                 }
 179                 break;
 180         case collect_full_op:
 181                 collect_full(trace_contexts_p);
 182                 break;
 183         case collect_compact_op:
 184                 collect_compact(trace_contexts_p);
 185                 break;
 186         case collect_growing_heap_op:
 187                 collect_growing_heap(requested_bytes,trace_contexts_p);
 188                 break;
 189         default:
 190                 critical_error("Bad GC op",current_gc->op);
 191                 break;
 192         }
 193
 194         end_gc();
 195
 196         delete current_gc;
 197         current_gc = NULL;
 198 }
 199
 200 void factor_vm::primitive_minor_gc()
 201 {
 202         gc(collect_nursery_op,
 203                 0, /* requested size */
 204                 true /* trace contexts? */);
 205 }
 206
 207 void factor_vm::primitive_full_gc()
 208 {
 209         gc(collect_full_op,
 210                 0, /* requested size */
 211                 true /* trace contexts? */);
 212 }
 213
 214 void factor_vm::primitive_compact_gc()
 215 {
 216         gc(collect_compact_op,
 217                 0, /* requested size */
 218                 true /* trace contexts? */);
 219 }
 220
 221 void factor_vm::inline_gc(cell *data_roots_base, cell data_roots_size)
 222 {
 223         data_roots.push_back(data_root_range(data_roots_base,data_roots_size));
 224         primitive_minor_gc();
 225         data_roots.pop_back();
 226 }
 227
 228 VM_C_API void inline_gc(cell *data_roots_base, cell data_roots_size, factor_vm *parent)
 229 {
 230         parent->inline_gc(data_roots_base,data_roots_size);
 231 }
 232
 233 /*
 234  * It is up to the caller to fill in the object's fields in a meaningful
 235  * fashion!
 236  */
 237 object *factor_vm::allot_large_object(cell type, cell size)
 238 {
 239         /* If tenured space does not have enough room, collect and compact */
 240         if(!data->tenured->can_allot_p(size))
 241         {
 242                 primitive_compact_gc();
 243
 244                 /* If it still won't fit, grow the heap */
 245                 if(!data->tenured->can_allot_p(size))
 246                 {
 247                         gc(collect_growing_heap_op,
 248                                 size, /* requested size */
 249                                 true /* trace contexts? */);
 250                 }
 251         }
 252
 253         object *obj = data->tenured->allot(size);
 254
 255         /* Allows initialization code to store old->new pointers
 256         without hitting the write barrier in the common case of
 257         a nursery allocation */
 258         write_barrier(obj,size);
 259
 260         obj->initialize(type);
 261         return obj;
 262 }
 263
 264 void factor_vm::primitive_enable_gc_events()
 265 {
 266         gc_events = new std::vector<gc_event>();
 267 }
 268
 269 void factor_vm::primitive_disable_gc_events()
 270 {
 271         if(gc_events)
 272         {
 273                 growable_array result(this);
 274
 275                 std::vector<gc_event> *gc_events = this->gc_events;
 276                 this->gc_events = NULL;
 277
 278                 std::vector<gc_event>::const_iterator iter = gc_events->begin();
 279                 std::vector<gc_event>::const_iterator end = gc_events->end();
 280
 281                 for(; iter != end; iter++)
 282                 {
 283                         gc_event event = *iter;
 284                         byte_array *obj = byte_array_from_value(&event);
 285                         result.add(tag<byte_array>(obj));
 286                 }
 287
 288                 result.trim();
 289                 dpush(result.elements.value());
 290
 291                 delete this->gc_events;
 292         }
 293         else
 294                 dpush(false_object);
 295 }
 296
 297 }