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::gc(gc_op op, cell requested_bytes, bool trace_contexts_p)
 130 {
 131         assert(!gc_off);
 132         assert(!current_gc);
 133
 134         save_stacks();
 135
 136         current_gc = new gc_state(op,this);
 137
 138         /* Keep trying to GC higher and higher generations until we don't run out
 139         of space */
 140         if(setjmp(current_gc->gc_unwind))
 141         {
 142                 /* We come back here if a generation is full */
 143                 start_gc_again();
 144         }
 145
 146         current_gc->event->op = current_gc->op;
 147
 148         switch(current_gc->op)
 149         {
 150         case collect_nursery_op:
 151                 collect_nursery();
 152                 break;
 153         case collect_aging_op:
 154                 collect_aging();
 155                 if(data->low_memory_p())
 156                 {
 157                         current_gc->op = collect_full_op;
 158                         current_gc->event->op = collect_full_op;
 159                         collect_full(trace_contexts_p);
 160                 }
 161                 break;
 162         case collect_to_tenured_op:
 163                 collect_to_tenured();
 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_full_op:
 172                 collect_full(trace_contexts_p);
 173                 break;
 174         case collect_compact_op:
 175                 collect_compact(trace_contexts_p);
 176                 break;
 177         case collect_growing_heap_op:
 178                 collect_growing_heap(requested_bytes,trace_contexts_p);
 179                 break;
 180         default:
 181                 critical_error("Bad GC op",current_gc->op);
 182                 break;
 183         }
 184
 185         end_gc();
 186
 187         delete current_gc;
 188         current_gc = NULL;
 189 }
 190
 191 void factor_vm::primitive_minor_gc()
 192 {
 193         gc(collect_nursery_op,
 194                 0, /* requested size */
 195                 true /* trace contexts? */);
 196 }
 197
 198 void factor_vm::primitive_full_gc()
 199 {
 200         gc(collect_full_op,
 201                 0, /* requested size */
 202                 true /* trace contexts? */);
 203 }
 204
 205 void factor_vm::primitive_compact_gc()
 206 {
 207         gc(collect_compact_op,
 208                 0, /* requested size */
 209                 true /* trace contexts? */);
 210 }
 211
 212 void factor_vm::inline_gc(cell *data_roots_base, cell data_roots_size)
 213 {
 214         data_roots.push_back(data_root_range(data_roots_base,data_roots_size));
 215         primitive_minor_gc();
 216         data_roots.pop_back();
 217 }
 218
 219 VM_C_API void inline_gc(cell *data_roots_base, cell data_roots_size, factor_vm *parent)
 220 {
 221         parent->inline_gc(data_roots_base,data_roots_size);
 222 }
 223
 224 /*
 225  * It is up to the caller to fill in the object's fields in a meaningful
 226  * fashion!
 227  */
 228 object *factor_vm::allot_large_object(cell type, cell size)
 229 {
 230         /* If tenured space does not have enough room, collect and compact */
 231         if(!data->tenured->can_allot_p(size))
 232         {
 233                 primitive_compact_gc();
 234
 235                 /* If it still won't fit, grow the heap */
 236                 if(!data->tenured->can_allot_p(size))
 237                 {
 238                         gc(collect_growing_heap_op,
 239                                 size, /* requested size */
 240                                 true /* trace contexts? */);
 241                 }
 242         }
 243
 244         object *obj = data->tenured->allot(size);
 245
 246         /* Allows initialization code to store old->new pointers
 247         without hitting the write barrier in the common case of
 248         a nursery allocation */
 249         write_barrier(obj,size);
 250
 251         obj->initialize(type);
 252         return obj;
 253 }
 254
 255 void factor_vm::primitive_enable_gc_events()
 256 {
 257         gc_events = new std::vector<gc_event>();
 258 }
 259
 260 void factor_vm::primitive_disable_gc_events()
 261 {
 262         if(gc_events)
 263         {
 264                 growable_array result(this);
 265
 266                 std::vector<gc_event> *gc_events = this->gc_events;
 267                 this->gc_events = NULL;
 268
 269                 std::vector<gc_event>::const_iterator iter = gc_events->begin();
 270                 std::vector<gc_event>::const_iterator end = gc_events->end();
 271
 272                 for(; iter != end; iter++)
 273                 {
 274                         gc_event event = *iter;
 275                         byte_array *obj = byte_array_from_value(&event);
 276                         result.add(tag<byte_array>(obj));
 277                 }
 278
 279                 result.trim();
 280                 dpush(result.elements.value());
 281
 282                 delete this->gc_events;
 283         }
 284         else
 285                 dpush(false_object);
 286 }
 287
 288 }