ocaml/byterun/gc_ctrl.c

374 lines
11 KiB
C

/***********************************************************************/
/* */
/* Objective Caml */
/* */
/* Damien Doligez, projet Para, INRIA Rocquencourt */
/* */
/* Copyright 1996 Institut National de Recherche en Informatique et */
/* en Automatique. Distributed only by permission. */
/* */
/***********************************************************************/
/* $Id$ */
#include "alloc.h"
#include "compact.h"
#include "gc.h"
#include "gc_ctrl.h"
#include "major_gc.h"
#include "minor_gc.h"
#include "misc.h"
#include "mlvalues.h"
#include "stacks.h"
#ifndef NATIVE_CODE
extern unsigned long max_stack_size; /* defined in stacks.c */
#endif
long stat_minor_words = 0,
stat_promoted_words = 0,
stat_major_words = 0,
stat_minor_collections = 0,
stat_major_collections = 0,
stat_heap_size = 0, /* bytes */
stat_compactions = 0;
extern asize_t major_heap_increment; /* bytes; see major_gc.c */
extern unsigned long percent_free; /* see major_gc.c */
extern unsigned long percent_max; /* see compact.c */
#define Next(hp) ((hp) + Bhsize_hp (hp))
#ifdef DEBUG
/* Check that [v]'s header looks good. [v] must be a block in the heap. */
static void check_head (value v)
{
Assert (Is_block (v) && Is_in_heap (v));
Assert (Wosize_val (v) != 0);
Assert (Color_hd (Hd_val (v)) != Blue);
Assert (Is_in_heap (v));
if (Tag_val (v) == Infix_tag){
int offset = Wsize_bsize (Infix_offset_val (v));
value trueval = Val_op (&Field (v, -offset));
Assert (Tag_val (trueval) == Closure_tag);
Assert (Wosize_val (trueval) > offset);
Assert (Is_in_heap (&Field (trueval, Wosize_val (trueval) - 1)));
}else{
Assert (Is_in_heap (&Field (v, Wosize_val (v) - 1)));
}
if (Tag_val (v) == Double_tag){
Assert (Wosize_val (v) == Double_wosize);
}else if (Tag_val (v) == Double_array_tag){
Assert (Wosize_val (v) % Double_wosize == 0);
}
}
static void check_block (char *hp)
{
mlsize_t nfields = Wosize_hp (hp);
mlsize_t i;
value v = Val_hp (hp);
value f;
mlsize_t lastbyte;
check_head (v);
switch (Tag_hp (hp)){
case Abstract_tag: break;
case String_tag:
/* not true when check_urgent_gc is called by alloc or alloc_string:
lastbyte = Bosize_val (v) - 1;
i = Byte (v, lastbyte);
Assert (i >= 0 && i < sizeof (value));
Assert (Byte (v, lastbyte - i) == 0);
*/
break;
case Double_tag:
Assert (Wosize_val (v) == Double_wosize);
break;
case Double_array_tag:
Assert (Wosize_val (v) % Double_wosize == 0);
break;
case Final_tag:
Assert (!Is_in_heap (Final_fun (v)));
break;
case Infix_tag:
Assert (0);
break;
default:
Assert (Tag_hp (hp) < No_scan_tag);
for (i = 0; i < Wosize_hp (hp); i++){
f = Field (v, i);
if (Is_block (f) && Is_in_heap (f)) check_head (f);
}
}
}
#endif /* DEBUG */
/* Check the heap structure (if compiled in debug mode) and
gather statistics; return the stats if [returnstats] is true,
otherwise return [Val_unit].
*/
static value heap_stats (int returnstats)
{
long live_words = 0, live_blocks = 0,
free_words = 0, free_blocks = 0, largest_free = 0,
fragments = 0, heap_chunks = 0;
char *chunk = heap_start, *chunk_end;
char *cur_hp, *prev_hp;
header_t cur_hd;
#ifdef DEBUG
gc_message (0xFFFF, "### O'Caml runtime: heap check ###\n", 0);
#endif
while (chunk != NULL){
++ heap_chunks;
chunk_end = chunk + Chunk_size (chunk);
prev_hp = NULL;
cur_hp = chunk;
while (cur_hp < chunk_end){
cur_hd = Hd_hp (cur_hp);
Assert (Next (cur_hp) <= chunk_end);
switch (Color_hd (cur_hd)){
case White:
if (Wosize_hd (cur_hd) == 0){
++fragments;
Assert (prev_hp == NULL
|| (Color_hp (prev_hp) != Blue && Wosize_hp (prev_hp) > 0)
|| cur_hp == gc_sweep_hp);
Assert (Next (cur_hp) == chunk_end
|| (Color_hp (Next (cur_hp)) != Blue
&& Wosize_hp (Next (cur_hp)) > 0)
|| Next (cur_hp) == gc_sweep_hp);
}else{
if (gc_phase == Phase_mark || gc_phase == Phase_idle){
++ live_blocks;
live_words += Whsize_hd (cur_hd);
#ifdef DEBUG
check_block (cur_hp);
#endif
}
}
break;
case Gray: case Black:
Assert (Wosize_hd (cur_hd) > 0);
++ live_blocks;
live_words += Whsize_hd (cur_hd);
#ifdef DEBUG
check_block (cur_hp);
#endif
break;
case Blue:
Assert (Wosize_hd (cur_hd) > 0);
++ free_blocks;
free_words += Whsize_hd (cur_hd);
if (Whsize_hd (cur_hd) > largest_free){
largest_free = Whsize_hd (cur_hd);
}
Assert (prev_hp == NULL
|| (Color_hp (prev_hp) != Blue && Wosize_hp (prev_hp) > 0)
|| cur_hp == gc_sweep_hp);
Assert (Next (cur_hp) == chunk_end
|| (Color_hp (Next (cur_hp)) != Blue
&& Wosize_hp (Next (cur_hp)) > 0)
|| Next (cur_hp) == gc_sweep_hp);
break;
}
prev_hp = cur_hp;
cur_hp = Next (cur_hp);
} Assert (cur_hp == chunk_end);
chunk = Chunk_next (chunk);
}
Assert (live_words + free_words + fragments == Wsize_bsize (stat_heap_size));
if (returnstats){
value res = alloc_small (14, 0);
Field (res, 0) = Val_long (stat_minor_words
+ Wsize_bsize (young_end - young_ptr));
Field (res, 1) = Val_long (stat_promoted_words);
Field (res, 2) = Val_long (stat_major_words + allocated_words);
Field (res, 3) = Val_long (stat_minor_collections);
Field (res, 4) = Val_long (stat_major_collections);
Field (res, 5) = Val_long (Wsize_bsize (stat_heap_size));
Field (res, 6) = Val_long (heap_chunks);
Field (res, 7) = Val_long (live_words);
Field (res, 8) = Val_long (live_blocks);
Field (res, 9) = Val_long (free_words);
Field (res, 10) = Val_long (free_blocks);
Field (res, 11) = Val_long (largest_free);
Field (res, 12) = Val_long (fragments);
Field (res, 13) = Val_long (stat_compactions);
return res;
}else{
return Val_unit;
}
}
#ifdef DEBUG
void heap_check (void)
{
heap_stats (0);
}
#endif
value gc_stat(value v) /* ML */
{
Assert (v == Val_unit);
return heap_stats (1);
}
value gc_get(value v) /* ML */
{
value res;
Assert (v == Val_unit);
res = alloc_small (6, 0);
Field (res, 0) = Wsize_bsize (Val_long (minor_heap_size)); /* s */
Field (res, 1) = Wsize_bsize (Val_long (major_heap_increment)); /* i */
Field (res, 2) = Val_long (percent_free); /* o */
Field (res, 3) = Val_long (verb_gc); /* v */
Field (res, 4) = Val_long (percent_max); /* O */
#ifndef NATIVE_CODE
Field (res, 5) = Val_long (max_stack_size); /* l */
#else
Field (res, 5) = 0;
#endif
return res;
}
#define Max(x,y) ((x) < (y) ? (y) : (x))
static unsigned long norm_pfree (long unsigned int p)
{
return Max (p, 1);
}
static unsigned long norm_pmax (long unsigned int p)
{
return p;
}
static long norm_heapincr (long unsigned int i)
{
#define Psv (Wsize_bsize (Page_size))
i = ((i + Psv - 1) / Psv) * Psv;
if (i < Heap_chunk_min) i = Heap_chunk_min;
if (i > Heap_chunk_max) i = Heap_chunk_max;
return i;
}
static long norm_minsize (long int s)
{
if (s < Minor_heap_min) s = Minor_heap_min;
if (s > Minor_heap_max) s = Minor_heap_max;
return s;
}
value gc_set(value v) /* ML */
{
unsigned long newpf, newpm;
asize_t newheapincr;
asize_t newminsize;
verb_gc = Long_val (Field (v, 3));
#ifndef NATIVE_CODE
change_max_stack_size (Long_val (Field (v, 5)));
#endif
newpf = norm_pfree (Long_val (Field (v, 2)));
if (newpf != percent_free){
percent_free = newpf;
gc_message (0x20, "New space overhead: %d%%\n", percent_free);
}
newpm = norm_pmax (Long_val (Field (v, 4)));
if (newpm != percent_max){
percent_max = newpm;
gc_message (0x20, "New max overhead: %d%%\n", percent_max);
}
newheapincr = norm_heapincr (Bsize_wsize (Long_val (Field (v, 1))));
if (newheapincr != major_heap_increment){
major_heap_increment = newheapincr;
gc_message (0x20, "New heap increment size: %luk bytes\n",
major_heap_increment/1024);
}
/* Minor heap size comes last because it will trigger a minor collection
(thus invalidating [v]) and it can raise [Out_of_memory]. */
newminsize = norm_minsize (Bsize_wsize (Long_val (Field (v, 0))));
if (newminsize != minor_heap_size){
gc_message (0x20, "New minor heap size: %luk bytes\n", newminsize/1024);
set_minor_heap_size (newminsize);
}
return Val_unit;
}
value gc_minor(value v) /* ML */
{ Assert (v == Val_unit);
minor_collection ();
return Val_unit;
}
value gc_major(value v) /* ML */
{ Assert (v == Val_unit);
minor_collection ();
finish_major_cycle ();
return Val_unit;
}
value gc_full_major(value v) /* ML */
{ Assert (v == Val_unit);
minor_collection ();
finish_major_cycle ();
finish_major_cycle ();
return Val_unit;
}
value gc_compaction(value v) /* ML */
{ Assert (v == Val_unit);
minor_collection ();
finish_major_cycle ();
finish_major_cycle ();
compact_heap ();
return Val_unit;
}
void init_gc (unsigned long minor_size, unsigned long major_size,
unsigned long major_incr, unsigned long percent_fr,
unsigned long percent_m, unsigned long verb)
{
unsigned long major_heap_size = Bsize_wsize (norm_heapincr (major_size));
#ifdef DEBUG
gc_message (0xFFFF, "### O'Caml runtime: debug mode "
#ifdef CPU_TYPE_STRING
"(" CPU_TYPE_STRING ") "
#endif
"###\n", 0);
#endif /* DEBUG */
verb_gc = verb;
set_minor_heap_size (Bsize_wsize (norm_minsize (minor_size)));
major_heap_increment = Bsize_wsize (norm_heapincr (major_incr));
percent_free = norm_pfree (percent_fr);
percent_max = norm_pmax (percent_m);
init_major_heap (major_heap_size);
gc_message (0x20, "Initial minor heap size: %luk bytes\n",
minor_heap_size / 1024);
gc_message (0x20, "Initial major heap size: %luk bytes\n",
major_heap_size / 1024);
gc_message (0x20, "Initial space overhead: %lu%%\n", percent_free);
gc_message (0x20, "Initial max overhead: %lu%%\n", percent_max);
gc_message (0x20, "Initial heap increment: %luk bytes\n",
major_heap_increment / 1024);
}