X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=ancient_c.c;h=58735d092eaa363ee84678c1a48acfa1783a529d;hb=refs%2Fheads%2Fmaster;hp=708a49654e625db804d35cf8ad2c1eb569b739f6;hpb=a34a08d6401b6b67c9d5d1260d816c8ea8b85558;p=ocaml-ancient.git diff --git a/ancient_c.c b/ancient_c.c index 708a496..58735d0 100644 --- a/ancient_c.c +++ b/ancient_c.c @@ -1,5 +1,4 @@ /* Mark objects as 'ancient' so they are taken out of the OCaml heap. - * $Id: ancient_c.c,v 1.5 2006-09-27 18:39:44 rich Exp $ */ #include @@ -13,10 +12,24 @@ #include "mmalloc/mmalloc.h" +// uintnat, intnat only appeared in Caml 3.09.x. +#if OCAML_VERSION_MAJOR == 3 && OCAML_VERSION_MINOR < 9 +typedef unsigned long uintnat; +typedef long intnat; +#endif + +/* We need the macro 'Is_in_young_or_heap' which tell us if a block + * address is within the OCaml minor or major heaps. This comes out + * of the guts of OCaml. + */ + +#if OCAML_VERSION_MAJOR == 3 && OCAML_VERSION_MINOR <= 10 +// Up to OCaml 3.10 there was a single contiguous page table. + // From byterun/misc.h: typedef char * addr; -// From byterun/minor_gc.c: +// From byterun/minor_gc.h: CAMLextern char *caml_young_start; CAMLextern char *caml_young_end; #define Is_young(val) \ @@ -32,7 +45,6 @@ typedef char page_table_entry; CAMLextern char *caml_heap_start; CAMLextern char *caml_heap_end; CAMLextern page_table_entry *caml_page_table; -extern asize_t caml_page_low, caml_page_high; #define In_heap 1 #define Not_in_heap 0 @@ -42,6 +54,47 @@ extern asize_t caml_page_low, caml_page_high; (addr)(p) >= (addr)caml_heap_start && (addr)(p) < (addr)caml_heap_end \ && caml_page_table [Page (p)]) +#define Is_in_heap_or_young(p) (Is_young (p) || Is_in_heap (p)) + +#else /* OCaml >= 3.11 */ + +// GC was rewritten in OCaml 3.11 so there is no longer a +// single contiguous page table. + +// From byterun/memory.h: +#define Not_in_heap 0 +#define In_heap 1 +#define In_young 2 +#define In_static_data 4 +#define In_code_area 8 + +#ifdef ARCH_SIXTYFOUR + +/* 64 bits: Represent page table as a sparse hash table */ +int caml_page_table_lookup(void * addr); +#define Classify_addr(a) (caml_page_table_lookup((void *)(a))) + +#else + +/* 32 bits: Represent page table as a 2-level array */ +#define Pagetable2_log 11 +#define Pagetable2_size (1 << Pagetable2_log) +#define Pagetable1_log (Page_log + Pagetable2_log) +#define Pagetable1_size (1 << (32 - Pagetable1_log)) +CAMLextern unsigned char * caml_page_table[Pagetable1_size]; + +#define Pagetable_index1(a) (((uintnat)(a)) >> Pagetable1_log) +#define Pagetable_index2(a) \ + ((((uintnat)(a)) >> Page_log) & (Pagetable2_size - 1)) +#define Classify_addr(a) \ + caml_page_table[Pagetable_index1(a)][Pagetable_index2(a)] + +#endif + +#define Is_in_heap_or_young(a) (Classify_addr(a) & (In_heap | In_young)) + +#endif /* OCaml >= 3.11 */ + // Area is an expandable buffer, allocated on the C heap. typedef struct area { void *ptr; // Start of area. @@ -80,13 +133,15 @@ area_init_custom (area *a, static inline int area_append (area *a, const void *obj, size_t size) { + void *ptr; while (a->n + size > a->size) { if (a->size == 0) a->size = 256; else a->size <<= 1; - a->ptr = + ptr = a->realloc ? a->realloc (a->data, a->ptr, a->size) : realloc (a->ptr, a->size); - if (a->ptr == 0) return -1; // Out of memory. + if (ptr == 0) return -1; // Out of memory. + a->ptr = ptr; } memcpy (a->ptr + a->n, obj, size); a->n += size; @@ -144,20 +199,24 @@ static header_t visited = (unsigned long) -1; // Temporary solution: 'ulimit -s unlimited'. This function should // be replaced with something iterative. static size_t -mark (value obj, area *ptr, area *restore, area *fixups) +_mark (value obj, area *ptr, area *restore, area *fixups) { - char *header = Hp_val (obj); - assert (Wosize_hp (header) > 0); // Always true? (XXX) - // XXX This assertion might fail if someone tries to mark an object // which is already ancient. - assert (Is_young (obj) || Is_in_heap (obj)); + assert (Is_in_heap_or_young (obj)); + + char *header = Hp_val (obj); // If we've already visited this object, just return its offset // in the out-of-heap memory. if (memcmp (header, &visited, sizeof visited) == 0) return (Long_val (Field (obj, 0))); + // XXX Actually this fails if you try to persist a zero-length + // array. Needs to be fixed, but it breaks some rather important + // functions below. + assert (Wosize_hp (header) > 0); + // Offset where we will store this object in the out-of-heap memory. size_t offset = ptr->n; @@ -176,8 +235,8 @@ mark (value obj, area *ptr, area *restore, area *fixups) value field = Field (obj, i); if (Is_block (field) && - (Is_young (field) || Is_in_heap (field))) { - size_t field_offset = mark (field, ptr, restore, fixups); + Is_in_heap_or_young (field)) { + size_t field_offset = _mark (field, ptr, restore, fixups); if (field_offset == -1) return -1; // Propagate out of memory errors. // Since the recursive call to mark above can reallocate the @@ -187,7 +246,7 @@ mark (value obj, area *ptr, area *restore, area *fixups) // Don't store absolute pointers yet because realloc will // move the memory around. Store a fake pointer instead. - // We'll fix up these fake pointers afterwards. + // We'll fix up these fake pointers afterwards in do_fixups. Field (obj_copy, i) = field_offset + sizeof (header_t); size_t fixup = (void *)&Field(obj_copy, i) - ptr->ptr; @@ -207,7 +266,8 @@ mark (value obj, area *ptr, area *restore, area *fixups) // what was in that field before. // (3) We can overwrite the header with all 1's to indicate that // we've visited (but see notes on 'static header_t visited' above). - // (4) All objects in OCaml are at least one word long (we hope!). + // (4) All objects in OCaml are at least one word long (XXX - actually + // this is not true). struct restore_item restore_item; restore_item.header = header; restore_item.field_zero = Field (obj, 0); @@ -260,10 +320,11 @@ do_fixups (area *ptr, area *fixups) } static void * -do_mark (value obj, - void *(*realloc)(void *data, void *ptr, size_t size), - void (*free)(void *data, void *ptr), - void *data) +mark (value obj, + void *(*realloc)(void *data, void *ptr, size_t size), + void (*free)(void *data, void *ptr), + void *data, + size_t *r_size) { area ptr; // This will be the out of heap area. area_init_custom (&ptr, realloc, free, data); @@ -272,7 +333,7 @@ do_mark (value obj, area fixups; // List of fake pointers to be fixed up. area_init (&fixups); - if (mark (obj, &ptr, &restore, &fixups) == -1) { + if (_mark (obj, &ptr, &restore, &fixups) == -1) { // Ran out of memory. Recover and throw an exception. area_free (&fixups); do_restore (&ptr, &restore); @@ -291,6 +352,7 @@ do_mark (value obj, do_fixups (&ptr, &fixups); area_free (&fixups); + if (r_size) *r_size = ptr.size; return ptr.ptr; } @@ -307,18 +369,27 @@ my_free (void *data __attribute__((unused)), void *ptr) } CAMLprim value -ancient_mark (value obj) +ancient_mark_info (value obj) { CAMLparam1 (obj); - CAMLlocal1 (proxy); + CAMLlocal3 (proxy, info, rv); - void *ptr = do_mark (obj, my_realloc, my_free, 0); + size_t size; + void *ptr = mark (obj, my_realloc, my_free, 0, &size); - // Return the proxy. + // Make the proxy. proxy = caml_alloc (1, Abstract_tag); Field (proxy, 0) = (value) ptr; - CAMLreturn (proxy); + // Make the info struct. + info = caml_alloc (1, 0); + Field (info, 0) = Val_long (size); + + rv = caml_alloc (2, 0); + Field (rv, 0) = proxy; + Field (rv, 1) = info; + + CAMLreturn (rv); } CAMLprim value @@ -344,7 +415,7 @@ ancient_delete (value obj) if (Is_long (v)) caml_invalid_argument ("deleted"); // Otherwise v is a pointer to the out of heap malloc'd object. - assert (!Is_young (v) && !Is_in_heap (v)); + assert (!Is_in_heap_or_young (v)); free ((void *) v); // Replace the proxy (a pointer) with an int 0 so we know it's @@ -355,13 +426,37 @@ ancient_delete (value obj) } CAMLprim value -ancient_attach (value fdv) +ancient_is_ancient (value obj) +{ + CAMLparam1 (obj); + CAMLlocal1 (v); + + v = Is_in_heap_or_young (obj) ? Val_false : Val_true; + + CAMLreturn (v); +} + +CAMLprim value +ancient_address_of (value obj) { - CAMLparam1 (fdv); + CAMLparam1 (obj); + CAMLlocal1 (v); + + if (Is_block (obj)) v = caml_copy_nativeint ((intnat) obj); + else v = caml_copy_nativeint (0); + + CAMLreturn (v); +} + +CAMLprim value +ancient_attach (value fdv, value baseaddrv) +{ + CAMLparam2 (fdv, baseaddrv); CAMLlocal1 (mdv); int fd = Int_val (fdv); - void *md = mmalloc_attach (fd, 0); + void *baseaddr = (void *) Nativeint_val (baseaddrv); + void *md = mmalloc_attach (fd, baseaddr); if (md == 0) { perror ("mmalloc_attach"); caml_failwith ("mmalloc_attach"); @@ -388,29 +483,67 @@ ancient_detach (value mdv) CAMLreturn (Val_unit); } +struct keytable { + void **keys; + int allocated; +}; + CAMLprim value -ancient_share (value mdv, value keyv, value obj) +ancient_share_info (value mdv, value keyv, value obj) { CAMLparam3 (mdv, keyv, obj); - CAMLlocal1 (proxy); + CAMLlocal3 (proxy, info, rv); void *md = (void *) Field (mdv, 0); int key = Int_val (keyv); + // Get the key table. + struct keytable *keytable = mmalloc_getkey (md, 0); + if (keytable == 0) { + keytable = mmalloc (md, sizeof (struct keytable)); + if (keytable == 0) caml_failwith ("out of memory"); + keytable->keys = 0; + keytable->allocated = 0; + mmalloc_setkey (md, 0, keytable); + } + // Existing key exists? Free it. - void *old_obj = mmalloc_getkey (md, key); - if (old_obj != 0) mfree (md, old_obj); - mmalloc_setkey (md, key, 0); + if (key < keytable->allocated && keytable->keys[key] != 0) { + mfree (md, keytable->keys[key]); + keytable->keys[key] = 0; + } + + // Keytable large enough? If not, realloc it. + if (key >= keytable->allocated) { + int allocated = keytable->allocated == 0 ? 32 : keytable->allocated * 2; + void **keys = mrealloc (md, keytable->keys, allocated * sizeof (void *)); + if (keys == 0) caml_failwith ("out of memory"); + int i; + for (i = keytable->allocated; i < allocated; ++i) keys[i] = 0; + keytable->keys = keys; + keytable->allocated = allocated; + } - void *ptr = do_mark (obj, mrealloc, mfree, md); + // Do the mark. + size_t size; + void *ptr = mark (obj, mrealloc, mfree, md, &size); - mmalloc_setkey (md, key, ptr); + // Add the key to the keytable. + keytable->keys[key] = ptr; - // Return the proxy. + // Make the proxy. proxy = caml_alloc (1, Abstract_tag); Field (proxy, 0) = (value) ptr; - CAMLreturn (proxy); + // Make the info struct. + info = caml_alloc (1, 0); + Field (info, 0) = Val_long (size); + + rv = caml_alloc (2, 0); + Field (rv, 0) = proxy; + Field (rv, 1) = info; + + CAMLreturn (rv); } CAMLprim value @@ -422,8 +555,11 @@ ancient_get (value mdv, value keyv) void *md = (void *) Field (mdv, 0); int key = Int_val (keyv); - void *ptr = mmalloc_getkey (md, key); - if (!ptr) caml_raise_not_found (); + // Key exists? + struct keytable *keytable = mmalloc_getkey (md, 0); + if (keytable == 0 || key >= keytable->allocated || keytable->keys[key] == 0) + caml_raise_not_found (); + void *ptr = keytable->keys[key]; // Return the proxy. proxy = caml_alloc (1, Abstract_tag);