From e291c1776cff0446435b392285b7ec6abe5373bd Mon Sep 17 00:00:00 2001 From: Rickard Green Date: Fri, 25 Apr 2014 21:37:17 +0200 Subject: Make binary BIFs converting to lists yield on large input - erlang:binary_to_list/1 - erlang:binary_to_list/3 - erlang:bitstring_to_list/1 --- erts/emulator/beam/binary.c | 149 ++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 144 insertions(+), 5 deletions(-) (limited to 'erts/emulator/beam/binary.c') diff --git a/erts/emulator/beam/binary.c b/erts/emulator/beam/binary.c index c7926f18af..4fd47210a2 100644 --- a/erts/emulator/beam/binary.c +++ b/erts/emulator/beam/binary.c @@ -38,6 +38,11 @@ static int list_to_bitstr_buf(Eterm obj, char* buf); #endif static int bitstr_list_len(Eterm obj, Uint* num_bytes); +static Export binary_to_list_continue_export; + +static BIF_RETTYPE binary_to_list_continue(BIF_ALIST_1); + + void erts_init_binary(void) { @@ -49,6 +54,11 @@ erts_init_binary(void) "Internal error: Address of orig_bytes[0] of a Binary" " is *not* 8-byte aligned\n"); } + + erts_init_trap_export(&binary_to_list_continue_export, + am_erts_internal, am_binary_to_list_continue, 1, + &binary_to_list_continue); + } /* @@ -333,6 +343,132 @@ BIF_RETTYPE integer_to_binary_1(BIF_ALIST_1) BIF_RET(res); } +#define ERTS_B2L_BYTES_PER_REDUCTION 256 + +typedef struct { + Eterm res; + Eterm *hp; +#ifdef DEBUG + Eterm *hp_end; +#endif + byte *bytes; + Uint size; + Uint bitoffs; +} ErtsB2LState; + +static void b2l_state_destructor(Binary *mbp) +{ + ASSERT(ERTS_MAGIC_BIN_DESTRUCTOR(mbp) == b2l_state_destructor); +} + +static BIF_RETTYPE +binary_to_list_chunk(Process *c_p, + Eterm mb_eterm, + ErtsB2LState* sp, + int reds_left, + int gc_disabled) +{ + BIF_RETTYPE ret; + int bump_reds; + Uint size; + byte *bytes; + + size = (reds_left + 1)*ERTS_B2L_BYTES_PER_REDUCTION; + if (size > sp->size) + size = sp->size; + bytes = sp->bytes + (sp->size - size); + + bump_reds = (size - 1)/ERTS_B2L_BYTES_PER_REDUCTION + 1; + BUMP_REDS(c_p, bump_reds); + + ASSERT(is_list(sp->res) || is_nil(sp->res)); + + sp->res = erts_bin_bytes_to_list(sp->res, + sp->hp, + bytes, + size, + sp->bitoffs); + sp->size -= size; + sp->hp += 2*size; + + if (sp->size > 0) { + + if (!gc_disabled) + erts_set_gc_state(c_p, 0); + + ASSERT(c_p->flags & F_DISABLE_GC); + ASSERT(is_value(mb_eterm)); + ERTS_BIF_PREP_TRAP1(ret, + &binary_to_list_continue_export, + c_p, + mb_eterm); + } + else { + + ASSERT(sp->hp == sp->hp_end); + ASSERT(sp->size == 0); + + if (!gc_disabled || !erts_set_gc_state(c_p, 1)) + ERTS_BIF_PREP_RET(ret, sp->res); + else + ERTS_BIF_PREP_YIELD_RETURN(ret, c_p, sp->res); + ASSERT(!(c_p->flags & F_DISABLE_GC)); + } + + return ret; +} + +static ERTS_INLINE BIF_RETTYPE +binary_to_list(Process *c_p, Eterm *hp, Eterm tail, byte *bytes, Uint size, Uint bitoffs) +{ + int reds_left = ERTS_BIF_REDS_LEFT(c_p); + if (size < reds_left*ERTS_B2L_BYTES_PER_REDUCTION) { + Eterm res; + BIF_RETTYPE ret; + int bump_reds = (size - 1)/ERTS_B2L_BYTES_PER_REDUCTION + 1; + BUMP_REDS(c_p, bump_reds); + res = erts_bin_bytes_to_list(tail, hp, bytes, size, bitoffs); + ERTS_BIF_PREP_RET(ret, res); + return ret; + } + else { + Binary *mbp = erts_create_magic_binary(sizeof(ErtsB2LState), + b2l_state_destructor); + ErtsB2LState *sp = ERTS_MAGIC_BIN_DATA(mbp); + Eterm mb; + + sp->res = tail; + sp->hp = hp; +#ifdef DEBUG + sp->hp_end = sp->hp + 2*size; +#endif + sp->bytes = bytes; + sp->size = size; + sp->bitoffs = bitoffs; + + hp = HAlloc(c_p, PROC_BIN_SIZE); + mb = erts_mk_magic_binary_term(&hp, &MSO(c_p), mbp); + return binary_to_list_chunk(c_p, mb, sp, reds_left, 0); + } +} + +static BIF_RETTYPE binary_to_list_continue(BIF_ALIST_1) +{ + Binary *mbp = ((ProcBin *) binary_val(BIF_ARG_1))->val; + + ASSERT(ERTS_MAGIC_BIN_DESTRUCTOR(mbp) == b2l_state_destructor); + + ASSERT(BIF_P->flags & F_DISABLE_GC); + + return binary_to_list_chunk(BIF_P, + BIF_ARG_1, + (ErtsB2LState*) ERTS_MAGIC_BIN_DATA(mbp), + ERTS_BIF_REDS_LEFT(BIF_P), + 1); +} + +HIPE_WRAPPER_BIF_DISABLE_GC(binary_to_list, 1) + BIF_RETTYPE binary_to_list_1(BIF_ALIST_1) { Eterm real_bin; @@ -354,14 +490,15 @@ BIF_RETTYPE binary_to_list_1(BIF_ALIST_1) } else { Eterm* hp = HAlloc(BIF_P, 2 * size); byte* bytes = binary_bytes(real_bin)+offset; - - BIF_RET(erts_bin_bytes_to_list(NIL, hp, bytes, size, bitoffs)); + return binary_to_list(BIF_P, hp, NIL, bytes, size, bitoffs); } error: BIF_ERROR(BIF_P, BADARG); } +HIPE_WRAPPER_BIF_DISABLE_GC(binary_to_list, 3) + BIF_RETTYPE binary_to_list_3(BIF_ALIST_3) { byte* bytes; @@ -387,12 +524,13 @@ BIF_RETTYPE binary_to_list_3(BIF_ALIST_3) } i = stop-start+1; hp = HAlloc(BIF_P, 2*i); - BIF_RET(erts_bin_bytes_to_list(NIL, hp, bytes+start-1, i, bitoffs)); - + return binary_to_list(BIF_P, hp, NIL, bytes+start-1, i, bitoffs); error: BIF_ERROR(BIF_P, BADARG); } +HIPE_WRAPPER_BIF_DISABLE_GC(bitstring_to_list, 1) + BIF_RETTYPE bitstring_to_list_1(BIF_ALIST_1) { Eterm real_bin; @@ -431,7 +569,8 @@ BIF_RETTYPE bitstring_to_list_1(BIF_ALIST_1) previous = CONS(hp, make_binary(last), previous); hp += 2; } - BIF_RET(erts_bin_bytes_to_list(previous, hp, bytes, size, bitoffs)); + + return binary_to_list(BIF_P, hp, previous, bytes, size, bitoffs); } -- cgit v1.2.3