From b49efb826e191a0ef18da7ebdb3dd9e56fe654da Mon Sep 17 00:00:00 2001 From: Sverker Eriksson Date: Fri, 10 Jan 2014 15:41:48 +0100 Subject: erts: Simplify term_to_binary by removing saved ESTACK from root set We disabled GC (in 522a29666088d5) during trapping and don't need to include the saved ESTACK as part of root set. --- erts/emulator/beam/external.c | 219 ++++++++++++++++++++---------------------- 1 file changed, 104 insertions(+), 115 deletions(-) (limited to 'erts/emulator/beam/external.c') diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c index 2cb44a5b64..50831e848e 100644 --- a/erts/emulator/beam/external.c +++ b/erts/emulator/beam/external.c @@ -1,7 +1,7 @@ /* * %CopyrightBegin% * - * Copyright Ericsson AB 1996-2013. All Rights Reserved. + * Copyright Ericsson AB 1996-2014. All Rights Reserved. * * The contents of this file are subject to the Erlang Public License, * Version 1.1, (the "License"); you may not use this file except in @@ -87,7 +87,8 @@ static Export term_to_binary_trap_export; static byte* enc_term(ErtsAtomCacheMap *, Eterm, byte*, Uint32, struct erl_off_heap_header** off_heap); -static int enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags, +struct TTBEncodeContext_; +static int enc_term_int(struct TTBEncodeContext_*,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags, struct erl_off_heap_header** off_heap, Sint *reds, byte **res); static Uint is_external_string(Eterm obj, int* p_is_string); static byte* enc_atom(ErtsAtomCacheMap *, Eterm, byte*, Uint32); @@ -103,7 +104,8 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla Binary *context_b); static Uint encode_size_struct2(ErtsAtomCacheMap *, Eterm, unsigned); -static int encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj, +struct TTBSizeContext_; +static int encode_size_struct_int(struct TTBSizeContext_*, ErtsAtomCacheMap *acmp, Eterm obj, unsigned dflags, Sint *reds, Uint *res); static Export binary_to_term_trap_export; @@ -1086,7 +1088,6 @@ BIF_RETTYPE term_to_binary_2(BIF_ALIST_2) int level = 0; Uint flags = TERM_TO_BINARY_DFLAGS; Eterm res; - Binary *bin = NULL; while (is_list(Flags)) { Eterm arg = CAR(list_val(Flags)); @@ -1123,7 +1124,7 @@ BIF_RETTYPE term_to_binary_2(BIF_ALIST_2) goto error; } - res = erts_term_to_binary_int(p, Term, level, flags, bin); + res = erts_term_to_binary_int(p, Term, level, flags, NULL); if (is_tuple(res)) { erts_set_gc_state(p, 0); BIF_TRAP1(&term_to_binary_trap_export,BIF_P,res); @@ -1726,14 +1727,22 @@ erts_term_to_binary(Process* p, Eterm Term, int level, Uint flags) { typedef enum { TTBSize, TTBEncode, TTBCompress } TTBState; -typedef struct { +typedef struct TTBSizeContext_ { Uint flags; int level; + Uint result; + Eterm obj; + UWord* stack; + Uint stack_sz; } TTBSizeContext; -typedef struct { +typedef struct TTBEncodeContext_ { Uint flags; int level; + byte* ep; + Eterm obj; + UWord* stack; + Uint stack_sz; Binary *result_bin; } TTBEncodeContext; @@ -1763,8 +1772,16 @@ static void ttb_context_destructor(Binary *context_bin) context->alive = 0; switch (context->state) { case TTBSize: + if (context->s.sc.stack) { + erts_free(ERTS_ALC_T_SAVED_ESTACK, context->s.sc.stack); + context->s.sc.stack = NULL; + } break; case TTBEncode: + if (context->s.ec.stack) { + erts_free(ERTS_ALC_T_SAVED_ESTACK, context->s.ec.stack); + context->s.ec.stack = NULL; + } if (context->s.ec.result_bin != NULL) { /* Set to NULL if ever made alive! */ ASSERT(erts_refc_read(&(context->s.ec.result_bin->refc),0) == 0); erts_bin_free(context->s.ec.result_bin); @@ -1829,6 +1846,7 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla /* Setup enough to get started */ context->state = TTBSize; context->alive = 1; + context->s.sc.stack = NULL; context->s.sc.flags = flags; context->s.sc.level = level; } else { @@ -1844,7 +1862,8 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla int level; Uint flags; /* Try for fast path */ - if (encode_size_struct_int(p, NULL, Term, context->s.sc.flags, &reds, &size) < 0) { + if (encode_size_struct_int(&context->s.sc, NULL, Term, + context->s.sc.flags, &reds, &size) < 0) { EXPORT_CONTEXT(); /* Same state */ RETURN_STATE(); @@ -1870,6 +1889,7 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla context->state = TTBEncode; context->s.ec.flags = flags; context->s.ec.level = level; + context->s.ec.stack = NULL; context->s.ec.result_bin = result_bin; break; } @@ -1881,7 +1901,7 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla Binary *result_bin; flags = context->s.ec.flags; - if (enc_term_int(p,NULL,Term, bytes+1, flags, NULL, &reds, &endp) < 0) { + if (enc_term_int(&context->s.ec, NULL,Term, bytes+1, flags, NULL, &reds, &endp) < 0) { EXPORT_CONTEXT(); RETURN_STATE(); } @@ -2289,27 +2309,6 @@ dec_pid(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Ete #define ENC_PATCH_FUN_SIZE ((Eterm) 2) #define ENC_LAST_ARRAY_ELEMENT ((Eterm) 3) -/* Free extra rootset (used when trapping) */ -static void cleanup_ttb_extra_root(ErlExtraRootSet *rs) -{ - if (rs->objv != NULL) { - erts_free(ERTS_ALC_T_EXTRA_ROOT, rs->objv); - } - erts_free(ERTS_ALC_T_EXTRA_ROOT, rs); -} - -/* Same as above, but we have an extra "stack" beyond GC reach, i.e. an array of two extra roots */ -static void cleanup_ttb_extra_root_2(ErlExtraRootSet *rs) -{ - if (rs->objv != NULL) { - erts_free(ERTS_ALC_T_EXTRA_ROOT, rs->objv); - } - if (rs[1].objv != NULL) { - erts_free(ERTS_ALC_T_EXTRA_ROOT, rs[1].objv); - } - - erts_free(ERTS_ALC_T_EXTRA_ROOT, rs); -} static byte* enc_term(ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags, @@ -2321,39 +2320,43 @@ enc_term(ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags, } static int -enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags, +enc_term_int(TTBEncodeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags, struct erl_off_heap_header** off_heap, Sint *reds, byte **res) { - DECLARE_ESTACK(s); - DECLARE_WSTACK(com); + DECLARE_WSTACK(s); Uint n; Uint i; Uint j; Uint* ptr; Eterm val; FloatDef f; - int count_reds = (p != NULL && reds != NULL); Sint r = 0; +#if HALFWORD_HEAP + UWord wobj; +#endif - if (count_reds) { - ESTACK_CHANGE_ALLOCATOR(s, ERTS_ALC_T_EXTRA_ROOT); - WSTACK_CHANGE_ALLOCATOR(com, ERTS_ALC_T_EXTRA_ROOT); + + if (ctx) { + WSTACK_CHANGE_ALLOCATOR(s, ERTS_ALC_T_SAVED_ESTACK); r = *reds; - } - if (p && p->extra_root) { /* restore saved stacks and byte pointer */ - ESTACK_RESTORE(s,p->extra_root[0].objv, p->extra_root[0].sz); - obj = ESTACK_POP(s); - WSTACK_RESTORE(com, p->extra_root[1].objv, p->extra_root[1].sz); - ep = (byte *) WSTACK_POP(com); + if (ctx->stack) { /* restore saved stacks and byte pointer */ + WSTACK_RESTORE(s, ctx->stack, ctx->stack_sz); + ep = ctx->ep; + obj = ctx->obj; + } } goto L_jump_start; outer_loop: - while (!ESTACK_ISEMPTY(s)) { - obj = ESTACK_POP(s); - switch (val = WSTACK_POP(com)) { + while (!WSTACK_ISEMPTY(s)) { +#if HALFWORD_HEAP + obj = (Eterm) (wobj = WSTACK_POP(s)); +#else + obj = WSTACK_POP(s); +#endif + switch (val = WSTACK_POP(s)) { case ENC_TERM: break; case ENC_ONE_CONS: @@ -2364,55 +2367,52 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla obj = CAR(cons); tl = CDR(cons); - WSTACK_PUSH(com, is_list(tl) ? ENC_ONE_CONS : ENC_TERM); - ESTACK_PUSH(s, tl); + WSTACK_PUSH(s, is_list(tl) ? ENC_ONE_CONS : ENC_TERM); + WSTACK_PUSH(s, tl); } break; case ENC_PATCH_FUN_SIZE: - /* obj will be discarded, it was NIL */ { - byte* size_p = (byte *) WSTACK_POP(com); +#if HALFWORD_HEAP + byte* size_p = (byte *) wobj; +#else + byte* size_p = (byte *) obj; +#endif put_int32(ep - size_p, size_p); } goto outer_loop; case ENC_LAST_ARRAY_ELEMENT: /* obj is the tuple */ { - Eterm* ptr = tuple_val(obj); - i = arityval(*ptr); - obj = ptr[i]; +#if HALFWORD_HEAP + Eterm* ptr = (Eterm *) wobj; +#else + Eterm* ptr = (Eterm *) obj; +#endif + obj = *ptr; } break; default: /* ENC_LAST_ARRAY_ELEMENT+1 and upwards */ { - Eterm* ptr = tuple_val(obj); - i = arityval(*ptr); - ESTACK_PUSH(s, obj); /* put back tuple and next element index */ - WSTACK_PUSH(com, val-1); - obj = ptr[i - (val - ENC_LAST_ARRAY_ELEMENT)]; /* the index is counting down */ +#if HALFWORD_HEAP + Eterm* ptr = (Eterm *) wobj; +#else + Eterm* ptr = (Eterm *) obj; +#endif + WSTACK_PUSH(s, val-1); + obj = *ptr++; + WSTACK_PUSH(s, (UWord)ptr); } break; } L_jump_start: - if (count_reds && --r == 0) { + if (ctx && --r == 0) { *reds = r; - ESTACK_PUSH(s,obj); /* push back current object, to be popped on restore */ - WSTACK_PUSH(com,((UWord) ep)); - if (p->extra_root == NULL) { - /* NB. Allocate an array of two "extra-roots", of which only the first element - is seen and handled by the GC. Index 1 holds the Wstack. */ - p->extra_root = erts_alloc(ERTS_ALC_T_EXTRA_ROOT, sizeof(ErlExtraRootSet)*2); - p->extra_root->objv = NULL; - p->extra_root->sz = 0; - p->extra_root->cleanup = cleanup_ttb_extra_root_2; - p->extra_root[1].objv = NULL; - p->extra_root[1].sz = 0; - p->extra_root[1].cleanup = NULL; /* Never used */ - } - ESTACK_SAVE(s, p->extra_root[0].objv, p->extra_root[0].sz); - WSTACK_SAVE(com, p->extra_root[1].objv, (p->extra_root[1].sz)); + ctx->obj = obj; + ctx->ep = ep; + WSTACK_SAVE(s, ctx->stack, ctx->stack_sz); return -1; } switch(tag_val_def(obj)) { @@ -2558,8 +2558,8 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla ep += 4; } if (i > 0) { - WSTACK_PUSH(com, ENC_LAST_ARRAY_ELEMENT+i-1); - ESTACK_PUSH(s, obj); + WSTACK_PUSH(s, ENC_LAST_ARRAY_ELEMENT+i-1); + WSTACK_PUSH(s, (UWord)ptr); } break; @@ -2703,9 +2703,8 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla int ei; *ep++ = NEW_FUN_EXT; - WSTACK_PUSH(com, (UWord) ep); /* Position for patching in size */ - WSTACK_PUSH(com, ENC_PATCH_FUN_SIZE); - ESTACK_PUSH(s,NIL); /* Will be thrown away */ + WSTACK_PUSH(s, ENC_PATCH_FUN_SIZE); + WSTACK_PUSH(s, (UWord) ep); /* Position for patching in size */ ep += 4; *ep = funp->arity; ep += 1; @@ -2722,8 +2721,8 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla fun_env: for (ei = funp->num_free-1; ei > 0; ei--) { - WSTACK_PUSH(com, ENC_TERM); - ESTACK_PUSH(s, (UWord) funp->env[ei]); + WSTACK_PUSH(s, ENC_TERM); + WSTACK_PUSH(s, (UWord) funp->env[ei]); } if (funp->num_free != 0) { obj = funp->env[0]; @@ -2766,13 +2765,12 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla break; } } - DESTROY_ESTACK(s); - DESTROY_WSTACK(com); - if (p && p->extra_root) { - cleanup_ttb_extra_root_2(p->extra_root); - p->extra_root = NULL; - } - if (count_reds) { + DESTROY_WSTACK(s); + if (ctx) { + if (ctx->stack) { + erts_free(ERTS_ALC_T_SAVED_ESTACK, ctx->stack); + ctx->stack = NULL; + } *reds = r; } *res = ep; @@ -3742,26 +3740,24 @@ static Uint encode_size_struct2(ErtsAtomCacheMap *acmp, Eterm obj, unsigned dfla } static int -encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj, +encode_size_struct_int(TTBSizeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj, unsigned dflags, Sint *reds, Uint *res) { DECLARE_ESTACK(s); Uint m, i, arity; Uint result = 0; - int count_reds = (p != NULL && reds != 0); Sint r = 0; - if (count_reds) { - ESTACK_CHANGE_ALLOCATOR(s, ERTS_ALC_T_EXTRA_ROOT); + if (ctx) { + ESTACK_CHANGE_ALLOCATOR(s, ERTS_ALC_T_SAVED_ESTACK); r = *reds; - } - - if (p && p->extra_root) { /* restore saved stack */ - ESTACK_RESTORE(s,p->extra_root->objv, p->extra_root->sz + 1); - result = ESTACK_POP(s); /*Untagged, beyond p->extra_root->sz */ - obj = ESTACK_POP(s); - } + if (ctx->stack) { /* restore saved stack */ + ESTACK_RESTORE(s, ctx->stack, ctx->stack_sz); + result = ctx->result; + obj = ctx->obj; + } + } goto L_jump_start; @@ -3787,18 +3783,11 @@ encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj, } L_jump_start: - if (count_reds && --r == 0) { + if (ctx && --r == 0) { *reds = r; - ESTACK_PUSH(s,obj); /* push back current object */ - ESTACK_PUSH(s,result); /* Untagged, will be out of GC reach */ - if (p->extra_root == NULL) { - p->extra_root = erts_alloc(ERTS_ALC_T_EXTRA_ROOT, sizeof(ErlExtraRootSet)); - p->extra_root->objv = NULL; - p->extra_root->sz = 0; - p->extra_root->cleanup = cleanup_ttb_extra_root; - } - ESTACK_SAVE(s, p->extra_root->objv, p->extra_root->sz); - --p->extra_root->sz; /* Hide result from GC */ + ctx->obj = obj; + ctx->result = result; + ESTACK_SAVE(s, ctx->stack, ctx->stack_sz); return -1; } switch (tag_val_def(obj)) { @@ -4001,11 +3990,11 @@ encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj, } DESTROY_ESTACK(s); - if (p && p->extra_root) { - cleanup_ttb_extra_root(p->extra_root); - p->extra_root = NULL; - } - if (count_reds) { + if (ctx) { + if (ctx->stack) { + erts_free(ERTS_ALC_T_SAVED_ESTACK, ctx->stack); + ctx->stack = NULL; + } *reds = r; } *res = result; -- cgit v1.2.3