static int any_heap_refs(Eterm* start, Eterm* end, char* mod_start, Uint mod_size) { Eterm* p; Eterm val; for (p = start; p < end; p++) { val = *p; switch (primary_tag(val)) { case TAG_PRIMARY_BOXED: case TAG_PRIMARY_LIST: if (ErtsInArea(val, mod_start, mod_size)) { return 1; } break; case TAG_PRIMARY_HEADER: if (!header_is_transparent(val)) { Eterm* new_p; if (header_is_bin_matchstate(val)) { ErlBinMatchState *ms = (ErlBinMatchState*) p; ErlBinMatchBuffer *mb = &(ms->mb); if (ErtsInArea(mb->orig, mod_start, mod_size)) { return 1; } } new_p = p + thing_arityval(val); ASSERT(start <= new_p && new_p < end); p = new_p; } } } return 0; }
static Uint hfrag_literal_size(Eterm* start, Eterm* end, char* lit_start, Uint lit_size) { Eterm* p; Eterm val; Uint sz = 0; for (p = start; p < end; p++) { val = *p; switch (primary_tag(val)) { case TAG_PRIMARY_BOXED: case TAG_PRIMARY_LIST: if (ErtsInArea(val, lit_start, lit_size)) { sz += size_object(val); } break; case TAG_PRIMARY_HEADER: if (!header_is_transparent(val)) { Eterm* new_p; if (header_is_bin_matchstate(val)) { ErlBinMatchState *ms = (ErlBinMatchState*) p; ErlBinMatchBuffer *mb = &(ms->mb); if (ErtsInArea(mb->orig, lit_start, lit_size)) { sz += size_object(mb->orig); } } new_p = p + thing_arityval(val); ASSERT(start <= new_p && new_p < end); p = new_p; } } } return sz; }
static ERTS_INLINE int check_mod_funs(Process *p, ErlOffHeap *off_heap, char *area, size_t area_size) { struct erl_off_heap_header* oh; for (oh = off_heap->first; oh; oh = oh->next) { if (thing_subtag(oh->thing_word) == FUN_SUBTAG) { ErlFunThing* funp = (ErlFunThing*) oh; if (ErtsInArea(funp->fe->address, area, area_size)) return !0; } } return 0; }
static void hfrag_literal_copy(Eterm **hpp, ErlOffHeap *ohp, Eterm *start, Eterm *end, char *lit_start, Uint lit_size) { Eterm* p; Eterm val; Uint sz; for (p = start; p < end; p++) { val = *p; switch (primary_tag(val)) { case TAG_PRIMARY_BOXED: case TAG_PRIMARY_LIST: if (ErtsInArea(val, lit_start, lit_size)) { sz = size_object(val); val = copy_struct(val, sz, hpp, ohp); *p = val; } break; case TAG_PRIMARY_HEADER: if (!header_is_transparent(val)) { Eterm* new_p; /* matchstate in message, not possible. */ if (header_is_bin_matchstate(val)) { ErlBinMatchState *ms = (ErlBinMatchState*) p; ErlBinMatchBuffer *mb = &(ms->mb); if (ErtsInArea(mb->orig, lit_start, lit_size)) { sz = size_object(mb->orig); mb->orig = copy_struct(mb->orig, sz, hpp, ohp); } } new_p = p + thing_arityval(val); ASSERT(start <= new_p && new_p < end); p = new_p; } } } }
static int any_heap_ref_ptrs(Eterm* start, Eterm* end, char* mod_start, Uint mod_size) { Eterm* p; Eterm val; for (p = start; p < end; p++) { val = *p; switch (primary_tag(val)) { case TAG_PRIMARY_BOXED: case TAG_PRIMARY_LIST: if (ErtsInArea(val, mod_start, mod_size)) { return 1; } break; } } return 0; }
static Eterm check_process_code(Process* rp, Module* modp, Uint flags, int *redsp, int fcalls) { BeamInstr* start; char* literals; Uint lit_bsize; char* mod_start; Uint mod_size; Eterm* sp; int done_gc = 0; int need_gc = 0; ErtsMessage *msgp; ErlHeapFragment *hfrag; #define ERTS_ORDINARY_GC__ (1 << 0) #define ERTS_LITERAL_GC__ (1 << 1) /* * Pick up limits for the module. */ start = (BeamInstr*) modp->old.code_hdr; mod_start = (char *) start; mod_size = modp->old.code_length; /* * Check if current instruction or continuation pointer points into module. */ if (ErtsInArea(rp->i, mod_start, mod_size) || ErtsInArea(rp->cp, mod_start, mod_size)) { return am_true; } /* * Check all continuation pointers stored on the stack. */ for (sp = rp->stop; sp < STACK_START(rp); sp++) { if (is_CP(*sp) && ErtsInArea(cp_val(*sp), mod_start, mod_size)) { return am_true; } } /* * Check all continuation pointers stored in stackdump * and clear exception stackdump if there is a pointer * to the module. */ if (rp->ftrace != NIL) { struct StackTrace *s; ASSERT(is_list(rp->ftrace)); s = (struct StackTrace *) big_val(CDR(list_val(rp->ftrace))); if ((s->pc && ErtsInArea(s->pc, mod_start, mod_size)) || (s->current && ErtsInArea(s->current, mod_start, mod_size))) { rp->freason = EXC_NULL; rp->fvalue = NIL; rp->ftrace = NIL; } else { int i; for (i = 0; i < s->depth; i++) { if (ErtsInArea(s->trace[i], mod_start, mod_size)) { rp->freason = EXC_NULL; rp->fvalue = NIL; rp->ftrace = NIL; break; } } } } if (rp->flags & F_DISABLE_GC) { /* * Cannot proceed. Process has disabled gc in order to * safely leave inconsistent data on the heap and/or * off heap lists. Need to wait for gc to be enabled * again. */ return THE_NON_VALUE; } /* * Message queue can contains funs, but (at least currently) no * literals. If we got references to this module from the message * queue, a GC cannot remove these... */ erts_smp_proc_lock(rp, ERTS_PROC_LOCK_MSGQ); ERTS_SMP_MSGQ_MV_INQ2PRIVQ(rp); erts_smp_proc_unlock(rp, ERTS_PROC_LOCK_MSGQ); literals = (char*) modp->old.code_hdr->literals_start; lit_bsize = (char*) modp->old.code_hdr->literals_end - literals; for (msgp = rp->msg.first; msgp; msgp = msgp->next) { if (msgp->data.attached == ERTS_MSG_COMBINED_HFRAG) hfrag = &msgp->hfrag; else if (is_value(ERL_MESSAGE_TERM(msgp)) && msgp->data.heap_frag) hfrag = msgp->data.heap_frag; else continue; for (; hfrag; hfrag = hfrag->next) { if (check_mod_funs(rp, &hfrag->off_heap, mod_start, mod_size)) return am_true; /* Should not contain any literals... */ ASSERT(!any_heap_refs(&hfrag->mem[0], &hfrag->mem[hfrag->used_size], literals, lit_bsize)); } } while (1) { /* Check heap, stack etc... */ if (check_mod_funs(rp, &rp->off_heap, mod_start, mod_size)) goto try_gc; if (!(flags & ERTS_CPC_COPY_LITERALS)) { /* Process ok. May contain old literals but we will be called * again before module is purged. */ return am_false; } if (any_heap_ref_ptrs(&rp->fvalue, &rp->fvalue+1, literals, lit_bsize)) { rp->freason = EXC_NULL; rp->fvalue = NIL; rp->ftrace = NIL; } if (any_heap_ref_ptrs(rp->stop, rp->hend, literals, lit_bsize)) goto try_literal_gc; if (any_heap_refs(rp->heap, rp->htop, literals, lit_bsize)) goto try_literal_gc; if (any_heap_refs(rp->old_heap, rp->old_htop, literals, lit_bsize)) goto try_literal_gc; /* Check dictionary */ if (rp->dictionary) { Eterm* start = ERTS_PD_START(rp->dictionary); Eterm* end = start + ERTS_PD_SIZE(rp->dictionary); if (any_heap_ref_ptrs(start, end, literals, lit_bsize)) goto try_literal_gc; } /* Check heap fragments */ for (hfrag = rp->mbuf; hfrag; hfrag = hfrag->next) { Eterm *hp, *hp_end; /* Off heap lists should already have been moved into process */ ASSERT(!check_mod_funs(rp, &hfrag->off_heap, mod_start, mod_size)); hp = &hfrag->mem[0]; hp_end = &hfrag->mem[hfrag->used_size]; if (any_heap_refs(hp, hp_end, literals, lit_bsize)) goto try_literal_gc; } #ifdef DEBUG /* * Message buffer fragments should not have any references * to literals, and off heap lists should already have * been moved into process off heap structure. */ for (msgp = rp->msg_frag; msgp; msgp = msgp->next) { if (msgp->data.attached == ERTS_MSG_COMBINED_HFRAG) hfrag = &msgp->hfrag; else hfrag = msgp->data.heap_frag; for (; hfrag; hfrag = hfrag->next) { Eterm *hp, *hp_end; ASSERT(!check_mod_funs(rp, &hfrag->off_heap, mod_start, mod_size)); hp = &hfrag->mem[0]; hp_end = &hfrag->mem[hfrag->used_size]; ASSERT(!any_heap_refs(hp, hp_end, literals, lit_bsize)); } } #endif return am_false; try_literal_gc: need_gc |= ERTS_LITERAL_GC__; try_gc: need_gc |= ERTS_ORDINARY_GC__; if ((done_gc & need_gc) == need_gc) return am_true; if (!(flags & ERTS_CPC_ALLOW_GC)) return am_aborted; need_gc &= ~done_gc; /* * Try to get rid of literals by by garbage collecting. * Clear both fvalue and ftrace. */ rp->freason = EXC_NULL; rp->fvalue = NIL; rp->ftrace = NIL; if (need_gc & ERTS_ORDINARY_GC__) { FLAGS(rp) |= F_NEED_FULLSWEEP; *redsp += erts_garbage_collect_nobump(rp, 0, rp->arg_reg, rp->arity, fcalls); done_gc |= ERTS_ORDINARY_GC__; } if (need_gc & ERTS_LITERAL_GC__) { struct erl_off_heap_header* oh; oh = modp->old.code_hdr->literals_off_heap; *redsp += lit_bsize / 64; /* Need, better value... */ erts_garbage_collect_literals(rp, (Eterm*)literals, lit_bsize, oh); done_gc |= ERTS_LITERAL_GC__; } need_gc = 0; } #undef ERTS_ORDINARY_GC__ #undef ERTS_LITERAL_GC__ }
static Eterm check_process_code(Process* rp, Module* modp, int *redsp, int fcalls) { BeamInstr* start; char* mod_start; Uint mod_size; Eterm* sp; #ifdef HIPE void *nat_start = NULL; Uint nat_size = 0; #endif *redsp += 1; /* * Pick up limits for the module. */ start = (BeamInstr*) modp->old.code_hdr; mod_start = (char *) start; mod_size = modp->old.code_length; /* * Check if current instruction or continuation pointer points into module. */ if (ErtsInArea(rp->i, mod_start, mod_size) || ErtsInArea(rp->cp, mod_start, mod_size)) { return am_true; } *redsp += (STACK_START(rp) - rp->stop) / 32; /* * Check all continuation pointers stored on the stack. */ for (sp = rp->stop; sp < STACK_START(rp); sp++) { if (is_CP(*sp) && ErtsInArea(cp_val(*sp), mod_start, mod_size)) { return am_true; } } #ifdef HIPE /* * Check all continuation pointers stored on the native stack if the module * has native code. */ if (modp->old.hipe_code) { nat_start = modp->old.hipe_code->text_segment; nat_size = modp->old.hipe_code->text_segment_size; if (nat_size && nstack_any_cps_in_segment(rp, nat_start, nat_size)) { return am_true; } } #endif /* * Check all continuation pointers stored in stackdump * and clear exception stackdump if there is a pointer * to the module. */ if (rp->ftrace != NIL) { struct StackTrace *s; ASSERT(is_list(rp->ftrace)); s = (struct StackTrace *) big_val(CDR(list_val(rp->ftrace))); if ((s->pc && ErtsInArea(s->pc, mod_start, mod_size)) || (s->current && ErtsInArea(s->current, mod_start, mod_size))) { rp->freason = EXC_NULL; rp->fvalue = NIL; rp->ftrace = NIL; } else { int i; char *area_start = mod_start; Uint area_size = mod_size; #ifdef HIPE if (rp->freason & EXF_NATIVE) { area_start = nat_start; area_size = nat_size; } #endif for (i = 0; i < s->depth; i++) { if (ErtsInArea(s->trace[i], area_start, area_size)) { rp->freason = EXC_NULL; rp->fvalue = NIL; rp->ftrace = NIL; break; } } } } return am_false; }