void
erts_install_breakpoints(BpFunctions* f)
{
Uint i;
Uint n = f->matched;
BeamInstr br = (BeamInstr) BeamOp(op_i_generic_breakpoint);
for (i = 0; i < n; i++) {
BeamInstr* pc = f->matching[i].pc;
GenericBp* g = (GenericBp *) pc[-4];
if (*pc != br && g) {
Module* modp = f->matching[i].mod;
/*
* The breakpoint must be disabled in the active data
* (it will enabled later by switching bp indices),
* and enabled in the staging data.
*/
ASSERT(g->data[erts_active_bp_ix()].flags == 0);
ASSERT(g->data[erts_staging_bp_ix()].flags != 0);
/*
* The following write is not protected by any lock. We
* assume that the hardware guarantees that a write of an
* aligned word-size (or half-word) writes is atomic
* (i.e. that other processes executing this code will not
* see a half pointer).
*/
*pc = br;
modp->curr.num_breakpoints++;
}
}
}
void
erts_commit_staged_bp(void)
{
ErtsBpIndex staging = erts_staging_bp_ix();
ErtsBpIndex active = erts_active_bp_ix();
erts_smp_atomic32_set_nob(&erts_active_bp_index, staging);
erts_smp_atomic32_set_nob(&erts_staging_bp_index, active);
}
void
erts_clear_call_trace_bif(BeamInstr *pc, int local)
{
GenericBp* g = (GenericBp *) pc[-4];
if (g) {
Uint flags = local ? ERTS_BPF_LOCAL_TRACE : ERTS_BPF_GLOBAL_TRACE;
if (g->data[erts_staging_bp_ix()].flags & flags) {
clear_function_break(pc, flags);
}
}
}
void
erts_clear_call_trace_bif(ErtsCodeInfo *ci, int local)
{
GenericBp* g = ci->u.gen_bp;
if (g) {
Uint flags = local ? ERTS_BPF_LOCAL_TRACE : ERTS_BPF_GLOBAL_TRACE;
if (g->data[erts_staging_bp_ix()].flags & flags) {
clear_function_break(ci, flags);
}
}
}
static void
consolidate_bp_data(Module* modp, BeamInstr* pc, int local)
{
GenericBp* g = (GenericBp *) pc[-4];
GenericBpData* src;
GenericBpData* dst;
Uint flags;
if (g == 0) {
return;
}
src = &g->data[erts_active_bp_ix()];
dst = &g->data[erts_staging_bp_ix()];
/*
* The contents of the staging area may be out of date.
* Decrement all reference pointers.
*/
flags = dst->flags;
if (flags & (ERTS_BPF_LOCAL_TRACE|ERTS_BPF_GLOBAL_TRACE)) {
MatchSetUnref(dst->local_ms);
}
if (flags & ERTS_BPF_META_TRACE) {
bp_meta_unref(dst->meta_tracer);
MatchSetUnref(dst->meta_ms);
}
if (flags & ERTS_BPF_COUNT) {
bp_count_unref(dst->count);
}
if (flags & ERTS_BPF_TIME_TRACE) {
bp_time_unref(dst->time);
}
/*
* If all flags are zero, deallocate all breakpoint data.
*/
flags = dst->flags = src->flags;
if (flags == 0) {
if (modp) {
if (local) {
modp->curr.num_breakpoints--;
} else {
modp->curr.num_traced_exports--;
}
ASSERT(modp->curr.num_breakpoints >= 0);
ASSERT(modp->curr.num_traced_exports >= 0);
ASSERT(*pc != (BeamInstr) BeamOp(op_i_generic_breakpoint));
}
pc[-4] = 0;
Free(g);
return;
}
/*
* Copy the active data to the staging area (making it ready
* for the next time it will be used).
*/
if (flags & (ERTS_BPF_LOCAL_TRACE|ERTS_BPF_GLOBAL_TRACE)) {
dst->local_ms = src->local_ms;
MatchSetRef(dst->local_ms);
}
if (flags & ERTS_BPF_META_TRACE) {
dst->meta_tracer = src->meta_tracer;
erts_refc_inc(&dst->meta_tracer->refc, 1);
dst->meta_ms = src->meta_ms;
MatchSetRef(dst->meta_ms);
}
if (flags & ERTS_BPF_COUNT) {
dst->count = src->count;
erts_refc_inc(&dst->count->refc, 1);
}
if (flags & ERTS_BPF_TIME_TRACE) {
dst->time = src->time;
erts_refc_inc(&dst->time->refc, 1);
ASSERT(dst->time->hash);
}
}
