Skip to content

Unchecked backtrace APIs for profilers and crash reporter #14648

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
XrXr merged 1 commit into from
Sep 25, 2025
Merged

Unchecked backtrace APIs for profilers and crash reporter #14648

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 5 additions & 3 deletions vm_backtrace.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1745,14 +1745,14 @@ thread_profile_frames(rb_execution_context_t *ec, int start, int limit, VALUE *b
end_cfp = RUBY_VM_NEXT_CONTROL_FRAME(end_cfp);

for (i=0; i<limit && cfp != end_cfp; cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(cfp)) {
if (VM_FRAME_RUBYFRAME_P(cfp) && cfp->pc != 0) {
if (VM_FRAME_RUBYFRAME_P_UNCHECKED(cfp) && cfp->pc != 0) {
if (start > 0) {
start--;
continue;
}

/* record frame info */
cme = rb_vm_frame_method_entry(cfp);
cme = rb_vm_frame_method_entry_unchecked(cfp);
if (cme && cme->def->type == VM_METHOD_TYPE_ISEQ) {
buff[i] = (VALUE)cme;
}
Expand All @@ -1770,6 +1770,8 @@ thread_profile_frames(rb_execution_context_t *ec, int start, int limit, VALUE *b
// before entering a non-leaf method (so that `caller` will work),
// so only the topmost frame could possibly have an out-of-date PC.
// ZJIT doesn't set `cfp->jit_return`, so it's not a reliable signal.
// TODO(zjit): lightweight frames potentially makes more than
// the top most frame invalid.
//
// Avoid passing invalid PC to calc_lineno() to avoid crashing.
if (cfp == top && (pc < iseq_encoded || pc > pc_end)) {
Expand All @@ -1783,7 +1785,7 @@ thread_profile_frames(rb_execution_context_t *ec, int start, int limit, VALUE *b
i++;
}
else {
cme = rb_vm_frame_method_entry(cfp);
cme = rb_vm_frame_method_entry_unchecked(cfp);
if (cme && cme->def->type == VM_METHOD_TYPE_CFUNC) {
if (start > 0) {
start--;
Expand Down
46 changes: 45 additions & 1 deletion vm_core.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1449,12 +1449,25 @@ VM_ENV_FLAGS(const VALUE *ep, long flag)
return flags & flag;
}

static inline unsigned long
VM_ENV_FLAGS_UNCHECKED(const VALUE *ep, long flag)
{
VALUE flags = ep[VM_ENV_DATA_INDEX_FLAGS];
return flags & flag;
}

static inline unsigned long
VM_FRAME_TYPE(const rb_control_frame_t *cfp)
{
return VM_ENV_FLAGS(cfp->ep, VM_FRAME_MAGIC_MASK);
}

static inline unsigned long
VM_FRAME_TYPE_UNCHECKED(const rb_control_frame_t *cfp)
{
return VM_ENV_FLAGS_UNCHECKED(cfp->ep, VM_FRAME_MAGIC_MASK);
}

static inline int
VM_FRAME_LAMBDA_P(const rb_control_frame_t *cfp)
{
Expand All @@ -1473,6 +1486,12 @@ VM_FRAME_FINISHED_P(const rb_control_frame_t *cfp)
return VM_ENV_FLAGS(cfp->ep, VM_FRAME_FLAG_FINISH) != 0;
}

static inline int
VM_FRAME_FINISHED_P_UNCHECKED(const rb_control_frame_t *cfp)
{
return VM_ENV_FLAGS_UNCHECKED(cfp->ep, VM_FRAME_FLAG_FINISH) != 0;
}

static inline int
VM_FRAME_BMETHOD_P(const rb_control_frame_t *cfp)
{
Expand All @@ -1498,12 +1517,24 @@ VM_FRAME_CFRAME_P(const rb_control_frame_t *cfp)
return cframe_p;
}

static inline int
VM_FRAME_CFRAME_P_UNCHECKED(const rb_control_frame_t *cfp)
{
return VM_ENV_FLAGS_UNCHECKED(cfp->ep, VM_FRAME_FLAG_CFRAME) != 0;
}

static inline int
VM_FRAME_RUBYFRAME_P(const rb_control_frame_t *cfp)
{
return !VM_FRAME_CFRAME_P(cfp);
}

static inline int
VM_FRAME_RUBYFRAME_P_UNCHECKED(const rb_control_frame_t *cfp)
{
return !VM_FRAME_CFRAME_P_UNCHECKED(cfp);
}

static inline int
VM_FRAME_NS_SWITCH_P(const rb_control_frame_t *cfp)
{
Expand All @@ -1522,11 +1553,23 @@ VM_ENV_LOCAL_P(const VALUE *ep)
return VM_ENV_FLAGS(ep, VM_ENV_FLAG_LOCAL) ? 1 : 0;
}

static inline int
VM_ENV_LOCAL_P_UNCHECKED(const VALUE *ep)
{
return VM_ENV_FLAGS_UNCHECKED(ep, VM_ENV_FLAG_LOCAL) ? 1 : 0;
}

static inline const VALUE *
VM_ENV_PREV_EP_UNCHECKED(const VALUE *ep)
{
return GC_GUARDED_PTR_REF(ep[VM_ENV_DATA_INDEX_SPECVAL]);
}

static inline const VALUE *
VM_ENV_PREV_EP(const VALUE *ep)
{
VM_ASSERT(VM_ENV_LOCAL_P(ep) == 0);
return GC_GUARDED_PTR_REF(ep[VM_ENV_DATA_INDEX_SPECVAL]);
return VM_ENV_PREV_EP_UNCHECKED(ep);
}

static inline VALUE
Expand Down Expand Up @@ -1934,6 +1977,7 @@ void rb_gc_mark_machine_context(const rb_execution_context_t *ec);
rb_cref_t *rb_vm_rewrite_cref(rb_cref_t *node, VALUE old_klass, VALUE new_klass);

const rb_callable_method_entry_t *rb_vm_frame_method_entry(const rb_control_frame_t *cfp);
const rb_callable_method_entry_t *rb_vm_frame_method_entry_unchecked(const rb_control_frame_t *cfp);

#define sysstack_error GET_VM()->special_exceptions[ruby_error_sysstack]

Expand Down
12 changes: 7 additions & 5 deletions vm_dump.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -61,14 +61,14 @@ control_frame_dump(const rb_execution_context_t *ec, const rb_control_frame_t *c
const char *magic, *iseq_name = "-", *selfstr = "-", *biseq_name = "-";
VALUE tmp;
const rb_iseq_t *iseq = NULL;
const rb_callable_method_entry_t *me = rb_vm_frame_method_entry(cfp);
const rb_callable_method_entry_t *me = rb_vm_frame_method_entry_unchecked(cfp);

if (ep < 0 || (size_t)ep > ec->vm_stack_size) {
ep = (ptrdiff_t)cfp->ep;
ep_in_heap = 'p';
}

switch (VM_FRAME_TYPE(cfp)) {
switch (VM_FRAME_TYPE_UNCHECKED(cfp)) {
case VM_FRAME_MAGIC_TOP:
magic = "TOP";
break;
Expand Down Expand Up @@ -128,7 +128,9 @@ control_frame_dump(const rb_execution_context_t *ec, const rb_control_frame_t *c
iseq = cfp->iseq;
pc = cfp->pc - ISEQ_BODY(iseq)->iseq_encoded;
iseq_name = RSTRING_PTR(ISEQ_BODY(iseq)->location.label);
line = rb_vm_get_sourceline(cfp);
if (pc >= 0 && pc <= ISEQ_BODY(iseq)->iseq_size) {
line = rb_vm_get_sourceline(cfp);
}
if (line) {
snprintf(posbuf, MAX_POSBUF, "%s:%d", RSTRING_PTR(rb_iseq_path(iseq)), line);
}
Expand All @@ -138,7 +140,7 @@ control_frame_dump(const rb_execution_context_t *ec, const rb_control_frame_t *c
}
}
}
else if (me != NULL) {
else if (me != NULL && IMEMO_TYPE_P(me, imemo_ment)) {
iseq_name = rb_id2name(me->def->original_id);
snprintf(posbuf, MAX_POSBUF, ":%s", iseq_name);
line = -1;
Expand All @@ -158,7 +160,7 @@ control_frame_dump(const rb_execution_context_t *ec, const rb_control_frame_t *c
if (line) {
kprintf(" %s", posbuf);
}
if (VM_FRAME_FINISHED_P(cfp)) {
if (VM_FRAME_FINISHED_P_UNCHECKED(cfp)) {
kprintf(" [FINISH]");
}
if (0) {
Expand Down
33 changes: 33 additions & 0 deletions vm_insnhelper.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -761,6 +761,25 @@ check_method_entry(VALUE obj, int can_be_svar)
}
}

static rb_callable_method_entry_t *
env_method_entry_unchecked(VALUE obj, int can_be_svar)
{
if (obj == Qfalse) return NULL;

switch (imemo_type(obj)) {
case imemo_ment:
return (rb_callable_method_entry_t *)obj;
case imemo_cref:
return NULL;
case imemo_svar:
if (can_be_svar) {
return env_method_entry_unchecked(((struct vm_svar *)obj)->cref_or_me, FALSE);
}
default:
return NULL;
}
}

const rb_callable_method_entry_t *
rb_vm_frame_method_entry(const rb_control_frame_t *cfp)
{
Expand All @@ -775,6 +794,20 @@ rb_vm_frame_method_entry(const rb_control_frame_t *cfp)
return check_method_entry(ep[VM_ENV_DATA_INDEX_ME_CREF], TRUE);
}

const rb_callable_method_entry_t *
rb_vm_frame_method_entry_unchecked(const rb_control_frame_t *cfp)
{
const VALUE *ep = cfp->ep;
rb_callable_method_entry_t *me;

while (!VM_ENV_LOCAL_P_UNCHECKED(ep)) {
if ((me = env_method_entry_unchecked(ep[VM_ENV_DATA_INDEX_ME_CREF], FALSE)) != NULL) return me;
ep = VM_ENV_PREV_EP_UNCHECKED(ep);
}

return env_method_entry_unchecked(ep[VM_ENV_DATA_INDEX_ME_CREF], TRUE);
}

static const rb_iseq_t *
method_entry_iseqptr(const rb_callable_method_entry_t *me)
{
Expand Down
Loading