[PATCH v1 21/58] perf python: Expose brstack in sample event

[Ian Rogers]

Implement pyrf_branch_entry and pyrf_branch_stack for lazy
iteration over branch stack entries.

Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
 tools/perf/util/python.c | 163 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 163 insertions(+)

diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index 1e393f354ea0..52970c78106f 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -19,6 +19,7 @@
 #include "dso.h"
 #include "dwarf-regs.h"
 #include "event.h"
+#include "branch.h"
 #include "evlist.h"
 #include "evsel.h"
 #include "expr.h"
@@ -866,6 +867,150 @@ static PyObject *pyrf_sample_event__get_callchain(PyObject *self, void */*closur
 	return (PyObject *)pchain;
 }
 
+struct pyrf_branch_entry {
+	PyObject_HEAD
+	u64 from;
+	u64 to;
+	struct branch_flags flags;
+};
+
+static void pyrf_branch_entry__delete(struct pyrf_branch_entry *pentry)
+{
+	Py_TYPE(pentry)->tp_free((PyObject *)pentry);
+}
+
+static PyObject *pyrf_branch_entry__get_from(struct pyrf_branch_entry *pentry,
+					     void *closure __maybe_unused)
+{
+	return PyLong_FromUnsignedLongLong(pentry->from);
+}
+
+static PyObject *pyrf_branch_entry__get_to(struct pyrf_branch_entry *pentry,
+					   void *closure __maybe_unused)
+{
+	return PyLong_FromUnsignedLongLong(pentry->to);
+}
+
+static PyObject *pyrf_branch_entry__get_mispred(struct pyrf_branch_entry *pentry,
+						void *closure __maybe_unused)
+{
+	return PyBool_FromLong(pentry->flags.mispred);
+}
+
+static PyObject *pyrf_branch_entry__get_predicted(struct pyrf_branch_entry *pentry,
+						  void *closure __maybe_unused)
+{
+	return PyBool_FromLong(pentry->flags.predicted);
+}
+
+static PyObject *pyrf_branch_entry__get_in_tx(struct pyrf_branch_entry *pentry,
+					      void *closure __maybe_unused)
+{
+	return PyBool_FromLong(pentry->flags.in_tx);
+}
+
+static PyObject *pyrf_branch_entry__get_abort(struct pyrf_branch_entry *pentry,
+					      void *closure __maybe_unused)
+{
+	return PyBool_FromLong(pentry->flags.abort);
+}
+
+static PyObject *pyrf_branch_entry__get_cycles(struct pyrf_branch_entry *pentry,
+					       void *closure __maybe_unused)
+{
+	return PyLong_FromUnsignedLongLong(pentry->flags.cycles);
+}
+
+static PyObject *pyrf_branch_entry__get_type(struct pyrf_branch_entry *pentry,
+					     void *closure __maybe_unused)
+{
+	return PyLong_FromLong(pentry->flags.type);
+}
+
+static PyGetSetDef pyrf_branch_entry__getset[] = {
+	{ .name = "from",      .get = (getter)pyrf_branch_entry__get_from, },
+	{ .name = "to",        .get = (getter)pyrf_branch_entry__get_to, },
+	{ .name = "mispred",   .get = (getter)pyrf_branch_entry__get_mispred, },
+	{ .name = "predicted", .get = (getter)pyrf_branch_entry__get_predicted, },
+	{ .name = "in_tx",     .get = (getter)pyrf_branch_entry__get_in_tx, },
+	{ .name = "abort",     .get = (getter)pyrf_branch_entry__get_abort, },
+	{ .name = "cycles",    .get = (getter)pyrf_branch_entry__get_cycles, },
+	{ .name = "type",      .get = (getter)pyrf_branch_entry__get_type, },
+	{ .name = NULL, },
+};
+
+static PyTypeObject pyrf_branch_entry__type = {
+	PyVarObject_HEAD_INIT(NULL, 0)
+	.tp_name	= "perf.branch_entry",
+	.tp_basicsize	= sizeof(struct pyrf_branch_entry),
+	.tp_dealloc	= (destructor)pyrf_branch_entry__delete,
+	.tp_flags	= Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE,
+	.tp_doc		= "perf branch entry object.",
+	.tp_getset	= pyrf_branch_entry__getset,
+};
+
+struct pyrf_branch_stack {
+	PyObject_HEAD
+	struct pyrf_event *pevent;
+	u64 pos;
+};
+
+static void pyrf_branch_stack__delete(struct pyrf_branch_stack *pstack)
+{
+	Py_XDECREF(pstack->pevent);
+	Py_TYPE(pstack)->tp_free((PyObject *)pstack);
+}
+
+static PyObject *pyrf_branch_stack__next(struct pyrf_branch_stack *pstack)
+{
+	struct pyrf_branch_entry *pentry;
+	struct branch_stack *bs = pstack->pevent->sample.branch_stack;
+	struct branch_entry *entries = perf_sample__branch_entries(&pstack->pevent->sample);
+
+	if (!bs || !entries || pstack->pos >= bs->nr)
+		return NULL;
+
+	pentry = PyObject_New(struct pyrf_branch_entry, &pyrf_branch_entry__type);
+	if (!pentry)
+		return NULL;
+
+	pentry->from = entries[pstack->pos].from;
+	pentry->to = entries[pstack->pos].to;
+	pentry->flags = entries[pstack->pos].flags;
+
+	pstack->pos++;
+	return (PyObject *)pentry;
+}
+
+static PyTypeObject pyrf_branch_stack__type = {
+	PyVarObject_HEAD_INIT(NULL, 0)
+	.tp_name	= "perf.branch_stack",
+	.tp_basicsize	= sizeof(struct pyrf_branch_stack),
+	.tp_dealloc	= (destructor)pyrf_branch_stack__delete,
+	.tp_flags	= Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE,
+	.tp_doc		= "perf branch stack object.",
+	.tp_iter	= PyObject_SelfIter,
+	.tp_iternext	= (iternextfunc)pyrf_branch_stack__next,
+};
+
+static PyObject *pyrf_sample_event__get_brstack(PyObject *self, void *closure __maybe_unused)
+{
+	struct pyrf_event *pevent = (void *)self;
+	struct pyrf_branch_stack *pstack;
+
+	if (!pevent->sample.branch_stack)
+		Py_RETURN_NONE;
+
+	pstack = PyObject_New(struct pyrf_branch_stack, &pyrf_branch_stack__type);
+	if (!pstack)
+		return NULL;
+
+	Py_INCREF(pevent);
+	pstack->pevent = pevent;
+	pstack->pos = 0;
+	return (PyObject *)pstack;
+}
+
 static PyObject*
 pyrf_sample_event__getattro(struct pyrf_event *pevent, PyObject *attr_name)
 {
@@ -886,6 +1031,12 @@ static PyGetSetDef pyrf_sample_event__getset[] = {
 		.set = NULL,
 		.doc = "event callchain.",
 	},
+	{
+		.name = "brstack",
+		.get = pyrf_sample_event__get_brstack,
+		.set = NULL,
+		.doc = "event branch stack.",
+	},
 	{
 		.name = "raw_buf",
 		.get = (getter)pyrf_sample_event__get_raw_buf,
@@ -1066,6 +1217,12 @@ static int pyrf_event__setup_types(void)
 	err = PyType_Ready(&pyrf_callchain__type);
 	if (err < 0)
 		goto out;
+	err = PyType_Ready(&pyrf_branch_entry__type);
+	if (err < 0)
+		goto out;
+	err = PyType_Ready(&pyrf_branch_stack__type);
+	if (err < 0)
+		goto out;
 out:
 	return err;
 }
@@ -3434,6 +3591,12 @@ PyMODINIT_FUNC PyInit_perf(void)
 	Py_INCREF(&pyrf_session__type);
 	PyModule_AddObject(module, "session", (PyObject *)&pyrf_session__type);
 
+	Py_INCREF(&pyrf_branch_entry__type);
+	PyModule_AddObject(module, "branch_entry", (PyObject *)&pyrf_branch_entry__type);
+
+	Py_INCREF(&pyrf_branch_stack__type);
+	PyModule_AddObject(module, "branch_stack", (PyObject *)&pyrf_branch_stack__type);
+
 	dict = PyModule_GetDict(module);
 	if (dict == NULL)
 		goto error;
-- 
2.54.0.rc1.513.gad8abe7a5a-goog