From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dy1-f201.google.com (mail-dy1-f201.google.com [74.125.82.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8769148AE03 for ; Fri, 5 Jun 2026 07:41:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780645266; cv=none; b=toJ4AtrvuYQFwN/dsblLtsQc3IDLW+OhGiGxLN0ajfZN/ph0J8U7zaMDOh3LyGtkiDZysejl2R1CAHKI9XgYBb3xmSQAtNaM7lpeVfiPaf4dQCZ3vIXIykWwq1lY9IZUNiHsCj2Ygz84toiGcYgsMv2P0Jt3KBwFqiWH/tms62g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780645266; c=relaxed/simple; bh=xh3IHkMcde6zuAqOHPK7BRA0GbARSVuODpAyNQneOc0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=OEyfnvG3U4cGL1tMwQCfpaiKs6rq1OqR6uq+PAaTDgVW+micuyN3u8X8WKls4BSe05X+wUpfGoZ0I5ER5RZo80uNv5Uoftv2/dhGLi4A/OOjkrqmCJC3/vlE6ra55wFVsW3EwrTvOQV28yiK5uqgHK4xy3+i4S8K4mZ+SsVl4Ao= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=opZsnB/K; arc=none smtp.client-ip=74.125.82.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="opZsnB/K" Received: by mail-dy1-f201.google.com with SMTP id 5a478bee46e88-30762d67a64so2209299eec.0 for ; Fri, 05 Jun 2026 00:41:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1780645262; x=1781250062; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=voLKjjU6OoMtJ62Uq8JeIHAZdLKiX0fx4p+oX06Fbac=; b=opZsnB/K4vZDw9e8IUwrBoSgnjjT7YydN68VKxVqCunkSCQ1scGHy8VPvYq+hIFrk8 ljc75GzIMKG5tA5KIguX/U5DRlTuisfhUr12VX2siJdT7ppNZa/6ltIAf7JnegpqEF/O IjFpGH6FmCYmy2za/3kX6hctf6hozOGlQ8+Q/4tggWHL4rDx3zOINfjJKJoT86QQSlxN NN20mDjzazMlLE5qqKOkXCEGnfy3CL5FiCmdgjwxw/ckcryRtheRIXtipJTEYJinAjZF PCxNM5eAdfK5MjM8+kNOkQpL11zd0WAzGstMqhhBrYYIcSoQwDllIkSCADSinuQqaNHu wTjw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780645262; x=1781250062; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=voLKjjU6OoMtJ62Uq8JeIHAZdLKiX0fx4p+oX06Fbac=; b=CzoHdoPZgyTq+avhycSPvTPBAprV5feV9THXY5ERaQ3BcLhJ/iK0rjld92IJpWBH+Z YQjycQZLLOlV+HeCDqf9S61NTgSafb2nm6XtgXSDCaerAeFpDQTm6G83ZPY45VirZSS7 9C/H4GXEyS+mR7rw8/1O/p6pM6jHy2Y6Rgy8yzANiT6GJkDVi2eBBt3KRknDUi1TFFwp A/uKjNJufHhb276g/gzH7z8YnAWJr6BpTlZaqf8bQxpaCVPrkEFc866hkXGUJkfGDrOa VosZeNMxy3Iz5Y5Jbg18Og9l1POibmuWA3mWS/nckzAbNncsEY+6ULWUa4QSsN3Do6m/ cCsQ== X-Forwarded-Encrypted: i=1; AFNElJ/Y7qha435EQTd9vAOoXJNijInf60KOgDPKMfDlAor5ZTmxYdN+3wLRWOeu3GH0r/NcDReoiBMtfsYg6k87vamt@vger.kernel.org X-Gm-Message-State: AOJu0YxhnYurOZXqOv/rsF/EGcts+1mmhOGQLwRpISS4kHnywY74P6ff oISclfoeW3lWlOHc4uoGDhnuKAbU9MQBsf4A9iX4rCxKOaGj9SBYXZAl/GM9V7jjXgEBeAAxih8 V/kU5woahTw== X-Received: from dyvt1.prod.google.com ([2002:a05:7301:d801:b0:304:d771:74aa]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7300:d70d:b0:304:5a9c:6479 with SMTP id 5a478bee46e88-3077b2d14aemr1110704eec.9.1780645261499; Fri, 05 Jun 2026 00:41:01 -0700 (PDT) Date: Fri, 5 Jun 2026 00:39:59 -0700 In-Reply-To: <20260605074003.1730715-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260522220435.2378363-1-irogers@google.com> <20260605074003.1730715-1-irogers@google.com> X-Mailer: git-send-email 2.54.0.1032.g2f8565e1d1-goog Message-ID: <20260605074003.1730715-16-irogers@google.com> Subject: [PATCH v10 15/19] perf python: Expose brstack in sample event From: Ian Rogers To: irogers@google.com, acme@kernel.org, namhyung@kernel.org Cc: adrian.hunter@intel.com, alice.mei.rogers@gmail.com, dapeng1.mi@linux.intel.com, james.clark@linaro.org, leo.yan@linux.dev, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tmricht@linux.ibm.com Content-Type: text/plain; charset="UTF-8" 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 --- v2: 1. Avoided Keyword Collision: Renamed the properties "from" and "to" to "from_ip" and "to_ip" in pyrf_branch_entry__getset[] to prevent syntax errors in Python. 2. Eager Branch Stack Resolution: Updated pyrf_session_tool__sample() to allocate and copy the branch stack entries eagerly when the event is processed, instead of deferring it to iteration time. This avoids reading from potentially overwritten or unmapped mmap buffers. 3. Updated Iterators: Updated pyrf_branch_stack and pyrf_branch_stack__next() to use the copied entries rather than pointing directly to the sample's buffer. 4. Avoided Reference Leak on Init Failure: Added proper error checking for PyModule_AddObject() in the module initialization function, decrementing references on failure. v6: - Moved branch stack resolution from `session_tool__sample` to `pyrf_event__new`. --- tools/perf/util/python.c | 197 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 197 insertions(+) diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c index 2b9de9c10ee2..7265e2dcd60e 100644 --- a/tools/perf/util/python.c +++ b/tools/perf/util/python.c @@ -22,6 +22,7 @@ #include "debug.h" #include "dso.h" #include "event.h" +#include "branch.h" #include "evlist.h" #include "evsel.h" #include "expr.h" @@ -87,6 +88,8 @@ struct pyrf_event { bool al_resolved; /** @callchain: Resolved callchain, eagerly computed if requested. */ PyObject *callchain; + /** @brstack: Resolved branch stack, eagerly computed if requested. */ + PyObject *brstack; /** @event: The underlying perf_event that may be in a file or ring buffer. */ union perf_event event; }; @@ -125,6 +128,7 @@ static void pyrf_event__delete(struct pyrf_event *pevent) if (pevent->al_resolved) addr_location__exit(&pevent->al); Py_XDECREF(pevent->callchain); + Py_XDECREF(pevent->brstack); perf_sample__exit(&pevent->sample); Py_TYPE(pevent)->tp_free((PyObject *)pevent); } @@ -992,6 +996,153 @@ static PyObject *pyrf_sample_event__get_callchain(PyObject *self, void *closure return pevent->callchain; } +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_ip", .get = (getter)pyrf_branch_entry__get_from, }, + { .name = "to_ip", .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 branch_entry *entries; + u64 nr; +}; + +static void pyrf_branch_stack__delete(struct pyrf_branch_stack *pstack) +{ + free(pstack->entries); + Py_TYPE(pstack)->tp_free((PyObject *)pstack); +} + +static Py_ssize_t pyrf_branch_stack__length(PyObject *obj) +{ + struct pyrf_branch_stack *pstack = (void *)obj; + return pstack->nr; +} + +static PyObject *pyrf_branch_stack__item(PyObject *obj, Py_ssize_t i) +{ + struct pyrf_branch_stack *pstack = (void *)obj; + struct pyrf_branch_entry *pentry; + + if (i < 0 || i >= (Py_ssize_t)pstack->nr) { + PyErr_SetString(PyExc_IndexError, "Index out of range"); + return NULL; + } + + pentry = PyObject_New(struct pyrf_branch_entry, &pyrf_branch_entry__type); + if (!pentry) + return NULL; + + pentry->from = pstack->entries[i].from; + pentry->to = pstack->entries[i].to; + pentry->flags = pstack->entries[i].flags; + + return (PyObject *)pentry; +} + +static PySequenceMethods pyrf_branch_stack__sequence_methods = { + .sq_length = pyrf_branch_stack__length, + .sq_item = pyrf_branch_stack__item, +}; + +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_as_sequence = &pyrf_branch_stack__sequence_methods, +}; + +static PyObject *pyrf_sample_event__get_brstack(PyObject *self, void *closure __maybe_unused) +{ + struct pyrf_event *pevent = (void *)self; + + if (!pevent->brstack) + Py_RETURN_NONE; + + Py_INCREF(pevent->brstack); + return pevent->brstack; +} + static PyObject* pyrf_sample_event__getattro(struct pyrf_event *pevent, PyObject *attr_name) { @@ -1012,6 +1163,12 @@ 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, @@ -1193,6 +1350,12 @@ 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; } @@ -1379,6 +1542,7 @@ static PyObject *pyrf_event__new(const union perf_event *event, struct evsel *ev perf_sample__init(&pevent->sample, /*all=*/true); pevent->callchain = NULL; + pevent->brstack = NULL; pevent->al_resolved = false; addr_location__init(&pevent->al); @@ -1436,6 +1600,27 @@ static PyObject *pyrf_event__new(const union perf_event *event, struct evsel *ev addr_location__exit(&al); } } + if (sample->branch_stack) { + struct branch_stack *bs = sample->branch_stack; + struct branch_entry *entries = perf_sample__branch_entries(sample); + struct pyrf_branch_stack *pstack; + + pstack = PyObject_New(struct pyrf_branch_stack, &pyrf_branch_stack__type); + if (!pstack) { + Py_DECREF(pevent); + return NULL; + } + pstack->nr = bs->nr; + pstack->entries = calloc(bs->nr, sizeof(struct branch_entry)); + if (!pstack->entries) { + Py_DECREF(pstack); + Py_DECREF(pevent); + return PyErr_NoMemory(); + } + memcpy(pstack->entries, entries, + bs->nr * sizeof(struct branch_entry)); + pevent->brstack = (PyObject *)pstack; + } return (PyObject *)pevent; } @@ -3988,6 +4173,18 @@ PyMODINIT_FUNC PyInit_perf(void) Py_INCREF(&pyrf_session__type); PyModule_AddObject(module, "session", (PyObject *)&pyrf_session__type); + Py_INCREF(&pyrf_branch_entry__type); + if (PyModule_AddObject(module, "branch_entry", (PyObject *)&pyrf_branch_entry__type) < 0) { + Py_DECREF(&pyrf_branch_entry__type); + goto error; + } + + Py_INCREF(&pyrf_branch_stack__type); + if (PyModule_AddObject(module, "branch_stack", (PyObject *)&pyrf_branch_stack__type) < 0) { + Py_DECREF(&pyrf_branch_stack__type); + goto error; + } + dict = PyModule_GetDict(module); if (dict == NULL) goto error; -- 2.54.0.1032.g2f8565e1d1-goog