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 820B63D8137 for ; Tue, 28 Apr 2026 07:19:57 +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=1777360799; cv=none; b=cBQ5Mh2/0L9nCWUGkulkPF/MoqDxTyptouzEU+hzuc2K4PcHdX+rSTdw/Nxam939/W+2nnIDJ62oGvr+Q9z8iJxz+XKe+YlDcbAaKw1U3pxOStkSwZN3qOw9fKc7GCy2z38I0bhTeWYP6UBJHYBK7vpqtrGrTPOvG4he3vL5dyM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777360799; c=relaxed/simple; bh=sHlykUY8ugsPXc0OzhhBnJwhekD8IQ6BM2q1Ln/DcUM=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=U16uvb6IzuanBkGiN/SZnvDzL0WLF92yFnYoxoa5Rgd5S7l//sgbkEX/Rrrmfjk3we8s85PsLb5XfyLSo8v8xtaL2X2vrZ2fl/pocGE9XMpSjzO5z3PUqi8i6VmQ4EUYagIn6Mkn9JCGrfrhVel11y5GRLGYMKOFhvmXBJx6wNw= 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=Oz0IodND; 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="Oz0IodND" Received: by mail-dy1-f201.google.com with SMTP id 5a478bee46e88-2c16233ee11so15294738eec.1 for ; Tue, 28 Apr 2026 00:19:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1777360797; x=1777965597; 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=NM8MmFs51bCluxfEvZVq8FmIxeuvBEx0XSUWwcZ6XFQ=; b=Oz0IodNDn6++a7yU1ppyZ8z9izRIldRngufuId1xywsLgbaEoy2xM7uvy0QVwALyrR L3NR7W9wG/d2onYS6PHTFokPeqTUVHLkjwjHOig4ma5zt7vWMnPatUfrMyWRSM3FoLLs CuPrJC7N7gOAXUstAiZK+l7igIi9OYExDZkRDkEd8oIGGdOMIrbIjpxYm5TkVqzG+dxX sBWlM6iFzYO2x+m0p+yG1BYA6e7hL+8Hf6/sDm7gIRIOmC+M1TlVY0V69sBgdt7/PCJ3 ycfsPMtbu0nRv/3HOSy9cvf7BdO88kltBh7aBnOKEq0G54UG03v+4qZPd8tDwJVrDtWs GIPQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777360797; x=1777965597; 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=NM8MmFs51bCluxfEvZVq8FmIxeuvBEx0XSUWwcZ6XFQ=; b=sucvXaPMxJpQSuApe9nHlQn+jd4VYCWNhkMsXkx0RArrh+R5oqCthvfP1nfJ5Su6PR jx+X4CbChkW7drNUqgdZoR2x9wqS++BC9m/ueWuqsiQQOfOe0bBDTNlDdKC3d9SmGSrr YjWqAyk9zQvsJgIuXBhQrIkoKglO5XmipHdpEg0aTqYPHo9I7MSbi+0mSXyMVwwZCJql RdC3plPsG+LW6qnrLjrayPSZIzn+0Yl6w5qVaIQLx1MFMu4fDCy0oWwZNp9n+kkx5vGl JSSQpNuHHCRBUnbkYhs2bVQdEi/hv36JLGTvLbUTz76mLqMm5mvrhcMMsw/zqXylaAWy E2Pw== X-Forwarded-Encrypted: i=1; AFNElJ+W0ea+l5hHHzJZRasqfcgC7d7xQ07yONarg2SEUcx0JirVwRhE+x4xNalsJ0C2BdSEiyuMQo7oTDFOlbUYwC6O@vger.kernel.org X-Gm-Message-State: AOJu0YzepxSufOsaA6EzcB7fq1dp6HgD2xu36k+FzoBLiVpTQYzOdj6+ d05XvoTFk0A7k+nhNYxhhtQ/6mCn2qwFE4YK8lJtnlbks4Y4KiNviQq6rhutupbflDofYw42S1x /rj8t82tfgw== X-Received: from dybqo1.prod.google.com ([2002:a05:7301:6781:b0:2d8:c995:cafe]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7300:6412:b0:2ed:e12:376a with SMTP id 5a478bee46e88-2ed0e128922mr513997eec.32.1777360796315; Tue, 28 Apr 2026 00:19:56 -0700 (PDT) Date: Tue, 28 Apr 2026 00:18:24 -0700 In-Reply-To: <20260428071903.1886173-1-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: <20260425224951.174663-1-irogers@google.com> <20260428071903.1886173-1-irogers@google.com> X-Mailer: git-send-email 2.54.0.545.g6539524ca2-goog Message-ID: <20260428071903.1886173-20-irogers@google.com> Subject: [PATCH v8 19/58] perf python: Expose brstack in sample event From: Ian Rogers To: 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-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, tmricht@linux.ibm.com, Ian Rogers 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 | 188 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 188 insertions(+) diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c index 144fbc85fcb3..c947abf8affe 100644 --- a/tools/perf/util/python.c +++ b/tools/perf/util/python.c @@ -17,6 +17,7 @@ #include "debug.h" #include "dso.h" #include "event.h" +#include "branch.h" #include "evlist.h" #include "evsel.h" #include "expr.h" @@ -66,6 +67,8 @@ 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; }; @@ -104,6 +107,7 @@ 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); } @@ -916,6 +920,144 @@ 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 pyrf_event *pevent; + struct branch_entry *entries; + u64 nr; + u64 pos; +}; + +static void pyrf_branch_stack__delete(struct pyrf_branch_stack *pstack) +{ + Py_XDECREF(pstack->pevent); + free(pstack->entries); + Py_TYPE(pstack)->tp_free((PyObject *)pstack); +} + +static PyObject *pyrf_branch_stack__next(struct pyrf_branch_stack *pstack) +{ + struct pyrf_branch_entry *pentry; + + if (pstack->pos >= pstack->nr) + return NULL; + + pentry = PyObject_New(struct pyrf_branch_entry, &pyrf_branch_entry__type); + if (!pentry) + return NULL; + + pentry->from = pstack->entries[pstack->pos].from; + pentry->to = pstack->entries[pstack->pos].to; + pentry->flags = pstack->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; + + 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) { @@ -936,6 +1078,12 @@ 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, @@ -1117,6 +1265,12 @@ 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; } @@ -1303,6 +1457,7 @@ 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); @@ -1359,6 +1514,27 @@ 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_INCREF(pevent); + pstack->pevent = pevent; + pstack->pos = 0; + pstack->nr = bs->nr; + pstack->entries = calloc(bs->nr, sizeof(struct branch_entry)); + if (pstack->entries) { + memcpy(pstack->entries, entries, + bs->nr * sizeof(struct branch_entry)); + pevent->brstack = (PyObject *)pstack; + } else { + Py_DECREF(pstack); + } + } + } return (PyObject *)pevent; } @@ -3735,6 +3911,18 @@ 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; -- 2.54.0.545.g6539524ca2-goog