From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dl1-f73.google.com (mail-dl1-f73.google.com [74.125.82.73]) (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 A431A38E5DC for ; Sat, 25 Apr 2026 22:50:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777157448; cv=none; b=gsPAD1l8NdhNo7cW4BBdD9SNr3dfwqi3D1OmFPQbQvw9Uw3iQvlzl0ZeBVliVlYLeqHv6UPbnl/RPIuarOZVAb1jC5oxKO6U/vU/is/Y64AaY7ZNBG5lMd3M0uRHk5Kqyov94YZaWnu25Qip+JVZrimJysf/FXdemFPNJJTaXDs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777157448; c=relaxed/simple; bh=ozNykEEtUHxpduvqP4J+aLXrCBbkFXDFkwW7iCbRseM=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=J4cmIEF4lTFqMXg5WWC9NGd3lg8X5I4ZO7VqQ3OaB9QvrxWSp+LDBnwdXXLb8c7OdmxXZw/iDXuI2vOB7zyt+aRa8w/Tn+ccpr2WxDZBbnkuhV6KL+rC4fPhVLBk2JEc+IMcI2hZw4UvkNfMemKFV73q80jn2nHSo8TTZ5X6lgM= 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=irp6lS/D; arc=none smtp.client-ip=74.125.82.73 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="irp6lS/D" Received: by mail-dl1-f73.google.com with SMTP id a92af1059eb24-12c726f4055so9219189c88.1 for ; Sat, 25 Apr 2026 15:50:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1777157445; x=1777762245; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:from:to:cc:subject:date:message-id :reply-to; bh=ksoru2Zcnv41fS9ZZdiwot6rjc0ud5JoTNQnJ6ZzGMs=; b=irp6lS/Drvv6ic6ohD+/Qt6acD8ohWtZr4LepISYJbzXI05RaXFdtevie4s3ksGNiy ww8kZv14mTByHTUS61XICB3wsiSt4W6lSYrwn2+ByklffWnSQnjDKLuKcygCaJl3Wfq1 xuXO/8bfuiDWyeCgony0q0Yv5eQOKE8PuhI9yiQpQmm8h8nGZTUDwT2JX8pwDF89LD9D MBM4ofE2z1s0nOspskJxy8j0Vl8wUktST6RYieCtpOoAF1S3DN6i1K4zWZiDhzkUJKCM qZlMZDkUaMrEfWLejQPksNQiIhS+GOJxM+MSgs94kzippfnu5jpUoRpT/bSJakf1axdg TEiA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777157445; x=1777762245; h=content-transfer-encoding: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=ksoru2Zcnv41fS9ZZdiwot6rjc0ud5JoTNQnJ6ZzGMs=; b=Jea+jIRqufH/YfiUdo/Eizk+vcgEoUV02IUv39ifjfwJbMpHr6bi1WD2ISNaACfAMD fdBUKxgRc6Y5kpMxmN9idfYTGqYU/BxJ/Jsg2t6647iQKjd5A3HixhkWFq+3lZ/xq9du E+mmrpHMUrouo1TTrLdclzzqlrwpSrh7VE0R5yZ5a3yUdha30Pw1NF9MORXCTKwAylBz 9RAJfJLDB2e0ZpLdSu3J3rdnkyDB8piEPvPF86kBSthTE4WsPiflLP+ga4I557GMweVE bbD7w7+JqIUNTRuw6za7EQZUXx9CHUFADpdVv2Zf6OZshE6x7O8YZiR67OeI/CaEfKOo GMVQ== X-Forwarded-Encrypted: i=1; AFNElJ9eQuyzvzG+mkRFR5u5sd+SrZbtg/aNtA+3cagi2z7Dkx8Ba1ooSN3uM7OzfLbG8fqixSft7K7aMZRrqTMSK+Qr@vger.kernel.org X-Gm-Message-State: AOJu0Yz4+DVDyh65HBHMz4grGISqyeeKV4Easx6ImfoWnIOzYZNH9qgH PAqftxSBW0iRtGx8O28NW3QkhgEr7RBfo+ReVsDkQJnDseI8ntP5VLYrG9Tng10Il/v15mCUbF0 hqqgCmwcThw== X-Received: from dlad14.prod.google.com ([2002:a05:701b:220e:b0:12c:1ff3:9fa4]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:220f:b0:127:5cd6:fa45 with SMTP id a92af1059eb24-12c73f72632mr18303113c88.14.1777157444626; Sat, 25 Apr 2026 15:50:44 -0700 (PDT) Date: Sat, 25 Apr 2026 15:49:07 -0700 In-Reply-To: <20260425224951.174663-1-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: <20260425174858.3922152-1-irogers@google.com> <20260425224951.174663-1-irogers@google.com> X-Mailer: git-send-email 2.54.0.545.g6539524ca2-goog Message-ID: <20260425224951.174663-16-irogers@google.com> Subject: [PATCH v7 15/59] perf python: Add python session abstraction wrapping perf's session From: Ian Rogers To: acme@kernel.org, adrian.hunter@intel.com, james.clark@linaro.org, leo.yan@linux.dev, namhyung@kernel.org, tmricht@linux.ibm.com Cc: alice.mei.rogers@gmail.com, dapeng1.mi@linux.intel.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, Ian Rogers Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sessions are necessary to be able to use perf.data files within a tool. Add a wrapper python type that incorporates the tool. Allow a sample callback to be passed when creating the session. When process_events is run this callback will be called, if supplied, for sample events. An example use looks like: ``` $ perf record -e cycles,instructions -a sleep 3 $ PYTHONPATH=3D..../perf/python python3 Python 3.13.7 (main, Aug 20 2025, 22:17:40) [GCC 14.2.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import perf >>> count=3D0 ... def handle_sample(x): ... global count ... if count < 3: ... print(dir(x)) ... count =3D count + 1 ... perf.session(perf.data("perf.data"),sample=3Dhandle_sample).process_eve= nts() ... ['__class__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', = '__ge__', '__getattribute__', '__getstate__', '__gt__', '__hash__', '__init= __', '__init_subclass__', '__le__', '__lt__', '__ne__', '__new__', '__reduc= e__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', = '__subclasshook__', 'sample_addr', 'sample_cpu', 'sample_id', 'sample_ip', = 'sample_period', 'sample_pid', 'sample_stream_id', 'sample_tid', 'sample_ti= me', 'type'] ['__class__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', = '__ge__', '__getattribute__', '__getstate__', '__gt__', '__hash__', '__init= __', '__init_subclass__', '__le__', '__lt__', '__ne__', '__new__', '__reduc= e__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', = '__subclasshook__', 'sample_addr', 'sample_cpu', 'sample_id', 'sample_ip', = 'sample_period', 'sample_pid', 'sample_stream_id', 'sample_tid', 'sample_ti= me', 'type'] ['__class__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', = '__ge__', '__getattribute__', '__getstate__', '__gt__', '__hash__', '__init= __', '__init_subclass__', '__le__', '__lt__', '__ne__', '__new__', '__reduc= e__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', = '__subclasshook__', 'sample_addr', 'sample_cpu', 'sample_id', 'sample_ip', = 'sample_period', 'sample_pid', 'sample_stream_id', 'sample_tid', 'sample_ti= me', 'type'] ``` Also, add the ability to get the thread associated with a session. For threads, allow the comm string to be retrieved. This can be useful for filtering threads. Connect up some of the standard event handling in psession->tool to better support queries of the machine. Also connect up the symbols. Assisted-by: Gemini:gemini-3.1-pro-preview Signed-off-by: Ian Rogers --- v2: 1. Fixed Potential Crash in pyrf_thread__comm : Used thread__comm_str() to safely retrieve the command name, avoiding a crash if thread__comm() returns NULL. 2. Fixed Double Free Risk: Zeroed out user_regs , intr_regs , and callchain in the shallow copy of perf_sample to prevent Python from attempting to free pointers it doesn't own. 3. Fixed Memory Leak & Exception Handling in Callback: Handled the return value of PyObject_CallFunction() to avoid leaks, and checked for failure to abort the loop and propagate Python exceptions cleanly. 4. Enforced Type Safety: Used O! with &pyrf_data__type in PyArg_ParseTupleAndKeywords to prevent bad casts from passing arbitrary objects as perf.data. 5. Added Missing Build ID Handler: Registered perf_event__process_build_id to allow correct symbol resolution. 6. Fixed Double Free Crash on Init Failure: Set session and pdata to NULL on failure to prevent tp_dealloc from double-freeing them. 7. Preserved C-level Errors: Made pyrf_session__process_events return the error code integer rather than always returning None . --- v7: - Fixed NULL comm handling. - Avoided swallowing exceptions in module init. - Fixed checkpatch warning for missing blank line. --- tools/perf/util/python.c | 279 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 273 insertions(+), 6 deletions(-) diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c index aa63c7ffe822..1af53480661f 100644 --- a/tools/perf/util/python.c +++ b/tools/perf/util/python.c @@ -9,8 +9,10 @@ #include =20 #include "callchain.h" +#include "comm.h" #include "counts.h" #include "data.h" +#include "debug.h" #include "event.h" #include "evlist.h" #include "evsel.h" @@ -20,8 +22,12 @@ #include "pmus.h" #include "print_binary.h" #include "record.h" +#include "session.h" #include "strbuf.h" +#include "symbol.h" +#include "thread.h" #include "thread_map.h" +#include "tool.h" #include "tp_pmu.h" #include "trace-event.h" #include "util/sample.h" @@ -2413,6 +2419,256 @@ static int pyrf_data__setup_types(void) return PyType_Ready(&pyrf_data__type); } =20 +struct pyrf_thread { + PyObject_HEAD + + struct thread *thread; +}; + +static void pyrf_thread__delete(struct pyrf_thread *pthread) +{ + thread__put(pthread->thread); + Py_TYPE(pthread)->tp_free((PyObject *)pthread); +} + +static PyObject *pyrf_thread__comm(PyObject *obj) +{ + struct pyrf_thread *pthread =3D (void *)obj; + const char *str =3D thread__comm_str(pthread->thread); + + if (!str) + Py_RETURN_NONE; + + return PyUnicode_FromString(str); +} + +static PyMethodDef pyrf_thread__methods[] =3D { + { + .ml_name =3D "comm", + .ml_meth =3D (PyCFunction)pyrf_thread__comm, + .ml_flags =3D METH_NOARGS, + .ml_doc =3D PyDoc_STR("Comm(and) associated with this thread.") + }, + { .ml_name =3D NULL, } +}; + +static const char pyrf_thread__doc[] =3D PyDoc_STR("perf thread object."); + +static PyTypeObject pyrf_thread__type =3D { + PyVarObject_HEAD_INIT(NULL, 0) + .tp_name =3D "perf.thread", + .tp_basicsize =3D sizeof(struct pyrf_thread), + .tp_dealloc =3D (destructor)pyrf_thread__delete, + .tp_flags =3D Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE, + .tp_methods =3D pyrf_thread__methods, + .tp_doc =3D pyrf_thread__doc, +}; + +static int pyrf_thread__setup_types(void) +{ + return PyType_Ready(&pyrf_thread__type); +} + +static PyObject *pyrf_thread__from_thread(struct thread *thread) +{ + struct pyrf_thread *pthread =3D PyObject_New(struct pyrf_thread, &pyrf_th= read__type); + + if (!pthread) + return NULL; + + pthread->thread =3D thread__get(thread); + return (PyObject *)pthread; +} + +struct pyrf_session { + PyObject_HEAD + + struct perf_session *session; + struct perf_tool tool; + struct pyrf_data *pdata; + PyObject *sample; + PyObject *stat; +}; + +static int pyrf_session_tool__sample(const struct perf_tool *tool, + union perf_event *event, + struct perf_sample *sample, + struct evsel *evsel, + struct machine *machine __maybe_unused) +{ + struct pyrf_session *psession =3D container_of(tool, struct pyrf_session,= tool); + PyObject *pyevent =3D pyrf_event__new(event); + struct pyrf_event *pevent =3D (struct pyrf_event *)pyevent; + PyObject *ret; + + if (pyevent =3D=3D NULL) + return -ENOMEM; + + memcpy(&pevent->event, event, event->header.size); + if (evsel__parse_sample(evsel, &pevent->event, &pevent->sample) < 0) { + Py_DECREF(pyevent); + return -1; + } + /* Avoid shallow copy pointing to lazily allocated memory that would be d= ouble freed. */ + pevent->sample.user_regs =3D NULL; + pevent->sample.intr_regs =3D NULL; + if (pevent->sample.merged_callchain) + pevent->sample.callchain =3D NULL; + + ret =3D PyObject_CallFunction(psession->sample, "O", pyevent); + if (!ret) { + PyErr_Print(); + Py_DECREF(pyevent); + return -1; + } + Py_DECREF(ret); + Py_DECREF(pyevent); + return 0; +} + +static PyObject *pyrf_session__find_thread(struct pyrf_session *psession, = PyObject *args) +{ + struct machine *machine; + struct thread *thread =3D NULL; + PyObject *result; + int pid; + + if (!PyArg_ParseTuple(args, "i", &pid)) + return NULL; + + machine =3D &psession->session->machines.host; + thread =3D machine__find_thread(machine, pid, pid); + + if (!thread) { + machine =3D perf_session__find_machine(psession->session, pid); + if (machine) + thread =3D machine__find_thread(machine, pid, pid); + } + + if (!thread) { + PyErr_Format(PyExc_TypeError, "Failed to find thread %d", pid); + return NULL; + } + result =3D pyrf_thread__from_thread(thread); + thread__put(thread); + return result; +} + +static int pyrf_session__init(struct pyrf_session *psession, PyObject *arg= s, PyObject *kwargs) +{ + struct pyrf_data *pdata; + PyObject *sample =3D NULL; + static char *kwlist[] =3D { "data", "sample", NULL }; + + if (!PyArg_ParseTupleAndKeywords(args, kwargs, "O!|O", kwlist, &pyrf_data= __type, &pdata, + &sample)) + return -1; + + Py_INCREF(pdata); + psession->pdata =3D pdata; + perf_tool__init(&psession->tool, /*ordered_events=3D*/true); + psession->tool.ordering_requires_timestamps =3D true; + + #define ADD_TOOL(name) \ + do { \ + if (name) { \ + if (!PyCallable_Check(name)) { \ + PyErr_SetString(PyExc_TypeError, #name " must be callable"); \ + return -1; \ + } \ + psession->tool.name =3D pyrf_session_tool__##name; \ + Py_INCREF(name); \ + psession->name =3D name; \ + } \ + } while (0) + + ADD_TOOL(sample); + #undef ADD_TOOL + + psession->tool.comm =3D perf_event__process_comm; + psession->tool.mmap =3D perf_event__process_mmap; + psession->tool.mmap2 =3D perf_event__process_mmap2; + psession->tool.namespaces =3D perf_event__process_namespaces; + psession->tool.cgroup =3D perf_event__process_cgroup; + psession->tool.exit =3D perf_event__process_exit; + psession->tool.fork =3D perf_event__process_fork; + psession->tool.ksymbol =3D perf_event__process_ksymbol; + psession->tool.text_poke =3D perf_event__process_text_poke; + psession->tool.build_id =3D perf_event__process_build_id; + psession->session =3D perf_session__new(&pdata->data, &psession->tool); + if (IS_ERR(psession->session)) { + PyErr_Format(PyExc_IOError, "failed to create session: %ld", + PTR_ERR(psession->session)); + psession->session =3D NULL; + Py_DECREF(pdata); + psession->pdata =3D NULL; + return -1; + } + + if (symbol__init(perf_session__env(psession->session)) < 0) { + perf_session__delete(psession->session); + psession->session =3D NULL; + Py_DECREF(psession->pdata); + psession->pdata =3D NULL; + return -1; + } + + if (perf_session__create_kernel_maps(psession->session) < 0) + pr_warning("Cannot read kernel map\n"); + + return 0; +} + +static void pyrf_session__delete(struct pyrf_session *psession) +{ + Py_XDECREF(psession->pdata); + Py_XDECREF(psession->sample); + perf_session__delete(psession->session); + Py_TYPE(psession)->tp_free((PyObject *)psession); +} + +static PyObject *pyrf_session__find_thread_events(struct pyrf_session *pse= ssion) +{ + int err =3D perf_session__process_events(psession->session); + + return PyLong_FromLong(err); +} + +static PyMethodDef pyrf_session__methods[] =3D { + { + .ml_name =3D "process_events", + .ml_meth =3D (PyCFunction)pyrf_session__find_thread_events, + .ml_flags =3D METH_NOARGS, + .ml_doc =3D PyDoc_STR("Iterate and process events.") + }, + { + .ml_name =3D "find_thread", + .ml_meth =3D (PyCFunction)pyrf_session__find_thread, + .ml_flags =3D METH_VARARGS, + .ml_doc =3D PyDoc_STR("Returns the thread associated with a pid.") + }, + { .ml_name =3D NULL, } +}; + +static const char pyrf_session__doc[] =3D PyDoc_STR("perf session object."= ); + +static PyTypeObject pyrf_session__type =3D { + PyVarObject_HEAD_INIT(NULL, 0) + .tp_name =3D "perf.session", + .tp_basicsize =3D sizeof(struct pyrf_session), + .tp_dealloc =3D (destructor)pyrf_session__delete, + .tp_flags =3D Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE, + .tp_methods =3D pyrf_session__methods, + .tp_doc =3D pyrf_session__doc, + .tp_init =3D (initproc)pyrf_session__init, +}; + +static int pyrf_session__setup_types(void) +{ + pyrf_session__type.tp_new =3D PyType_GenericNew; + return PyType_Ready(&pyrf_session__type); +} + static PyMethodDef perf__methods[] =3D { { .ml_name =3D "metrics", @@ -2467,8 +2723,10 @@ PyMODINIT_FUNC PyInit_perf(void) }; PyObject *module =3D PyModule_Create(&moduledef); =20 - if (module =3D=3D NULL || - pyrf_event__setup_types() < 0 || + if (module =3D=3D NULL) + return NULL; + + if (pyrf_event__setup_types() < 0 || pyrf_evlist__setup_types() < 0 || pyrf_evsel__setup_types() < 0 || pyrf_thread_map__setup_types() < 0 || @@ -2476,8 +2734,12 @@ PyMODINIT_FUNC PyInit_perf(void) pyrf_pmu_iterator__setup_types() < 0 || pyrf_pmu__setup_types() < 0 || pyrf_counts_values__setup_types() < 0 || - pyrf_data__setup_types() < 0) - return module; + pyrf_data__setup_types() < 0 || + pyrf_session__setup_types() < 0 || + pyrf_thread__setup_types() < 0) { + Py_DECREF(module); + return NULL; + } =20 /* The page_size is placed in util object. */ page_size =3D sysconf(_SC_PAGE_SIZE); @@ -2527,6 +2789,9 @@ PyMODINIT_FUNC PyInit_perf(void) Py_INCREF(&pyrf_data__type); PyModule_AddObject(module, "data", (PyObject *)&pyrf_data__type); =20 + Py_INCREF(&pyrf_session__type); + PyModule_AddObject(module, "session", (PyObject *)&pyrf_session__type); + dict =3D PyModule_GetDict(module); if (dict =3D=3D NULL) goto error; @@ -2540,7 +2805,9 @@ PyMODINIT_FUNC PyInit_perf(void) } =20 error: - if (PyErr_Occurred()) - PyErr_SetString(PyExc_ImportError, "perf: Init failed!"); + if (PyErr_Occurred()) { + Py_XDECREF(module); + return NULL; + } return module; } --=20 2.54.0.545.g6539524ca2-goog