kernel.git/tools/perf/util/python.c, branch linux-6.14.y

perf python: Check if there is space to copy all the event

2025-04-10T12:44:33Z

[ Upstream commit 89aaeaf84231157288035b366cb6300c1c6cac64 ] The pyrf_event__new() method copies the event obtained from the perf ring buffer to a structure that will then be turned into a python object for further consumption, so it copies perf_event.header.size bytes to its 'event' member: $ pahole -C pyrf_event /tmp/build/perf-tools-next/python/perf.cpython-312-x86_64-linux-gnu.so struct pyrf_event { PyObject ob_base; /* 0 16 */ struct evsel * evsel; /* 16 8 */ struct perf_sample sample; /* 24 312 */ /* XXX last struct has 7 bytes of padding, 2 holes */ /* --- cacheline 5 boundary (320 bytes) was 16 bytes ago --- */ union perf_event event; /* 336 4168 */ /* size: 4504, cachelines: 71, members: 4 */ /* member types with holes: 1, total: 2 */ /* paddings: 1, sum paddings: 7 */ /* last cacheline: 24 bytes */ }; $ It was doing so without checking if the event just obtained has more than that space, fix it. This isn't a proper, final solution, as we need to support larger events, but for the time being we at least bounds check and document it. Fixes: 877108e42b1b9ba6 ("perf tools: Initial python binding") Signed-off-by: Arnaldo Carvalho de Melo Reviewed-by: Ian Rogers Link: https://lore.kernel.org/r/20250312203141.285263-7-acme@kernel.org Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf python: Don't keep a raw_data pointer to consumed ring buffer space

2025-04-10T12:44:33Z

[ Upstream commit f3fed3ae34d606819d87a63d970cc3092a5be7ab ] When processing tracepoints the perf python binding was parsing the event before calling perf_mmap__consume(&md->core) in pyrf_evlist__read_on_cpu(). But part of this event parsing was to set the perf_sample->raw_data pointer to the payload of the event, which then could be overwritten by other event before tracepoint fields were asked for via event.prev_comm in a python program, for instance. This also happened with other fields, but strings were were problems were surfacing, as there is UTF-8 validation for the potentially garbled data. This ended up showing up as (with some added debugging messages): ( field 'prev_comm' ret=0x7f7c31f65110, raw_size=68 ) ( field 'prev_pid' ret=0x7f7c23b1bed0, raw_size=68 ) ( field 'prev_prio' ret=0x7f7c239c0030, raw_size=68 ) ( field 'prev_state' ret=0x7f7c239c0250, raw_size=68 ) time 14771421785867 prev_comm= prev_pid=1919907691 prev_prio=796026219 prev_state=0x303a32313175 ==> ( XXX '��' len=16, raw_size=68) ( field 'next_comm' ret=(nil), raw_size=68 ) Traceback (most recent call last): File "/home/acme/git/perf-tools-next/tools/perf/python/tracepoint.py", line 51, in main() File "/home/acme/git/perf-tools-next/tools/perf/python/tracepoint.py", line 46, in main event.next_comm, ^^^^^^^^^^^^^^^ AttributeError: 'perf.sample_event' object has no attribute 'next_comm' When event.next_comm was asked for, the PyUnicode_FromString() python API would fail and that tracepoint field wouldn't be available, stopping the tools/perf/python/tracepoint.py test tool. But, since we already do a copy of the whole event in pyrf_event__new, just use it and while at it remove what was done in in e8968e654191390a ("perf python: Fix pyrf_evlist__read_on_cpu event consuming") because we don't really need to wait for parsing the sample before declaring the event as consumed. This copy is questionable as is now, as it limits the maximum event + sample_type and tracepoint payload to sizeof(union perf_event), this all has been "working" because 'struct perf_event_mmap2', the largest entry in 'union perf_event' is: $ pahole -C perf_event ~/bin/perf | grep mmap2 struct perf_record_mmap2 mmap2; /* 0 4168 */ $ Fixes: bae57e3825a3dded ("perf python: Add support to resolve tracepoint fields") Signed-off-by: Arnaldo Carvalho de Melo Reviewed-by: Ian Rogers Link: https://lore.kernel.org/r/20250312203141.285263-6-acme@kernel.org Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf python: Decrement the refcount of just created event on failure

2025-04-10T12:44:33Z

[ Upstream commit 3de5a2bf5b4847f7a59a184568f969f8fe05d57f ] To avoid a leak if we have the python object but then something happens and we need to return the operation, decrement the offset of the newly created object. Fixes: 377f698db12150a1 ("perf python: Add struct evsel into struct pyrf_event") Signed-off-by: Arnaldo Carvalho de Melo Reviewed-by: Ian Rogers Link: https://lore.kernel.org/r/20250312203141.285263-5-acme@kernel.org Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf python: Fixup description of sample.id event member

2025-04-10T12:44:33Z

[ Upstream commit 1376c195e8ad327bb9f2d32e0acc5ac39e7cb30a ] Some old cut'n'paste error, its "ip", so the description should be "event ip", not "event type". Fixes: 877108e42b1b9ba6 ("perf tools: Initial python binding") Signed-off-by: Arnaldo Carvalho de Melo Reviewed-by: Ian Rogers Link: https://lore.kernel.org/r/20250312203141.285263-2-acme@kernel.org Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf python: Correctly throw IndexError

2024-12-18T19:24:33Z

Correctly throw IndexError for out-of-bound accesses to evlist: Python 3.11.9 (main, Jun 19 2024, 00:38:48) [GCC 13.2.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import sys >>> sys.path.insert(0, '/tmp/perf/python') >>> import perf >>> x=perf.parse_events('cycles') >>> print(x) evlist([cycles]) >>> x[2] Traceback (most recent call last): File "", line 1, in IndexError: Index out of range Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Colin Ian King Cc: Dapeng Mi Cc: Howard Chu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Kan Liang Cc: Mark Rutland Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Cc: Veronika Molnarova Cc: Weilin Wang Link: https://lore.kernel.org/r/20241119011644.971342-23-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf python: Add str and repr functions to evsel

2024-12-18T19:24:33Z

This allows evsel to be shown in the REPL like: Python 3.11.9 (main, Jun 19 2024, 00:38:48) [GCC 13.2.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import sys >>> sys.path.insert(0, '/tmp/perf/python') >>> import perf >>> x=perf.parse_events('cycles,data_read') >>> print(x) evlist([cycles,uncore_imc_free_running_0/data_read/,uncore_imc_free_running_1/data_read/]) >>> x[0] evsel(cycles) >>> x[1] evsel(uncore_imc_free_running_0/data_read/) >>> x[2] evsel(uncore_imc_free_running_1/data_read/) Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Colin Ian King Cc: Dapeng Mi Cc: Howard Chu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Kan Liang Cc: Mark Rutland Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Cc: Veronika Molnarova Cc: Weilin Wang Link: https://lore.kernel.org/r/20241119011644.971342-22-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf python: Add str and repr functions to evlist

2024-12-18T19:24:33Z

This allows the values in the evlist to be shown in the REPL like: Python 3.11.9 (main, Jun 19 2024, 00:38:48) [GCC 13.2.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import sys >>> sys.path.insert(0,'/tmp/perf/python') >>> import perf >>> perf.parse_events('cycles,data_read') evlist([cycles,uncore_imc_free_running_0/data_read/,uncore_imc_free_running_1/data_read/]) Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Colin Ian King Cc: Dapeng Mi Cc: Howard Chu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Kan Liang Cc: Mark Rutland Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Cc: Veronika Molnarova Cc: Weilin Wang Link: https://lore.kernel.org/r/20241119011644.971342-21-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf python: Add parse_events function

2024-12-18T19:24:33Z

Add basic parse_events function that takes a string and returns an evlist. As the python evlist is embedded in a pyrf_evlist, and the evsels are embedded in pyrf_evsels, copy the parsed data into those structs and update evsel__clone to enable this. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Colin Ian King Cc: Dapeng Mi Cc: Howard Chu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Kan Liang Cc: Mark Rutland Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Cc: Veronika Molnarova Cc: Weilin Wang Link: https://lore.kernel.org/r/20241119011644.971342-20-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf kwork: Make perf_kwork_add_work a callback

2024-12-18T19:24:33Z

perf_kwork_add_work is declared in builtin-kwork, whereas much kwork code is in util. To avoid needing to stub perf_kwork_add_work in python.c, add a callback to struct perf_kwork and initialize it in builtin-kwork to perf_kwork_add_work - this is the only struct perf_kwork. This removes the need for the stub in python.c. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Colin Ian King Cc: Dapeng Mi Cc: Howard Chu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Kan Liang Cc: Mark Rutland Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Cc: Veronika Molnarova Cc: Weilin Wang Link: https://lore.kernel.org/r/20241119011644.971342-18-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf bench: Remove reference to cmd_inject

2024-12-18T19:24:33Z

Avoid `perf bench internals inject-build-id` referencing the cmd_inject sub-command that requires perf-bench to backward reference internals of builtins. Replace the reference to cmd_inject with a call to main. To avoid python.c needing to link with something providing main, drop the libperf-bench library from the python shared object. Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Colin Ian King Cc: Dapeng Mi Cc: Howard Chu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Kan Liang Cc: Mark Rutland Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Cc: Veronika Molnarova Cc: Weilin Wang Link: https://lore.kernel.org/r/20241119011644.971342-17-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

kernel.git/tools/perf/util/python.c, branch linux-6.14.y

perf python: Check if there is space to copy all the event

perf python: Don't keep a raw_data pointer to consumed ring buffer space

perf python: Decrement the refcount of just created event on failure

perf python: Fixup description of sample.id event member

perf python: Correctly throw IndexError

perf python: Add __str__ and __repr__ functions to evsel

perf python: Add __str__ and __repr__ functions to evlist

perf python: Add parse_events function

perf kwork: Make perf_kwork_add_work a callback

perf bench: Remove reference to cmd_inject

perf python: Add str and repr functions to evsel

perf python: Add str and repr functions to evlist