4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit cc437642255224e4140fed1f3e3156fc8ad91903 ]
In Python3, the result of PyModule_Create (called from scripts/python/Perf-Trace-Util/Context.c) is not automatically added to sys.modules. See: https://bugs.python.org/issue4592
Below is the observed behavior without the fix:
# ldd /usr/bin/perf | grep -i python libpython3.6m.so.1.0 => /usr/lib64/libpython3.6m.so.1.0 (0x00007f8e1dfb2000)
# perf record /bin/false [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.015 MB perf.data (17 samples) ]
# perf script -g python | cat generated Python script: perf-script.py
# perf script -s ./perf-script.py Traceback (most recent call last): File "./perf-script.py", line 18, in <module> from perf_trace_context import * ModuleNotFoundError: No module named 'perf_trace_context' Error running python script ./perf-script.py #
Committer notes:
To build with python3 use:
$ make -C tools/perf PYTHON=python3
Use a non-const variable to pass the 'name' arg to PyImport_AppendInittab(), as python2.6 has that as 'char *', which ends up trowing this in some environments:
CC /tmp/build/perf/util/parse-branch-options.o util/scripting-engines/trace-event-python.c: In function 'python_start_script': util/scripting-engines/trace-event-python.c:1520:2: error: passing argument 1 of 'PyImport_AppendInittab' discards 'const' qualifier from pointer target type [-Werror] PyImport_AppendInittab("perf_trace_context", initfunc); ^ In file included from /usr/include/python2.6/Python.h:130:0, from util/scripting-engines/trace-event-python.c:22: /usr/include/python2.6/import.h:54:17: note: expected 'char *' but argument is of type 'const char *' PyAPI_FUNC(int) PyImport_AppendInittab(char *name, void (*initfunc)(void)); ^ cc1: all warnings being treated as errors
Signed-off-by: Tony Jones tonyj@suse.de Acked-by: Jiri Olsa jolsa@kernel.org Tested-by: Arnaldo Carvalho de Melo acme@redhat.com Cc: Jaroslav Škarvada jskarvad@redhat.com Cc: Jonathan Corbet corbet@lwn.net Cc: Ravi Bangoria ravi.bangoria@linux.ibm.com Cc: Seeteena Thoufeek s1seetee@linux.vnet.ibm.com Fixes: 66dfdff03d19 ("perf tools: Add Python 3 support") Link: http://lkml.kernel.org/r/20190124005229.16146-2-tonyj@suse.de Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../perf/util/scripting-engines/trace-event-python.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c index fb11396ec861..9569cc06e0a7 100644 --- a/tools/perf/util/scripting-engines/trace-event-python.c +++ b/tools/perf/util/scripting-engines/trace-event-python.c @@ -1493,34 +1493,40 @@ static void _free_command_line(wchar_t **command_line, int num) static int python_start_script(const char *script, int argc, const char **argv) { struct tables *tables = &tables_global; + PyMODINIT_FUNC (*initfunc)(void); #if PY_MAJOR_VERSION < 3 const char **command_line; #else wchar_t **command_line; #endif - char buf[PATH_MAX]; + /* + * Use a non-const name variable to cope with python 2.6's + * PyImport_AppendInittab prototype + */ + char buf[PATH_MAX], name[19] = "perf_trace_context"; int i, err = 0; FILE *fp;
#if PY_MAJOR_VERSION < 3 + initfunc = initperf_trace_context; command_line = malloc((argc + 1) * sizeof(const char *)); command_line[0] = script; for (i = 1; i < argc + 1; i++) command_line[i] = argv[i - 1]; #else + initfunc = PyInit_perf_trace_context; command_line = malloc((argc + 1) * sizeof(wchar_t *)); command_line[0] = Py_DecodeLocale(script, NULL); for (i = 1; i < argc + 1; i++) command_line[i] = Py_DecodeLocale(argv[i - 1], NULL); #endif
+ PyImport_AppendInittab(name, initfunc); Py_Initialize();
#if PY_MAJOR_VERSION < 3 - initperf_trace_context(); PySys_SetArgv(argc + 1, (char **)command_line); #else - PyInit_perf_trace_context(); PySys_SetArgv(argc + 1, command_line); #endif