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| author | Igor Lubashev <ilubashe@akamai.com> | 2019-08-07 10:44:14 -0400 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2019-08-14 10:48:39 -0300 |
| commit | c22e150e3afa6f8db2300bd510e4ac26bbee1bf3 (patch) | |
| tree | 62da5a7e092c75a43660d2075d626663d3aa3767 /tools/perf/util/event.h | |
| parent | 74d5f3d06f707eb5f7e1908ad88954bde02000ce (diff) | |
| download | linux-c22e150e3afa6f8db2300bd510e4ac26bbee1bf3.tar.bz2 | |
perf tools: Add helpers to use capabilities if present
Add utilities to help checking capabilities of the running procss. Make
perf link with libcap, if it is available. If no libcap-dev[el],
fallback to the geteuid() == 0 test used before.
Committer notes:
$ perf test python
18: 'import perf' in python : FAILED!
$ perf test -v python
Couldn't bump rlimit(MEMLOCK), failures may take place when creating BPF maps, etc
18: 'import perf' in python :
--- start ---
test child forked, pid 23288
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: /tmp/build/perf/python/perf.so: undefined symbol: cap_get_flag
test child finished with -1
---- end ----
'import perf' in python: FAILED!
$
This happens because differently from the perf binary generated with
this patch applied:
$ ldd /tmp/build/perf/perf | grep libcap
libcap.so.2 => /lib64/libcap.so.2 (0x00007f724a4ef000)
$
The python binding isn't linking with libcap:
$ ldd /tmp/build/perf/python/perf.so | grep libcap
$
So add 'cap' to the 'extra_libraries' variable in
tools/perf/util/setup.py, and rebuild:
$ perf test python
18: 'import perf' in python : Ok
$
If we explicitely disable libcap it also continues to work:
$ make NO_LIBCAP=1 -C tools/perf O=/tmp/build/perf install-bin
$ ldd /tmp/build/perf/perf | grep libcap
$ ldd /tmp/build/perf/python/perf.so | grep libcap
$ perf test python
18: 'import perf' in python : Ok
$
Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
[ split from a larger patch ]
Link: http://lkml.kernel.org/r/8a1e76cf5c7c9796d0d4d240fbaa85305298aafa.1565188228.git.ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/event.h')
| -rw-r--r-- | tools/perf/util/event.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h index 70841d115349..0e164e8ae28d 100644 --- a/tools/perf/util/event.h +++ b/tools/perf/util/event.h @@ -851,6 +851,7 @@ void cpu_map_data__synthesize(struct cpu_map_data *data, struct perf_cpu_map *m void event_attr_init(struct perf_event_attr *attr); int perf_event_paranoid(void); +bool perf_event_paranoid_check(int max_level); extern int sysctl_perf_event_max_stack; extern int sysctl_perf_event_max_contexts_per_stack; |