mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 16:29:59 +00:00
c22e150e3a
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>
29 lines
468 B
C
29 lines
468 B
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Capability utilities
|
|
*/
|
|
|
|
#ifdef HAVE_LIBCAP_SUPPORT
|
|
|
|
#include "cap.h"
|
|
#include <stdbool.h>
|
|
#include <sys/capability.h>
|
|
|
|
bool perf_cap__capable(cap_value_t cap)
|
|
{
|
|
cap_flag_value_t val;
|
|
cap_t caps = cap_get_proc();
|
|
|
|
if (!caps)
|
|
return false;
|
|
|
|
if (cap_get_flag(caps, cap, CAP_EFFECTIVE, &val) != 0)
|
|
val = CAP_CLEAR;
|
|
|
|
if (cap_free(caps) != 0)
|
|
return false;
|
|
|
|
return val == CAP_SET;
|
|
}
|
|
|
|
#endif /* HAVE_LIBCAP_SUPPORT */
|