perf_counter: Introduce new (non-)paranoia level to allow raw tracepoint access

I want to sample inherited tracepoint workloads as a normal
user and the CAP_SYS_ADMIN check prevents me from doing that
right now.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar 2009-09-02 21:46:00 +02:00
parent f76bd108e5
commit 0fbdea19e9

View file

@ -46,12 +46,18 @@ static atomic_t nr_task_counters __read_mostly;
/*
* perf counter paranoia level:
* 0 - not paranoid
* 1 - disallow cpu counters to unpriv
* 2 - disallow kernel profiling to unpriv
* -1 - not paranoid at all
* 0 - disallow raw tracepoint access for unpriv
* 1 - disallow cpu counters for unpriv
* 2 - disallow kernel profiling for unpriv
*/
int sysctl_perf_counter_paranoid __read_mostly = 1;
static inline bool perf_paranoid_tracepoint_raw(void)
{
return sysctl_perf_counter_paranoid > -1;
}
static inline bool perf_paranoid_cpu(void)
{
return sysctl_perf_counter_paranoid > 0;
@ -3971,6 +3977,7 @@ static const struct pmu *tp_perf_counter_init(struct perf_counter *counter)
* have these.
*/
if ((counter->attr.sample_type & PERF_SAMPLE_RAW) &&
perf_paranoid_tracepoint_raw() &&
!capable(CAP_SYS_ADMIN))
return ERR_PTR(-EPERM);