Messages in this thread | | | Date | Tue, 24 May 2011 14:57:22 -0600 | From | David Ahern <> | Subject | Re: perf: regression -- missing /sys/devices/system/cpu/perf_events |
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On 05/24/11 14:12, Vince Weaver wrote: > On Tue, 24 May 2011, Ingo Molnar wrote: >> >> So, what is wrong with the method Peter suggested: the presence of the perf >> syscall (it not returning -ENOSYS) is bona fide evidence that perf is >> available. > > it's just hard to do that from a shell script.
What about kallsyms:
grep sys_perf_event_open /proc/kallsyms
even with the new security feature you should be able to see that it exists. The name has been the same since the counters->events rename in cdd6c48. egrep for both names for kernels older than 2.6.31.
David
> > also, running the perf syscall can be tricky if you have a new kernel but > an older set of header files that doesn't have the syscall number defined. > > Vince > vweaver1@eecs.utk.edu > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
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