Re: [QUERY] Why does perf-trace need me to be root?

From: Ingo Molnar
Date: Thu Oct 03 2013 - 02:25:16 EST



* Ramkumar Ramachandra <artagnon@xxxxxxxxx> wrote:

> David Ahern wrote:
> > If you trust your users make the debugfs mount point rx by group,world.
>
> Thanks David. I can preserve this configuration across reboots by
> putting an entry in fstab, right? How do I preserve the value of
> /proc/sys/kernel/perf_event_paranoid across reboots?

via:

echo 'kernel.perf_event_paranoid = -1' >> /etc/sysctl.conf

I think 'perf trace' should probably print such suggestions when it
notices a privilege problem, to make it far more obvious for new users to
correctly configure their system for easy tracing.

The current output:

comet:~/tip> perf trace
Couldn't read the raw_syscalls tracepoints information!

is as hostile to the user as it gets ;-)

Thanks,

Ingo
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