Re: What perf_event_paranoid can do?
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On Mon, Mar 21, 2011 at 2:14 PM, 陳韋任 <chenwj@xxxxxxxxxxxxxxxxx> wrote: > Hi, folks > > I don't know what "perf_event_paranoid" is for. Sometimes > `perf` told me tweaking perf_event_paranoid. For example, > > $ perf stat -e branches:pp ls > No permission to collect stats. > Consider tweaking /proc/sys/kernel/perf_event_paranoid. > > I cannot find any document talks about what perf_event_paranoid > is and what we can do on it. It's used to control if some action is allowed or not for normal user. See comments at kernel/perf_event.c: /* * perf event paranoia level: * -1 - not paranoid at all * 0 - disallow raw tracepoint access for unpriv * 1 - disallow cpu events for unpriv * 2 - disallow kernel profiling for unpriv */ Lin Ming > > Any suggestion appreciated. > > Regards, > chenwj > > -- > Wei-Ren Chen (陳韋任) > Parallel Processing Lab, Institute of Information Science, > Academia Sinica, Taiwan (R.O.C.) > Tel:886-2-2788-3799 #1667 > -- > To unsubscribe from this list: send the line "unsubscribe linux-perf-users" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-perf-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html