Em Tue, Nov 08, 2016 at 04:11:00PM -0800, Andi Kleen escreveu: > From: Andi Kleen <a...@linux.intel.com> > > Since the unprivileged sched switch event was added in perf, > PT doesn't need need perf_event_paranoid=-1 anymore for > per cpu decoding. So remove the obsolete paragraph in > the documentation.
Thanks for pointing that out, I'll do something slightly different tho, pointing out that from kernel X.Y.Z, when the unprivileged PERF_RECORD_SWITCH metadata event was introduced, this is no longer an issue, having to be considered only on older kernels. - Arnaldo > Cc: adrian.hun...@intel.com > Signed-off-by: Andi Kleen <a...@linux.intel.com> > --- > tools/perf/Documentation/intel-pt.txt | 10 ---------- > 1 file changed, 10 deletions(-) > > diff --git a/tools/perf/Documentation/intel-pt.txt > b/tools/perf/Documentation/intel-pt.txt > index c6c8318e38a2..c7f817fd3611 100644 > --- a/tools/perf/Documentation/intel-pt.txt > +++ b/tools/perf/Documentation/intel-pt.txt > @@ -550,16 +550,6 @@ Unless /proc/sys/kernel/perf_event_paranoid is set to > -1, unprivileged users > have memory limits imposed upon them. That affects what buffer sizes they > can > have as outlined above. > > -Unless /proc/sys/kernel/perf_event_paranoid is set to -1, unprivileged users > are > -not permitted to use tracepoints which means there is insufficient side-band > -information to decode Intel PT in per-cpu mode, and potentially workload-only > -mode too if the workload creates new processes. > - > -Note also, that to use tracepoints, read-access to debugfs is required. So > if > -debugfs is not mounted or the user does not have read-access, it will again > not > -be possible to decode Intel PT in per-cpu mode. > - > - > sched_switch tracepoint > ----------------------- > > -- > 2.5.5
