On Wed, 19 Feb 2014, Martin Ichilevici de Oliveira wrote: > Manu, > > Thank you very much for the reference and code. I checked my cpu and > the Northbridge performance counter flag is set. So my processor does > support profiling NB events. The question now is why it's saying it's > not. > > I realized that perf support for NB events was in fact only added on > linux 3.9 [1], so I upgraded both my kernel and perf to 3.11. So > that's out.
The support for AMD fam15h northbridge events was introduced in 3.9, but the perf interface for it was changed in an incompatible way in 3.10. To access the counters starting in 3.10 they are in a separate PMU. You need to be root and you need to set the type field to the proper PMU. You might be better off using something like libpfm4 to find out what aw values to use, trying to set them by hand is a hassle. Vince -- To unsubscribe from this list: send the line "unsubscribe linux-perf-users" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
