Messages in this thread | | | Date | Fri, 17 May 2013 11:04:51 +0200 | From | Peter Zijlstra <> | Subject | Re: Drop WARN on AMD lack of perfctrs |
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On Thu, May 16, 2013 at 11:34:20PM +0200, Borislav Petkov wrote: > On Thu, May 16, 2013 at 10:55:58PM +0200, Robert Richter wrote: > > iirc the reason was the different msr range that is switched on fam15h > > with a different counter to counter msr offset of 2 instead of 1. The > > code relies on the assumption that the msrs exist on that cpu. Thus > > the warning if not. Also note that code may have changed in 3.10 in > > that area. > > Stupid question: why is check_hw_exists() *after* the vendor-specific > counter detection code in init_hw_perf_events() even though it is > supposed to check whether hardware is emulated?
Mostly so that check_hw_exists() doesn't need to know about the vendor specifics like where the MSRs live, how many there are etc..
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