Messages in this thread | | | Date | Thu, 5 Jun 2014 18:47:44 +0200 | Subject | Re: [PATCH 9/9] perf/x86: add syfs entry to disable HT bug workaround | From | Stephane Eranian <> |
| |
On Thu, Jun 5, 2014 at 6:39 PM, Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com> wrote: > On Thu, Jun 5, 2014 at 6:17 PM, Borislav Petkov <bp@alien8.de> wrote: >> On Thu, Jun 05, 2014 at 05:45:24PM +0300, Maria Dimakopoulou wrote: >>> The issue is that the outcoming leaked counts are not compensated >>> by the incoming leaked counts of the sibling thread. With the workaround, >>> corrupting events are always scheduled with an empty sibling counter. >>> This means that their leaked counts are lost. So it is expected to see >>> lower counts with the workaround. Note that this is not a side-effect of >>> the workaround; leaked counts are expected to be lost with nothing >>> measured on the sibling counter in general. >>> >>> In a second series we intend to re-integrate the counts for counting mode >>> events. The workaround makes this easier because it guarantees >>> that the sibling counter is unused, thus its counts are purely leaked >>> counts and they can be safely re-integrated. >> >> IIUC, sounds to me like reintegrating the leaked counts from the unused >> counter should be part of the workaround too, not a second series... >> > > This series aims to avoid corruption of non-corrupting events. > Re-integration of the counts is not related to this. This is why > we chose to fix this other problem on a second series to keep > things clean and concepts separated. > I agree with Maria here. The reintegration is different problem. The series here helps and is a required first step. Reintegration will be added asap.
>> -- >> Regards/Gruss, >> Boris. >> >> Sent from a fat crate under my desk. Formatting is fine. >> --
| |