Re: [PATCH v2 -tip] perf: x86, add SandyBridge support

[Lin Ming <ming.m.lin@intel.com>]

On Tue, 2011-03-01 at 23:09 +0800, Stephane Eranian wrote:
> On Tue, Mar 1, 2011 at 4:07 PM, Lin Ming <ming.m.lin@intel.com> wrote:
> > On Tue, 2011-03-01 at 17:39 +0800, Stephane Eranian wrote:
> >> On Tue, Mar 1, 2011 at 9:57 AM, Stephane Eranian <eranian@google.com> wrote:
> >> > On Tue, Mar 1, 2011 at 9:45 AM, Lin Ming <ming.m.lin@intel.com> wrote:
> >> >> On Tue, 2011-03-01 at 15:43 +0800, Stephane Eranian wrote:
> >> >>> On Mon, Feb 28, 2011 at 10:15 AM, Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:
> >> >>> > On Mon, 2011-02-28 at 15:22 +0800, Lin Ming wrote:
> >> >>> >> This patch adds basic SandyBridge support, including hardware cache
> >> >>> >> events and PEBS events support.
> >> >>> >>
> >> >>> >> LLC-* hareware cache events don't work for now, it depends on the
> >> >>> >> offcore patches.
> >> >>> >
> >> >>> > What's the status of those, Stephane reported some problems last I
> >> >>> > remember?
> >> >>> >
> >> >>> I tried the trick I mentioned and it seems to work.
> >> >>>
> >> >>> Something like below with hwc->extra_alloc.
> >> >>> Could probably find a better name for that field.
> >> >>
> >> >> Stephane,
> >> >>
> >> >> I'll integrate below changes to the offcore patches, OK?
> >> >>
> >> > Let me try one more test on this.
> >> > I want to show the case the caused the problem in the first place.
> >> >
> >>
> >> There you go:
> >>
> >> $ task -e offcore_response_0:DMND_DATA_RD:local_dram -e
> >> offcore_response_0:DMND_DATA_RD:local_dram noploop 1
> >>
> >> Here the two instances of offcore_response are in two different event groups.
> >> I instrumented get/put percore constraint routines. get1 is where you do the
> >> first allocation, get2 is where you do ref++.
> >>
> >> The scheduling algorithm will do:
> >>   - submit 1st group
> >>   - schedule 1st group
> >>   - submit 2nd group
> >>   - schedule 1st + 2nd group
> >>
> >> Which results in the following trace:
> >>
> >> [  109.855713] CPU0 get1 cfg=1301b7 ref=1
> >> [  109.855717] CPU0 get2 cfg=1301b7 ref=2
> >> [  109.855718] CPU0 get2 cfg=1301b7 ref=3 <-- this one is bogus
> >> [  109.856606] CPU0 put cfg=1301b7 ref=2
> >> [  109.856609] CPU0 put cfg=1301b7 ref=1  <- don't free the resource
> >
> > Do you mean the issue is still there even with your extra_alloc patch
> > applied?
> >
> No, I am showing you what happens without it.
> If you try with it, it should work.

Got it. I'll send out a new version with all the fixes.

Thanks.

> 
> >>
> >> [  109.856616] CPU0 get2 cfg=1301b7 ref=2
> >> [  109.856619] CPU0 get2 cfg=1301b7 ref=3
> >> [  109.856622] CPU0 get2 cfg=1301b7 ref=4
> >> [  110.742151] CPU0 put cfg=1301b7 ref=3
> >> [  110.742154] CPU0 put cfg=1301b7 ref=2
> >>
> >> [  110.742160] CPU0 get2 cfg=1301b7 ref=3
> >> [  110.742161] CPU0 get2 cfg=1301b7 ref=4
> >> [  110.742163] CPU0 get2 cfg=1301b7 ref=5
> >> [  110.854448] CPU0 put cfg=1301b7 ref=4
> >> [  110.854450] CPU0 put cfg=1301b7 ref=3
> >
> >
> >