Messages in this thread | | | Date | Fri, 10 Sep 2010 18:37:27 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH 0/3 v2] nmi perf fixes |
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* Robert Richter <robert.richter@amd.com> wrote:
> On 10.09.10 10:46:34, Ingo Molnar wrote: > > > > * Don Zickus <dzickus@redhat.com> wrote: > > > > > On Fri, Sep 10, 2010 at 01:41:40PM +0200, Peter Zijlstra wrote: > > > > On Thu, 2010-09-02 at 15:07 -0400, Don Zickus wrote: > > > > > Fixes to allow unknown nmis to pass through the perf nmi handler instead > > > > > of being swallowed. Contains patches that are already in Ingo's tree. Added > > > > > here for completeness. Based on ingo/tip > > > > > > > > > > Tested on intel/amd > > > > > > > > > > v2: patch cleanups and consolidation, no code changes > > > > > > > > > > Don Zickus (1): > > > > > perf, x86: Fix accidentally ack'ing a second event on intel perf > > > > > counter > > > > > > > > > > Peter Zijlstra (1): > > > > > perf, x86: Fix handle_irq return values > > > > > > > > > > Robert Richter (1): > > > > > perf, x86: Try to handle unknown nmis with an enabled PMU > > > > > > > > > > arch/x86/kernel/cpu/perf_event.c | 59 +++++++++++++++++++++++++------- > > > > > arch/x86/kernel/cpu/perf_event_intel.c | 15 +++++--- > > > > > arch/x86/kernel/cpu/perf_event_p4.c | 2 +- > > > > > 3 files changed, 56 insertions(+), 20 deletions(-) > > > > > > > > Both Ingo and I are getting Dazed and confused on our AMD machines, it > > > > started before yesterday (that is, after backing out all my recent > > > > changes it still gets dazed), so I suspect this set. > > > > > > > > I'll look at getting a trace of the thing, but if any of you has a > > > > bright idea... > > > > > > What are you running to create the problem? I can try and duplicate > > > it here. > > > > It happens easily here - just running something like: > > > > perf record -g ./hackbench 10 > > I try to reproduce it, which systems are affected?
This is an older Barcelona box, will send you a dump of details off-list.
> > a couple of times triggers it. Note, unlike with the earlier bug, > > the NMIs are not permanently 'stuck' - and everything continues > > working. Obviously the messages are nasty looking so this is a > > regression we need to fix. > > The patch below adds ratelimits.
This doesnt solve things though - even one unnecessary message will confuse users.
Ingo
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