Re: perf: WARNING perfevents: irq loop stuck!

2015-05-18 Thread Vince Weaver
On Fri, 8 May 2015, Ingo Molnar wrote: > > * Ingo Molnar wrote: > > > > > * Vince Weaver wrote: > > > > > So this is just a warning, and I've reported it before, but the > > > perf_fuzzer triggers this fairly regularly on my Haswell system. > > > > > > It looks like fixed counter 0 (retire

Re: perf: WARNING perfevents: irq loop stuck!

2015-05-08 Thread Ingo Molnar
* Ingo Molnar wrote: > > * Vince Weaver wrote: > > > So this is just a warning, and I've reported it before, but the > > perf_fuzzer triggers this fairly regularly on my Haswell system. > > > > It looks like fixed counter 0 (retired instructions) being set to > > fffe occasiona

Re: perf: WARNING perfevents: irq loop stuck!

2015-05-08 Thread Ingo Molnar
* Vince Weaver wrote: > On Fri, 1 May 2015, Ingo Molnar wrote: > > > So fffe corresponds to 2 events left until overflow, > > right? And on Haswell we don't set x86_pmu.limit_period AFAICS, so we > > allow these super short periods. > > > > Maybe like on Broadwell we need a quirk

Re: perf: WARNING perfevents: irq loop stuck!

2015-05-07 Thread Vince Weaver
On Fri, 1 May 2015, Ingo Molnar wrote: > So fffe corresponds to 2 events left until overflow, > right? And on Haswell we don't set x86_pmu.limit_period AFAICS, so we > allow these super short periods. > > Maybe like on Broadwell we need a quirk on Nehalem/Haswell as well, > one sim

Re: perf: WARNING perfevents: irq loop stuck!

2015-05-01 Thread Vince Weaver
On Fri, 1 May 2015, Ingo Molnar wrote: > > * Vince Weaver wrote: > > > So this is just a warning, and I've reported it before, but the > > perf_fuzzer triggers this fairly regularly on my Haswell system. > > > > It looks like fixed counter 0 (retired instructions) being set to > > ff

Re: perf: WARNING perfevents: irq loop stuck!

2015-05-01 Thread Ingo Molnar
* Vince Weaver wrote: > So this is just a warning, and I've reported it before, but the > perf_fuzzer triggers this fairly regularly on my Haswell system. > > It looks like fixed counter 0 (retired instructions) being set to > fffe occasionally causes an irq loop storm and gets >