Re: [PATCH 3/3] perf, x86: Add INST_RETIRED.ALL workarounds

2015-03-23 Thread Ingo Molnar
* Peter Zijlstra wrote: > On Mon, Mar 23, 2015 at 11:39:00AM +0100, Ingo Molnar wrote: > > > http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/5th-gen-core-family-spec-update.pdf > > > > > > BDM11 and BDM55 (not 57) tell us that the PMU will generate crap output

Re: [PATCH 3/3] perf, x86: Add INST_RETIRED.ALL workarounds

2015-03-23 Thread Peter Zijlstra
On Mon, Mar 23, 2015 at 11:39:00AM +0100, Ingo Molnar wrote: > > http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/5th-gen-core-family-spec-update.pdf > > > > BDM11 and BDM55 (not 57) tell us that the PMU will generate crap output > > if you don't do this. Non-fatal

Re: [PATCH 3/3] perf, x86: Add INST_RETIRED.ALL workarounds

2015-03-23 Thread Ingo Molnar
* Peter Zijlstra wrote: > On Mon, Mar 23, 2015 at 10:38:54AM +0100, Ingo Molnar wrote: > > > > * Andi Kleen wrote: > > > > > From: Andi Kleen > > > > > > On Broadwell INST_RETIRED.ALL cannot be used with any period > > > that doesn't have the lowest 6 bits cleared. And the period > > > shou

Re: [PATCH 3/3] perf, x86: Add INST_RETIRED.ALL workarounds

2015-03-23 Thread Peter Zijlstra
On Mon, Mar 23, 2015 at 10:38:54AM +0100, Ingo Molnar wrote: > > * Andi Kleen wrote: > > > From: Andi Kleen > > > > On Broadwell INST_RETIRED.ALL cannot be used with any period > > that doesn't have the lowest 6 bits cleared. And the period > > should not be smaller than 128. > > Sloppy chang

Re: [PATCH 3/3] perf, x86: Add INST_RETIRED.ALL workarounds

2015-03-23 Thread Ingo Molnar
* Andi Kleen wrote: > From: Andi Kleen > > On Broadwell INST_RETIRED.ALL cannot be used with any period > that doesn't have the lowest 6 bits cleared. And the period > should not be smaller than 128. Sloppy changelog: a most basic question is not answered by the changelog: what happens in pr