Re: [RFC PATCH 1/1] proc: introduce /proc/pid/lbr_stack

2015-02-28 Thread Peter Zijlstra
On Fri, Feb 27, 2015 at 03:57:02PM -0800, Andi Kleen wrote: On Fri, Feb 27, 2015 at 11:05:45PM +0100, Peter Zijlstra wrote: On Fri, Feb 27, 2015 at 09:54:34AM -0800, Andi Kleen wrote: perf record doesn't show where you're currently blocked. Of course it does; look at perf inject

Re: [RFC PATCH 1/1] proc: introduce /proc/pid/lbr_stack

2015-02-27 Thread Andi Kleen
On Fri, Feb 27, 2015 at 08:58:29AM +0100, Peter Zijlstra wrote: On Mon, Feb 23, 2015 at 09:44:48AM -0800, Andi Kleen wrote: On Mon, Feb 23, 2015 at 05:49:57PM +0100, Peter Zijlstra wrote: On Mon, Feb 23, 2015 at 03:43:41AM +, kan.li...@intel.com wrote: From: Kan Liang

Re: [RFC PATCH 1/1] proc: introduce /proc/pid/lbr_stack

2015-02-27 Thread Peter Zijlstra
On Fri, Feb 27, 2015 at 09:54:34AM -0800, Andi Kleen wrote: perf record doesn't show where you're currently blocked. Of course it does; look at perf inject -s. Trace points don't support the LBR stack. Yes, indeed. But would it not make much more sense to squirrel the LBR state into

Re: [RFC PATCH 1/1] proc: introduce /proc/pid/lbr_stack

2015-02-27 Thread Andi Kleen
On Fri, Feb 27, 2015 at 11:05:45PM +0100, Peter Zijlstra wrote: On Fri, Feb 27, 2015 at 09:54:34AM -0800, Andi Kleen wrote: perf record doesn't show where you're currently blocked. Of course it does; look at perf inject -s. Trace points don't support the LBR stack. Yes, indeed.

Re: [RFC PATCH 1/1] proc: introduce /proc/pid/lbr_stack

2015-02-26 Thread Peter Zijlstra
On Mon, Feb 23, 2015 at 09:44:48AM -0800, Andi Kleen wrote: On Mon, Feb 23, 2015 at 05:49:57PM +0100, Peter Zijlstra wrote: On Mon, Feb 23, 2015 at 03:43:41AM +, kan.li...@intel.com wrote: From: Kan Liang kan.li...@intel.com Haswell has a new feature that utilizes the existing

[RFC PATCH 1/1] proc: introduce /proc/pid/lbr_stack

2015-02-23 Thread kan . liang
From: Kan Liang kan.li...@intel.com Haswell has a new feature that utilizes the existing Last Branch Record facility to record call chains. It has been implemented in perf. The call chains information is saved during perf event context. This patch exposes a /proc/pid/lbr_stack file that shows

Re: [RFC PATCH 1/1] proc: introduce /proc/pid/lbr_stack

2015-02-23 Thread Peter Zijlstra
On Mon, Feb 23, 2015 at 03:43:41AM +, kan.li...@intel.com wrote: From: Kan Liang kan.li...@intel.com Haswell has a new feature that utilizes the existing Last Branch Record facility to record call chains. It has been implemented in perf. The call chains information is saved during perf

Re: [RFC PATCH 1/1] proc: introduce /proc/pid/lbr_stack

2015-02-23 Thread Andi Kleen
On Mon, Feb 23, 2015 at 05:49:57PM +0100, Peter Zijlstra wrote: On Mon, Feb 23, 2015 at 03:43:41AM +, kan.li...@intel.com wrote: From: Kan Liang kan.li...@intel.com Haswell has a new feature that utilizes the existing Last Branch Record facility to record call chains. It has been