From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: Re: oprofile and ARM A9 hardware counter Date: Mon, 30 Jan 2012 17:24:38 +0000 Message-ID: <20120130172438.GC17814@mudshark.cambridge.arm.com> References: <20120127171009.GL2347@mudshark.cambridge.arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: oprofile-list-bounces@lists.sourceforge.net To: "eranian@gmail.com" Cc: =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= , "Cousson, Benoit" , Ming Lei , "santosh.shilimkar@ti.com" , "oprofile-list@lists.sourceforge.net" , "linux-omap@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" List-Id: linux-omap@vger.kernel.org On Mon, Jan 30, 2012 at 05:15:53PM +0000, stephane eranian wrote: > Still need to investigate why the frequency mode does > not yield the correct number of samples even with low frequency. > > > $ taskset -c 1 perf record -e cycles -F 100 noploop 10 > $ perf report -D | tail -20 > Aggregated stats: > TOTAL events: 475 > MMAP events: 11 > COMM events: 2 > EXIT events: 2 > SAMPLE events: 460 > cycles stats: > TOTAL events: 475 > MMAP events: 11 > COMM events: 2 > EXIT events: 2 > SAMPLE events: 460 > > 460 samples is way too low. Should be 100x10 = 1000 samples or close to it. Can you stick noploop.c somewhere (I'm lazy :) and I'll try it on one of my A9 boards? Thanks, Will ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Mon, 30 Jan 2012 17:24:38 +0000 Subject: oprofile and ARM A9 hardware counter In-Reply-To: References: <20120127171009.GL2347@mudshark.cambridge.arm.com> Message-ID: <20120130172438.GC17814@mudshark.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Jan 30, 2012 at 05:15:53PM +0000, stephane eranian wrote: > Still need to investigate why the frequency mode does > not yield the correct number of samples even with low frequency. > > > $ taskset -c 1 perf record -e cycles -F 100 noploop 10 > $ perf report -D | tail -20 > Aggregated stats: > TOTAL events: 475 > MMAP events: 11 > COMM events: 2 > EXIT events: 2 > SAMPLE events: 460 > cycles stats: > TOTAL events: 475 > MMAP events: 11 > COMM events: 2 > EXIT events: 2 > SAMPLE events: 460 > > 460 samples is way too low. Should be 100x10 = 1000 samples or close to it. Can you stick noploop.c somewhere (I'm lazy :) and I'll try it on one of my A9 boards? Thanks, Will