From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 77157B7102 for ; Sat, 25 Sep 2010 08:11:20 +1000 (EST) Subject: Re: ppc44x - how do i optimize driver for tlb hits From: Benjamin Herrenschmidt To: Ayman El-Khashab In-Reply-To: <20100924130851.GA14016@crust.elkhashab.com> References: <20100923151246.GA17015@crust.elkhashab.com> <1285279264.5158.18.camel@pasglop> <20100923223516.GA30033@crust.elkhashab.com> <1285290444.14081.6.camel@pasglop> <20100924025849.GA5619@crust.elkhashab.com> <1285303432.14081.28.camel@pasglop> <20100924103034.GA27958@zod.rchland.ibm.com> <20100924130851.GA14016@crust.elkhashab.com> Content-Type: text/plain; charset="UTF-8" Date: Sat, 25 Sep 2010 08:11:04 +1000 Message-ID: <1285366264.14081.33.camel@pasglop> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 2010-09-24 at 08:08 -0500, Ayman El-Khashab wrote: > > I suppose another option is to to use the kernel profiling option I > always see but have never used. Is that a viable option to figure out > what is happening here? With perf and stochastic sampling ? If you sample fast enough... but you'll mostly point to your routine I suppose... though it might tell you statistically where in your code, which -might- help. Cheers, Ben.