From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e36.co.us.ibm.com (e36.co.us.ibm.com [32.97.110.154]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e36.co.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 64AB667B95 for ; Thu, 17 Aug 2006 10:56:34 +1000 (EST) Received: from westrelay02.boulder.ibm.com (westrelay02.boulder.ibm.com [9.17.195.11]) by e36.co.us.ibm.com (8.12.11.20060308/8.12.11) with ESMTP id k7H0uUce015656 for ; Wed, 16 Aug 2006 20:56:30 -0400 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by westrelay02.boulder.ibm.com (8.13.6/8.13.6/NCO v8.1.1) with ESMTP id k7H0uCKK348540 for ; Wed, 16 Aug 2006 18:56:12 -0600 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id k7H0uB1Q012295 for ; Wed, 16 Aug 2006 18:56:12 -0600 Subject: Re: [RFC PATCH 1/4] powerpc 2.6.16-rt17: to build on powerpc w/ RT From: john stultz To: Benjamin Herrenschmidt In-Reply-To: <1155774368.11312.135.camel@localhost.localdomain> References: <17628.4499.609213.401518@cargo.ozlabs.ibm.com> <1155318983.5337.2.camel@localhost.localdomain> <1155771487.11312.114.camel@localhost.localdomain> <1155772859.15360.12.camel@localhost.localdomain> <1155774368.11312.135.camel@localhost.localdomain> Content-Type: text/plain Date: Wed, 16 Aug 2006 17:56:10 -0700 Message-Id: <1155776171.15360.22.camel@localhost.localdomain> Mime-Version: 1.0 Cc: linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Paul Mackerras , mingo@elte.hu, tglx@linutronix.de List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2006-08-17 at 02:26 +0200, Benjamin Herrenschmidt wrote: > > Hey Ben, > > I appreciate your looking over my patch. You are correct, the > > conversion is a bit rough and I've not yet been able to work on the > > powerpc vDSO, although I'd like to get it working so any help or > > suggestions would be appreciated (is there a reason the vDSO is written > > in ASM?). > > > > If you have any other concerns w/ that patch, or the generic timekeeping > > code, please let me know and I'll do what I can to address them. > > Well, I've been wanting to look at your stuff and possibly do the > conversion for some time, provided we don't lose performances ... Our > current implementation is very optimized to avoid even memory barriers > in most cases and I doubt we'll be able to be as fine tuned using your > generic code, thus it's a tradeoff decision that we have to do. But > then, I need to look into the details before doing any final > statement :) Ok, although do let me know if you see places where the generic code could use any of the optimizations used in powerpc. thanks -john