From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e5.ny.us.ibm.com (e5.ny.us.ibm.com [32.97.182.145]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e5.ny.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 3FC0467B23 for ; Thu, 1 Jun 2006 08:58:00 +1000 (EST) Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by e5.ny.us.ibm.com (8.12.11.20060308/8.12.11) with ESMTP id k4VMvv09028777 for ; Wed, 31 May 2006 18:57:57 -0400 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay02.pok.ibm.com (8.12.10/NCO/VER6.8) with ESMTP id k4VMvvDF119732 for ; Wed, 31 May 2006 18:57:57 -0400 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id k4VMvvf4017749 for ; Wed, 31 May 2006 18:57:57 -0400 Date: Wed, 31 May 2006 15:58:13 -0700 From: Mike Kravetz To: Paul Mackerras Subject: Re: Collecting hypervisor call stats Message-ID: <20060531225813.GC7909@w-mikek2.ibm.com> References: <20060531204144.GA7909@w-mikek2.ibm.com> <17534.7026.169023.420733@cargo.ozlabs.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <17534.7026.169023.420733@cargo.ozlabs.ibm.com> Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, Jun 01, 2006 at 08:40:50AM +1000, Paul Mackerras wrote: > I think that gathering those statistics would be useful. I suggest > you use a per-cpu array for them, to reduce the performance impact. Yes, that is a must do. We need to get a timestamp before and after the call. mftb should do the trick. Also, I'd prefer to have the code that stuffs the values into the array be C. So, the decision is to have the assembly code call out to the C routine -OR- create wrappers for the assembly routines. I much prefer C wrappers to touching the assembly. -- Mike