From owner-freebsd-hackers@FreeBSD.ORG Mon May 10 15:35:44 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id B64D2106564A for ; Mon, 10 May 2010 15:35:44 +0000 (UTC) (envelope-from sam@errno.com) Received: from ebb.errno.com (ebb.errno.com [69.12.149.25]) by mx1.freebsd.org (Postfix) with ESMTP id 8BED88FC14 for ; Mon, 10 May 2010 15:35:44 +0000 (UTC) Received: from [172.24.98.37] ([192.75.139.252]) (authenticated bits=0) by ebb.errno.com (8.13.6/8.12.6) with ESMTP id o4AFNnlI056269 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Mon, 10 May 2010 08:23:52 -0700 (PDT) (envelope-from sam@errno.com) Message-Id: <892C86B0-81B0-433D-BF9C-7CDBD479F6CC@errno.com> From: Sam Leffler To: Oleksandr Tymoshenko In-Reply-To: <4BE46650.7010008@bluezbox.com> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v936) Date: Mon, 10 May 2010 08:23:48 -0700 References: <4BE46650.7010008@bluezbox.com> X-Mailer: Apple Mail (2.936) X-DCC--Metrics: ebb.errno.com; whitelist Cc: freebsd-hackers@freebsd.org Subject: Re: hifn(4) DMA fix for review X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 May 2010 15:35:44 -0000 On May 7, 2010, at 12:13 PM, Oleksandr Tymoshenko wrote: > Proposed patch addresses hifn(4) problems on FreeBSD/mips. Current > implementation keeps some of the state information (indexes in > buffers, etc) in DMA-mapped memory and bus_dma code invalidates them > during sync operations. This fix moves data that doesn't belong to DMA > ring to softc structure. > > Patch: http://people.freebsd.org/~gonzo/hifn.diff > Stats for original driver: > http://people.freebsd.org/~gonzo/hifn.stats.orig.txt > Stats for patched version: > http://people.freebsd.org/~gonzo/hifn.stats.patched.txt > > The changes look fine and make sense (did something similar for some other drivers for when the dma data structures were mapped uncached). I can't see any performance change in your stats; but I'm just eyeballing the numbers side-by-side. Was this on x86? (where there should be zero difference) It would be good to present these numbers better (e.g. curves on the same graph, ministat output, etc). Sam