From owner-svn-src-user@FreeBSD.ORG Fri Mar 12 17:45:27 2010 Return-Path: Delivered-To: svn-src-user@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A4B30106566C; Fri, 12 Mar 2010 17:45:27 +0000 (UTC) (envelope-from john@baldwin.cx) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 7621D8FC16; Fri, 12 Mar 2010 17:45:27 +0000 (UTC) Received: from bigwig.baldwin.cx (66.111.2.69.static.nyinternet.net [66.111.2.69]) by cyrus.watson.org (Postfix) with ESMTPSA id 14B4046B3B; Fri, 12 Mar 2010 12:45:27 -0500 (EST) Received: from zion.baldwin.cx (pool-98-109-181-99.nwrknj.fios.verizon.net [98.109.181.99]) by bigwig.baldwin.cx (Postfix) with ESMTPA id 4C5BC8A026; Fri, 12 Mar 2010 12:45:26 -0500 (EST) From: John Baldwin To: Juli Mallett Date: Fri, 12 Mar 2010 12:03:44 -0500 User-Agent: KMail/1.12.4 (FreeBSD/7.3-PRERELEASE; KDE/4.3.4; i386; ; ) References: <201003112032.o2BKWTrG089154@svn.freebsd.org> In-Reply-To: <201003112032.o2BKWTrG089154@svn.freebsd.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201003121203.44340.john@baldwin.cx> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0.1 (bigwig.baldwin.cx); Fri, 12 Mar 2010 12:45:26 -0500 (EST) X-Virus-Scanned: clamav-milter 0.95.1 at bigwig.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-2.3 required=4.2 tests=AWL,BAYES_00, FH_HOST_EQ_VERIZON_P,RDNS_DYNAMIC autolearn=no version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on bigwig.baldwin.cx Cc: src-committers@freebsd.org, svn-src-user@freebsd.org Subject: Re: svn commit: r205025 - user/jmallett/octeon/sys/mips/mips X-BeenThere: svn-src-user@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the experimental " user" src tree" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Mar 2010 17:45:27 -0000 On Thursday 11 March 2010 03:32:29 pm Juli Mallett wrote: > Author: jmallett > Date: Thu Mar 11 20:32:28 2010 > New Revision: 205025 > URL: http://svn.freebsd.org/changeset/base/205025 > > Log: > I don't know that a critical section is required here, but if it is we > really don't want to get interrupted between reading the counter and > calculating the ticks. In practice I think cputicks are only queried while holding a spin lock (so interrupts are disabled). Part of the comment before this is wrong as the cputicks are completely divorced from the timecounter code, so the tc code handling wrapping doesn't help any. However, if there is a way to use a single instruction to read all 64-bits of the ticker on mips64, it would probably be best to add a mips64-specific ticker method and use that for set_cputicker() instead of this one. -- John Baldwin