From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from oss.sgi.com (localhost [127.0.0.1]) by oss.sgi.com (8.12.3/8.12.3) with ESMTP id g3PJWlwJ021980 for ; Thu, 25 Apr 2002 12:32:47 -0700 Received: (from majordomo@localhost) by oss.sgi.com (8.12.3/8.12.3/Submit) id g3PJWl6Z021979 for linux-mips-outgoing; Thu, 25 Apr 2002 12:32:47 -0700 X-Authentication-Warning: oss.sgi.com: majordomo set sender to owner-linux-mips@oss.sgi.com using -f Received: from sgi.com (sgi-too.SGI.COM [204.94.211.39]) by oss.sgi.com (8.12.3/8.12.3) with SMTP id g3PJWhwJ021975 for ; Thu, 25 Apr 2002 12:32:43 -0700 Received: from av.mvista.com (gateway-1237.mvista.com [12.44.186.158]) by sgi.com (980327.SGI.8.8.8-aspam/980304.SGI-aspam: SGI does not authorize the use of its proprietary systems or networks for unsolicited or bulk email from the Internet.) via ESMTP id MAA05022 for ; Thu, 25 Apr 2002 12:32:57 -0700 (PDT) mail_from (jsun@mvista.com) Received: from mvista.com (av [127.0.0.1]) by av.mvista.com (8.9.3/8.9.3) with ESMTP id LAA17551; Thu, 25 Apr 2002 11:45:30 -0700 Message-ID: <3CC84EEC.8060100@mvista.com> Date: Thu, 25 Apr 2002 11:46:04 -0700 From: Jun Sun User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.2.1) Gecko/20010901 X-Accept-Language: en-us MIME-Version: 1.0 To: Atsushi Nemoto CC: turcotte@broadcom.com, linux-mips@oss.sgi.com, mturc@broadcom.com Subject: Re: Linux Shared Memory Issue References: <3CC72BA3.90600@mvista.com> <20020425.142518.85417141.nemoto@toshiba-tops.co.jp> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mips@oss.sgi.com Precedence: bulk Atsushi Nemoto wrote: >>>>>>On Wed, 24 Apr 2002 15:03:15 -0700, Jun Sun said: >>>>>> > jsun> Looks like the infamous cache aliasing problem. Steve > jsun> Longerbeam had a patch which may help. Please try it and let me > jsun> know the results. > > jsun> +#define COLOUR_ALIGN(addr) (((addr)+SHMLBA-1)&~(SHMLBA-1)) > > Recent sparc64's COLOUR_ALIGN macro have pgoff argument like this. > We should do it same way for MIPS? > > #define COLOUR_ALIGN(addr,pgoff) \ > ((((addr)+SHMLBA-1)&~(SHMLBA-1)) + \ > (((pgoff)< What is the purpose of adding the pgoff part? To avoid mapping all shared regions into the beginning of cache? Jun