From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <2ce97e3af2b99d137f6909c256ddaf00@terzarima.net> To: 9fans@cse.psu.edu Subject: Re: [9fans] Current status of amd64 port? From: Charles Forsyth Date: Fri, 16 Nov 2007 23:56:38 +0000 In-Reply-To: <13426df10711161538q2b4fda69q1f37afbcaffecc74@mail.gmail.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="upas-thpkctlpgdcnfmyisnvcufypgf" Topicbox-Message-UUID: fda6c60a-ead2-11e9-9d60-3106f5b1d025 This is a multi-part message in MIME format. --upas-thpkctlpgdcnfmyisnvcufypgf Content-Disposition: inline Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit no, i meant that on a page fault, fault.c just does much the same read from the file that the system call would do, except it's more complicated to get there. ask = s->flen-soff; if(ask > BY2PG) ask = BY2PG; n = devtab[c->type]->read(c, kaddr, ask, daddr); if(n != ask) faulterror(Eioload, c, 0); (and that's also true on SunOS, Solaris, and probably Linux, except that on some it is really very complicated, not just more complicated than read.) the thing that saves it is the Image cache off to the side. --upas-thpkctlpgdcnfmyisnvcufypgf Content-Type: message/rfc822 Content-Disposition: inline Received: from mail.cse.psu.edu ([130.203.4.6]) by lavoro; Fri Nov 16 23:44:40 GMT 2007 Received: from psuvax1.cse.psu.edu (localhost [127.0.0.1]) by mail.cse.psu.edu (CSE Mail Server) with ESMTP id 97BB71234B for ; Fri, 16 Nov 2007 18:38:56 -0500 (EST) X-Original-To: 9fans@cse.psu.edu Delivered-To: 9fans@cse.psu.edu Received: from localhost (localhost [127.0.0.1]) by mail.cse.psu.edu (CSE Mail Server) with ESMTP id 0AA3012282 for <9fans@cse.psu.edu>; Fri, 16 Nov 2007 18:38:21 -0500 (EST) Received: from mail.cse.psu.edu ([127.0.0.1]) by localhost (psuvax1 [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 09625-01-92 for <9fans@cse.psu.edu>; Fri, 16 Nov 2007 18:38:18 -0500 (EST) Received: from wa-out-1112.google.com (wa-out-1112.google.com [209.85.146.176]) by mail.cse.psu.edu (CSE Mail Server) with ESMTP id 2B3581227E for <9fans@cse.psu.edu>; Fri, 16 Nov 2007 18:38:18 -0500 (EST) Received: by wa-out-1112.google.com with SMTP id v33so1118117wah for <9fans@cse.psu.edu>; Fri, 16 Nov 2007 15:38:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=4jsL+9X3VhhOlBBomi9CMg5ZuhpedIeEKUtVCoYCeik=; b=PQ6YOVIP9kB7oGNDsFI9KpfolpM+02glKx3NEmVjwMA3v+8Oj6rMRwouFoKfpiNYB6BXs8Ys6nuSqjqm/P2jABUV4y5HO1Qjyt1VziKXY22WMcJzUt+6CezJ0ub6Jq+85rKyf4x+dWYCL2ZWguexro2c6O64UdRX6FUhPCYVin8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=VzOdQkV42kaA2BsTjA1pbW9vVKb2cn1zZY6jMRMvAn70P7yQfazHEGkeSqH5WlOepc6wgPNm3ZOFEvGls8flzUmjc1lIPM3gA1xTmturSwT6TwRymBtfXFOYgATjnFHQxeX88MyrvtWqlZECfTTp3vHxZywKc8+FmgfplYwuBC4= Received: by 10.114.148.1 with SMTP id v1mr469235wad.1195256297367; Fri, 16 Nov 2007 15:38:17 -0800 (PST) Received: by 10.114.89.13 with HTTP; Fri, 16 Nov 2007 15:38:17 -0800 (PST) Message-ID: <13426df10711161538q2b4fda69q1f37afbcaffecc74@mail.gmail.com> Date: Fri, 16 Nov 2007 15:38:17 -0800 From: "ron minnich" To: "Fans of the OS Plan 9 from Bell Labs" <9fans@cse.psu.edu> Subject: Re: [9fans] Current status of amd64 port? In-Reply-To: <4bd0144e432da2706f14d20d1535239c@terzarima.net> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <4bd0144e432da2706f14d20d1535239c@terzarima.net> X-Virus-Scanned: by amavisd-new at cse.psu.edu X-BeenThere: 9fans@cse.psu.edu X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu> List-Id: Fans of the OS Plan 9 from Bell Labs <9fans.cse.psu.edu> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: 9fans-bounces+forsyth=terzarima.net@cse.psu.edu Errors-To: 9fans-bounces+forsyth=terzarima.net@cse.psu.edu On Nov 16, 2007 3:40 PM, Charles Forsyth wrote: > > that's a good question. i suppose you could argue not since > > a plan 9 kernel could get by without demand paging, it's just > > one of the kernel's dirty little secrets. > > it isn't really mmap'd as such: it does a read from a file into memory > so (as is usually the case on systems with mmap) it's quicker just to do > the read yourself, rather than suffer the page fault too. Well, I don't know Charles. When I was watching the page faults in the ports I did, the first page fault was for address 0x1020, first address in executable. I had assumed this was a demand paging case, now you are going to force me to go look :-) ron --upas-thpkctlpgdcnfmyisnvcufypgf--