From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1HTLsW-0006A9-4z for user-mode-linux-devel@lists.sourceforge.net; Mon, 19 Mar 2007 10:42:40 -0700 Received: from saraswathi.solana.com ([198.99.130.12]) by mail.sourceforge.net with esmtp (Exim 4.44) id 1HTLsV-0001EA-Lk for user-mode-linux-devel@lists.sourceforge.net; Mon, 19 Mar 2007 10:42:40 -0700 Date: Mon, 19 Mar 2007 13:40:38 -0400 From: Jeff Dike Message-ID: <20070319174038.GB11790@c2.user-mode-linux.org> References: <0A01463223B8164194908CAC85B66A1201AD3E57@ZMY16EXM67.ds.mot.com> Mime-Version: 1.0 Content-Disposition: inline In-Reply-To: <0A01463223B8164194908CAC85B66A1201AD3E57@ZMY16EXM67.ds.mot.com> Subject: Re: [uml-devel] Regarding context switching in UML. List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: user-mode-linux-devel-bounces@lists.sourceforge.net Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net To: Krishnappa Abhijith-A21204 Cc: user-mode-linux-devel@lists.sourceforge.net On Mon, Mar 19, 2007 at 11:01:40AM +0800, Krishnappa Abhijith-A21204 wrote: > Regarding Context switching in UML. > Each process running in UML will have corresponding process in HOST. In tt and skas0 mode, roughly yes. > So when the context switching in HOST happens, UML has to switch the > corresponding UML process by saving context etc... > will this be done by tracing thread.... Also how does process running in > HOST notifies UML to switch ? It does so by calling the UML's schedule(). The actual context switching is done by the outgoing process sleeping after waking up the incoming process. In tt mode, this is done by using a pipe as a semphore. A sleeping process is sleeping in read on a pipe, and will be woken up when an outgoing process writes a byte into the other end. > Also I've read in one of the article that UML schedules its process by > itself..? How this is done ? It has its own scheduler. The fact that you ask this question, and that you seem to think there is some sort of special relationship between UML and the host kernel, suggests that you have some basic misunderstandings. Jeff -- Work email - jdike at linux dot intel dot com ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel