From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juergen Gross Subject: Re: Cpu pools discussion Date: Wed, 29 Jul 2009 14:33:14 +0200 Message-ID: <4A70418A.5000302@ts.fujitsu.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: Tim Deegan , George Dunlap , Zhigang Wang , "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org Keir Fraser wrote: > On 29/07/2009 12:06, "Juergen Gross" wrote: > >> Would you feel better if I'd try to eliminate the reason for cpupool_borrow? >> This function is needed only for continue_hypercall_on_cpu outside of the >> current pool. I think it should be possible to replace those by >> on_selected_cpus with less impact on the whole system. > > Some of the stuff in the continuation handlers cannot be executed in irq > context. 'Fixing' that would make many of the users ugly and less > maintainable, so getting borrow/return right is the better answer I think. The alternative would be a tasklet set up in irq. And we are speaking of 3 users. I could try a patch and then we could compare the two solutions. What do you think? Juergen -- Juergen Gross Principal Developer Operating Systems TSP ES&S SWE OS6 Telephone: +49 (0) 89 636 47950 Fujitsu Technolgy Solutions e-mail: juergen.gross@ts.fujitsu.com Otto-Hahn-Ring 6 Internet: ts.fujitsu.com D-81739 Muenchen Company details: ts.fujitsu.com/imprint.html