From mboxrd@z Thu Jan 1 00:00:00 1970 From: Razvan Cojocaru Subject: Re: Multiple-page mem_event ring buffer? Date: Tue, 05 Mar 2013 17:35:13 +0200 Message-ID: <513610B1.9060506@gmail.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org >> Could I safely use more than one page for the ring buffer (passing '2' >> as the last parameter of xc_map_foreign_batch(), and so on), or am I >> limited to 1 page by design? > > You would have to change Xen itself to also view the N pages as a contiguous region in the virtual address space. I think vmap has been recently added for that purpose, but I know nothing about its limitations (cc'ing Jan). > > You would also want to retain the old interface and add a new domctl for N-page ring setup. And some refactoring of all the places where that sequence of calls needed for setup is repeated. And a pony ;) Ah, that's what I thought. Will ask management to budget for the pony :) Thanks, Razvan Cojocaru