From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v6a 17/17] xen/arm: Restrict saving of gic register for idle domain Date: Fri, 27 Jun 2014 16:03:52 +0100 Message-ID: <53AD87D8.9050409@linaro.org> References: <1403760849-14627-1-git-send-email-vijay.kilari@gmail.com> <1403760849-14627-18-git-send-email-vijay.kilari@gmail.com> <53AC2F21.7060800@linaro.org> <1403880347.3169.54.camel@kazak.uk.xensource.com> <1403880759.3169.61.camel@kazak.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1403880759.3169.61.camel@kazak.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: vijay.kilari@gmail.com, stefano.stabellini@eu.citrix.com, Prasun.Kapoor@caviumnetworks.com, vijaya.kumar@caviumnetworks.com, tim@xen.org, xen-devel@lists.xen.org, stefano.stabellini@citrix.com List-Id: xen-devel@lists.xenproject.org On 27/06/14 15:52, Ian Campbell wrote: > On Fri, 2014-06-27 at 15:45 +0100, Ian Campbell wrote: >> On Thu, 2014-06-26 at 15:33 +0100, Julien Grall wrote: >>> Hi Vijay, >>> >>> On 06/26/2014 06:34 AM, vijay.kilari@gmail.com wrote: >>>> From: Vijaya Kumar K >>>> >>>> Check for idle domain is missing before saving gic context >>> >>> Can you be a bit more verbose to explain why we don't need to save >>> context for idle vcpu? >> >> There's lots of state you don't need to save for an idle domain, this >> one seems pretty clear cut to me. > > Although it might be useful to consider whether the tail: > /* Disable until next VCPU scheduled */ > GICH[GICH_HCR] = 0; > isb(); > should be done for idle domains too. I suspect yes. I think we don't care as the virtual CPU interface will never used when an idle VCPU is running. Regards, -- Julien Grall