From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: xen/arm: Query - vgic nr_spis value for domU Date: Tue, 24 Feb 2015 12:50:10 +0000 Message-ID: <54EC7382.6040603@linaro.org> References: <1424770871.27930.268.camel@citrix.com> <54EC48F2.7020205@linaro.org> <1424773380.27930.298.camel@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" 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: Vijay Kilari , Ian Campbell Cc: Julien Grall , Stefano Stabellini , "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org Hi Vijay, On 24/02/15 10:49, Vijay Kilari wrote: > On Tue, Feb 24, 2015 at 3:53 PM, Ian Campbell wrote: >> On Tue, 2015-02-24 at 09:48 +0000, Julien Grall wrote: >>> >>> On 24/02/2015 09:41, Ian Campbell wrote: >>>> domU should get configurable nr_lpi in the same way Julien has done for >>>> spi. Unless it is possible to make nr_lpi dynamic based on the guests >>>> actual usage patterns (i.e. alloc on demand), that would be ok too. >>> >>> You have to expose the number of LPI's used in GICD_TYPER. >>> So unless we decide to use hardware value for the guest, we would have to >>> set a static one at domain creation. >> >> Right. >> >> With alloc on demand it might be reasonable to expose a pretty high >> number (like the h/w limit) in GICD_TYPER if the actual associated >> resources aren't actually allocated until they are used. > > I propose to add radix tree for each domain for pending_lpis > (synonymous to pending_irq for lpis) > and allocate pending_lpi structure whenever irq_descriptor is allocated/removed > Destroy this radix tree when domain is destroyed. I'm not sure what you mean by "allocating the pending_lpi whenever irq_descriptor is allocated/removed"... The irq_desc and pending_lpi should be allocated differently. Anyway, I guess it will be easier to understand with your upcoming patch series. Regards, -- Julien Grall