RE: [PATCH v3 12/16] KVM: arm64: handle pending bit for LPIs in ITS emulation

2015-10-12 Thread Pavel Fedin
Hello! > -Original Message- > From: kvm-ow...@vger.kernel.org [mailto:kvm-ow...@vger.kernel.org] On Behalf > Of Andre Przywara > Sent: Wednesday, October 07, 2015 5:55 PM > To: marc.zyng...@arm.com; christoffer.d...@linaro.org > Cc: eric.au...@linaro.org; p.fe...@samsung.com;

RE: [PATCH v3 12/16] KVM: arm64: handle pending bit for LPIs in ITS emulation

2015-10-12 Thread Pavel Fedin
Hello! > Shouldn't we also have 'break' here? If vgic_queue_irq() returns false, this > means we have no > more > LRs to use, therefore it makes no sense to keep iterating. No, don't listen to me. :) Because of piggyback, we indeed have to recheck all the interrupts. P.S. I still

Re: [PATCH v3 12/16] KVM: arm64: handle pending bit for LPIs in ITS emulation

2015-10-12 Thread Andre Przywara
Hi Pavel, On 12/10/15 08:40, Pavel Fedin wrote: > Hello! > >> -Original Message- >> From: kvm-ow...@vger.kernel.org [mailto:kvm-ow...@vger.kernel.org] On Behalf >> Of Andre Przywara >> Sent: Wednesday, October 07, 2015 5:55 PM >> To: marc.zyng...@arm.com; christoffer.d...@linaro.org >>

Re: [PATCH v3 12/16] KVM: arm64: handle pending bit for LPIs in ITS emulation

2015-10-07 Thread Marc Zyngier
On 07/10/15 16:10, Pavel Fedin wrote: > Hello! > >> As the actual LPI number in a guest can be quite high, but is mostly >> assigned using a very sparse allocation scheme, bitmaps and arrays >> for storing the virtual interrupt status are a waste of memory. >> We use our equivalent of the

RE: [PATCH v3 12/16] KVM: arm64: handle pending bit for LPIs in ITS emulation

2015-10-07 Thread Pavel Fedin
Hello! > As the actual LPI number in a guest can be quite high, but is mostly > assigned using a very sparse allocation scheme, bitmaps and arrays > for storing the virtual interrupt status are a waste of memory. > We use our equivalent of the "Interrupt Translation Table Entry" > (ITTE) to hold

Re: [PATCH v3 12/16] KVM: arm64: handle pending bit for LPIs in ITS emulation

2015-10-07 Thread Marc Zyngier
On 07/10/15 16:46, Pavel Fedin wrote: > Hello! > >> Sure. And you then have to parse and validate all the tables each and >> every time you're going to inject an interrupt (because the guest can >> change the table content behind your back). You are quickly going to >> notice that your

RE: [PATCH v3 12/16] KVM: arm64: handle pending bit for LPIs in ITS emulation

2015-10-07 Thread Pavel Fedin
Hello! > Sure. And you then have to parse and validate all the tables each and > every time you're going to inject an interrupt (because the guest can > change the table content behind your back). You are quickly going to > notice that your performance is abysmal. I don't see any real