Re: [PATCH v2 3/6] hw/char: pl011 don't keep setting the IRQ if nothing changed

2015-03-13 Thread Alex Bennée
Peter Maydell peter.mayd...@linaro.org writes: On 12 March 2015 at 15:51, Peter Maydell peter.mayd...@linaro.org wrote: On 4 March 2015 at 14:35, Alex Bennée alex.ben...@linaro.org wrote: While observing KVM traces I can see additional IRQ calls on pretty much every MMIO access which is just

Re: [PATCH v2 3/6] hw/char: pl011 don't keep setting the IRQ if nothing changed

2015-03-12 Thread Peter Maydell
On 4 March 2015 at 14:35, Alex Bennée alex.ben...@linaro.org wrote: While observing KVM traces I can see additional IRQ calls on pretty much every MMIO access which is just plain inefficient. Only update the QEMU IRQ level if something has actually changed from last time. Otherwise we may be

Re: [PATCH v2 3/6] hw/char: pl011 don't keep setting the IRQ if nothing changed

2015-03-12 Thread Peter Maydell
On 12 March 2015 at 15:51, Peter Maydell peter.mayd...@linaro.org wrote: On 4 March 2015 at 14:35, Alex Bennée alex.ben...@linaro.org wrote: While observing KVM traces I can see additional IRQ calls on pretty much every MMIO access which is just plain inefficient. Only update the QEMU IRQ

Re: [Qemu-devel] [PATCH v2 3/6] hw/char: pl011 don't keep setting the IRQ if nothing changed

2015-03-11 Thread Greg Bellows
On Wed, Mar 4, 2015 at 8:35 AM, Alex Bennée alex.ben...@linaro.org wrote: While observing KVM traces I can see additional IRQ calls on pretty much every MMIO access which is just plain inefficient. Only update the QEMU IRQ level if something has actually changed from last time. Otherwise we