Re: [Qemu-devel] [PATCH v14 2/5] intc/gic: Extract some reusable vGIC code

[Peter Maydell <peter.maydell@linaro.org>]

On 9 September 2015 at 08:49, Pavel Fedin <p.fedin@samsung.com> wrote:
> Some functions previously used only by vGICv2 are useful also for vGICv3
> implementation. Untie them from GICState and make accessible from within
> other modules:
> - kvm_arm_gic_set_irq()
> - kvm_gic_supports_attr() - moved to common code and renamed to
>   kvm_device_check_attr()
> - kvm_gic_access() - turned into GIC-independent kvm_device_access().
>   Data pointer changed to void * because some GICv3 registers are
>   64-bit wide
>
> Some of these changes are not used right now, but they will be helpful for
> implementing live migration.
>
> Actually kvm_dist_get() and kvm_dist_put() could also be made reusable, but
> they would require two extra parameters (s->dev_fd and s->num_cpu) as well as
> lots of typecasts of 's' to DeviceState * and back to GICState *. This makes
> the code very ugly so i decided to stop at this point. I tried also an
> approach with making a base class for all possible GICs, but it would contain
> only three variables (dev_fd, cpu_num and irq_num), and accessing them through
> the rest of the code would be again tedious (either ugly casts or qemu-style
> separate object pointer). So i disliked it too.
>
> Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
> Tested-by: Ashok kumar <ashoks@broadcom.com>

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM