Re: [PATCH v7 1/2] xen: export do_block, add a parameter to enable local events delivery

[Keir Fraser <keir.xen@gmail.com>]

On 19/04/2013 17:23, "Stefano Stabellini" <stefano.stabellini@eu.citrix.com>
wrote:

> On Fri, 19 Apr 2013, Jan Beulich wrote:
>>>>> On 19.04.13 at 16:06, Stefano Stabellini
>>>>> <stefano.stabellini@eu.citrix.com> wrote:
>>> -static long do_block(void)
>>> +int do_block(int event_delivery_enable)
>> 
>> In the previous version you didn't need this new parameter, so
>> what changed since then?
> 
> I changed the ARM implementation of local_event_delivery_enable: now it
> clears PSR_IRQ_MASK (the interrupt flag). That is the correct behavior
> for the implementation of the SCHEDOP_block hypercall but it is not the
> right behavior for the WFI trap handler. In order to reuse this code, I
> had to add the event_delivery_enable parameter.

Given that basically you need special versions of both local_events_*()
calls in do_block() (in one case you nop it out, and in the other it is a
special case which ignores the irq mask), I think perhaps you are better
with your own version of do_block() rather than code sharing. It's only a
small function and it skanks up every caller in common code, and you're
practically abusing do_block() by trying to play nicely with it.

I would also suggest that _local_events_need_delivery() takes no parameter,
always ignores the mask, and instead push the mask check into
local_events_need_delivery(). Perhaps rename the former to
local_events_need_delivery_ignore_mask() or something.

 -- Keir

>> Also, please use bool_t for boolean parameters.
> 
> OK
> 
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