Re: [PATCH v1 05/29] xen/asm-generic: introduce stub header event.h

[Jan Beulich <jbeulich@xxxxxxxx>]

On 23.10.2023 12:23, Oleksii wrote:
> On Thu, 2023-10-19 at 11:18 +0200, Jan Beulich wrote:
>> On 14.09.2023 16:56, Oleksii Kurochko wrote:
>>> --- /dev/null
>>> +++ b/xen/include/asm-generic/event.h
>>> @@ -0,0 +1,39 @@
>>> +/* SPDX-License-Identifier: GPL-2.0-only */
>>> +#ifndef __ASM_GENERIC_EVENT_H__
>>> +#define __ASM_GENERIC_EVENT_H__
>>> +
>>> +#include <xen/sched.h>
>>> +
>>> +static inline void vcpu_mark_events_pending(struct vcpu *v)
>>> +{
>>> +}
>>
>> While this will satisfy callers from a build perspective, no port
>> will be functional with an implementation like this. Yet the
>> generic headers need to provide the required functionality, not
>> just build stubs.
> It makes sense but then we will have the similar patches when new
> architecture is introduced.
> 
>>
>> Going further in the series, I won't repeat this kind of comment.
>> Unless others disagree, my view is that headers put here should
>> be of use beyond initial bring-up of a new port.
>>
> Then we have two options here:
> 1. leave only declaration of the function.

Which would then require a stub to be introduced in the arch, or else
linking will fail (unless all calls can be compile-time eliminated,
which I doubt would be the case here).

As before a requirement (imo) is that headers introduced into
asm-generic/ are functional. An arch would introduce its own instance
if it wants to do certain things better, or if it has further needs.

Jan

> 2. remove it from asm-generic.
> 
> ~ Oleksii