Re: [Xen-devel] [PATCH 1/1] x86/xen: fix section of xen_init_time_ops() in header

[Andrew Cooper]

On 04/09/17 13:41, Jan Beulich wrote:
>>>> On 04.09.17 at 12:35, <andrew.cooper3@xxxxxxxxxx> wrote:
>> On 04/09/17 11:15, Jan Beulich wrote:
>>>>>> On 04.09.17 at 10:17, <jgross@xxxxxxxx> wrote:
>>>> On 03/09/17 10:38, Nicolas Iooss wrote:
>>>>> Commit d162809f85b4 ("xen/x86: Do not call xen_init_time_ops() until
>>>>> shared_info is initialized") moved xen_init_time_ops() from __init to
>>>>> __ref without updating xen-ops.h accordingly. Fix this.
>>>>>
>>>>> Fixes: d162809f85b4 ("xen/x86: Do not call xen_init_time_ops() until
>>>>> shared_info is initialized")
>>>>> Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@xxxxxxx>
>>>>> ---
>>>>>  arch/x86/xen/xen-ops.h | 2 +-
>>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
>>>>> index 0d5004477db6..b2a5d48a2c2a 100644
>>>>> --- a/arch/x86/xen/xen-ops.h
>>>>> +++ b/arch/x86/xen/xen-ops.h
>>>>> @@ -69,7 +69,7 @@ void xen_setup_runstate_info(int cpu);
>>>>>  void xen_teardown_timer(int cpu);
>>>>>  u64 xen_clocksource_read(void);
>>>>>  void xen_setup_cpu_clockevents(void);
>>>>> -void __init xen_init_time_ops(void);
>>>>> +void __ref xen_init_time_ops(void);
>>>>>  void __init xen_hvm_init_time_ops(void);
>>>> When correcting this could you please modify the prototypes to comply to
>>>> the intended form as noted in include/linux/init.h (the __ref or __init
>>>> annotations should be just before the ending semicolon)?
>>> Why would these annotations be kept on the declarations anyway?
>>> Attributes affecting code/data placement generally belong on the
>>> definitions only.
>> Because:
>>
>> a) Thatâs what the coding style says, and
>>
>> b) So various static analysis can be done (e.g. sparse) on an individual
>> translation unit basis.
>>
>>
>> Your objection to having annotations on declarations is why I've never
>> got around to adding sparse to the hypervisor build.
> Would you mind educating me what use these annotations can be
> for static analysis? If they're useful in headers, I would stop
> objecting to them being added there, but I'd then demand for them
> to never be present on non-static definitions (unless there are
> attributes where the compiler requires them to be repeated, but I
> think all attributes are cumulative).

For one, finding calls to __init functions from non __init functions.

~Andrew