Re: [PATCH 1/5] xen/memory: Introduce CONFIG_ARCH_ACQUIRE_RESOURCE

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 30/07/2020 09:02, Paul Durrant wrote:
>> -----Original Message-----
>> From: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
>> Sent: 28 July 2020 12:37
>> To: Xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxxx>
>> Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>; Jan Beulich 
>> <JBeulich@xxxxxxxx>; Wei Liu <wl@xxxxxxx>;
>> Roger Pau Monné <roger.pau@xxxxxxxxxx>; Stefano Stabellini 
>> <sstabellini@xxxxxxxxxx>; Julien Grall
>> <julien@xxxxxxx>; Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>; Paul 
>> Durrant <paul@xxxxxxx>; Michał
>> Leszczyński <michal.leszczynski@xxxxxxx>; Hubert Jasudowicz 
>> <hubert.jasudowicz@xxxxxxx>
>> Subject: [PATCH 1/5] xen/memory: Introduce CONFIG_ARCH_ACQUIRE_RESOURCE
>>
>> New architectures shouldn't be forced to implement no-op stubs for unused
>> functionality.
>>
>> Introduce CONFIG_ARCH_ACQUIRE_RESOURCE which can be opted in to, and provide
>> compatibility logic in xen/mm.h
>>
>> No functional change.
> Code-wise, it looks fine, so...
>
> Reviewed-by: Paul Durrant <paul@xxxxxxx>

Thanks,

>
> ...but ...
>
>> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
>> ---
>> CC: Jan Beulich <JBeulich@xxxxxxxx>
>> CC: Wei Liu <wl@xxxxxxx>
>> CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
>> CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
>> CC: Julien Grall <julien@xxxxxxx>
>> CC: Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>
>> CC: Paul Durrant <paul@xxxxxxx>
>> CC: Michał Leszczyński <michal.leszczynski@xxxxxxx>
>> CC: Hubert Jasudowicz <hubert.jasudowicz@xxxxxxx>
>> ---
>>  xen/arch/x86/Kconfig     | 1 +
>>  xen/common/Kconfig       | 3 +++
>>  xen/include/asm-arm/mm.h | 8 --------
>>  xen/include/xen/mm.h     | 9 +++++++++
>>  4 files changed, 13 insertions(+), 8 deletions(-)
>>
>> diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig
>> index a636a4bb1e..e7644a0a9d 100644
>> --- a/xen/arch/x86/Kconfig
>> +++ b/xen/arch/x86/Kconfig
>> @@ -6,6 +6,7 @@ config X86
>>      select ACPI
>>      select ACPI_LEGACY_TABLES_LOOKUP
>>      select ARCH_SUPPORTS_INT128
>> +    select ARCH_ACQUIRE_RESOURCE
> ... I do wonder whether 'HAS_ACQUIRE_RESOURCE' is a better and more 
> descriptive name.

We don't have a coherent policy for how to categorise these things.  I
can change the name if you insist, but I'm not sure it makes a useful
difference.

~Andrew