Re: SLAB_TYPESAFE_BY_RCU without constructors (was Re: [PATCH v4 13/17] khwasan: add hooks implementation)

From: Dmitry Vyukov
Date: Wed Aug 01 2018 - 13:53:59 EST


On Wed, Aug 1, 2018 at 6:25 PM, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
> On 08/01/2018 09:22 AM, Christopher Lameter wrote:
>> On Wed, 1 Aug 2018, Eric Dumazet wrote:
>>
>>> The idea of having a ctor() would only be a win if all the fields that
>>> can be initialized in the ctor are contiguous and fill an integral
>>> number of cache lines.
>>
>> Ok. Its reducing code size and makes the object status more consistent.
>> Isn't that enough?
>>
>
> Prove it ;)
>
> I yet have to seen actual numbers.

Proving with numbers is required for a claimed performance improvement
at the cost of code degradation/increase. For a win-win change there
is really nothing to prove.