Re: [PATCH v2] powerpc/uaccess: Use flexible addressing with __put_user()/__get_user()

From: Segher Boessenkool
Date: Wed Aug 12 2020 - 15:31:12 EST


On Wed, Aug 12, 2020 at 02:32:51PM +0200, Christophe Leroy wrote:
> Anyway, it seems that GCC doesn't make much use of the "m<>" and the
> pre-update form.

GCC does not use update form outside of inner loops much. Did you
expect anything else?

> Most of the benefit of flexible addressing seems to be
> achieved with patch 1 ie without the "m<>" constraint and update form.

Yes.


Segher