On 12/6/24 09:08, Zi Yan wrote:
> On 6 Dec 2024, at 11:42, Matthew Wilcox wrote:
>
>> On Fri, Dec 06, 2024 at 09:19:38AM -0500, Zi Yan wrote:
>>> For architectures setting ARCH_HAS_CPU_CACHE_ALIASING, which requires
>>> flushing cache and arc, which sets folio->flags after clearing a user
>>> folio
>> I think arc just has some legacy code left that needs to be ripped out.
>> See commit d5272aaa8257 which took away ARCH_HAS_CPU_CACHE_ALIASING
>> from arc.
> The PG_dc_clean bit seems not to be related to cache aliasing.
> See commit eacd0e950dc2 ("ARC: [mm] Lazy D-cache flush (non aliasing VIPT)")
Indeed it is not related to aliasing.
>> Looking at 8690bbcf3b70, I wonder if you want to use
>> cpu_dcache_is_aliasing() here?
> Yeah, this is more precise. Will use this in my next version. Thanks.
Commit 8690bbcf3b70 was wrong for ARC as it assumed aliasing is true. The
aliasing D$ code is all gone and cpu_dcache_is_aliasing() is false for ARC now.
-vineet
