Re: [PATCH 08/10] Don't invalidate dcache when option stack-cache is changed

Yao Qi
2013-11-18T14:02:43Z

On 11/18/2013 05:44 AM, Doug Evans wrote:
> If one wanted to remove the cache invalidation for the off->on
> transition that seems reasonable, but if I do a backtrace, turn the
> caching optimization off, and then do another backtrace, I'd want the
> second one to not use the cache. YMMV.

This behaviour is what we proposed in this patch.

>
> OTOH, if there was a command I could use to flush the cache after
> turning off the stack cache optimization, then I could see leaving the
> cache alone after the on->off transition. [I still think it'd be
> preferable to invalidate the cache, but I can live with asking users
> to live with having to manually flush the cache after turning off the
> optimization.]

IMO, cache to target memory is quite transparent to users. I can't
find a case that user has to flush or invalidate cache.

With this patch, we are lack of a way to flush the cache. I prefer to
add a new command to explicitly invalidate cache like "cache invalidate"
or "maint cache invalidate", if we think users really need this command.

--
Yao (é½å°§)