RE: Another approach of UFSHPB

From: Avri Altman
Date: Tue May 26 2020 - 02:15:51 EST


> On 2020-05-24 22:40, Daejun Park wrote:
> > The HPB driver is close to the UFS core function, but it is not essential
> > for operating UFS device. With reference to this article
> > (https://lwn.net/Articles/645810/), we implemented extended UFS-feature
> > as bus model. Because the HPB driver consumes the user's main memory, it
> should
> > support bind / unbind functionality as needed. We implemented the HPB
> driver
> > can be unbind / unload on runtime.
>
> I do not agree that the bus model is the best choice for freeing cache
> memory if it is no longer needed. A shrinker is probably a much better
> choice because the callback functions in a shrinker get invoked when a
> system is under memory pressure. See also register_shrinker(),
> unregister_shrinker() and struct shrinker in include/linux/shrinker.h.
Since this discussion is closely related to cache allocation,
What is your opinion about allocating the pages dynamically as the regions
Are being activated/deactivated, in oppose of how it is done today -
Statically on init for the entire max-active-subregions?