On Mon, Mar 06, 2017 at 08:42:59AM +0100, Michal Hocko wrote:

On Fri 03-03-17 09:37:55, Laura Abbott wrote:

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On 03/03/2017 05:29 AM, Michal Hocko wrote:

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On Thu 02-03-17 13:44:32, Laura Abbott wrote:

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Hi,

There's been some recent discussions[1] about Ion-like frameworks. There's apparently interest in just keeping Ion since it works reasonablly well. This series does what should be the final clean ups for it to possibly be moved out of staging.

This includes the following:

• Some general clean up and removal of features that never got a lot of use as far as I can tell.
• Fixing up the caching. This is the series I proposed back in December[2] but never heard any feedback on. It will certainly break existing applications that rely on the implicit caching. I'd rather make an effort to move to a model that isn't going directly against the establishement though.
• Fixing up the platform support. The devicetree approach was never well recieved by DT maintainers. The proposal here is to think of Ion less as specifying requirements and more of a framework for exposing memory to userspace.
• CMA allocations now happen without the need of a dummy device structure. This fixes a bunch of the reasons why I attempted to add devicetree support before.

I've had problems getting feedback in the past so if I don't hear any major objections I'm going to send out with the RFC dropped to be picked up. The only reason there isn't a patch to come out of staging is to discuss any other changes to the ABI people might want. Once this comes out of staging, I really don't want to mess with the ABI.

Could you recapitulate concerns preventing the code being merged normally rather than through the staging tree and how they were addressed?

Sorry, I'm really not understanding your question here, can you clarify?

There must have been a reason why this code ended up in the staging tree, right? So my question is what those reasons were and how they were handled in order to move the code from the staging subtree.

No one gave a thing about android in upstream, so Greg KH just dumped it all into staging/android/. We've discussed ION a bunch of times, recorded anything we'd like to fix in staging/android/TODO, and Laura's patch series here addresses a big chunk of that.

This is pretty much the same approach we (gpu folks) used to de-stage the syncpt stuff. -Daniel