On Tue, 2017-09-26 at 09:52 +0200, Greg Kroah-Hartman wrote: > On Mon, Sep 25, 2017 at 07:47:17PM +0100, Matthew Auld wrote: > > Not a fully blown gemfs, just our very own tmpfs kernel mount. Doing so > > moves us away from the shmemfs shm_mnt, and gives us the much needed > > flexibility to do things like set our own mount options, namely huge= > > which should allow us to enable the use of transparent-huge-pages for > > our shmem backed objects. > > > > v2: various improvements suggested by Joonas > > > > v3: move gemfs instance to i915.mm and simplify now that we have > > file_setup_with_mnt > > > > v4: fallback to tmpfs shm_mnt upon failure to setup gemfs > > > > v5: make tmpfs fallback kinder > > Why do this only for one specific driver? Shouldn't the drm core handle > this for you, for all other drivers as well? Otherwise trying to figure > out how to "contain" this type of thing is going to be a pain (mount > options, selinux options, etc.) We actually started quite grande by making stripped down version of shmemfs for drm core, but kept running into nacks about how we were implementing it (after getting a recommendation to try implementing it some way). After a few iterations and massive engineering time, we have been progressively reducing the amount of changes outside i915 in the hopes to get this merged. And all the while clock is ticking, so we thought the best way to get something to support our future work is to implement this first locally with minimal external changes outside i915 and then once we have something working, it'll be easier to generalize it for the drm core. Otherwise we'll never get to work with the huge page support, for which gemfs is the stepping stone here. So we're not planning on sitting on top of it, we'll just incubate it under i915/ so that it'll then be less pain for others to adopt when the biggest hurdles with core MM interactions are sorted out. Regards, Joonas -- Joonas Lahtinen Open Source Technology Center Intel Corporation -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
