On Mon, Aug 28, 2017 at 8:44 PM, Noralf Trønnes <noralf@xxxxxxxxxxx> wrote: > Hi, > > Currently I'm using the cma library with tinydrm because it was so > simple to use even though I have to work around the fact that reads are > uncached. A bigger problem that I have become aware of, is that it > restricts the dma buffers it can import since they have to be continous. > > So I looked to udl and it uses shmem. Fine, let's make a shmem gem > library similar to the cma library. > > Now I have done so and have started to think about the DOC: section, > explaining what the library does. And I'm stuck, what's the benefit of > using shmem compared to just using alloc_page()? Gives you swapping (and eventually maybe even migration) since there's a real filesystem behind it. Atm this only works if you register a shrinker callback, which for display drivers is a bit overkill. See i915 or msm for examples (or ttm, if you want an entire fancy framework), and git grep shrinker -- drivers/gpu. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
