On Tue, Jun 24, 2014 at 04:45:05AM -0700, Mateo Lozano, Oscar wrote: > Ok, let´s try to extract something positive out of all this. > > OPTION A (Ben´s proposal): > > > I think the only solution for what Chris is asking for is to implement this > > as 1 > > context per engine, as opposed to 1 context with a context object per > > engine. As you correctly stated, I think we all agreed the latter was fine > > when > > we met. Functionally, I see no difference, but it does allow you to always > > use > > a context as the sole mechanism for making any decisions and performing > > any operations. Now without writing all the code, I can't promise it > > actually > > will look better, but I think it's likely going to be a lot cleaner. Before > > you do > > any changes though... > > We agreed on this early on (v1), yes, but then the idea was frowned upon by > Brad and then by Daniel. I cannot recall exactly why anymore, but one big > reason was that the idr mechanism makes it difficult to track several > contexts with the same id (and userspace only has one context handle) and > something about ctx->hang_stats. From v2 on, we agreed to multiplex different > engines inside one intel_context (and that´s why we renamed i915_hw_context > to intel_context).
Yeah, at least for me, the reason was that the multiple structs per context id code felt awkward given that most/all of the fields in a struct intel_context are logically per-context rather than per-engine (vm, hang_stats, etc). It didn't seem like the right approach to me at the time. Brad > > OPTION B (Brad´s proposal): > > > So I suggested that we: > > > > - Add a back pointer from struct intel_rinbuffer to intel_context (would > > only > > be valid for lrc mode) > > - Move the intel_ringbuffer_get(engine, context) calls up to the callers > > - Pass (engine, ringbuf) instead of (engine, context) to intel_ring_* > > functions > > - Have the vfunc implemenations get the context from the ringbuffer where > > needed and ignore it where not > > > > Looking again, we could probably add a back pointer to the intel_engine_cs > > as well and then just pass around the ringbuf. > > Sounds fine by me: intel_ringbuffer is only related to exactly one > intel_engine_cs and one intel_context, so having pointers to those two makes > sense. > As before, this could be easily done within the existing code (passing > intel_rinbgbuffer instead of intel_engine_cs), but Daniel wants a code split, > so I can only do it for the logical ring functions. _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
