Re: [igt-dev] [PATCH i-g-t 05/21] wsim/media-bench: i915 balancing

Chris Wilson
2019-05-13T12:54:10Z

Quoting Tvrtko Ursulin (2019-05-13 13:41:47)
>
> On 10/05/2019 14:14, Chris Wilson wrote:
> > Quoting Tvrtko Ursulin (2019-05-08 13:10:42)
> >> From: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> >>
> >> Support i915 virtual engine from gem_wsim (-b i915) and media-bench.pl
> >>
> >> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> >> ---
> >> + /*
> >> + * Create and configure contexts.
> >> + */
> >> + for (i = 0; i < wrk->nr_ctxs; i += 2) {
> >> + struct ctx *ctx = &wrk->ctx_list[i];
> >> + uint32_t ctx_id, share_vm = 0;
> >>
> >> - wrk->ctx_list[w->context].id = arg.ctx_id;
> >> + if (ctx->id)
> >> + continue;
> >>
> >> - if (flags & GLOBAL_BALANCE) {
> >> - wrk->ctx_list[w->context].static_vcs = context_vcs_rr;
> >> - context_vcs_rr ^= 1;
> >> - } else {
> >> - wrk->ctx_list[w->context].static_vcs = ctx_vcs;
> >> - ctx_vcs ^= 1;
> >> - }
> >> + if (flags & I915) {
> >
> > vm sharing shouldn't be a i915-balancer only option. For single jobs split
> > across multiple contexts, I would expect they will want to share vm.
>
> Could do but I wanted to limit the new features to new features. :)
> Pencil in for later okay?

Sure. Just checking I'm in the same ballpark with my understanding. I
did hope to enable vm sharing here by default -- in reality, I doubt
these wsim are impacted by vm switches as they are tiny. However, I
don't have any measurements for shared vm, and had better start
somewhere.
-Chris