Re: [igt-dev] [PATCH i-g-t 14/21] gem_wsim: Engine map load balance command

Chris Wilson
2019-05-10T13:31:56Z

Quoting Tvrtko Ursulin (2019-05-08 13:10:51)
> From: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
>
> A new workload command for enabling a load balanced context map (aka
> Virtual Engine). Example usage:
>
> B.1
>
> This turns on load balancing for context one, assuming it has already been
> configured with an engine map. Only DEFAULT engine specifier can be used
> with load balanced engine maps.

Restriction makes sense for keeping linenoise^W file format simple.

> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> ---
> @@ -1172,6 +1210,8 @@ prepare_workload(unsigned int id, struct workload *wrk, unsigned int flags)
> if (ctx->engine_map) {
> I915_DEFINE_CONTEXT_PARAM_ENGINES(set_engines,
> ctx->engine_map_count + 1);
> + I915_DEFINE_CONTEXT_ENGINES_LOAD_BALANCE(load_balance,
> + ctx->engine_map_count);
> struct drm_i915_gem_context_param param = {
> .ctx_id = ctx_id,
> .param = I915_CONTEXT_PARAM_ENGINES,
> @@ -1179,7 +1219,25 @@ prepare_workload(unsigned int id, struct workload *wrk, unsigned int flags)
> .value = to_user_pointer(&set_engines),
> };
>
> - set_engines.extensions = 0;
> + if (ctx->wants_balance) {
> + set_engines.extensions =
> + to_user_pointer(&load_balance);
> +
> + memset(&load_balance, 0, sizeof(load_balance));
> + load_balance.base.name =
> + I915_CONTEXT_ENGINES_EXT_LOAD_BALANCE;
> + load_balance.num_siblings =
> + ctx->engine_map_count;
> +
> + for (j = 0; j < ctx->engine_map_count; j++) {
> + load_balance.engines[j].engine_class =
> + I915_ENGINE_CLASS_VIDEO; /* FIXME */
> + load_balance.engines[j].engine_instance =
> + ctx->engine_map[j] - VCS1; /* FIXME */

Ok, more fallout from fixing ctx->engine_map[] first?

Otherwise looks fine.
-Chris