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

Tvrtko Ursulin
2019-05-15T11:44:41Z

On 10/05/2019 14:31, Chris Wilson wrote:
> 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?

Not sure I understand the question.

I am at the moment updating the series with review feedback and some
small thing here and there. When done with that I'll see if these VCS
hardcoded assumptions can be easily solved. Basically I will have a go
at integrating engine discovery which I think its definitely needed now
that I have added class based engine map building ability.

Regards,

Tvrtko

> Otherwise looks fine.
> -Chris