[Intel-gfx] [PATCH 5/6] drm/i915: Track per drm client engine class busyness

[Tvrtko Ursulin]

On 07/02/2020 16:33, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2020-02-07 16:13:30)
>>   static inline void
>> -__intel_context_stats_start(struct intel_context *ce, ktime_t now)
>> +__intel_context_stats_start(struct intel_context *ce,
>> +                           struct intel_engine_cs *engine,
>> +                           ktime_t now)
>>   {
>>          struct intel_context_stats *stats = &ce->stats;
>> -
>> -       if (!stats->active) {
>> -               stats->start = now;
>> -               stats->active = true;
>> +       struct i915_gem_context *ctx;
>> +
>> +       if (stats->active)
>> +               return;
>> +
>> +       stats->start = now;
>> +       stats->active = true;
>> +
>> +       rcu_read_lock();
>> +       ctx = rcu_dereference(ce->gem_context);
>> +       if (ctx && ctx->client) {
> 
> I'd rather avoid having to dig into the GEM context down here next to
> the HW.
> 
> First thought would be to keep the stats local on the intel_context and
> for the client to chase collate them when the user reads the fd.
> 
> Hmm, didn't you structure it like so earlier? What made you change your
> mind?

Yes, it's in the cover letter - we must not have disappearing 
contributions - client can submit from one context for a bit, close it, 
and oops usage history lost.

ce->drm_client? :)


Regards,

Tvrtko