[Intel-gfx] [PATCH v4 3/4] drm/i915: Consolidate checks for engine stats availability

[Sagar Arun Kamble]

On 11/28/2017 6:34 PM, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>
> Sagar noticed the check can be consolidated between the engine stats
> implementation and the PMU.
>
> My first choice was a static inline helper but that got into include
> ordering mess quickly fast so I went with a macro instead. At some point
> we should perhaps looking into taking out the non-ringubffer bits from
> intel_ringbuffer.h into a new intel_engine.h or something.
>
> v2: Use engine->flags. (Chris Wilson)
> v3: Rebase and mark GuC as not yet supported. (Chris Wilson)
> v4: Move flag setting to intel_engines_reset_default_submission.
>      (Chris Wilson)
>
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Suggested-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
> Cc: Sagar Arun Kamble <sagar.a.kamble at intel.com>
> Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk> (v2)
> ---
>   drivers/gpu/drm/i915/i915_pmu.c             | 11 ++++-------
>   drivers/gpu/drm/i915/intel_engine_cs.c      |  8 +++++---
>   drivers/gpu/drm/i915/intel_guc_submission.c |  2 ++
>   drivers/gpu/drm/i915/intel_lrc.c            |  2 ++
>   drivers/gpu/drm/i915/intel_ringbuffer.h     |  6 ++++++
>   5 files changed, 19 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
> index 3357b690ce90..c3c641ec962b 100644
> --- a/drivers/gpu/drm/i915/i915_pmu.c
> +++ b/drivers/gpu/drm/i915/i915_pmu.c
> @@ -90,11 +90,6 @@ static unsigned int event_enabled_bit(struct perf_event *event)
>   	return config_enabled_bit(event->attr.config);
>   }
>   
> -static bool supports_busy_stats(struct drm_i915_private *i915)
> -{
> -	return INTEL_GEN(i915) >= 8;
> -}
> -
>   static bool pmu_needs_timer(struct drm_i915_private *i915, bool gpu_active)
>   {
>   	u64 enable;
> @@ -123,8 +118,10 @@ static bool pmu_needs_timer(struct drm_i915_private *i915, bool gpu_active)
>   	/*
>   	 * Also there is software busyness tracking available we do not
>   	 * need the timer for I915_SAMPLE_BUSY counter.
> +	 *
> +	 * Use RCS as proxy for all engines.
>   	 */
> -	else if (supports_busy_stats(i915))
> +	else if (intel_engine_supports_stats(i915->engine[RCS]))
>   		enable &= ~BIT(I915_SAMPLE_BUSY);
>   
>   	/*
> @@ -447,7 +444,7 @@ static void i915_pmu_event_read(struct perf_event *event)
>   
>   static bool engine_needs_busy_stats(struct intel_engine_cs *engine)
>   {
> -	return supports_busy_stats(engine->i915) &&
> +	return intel_engine_supports_stats(engine) &&
>   	       (engine->pmu.enable & BIT(I915_SAMPLE_BUSY));
>   }
>   
> diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
> index d27e124d826a..a35f8d3a55fd 100644
> --- a/drivers/gpu/drm/i915/intel_engine_cs.c
> +++ b/drivers/gpu/drm/i915/intel_engine_cs.c
> @@ -1527,8 +1527,10 @@ void intel_engines_reset_default_submission(struct drm_i915_private *i915)
>   	struct intel_engine_cs *engine;
>   	enum intel_engine_id id;
>   
> -	for_each_engine(engine, i915, id)
> +	for_each_engine(engine, i915, id) {
>   		engine->set_default_submission(engine);
> +		engine->flags |= I915_ENGINE_SUPPORTS_STATS;
> +	}
>   }
>   
>   /**
> @@ -1829,7 +1831,7 @@ int intel_enable_engine_stats(struct intel_engine_cs *engine)
>   {
>   	unsigned long flags;
>   
> -	if (INTEL_GEN(engine->i915) < 8)
> +	if (!intel_engine_supports_stats(engine))
>   		return -ENODEV;
>   
>   	spin_lock_irqsave(&engine->stats.lock, flags);
> @@ -1890,7 +1892,7 @@ void intel_disable_engine_stats(struct intel_engine_cs *engine)
>   {
>   	unsigned long flags;
>   
> -	if (INTEL_GEN(engine->i915) < 8)
> +	if (!intel_engine_supports_stats(engine))
>   		return;
>   
>   	spin_lock_irqsave(&engine->stats.lock, flags);
> diff --git a/drivers/gpu/drm/i915/intel_guc_submission.c b/drivers/gpu/drm/i915/intel_guc_submission.c
> index cf1cc2cb6722..912ff143d531 100644
> --- a/drivers/gpu/drm/i915/intel_guc_submission.c
> +++ b/drivers/gpu/drm/i915/intel_guc_submission.c
> @@ -1453,6 +1453,8 @@ int intel_guc_submission_enable(struct intel_guc *guc)
>   		execlists->tasklet.func = guc_submission_tasklet;
>   		engine->park = guc_submission_park;
>   		engine->unpark = guc_submission_unpark;
> +
> +		engine->flags &= ~I915_ENGINE_SUPPORTS_STATS;
>   	}
>   
>   	return 0;
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index 479f880c0f2f..b811f7cddd7e 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -1983,6 +1983,8 @@ intel_engine_setup_execlist(struct intel_engine_cs *engine)
I am seeing intel_engine_init_execlist function in drm-tip. and that 
will get called for < gen 8 too so this
may not be right place. Setting it in logical_ring_setup and clearing in 
intel_init_ring_buffer is more clearer I guess.
>   
>   	execlists->queue = RB_ROOT;
>   	execlists->first = NULL;
> +
> +	engine->flags |= I915_ENGINE_SUPPORTS_STATS;
>   }
>   
>   static void
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
> index a91ce63b88b6..c68ab3ead83c 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.h
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
> @@ -540,6 +540,7 @@ struct intel_engine_cs {
>   	struct intel_engine_hangcheck hangcheck;
>   
>   #define I915_ENGINE_NEEDS_CMD_PARSER BIT(0)
> +#define I915_ENGINE_SUPPORTS_STATS   BIT(1)
>   	unsigned int flags;
>   
>   	/*
> @@ -604,6 +605,11 @@ static inline bool intel_engine_needs_cmd_parser(struct intel_engine_cs *engine)
>   	return engine->flags & I915_ENGINE_NEEDS_CMD_PARSER;
>   }
>   
> +static inline bool intel_engine_supports_stats(struct intel_engine_cs *engine)
> +{
> +	return engine->flags & I915_ENGINE_SUPPORTS_STATS;
> +}
> +
>   static inline void
>   execlists_set_active(struct intel_engine_execlists *execlists,
>   		     unsigned int bit)