Re: [PATCH 12/18] drm/i915: Unify request submission

Joonas Lahtinen
2016-07-22T08:03:23Z

On ke, 2016-07-20 at 14:12 +0100, Chris Wilson wrote:
> Move request submission from emit_request into its own common vfunc
> from i915_add_request().
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/i915_gem_request.c    |  7 +++----
>  drivers/gpu/drm/i915/i915_guc_submission.c |  9 ++++++---
>  drivers/gpu/drm/i915/intel_guc.h           |  1 -
>  drivers/gpu/drm/i915/intel_lrc.c           | 10 +++-------
>  drivers/gpu/drm/i915/intel_ringbuffer.c    | 26 ++++++++++----------------
>  drivers/gpu/drm/i915/intel_ringbuffer.h    | 23 +++++++++++------------
>  6 files changed, 33 insertions(+), 43 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c
> index 408f390a4c98..3e633b47213c 100644
> --- a/drivers/gpu/drm/i915/i915_gem_request.c
> +++ b/drivers/gpu/drm/i915/i915_gem_request.c
> @@ -469,12 +469,10 @@ void __i915_add_request(struct drm_i915_gem_request *request,
>    */
>   request->postfix = intel_ring_get_tail(ring);
>
> - if (i915.enable_execlists)
> - ret = engine->emit_request(request);
> - else
> - ret = engine->add_request(request);
>   /* Not allowed to fail! */
> + ret = engine->emit_request(request);
>   WARN(ret, "emit|add_request failed: %d!\n", ret);

You should fix the message too; s/|add//

> +
>   /* Sanity check that the reserved size was large enough. */
>   ret = intel_ring_get_tail(ring) - request_start;
>   if (ret < 0)
> @@ -485,6 +483,7 @@ void __i915_add_request(struct drm_i915_gem_request *request,
>     reserved_tail, ret);
>
>   i915_gem_mark_busy(engine);
> + engine->submit_request(request);
>  }
>
>  static unsigned long local_clock_us(unsigned int *cpu)
> diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
> index eccd34832fe6..32d0e1890950 100644
> --- a/drivers/gpu/drm/i915/i915_guc_submission.c
> +++ b/drivers/gpu/drm/i915/i915_guc_submission.c
> @@ -585,7 +585,7 @@ static int guc_ring_doorbell(struct i915_guc_client *gc)
>   * The only error here arises if the doorbell hardware isn't functioning
>   * as expected, which really shouln't happen.
>   */
> -int i915_guc_submit(struct drm_i915_gem_request *rq)
> +static void i915_guc_submit(struct drm_i915_gem_request *rq)
>  {
>   unsigned int engine_id = rq->engine->id;
>   struct intel_guc *guc = &rq->i915->guc;
> @@ -602,8 +602,6 @@ int i915_guc_submit(struct drm_i915_gem_request *rq)
>
>   guc->submissions[engine_id] += 1;
>   guc->last_seqno[engine_id] = rq->fence.seqno;
> -
> - return b_ret;

Maybe we should have WARN(b_ret, "sumthing")? Although I see the return
value was not handled previously. CC'ing Dave to comment on too.

>  }
>
>  /*
> @@ -992,6 +990,7 @@ int i915_guc_submission_enable(struct drm_i915_private *dev_priv)
>  {
>   struct intel_guc *guc = &dev_priv->guc;
>   struct i915_guc_client *client;
> + struct intel_engine_cs *engine;
>
>   /* client for execbuf submission */
>   client = guc_client_alloc(dev_priv,
> @@ -1006,6 +1005,10 @@ int i915_guc_submission_enable(struct drm_i915_private *dev_priv)
>   host2guc_sample_forcewake(guc, client);
>   guc_init_doorbell_hw(guc);
>
> + /* Take over from manual control of ELSP (execlists) */
> + for_each_engine(engine, dev_priv)
> + engine->submit_request = i915_guc_submit;
> +
>   return 0;
>  }
>
> diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
> index 3e3e743740c0..623cf26cd784 100644
> --- a/drivers/gpu/drm/i915/intel_guc.h
> +++ b/drivers/gpu/drm/i915/intel_guc.h
> @@ -160,7 +160,6 @@ extern int intel_guc_resume(struct drm_device *dev);
>  int i915_guc_submission_init(struct drm_i915_private *dev_priv);
>  int i915_guc_submission_enable(struct drm_i915_private *dev_priv);
>  int i915_guc_wq_check_space(struct drm_i915_gem_request *rq);
> -int i915_guc_submit(struct drm_i915_gem_request *rq);
>  void i915_guc_submission_disable(struct drm_i915_private *dev_priv);
>  void i915_guc_submission_fini(struct drm_i915_private *dev_priv);
>
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index d17a193e8eaf..52edbcc9bca0 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -773,12 +773,6 @@ intel_logical_ring_advance_and_submit(struct drm_i915_gem_request *request)
>    */
>   request->previous_context = engine->last_context;
>   engine->last_context = request->ctx;
> -
> - if (i915.enable_guc_submission)
> - i915_guc_submit(request);
> - else
> - execlists_context_queue(request);
> -

Function name is still advance_and_submit, and now the call to submit
is moved to add_request, I'm confused.

>   return 0;
>  }
>
> @@ -1904,8 +1898,10 @@ logical_ring_default_vfuncs(struct intel_engine_cs *engine)
>  {
>   /* Default vfuncs which can be overriden by each engine. */
>   engine->init_hw = gen8_init_common_ring;
> - engine->emit_request = gen8_emit_request;
>   engine->emit_flush = gen8_emit_flush;
> + engine->emit_request = gen8_emit_request;
> + engine->submit_request = execlists_context_queue;

execlists_context_queue name could be changed too, just defined and one
calling site.

> +
>   engine->irq_enable = gen8_logical_ring_enable_irq;
>   engine->irq_disable = gen8_logical_ring_disable_irq;
>   engine->emit_bb_start = gen8_emit_bb_start;
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index 43dfa4be1cfd..907d933d62aa 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -1427,15 +1427,14 @@ static int gen6_signal(struct drm_i915_gem_request *signaller_req,
>  }
>
>  /**
> - * gen6_add_request - Update the semaphore mailbox registers
> + * gen6_emit_request - Update the semaphore mailbox registers
>   *
>   * @request - request to write to the ring
>   *
>   * Update the mailbox registers in the *other* rings with the current seqno.
>   * This acts like a signal in the canonical semaphore.
>   */
> -static int
> -gen6_add_request(struct drm_i915_gem_request *req)
> +static int gen6_emit_request(struct drm_i915_gem_request *req)
>  {
>   struct intel_ring *ring = req->ring;
>   int ret;
> @@ -1456,13 +1455,10 @@ gen6_add_request(struct drm_i915_gem_request *req)
>
>   req->tail = intel_ring_get_tail(ring);
>
> - req->engine->submit_request(req);
> -
>   return 0;
>  }
>
> -static int
> -gen8_render_add_request(struct drm_i915_gem_request *req)
> +static int gen8_render_emit_request(struct drm_i915_gem_request *req)
>  {
>   struct intel_engine_cs *engine = req->engine;
>   struct intel_ring *ring = req->ring;
> @@ -1486,8 +1482,9 @@ gen8_render_add_request(struct drm_i915_gem_request *req)
>   intel_ring_emit(ring, 0);
>   intel_ring_emit(ring, MI_USER_INTERRUPT);
>   intel_ring_emit(ring, MI_NOOP);
> + intel_ring_advance(ring);
>
> - req->engine->submit_request(req);
> + req->tail = intel_ring_get_tail(ring);

Ditto req->tail = ring->tail;

>
>   return 0;
>  }
> @@ -1692,8 +1689,7 @@ bsd_ring_flush(struct drm_i915_gem_request *req,
>   return 0;
>  }
>
> -static int
> -i9xx_add_request(struct drm_i915_gem_request *req)
> +static int i9xx_emit_request(struct drm_i915_gem_request *req)
>  {
>   struct intel_ring *ring = req->ring;
>   int ret;
> @@ -1710,8 +1706,6 @@ i9xx_add_request(struct drm_i915_gem_request *req)
>
>   req->tail = intel_ring_get_tail(ring);
>
> - req->engine->submit_request(req);
> -
>   return 0;
>  }
>
> @@ -2813,11 +2807,11 @@ static void intel_ring_default_vfuncs(struct drm_i915_private *dev_priv,
>         struct intel_engine_cs *engine)
>  {
>   engine->init_hw = init_ring_common;
> - engine->submit_request = i9xx_submit_request;
>
> - engine->add_request = i9xx_add_request;
> + engine->emit_request = i9xx_emit_request;
>   if (INTEL_GEN(dev_priv) >= 6)
> - engine->add_request = gen6_add_request;
> + engine->emit_request = gen6_emit_request;
> + engine->submit_request = i9xx_submit_request;
>
>   if (INTEL_GEN(dev_priv) >= 8)
>   engine->emit_bb_start = gen8_emit_bb_start;
> @@ -2846,7 +2840,7 @@ int intel_init_render_ring_buffer(struct intel_engine_cs *engine)
>
>   if (INTEL_GEN(dev_priv) >= 8) {
>   engine->init_context = intel_rcs_ctx_init;
> - engine->add_request = gen8_render_add_request;
> + engine->emit_request = gen8_render_emit_request;
>   engine->emit_flush = gen8_render_ring_flush;
>   if (i915.semaphores)
>   engine->semaphore.signal = gen8_rcs_signal;
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
> index 1a38c383327e..856b732ddbbd 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.h
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
> @@ -204,7 +204,17 @@ struct intel_engine_cs {
>
>   int (*init_context)(struct drm_i915_gem_request *req);
>
> - int (*add_request)(struct drm_i915_gem_request *req);
> + int (*emit_flush)(struct drm_i915_gem_request *request,
> +       u32 invalidate_domains,
> +       u32 flush_domains);
> + int (*emit_bb_start)(struct drm_i915_gem_request *req,
> +  u64 offset, u32 length,
> +  unsigned int dispatch_flags);
> +#define I915_DISPATCH_SECURE 0x1
> +#define I915_DISPATCH_PINNED 0x2
> +#define I915_DISPATCH_RS     0x4

Same here, maybe BIT(0) etc?

Really like how the code looks more consistent now!

Regards, Joonas

> + int (*emit_request)(struct drm_i915_gem_request *req);
> + void (*submit_request)(struct drm_i915_gem_request *req);
>   /* Some chipsets are not quite as coherent as advertised and need
>    * an expensive kick to force a true read of the up-to-date seqno.
>    * However, the up-to-date seqno is not always required and the last
> @@ -282,17 +292,6 @@ struct intel_engine_cs {
>   unsigned int idle_lite_restore_wa;
>   bool disable_lite_restore_wa;
>   u32 ctx_desc_template;
> - int (*emit_request)(struct drm_i915_gem_request *request);
> - int (*emit_flush)(struct drm_i915_gem_request *request,
> -       u32 invalidate_domains,
> -       u32 flush_domains);
> - int (*emit_bb_start)(struct drm_i915_gem_request *req,
> -  u64 offset, u32 length,
> -  unsigned int dispatch_flags);
> -#define I915_DISPATCH_SECURE 0x1
> -#define I915_DISPATCH_PINNED 0x2
> -#define I915_DISPATCH_RS     0x4
> - void (*submit_request)(struct drm_i915_gem_request *req);
>
>   /**
>    * List of objects currently involved in rendering from the
--
Joonas Lahtinen
Open Source Technology Center
Intel Corporation