[Intel-gfx] [PATCH 056/190] drm/i915: Unify intel_ring_begin()

Chris Wilson chris at chris-wilson.co.uk
Mon Jan 11 01:17:07 PST 2016


Combine the near identical implementations of intel_logical_ring_begin()
and intel_ring_begin() - the only difference is that the logical wait
has to check for a matching ring (which is assumed by legacy).

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/intel_lrc.c        | 141 ++------------------------------
 drivers/gpu/drm/i915/intel_lrc.h        |   1 -
 drivers/gpu/drm/i915/intel_mocs.c       |  12 +--
 drivers/gpu/drm/i915/intel_ringbuffer.c | 111 +++++++++++++------------
 4 files changed, 69 insertions(+), 196 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index dc4fc9d8612c..3d14b69632e8 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -698,48 +698,6 @@ int intel_logical_ring_alloc_request_extras(struct drm_i915_gem_request *request
 	return 0;
 }
 
-static int logical_ring_wait_for_space(struct drm_i915_gem_request *req,
-				       int bytes)
-{
-	struct intel_ringbuffer *ringbuf = req->ringbuf;
-	struct intel_engine_cs *ring = req->ring;
-	struct drm_i915_gem_request *target;
-	unsigned space;
-	int ret;
-
-	if (intel_ring_space(ringbuf) >= bytes)
-		return 0;
-
-	/* The whole point of reserving space is to not wait! */
-	WARN_ON(ringbuf->reserved_in_use);
-
-	list_for_each_entry(target, &ring->request_list, list) {
-		/*
-		 * The request queue is per-engine, so can contain requests
-		 * from multiple ringbuffers. Here, we must ignore any that
-		 * aren't from the ringbuffer we're considering.
-		 */
-		if (target->ringbuf != ringbuf)
-			continue;
-
-		/* Would completion of this request free enough space? */
-		space = __intel_ring_space(target->postfix, ringbuf->tail,
-					   ringbuf->size);
-		if (space >= bytes)
-			break;
-	}
-
-	if (WARN_ON(&target->list == &ring->request_list))
-		return -ENOSPC;
-
-	ret = i915_wait_request(target);
-	if (ret)
-		return ret;
-
-	ringbuf->space = space;
-	return 0;
-}
-
 /*
  * intel_logical_ring_advance_and_submit() - advance the tail and submit the workload
  * @request: Request to advance the logical ringbuffer of.
@@ -763,89 +721,6 @@ intel_logical_ring_advance_and_submit(struct drm_i915_gem_request *request)
 		execlists_context_queue(request);
 }
 
-static void __wrap_ring_buffer(struct intel_ringbuffer *ringbuf)
-{
-	int rem = ringbuf->size - ringbuf->tail;
-	memset(ringbuf->virtual_start + ringbuf->tail, 0, rem);
-
-	ringbuf->tail = 0;
-	intel_ring_update_space(ringbuf);
-}
-
-static int logical_ring_prepare(struct drm_i915_gem_request *req, int bytes)
-{
-	struct intel_ringbuffer *ringbuf = req->ringbuf;
-	int remain_usable = ringbuf->effective_size - ringbuf->tail;
-	int remain_actual = ringbuf->size - ringbuf->tail;
-	int ret, total_bytes, wait_bytes = 0;
-	bool need_wrap = false;
-
-	if (ringbuf->reserved_in_use)
-		total_bytes = bytes;
-	else
-		total_bytes = bytes + ringbuf->reserved_size;
-
-	if (unlikely(bytes > remain_usable)) {
-		/*
-		 * Not enough space for the basic request. So need to flush
-		 * out the remainder and then wait for base + reserved.
-		 */
-		wait_bytes = remain_actual + total_bytes;
-		need_wrap = true;
-	} else {
-		if (unlikely(total_bytes > remain_usable)) {
-			/*
-			 * The base request will fit but the reserved space
-			 * falls off the end. So only need to to wait for the
-			 * reserved size after flushing out the remainder.
-			 */
-			wait_bytes = remain_actual + ringbuf->reserved_size;
-			need_wrap = true;
-		} else if (total_bytes > ringbuf->space) {
-			/* No wrapping required, just waiting. */
-			wait_bytes = total_bytes;
-		}
-	}
-
-	if (wait_bytes) {
-		ret = logical_ring_wait_for_space(req, wait_bytes);
-		if (unlikely(ret))
-			return ret;
-
-		if (need_wrap)
-			__wrap_ring_buffer(ringbuf);
-	}
-
-	return 0;
-}
-
-/**
- * intel_logical_ring_begin() - prepare the logical ringbuffer to accept some commands
- *
- * @req: The request to start some new work for
- * @num_dwords: number of DWORDs that we plan to write to the ringbuffer.
- *
- * The ringbuffer might not be ready to accept the commands right away (maybe it needs to
- * be wrapped, or wait a bit for the tail to be updated). This function takes care of that
- * and also preallocates a request (every workload submission is still mediated through
- * requests, same as it did with legacy ringbuffer submission).
- *
- * Return: non-zero if the ringbuffer is not ready to be written to.
- */
-int intel_logical_ring_begin(struct drm_i915_gem_request *req, int num_dwords)
-{
-	int ret;
-
-	WARN_ON(req == NULL);
-
-	ret = logical_ring_prepare(req, num_dwords * sizeof(uint32_t));
-	if (ret)
-		return ret;
-
-	req->ringbuf->space -= num_dwords * sizeof(uint32_t);
-	return 0;
-}
-
 int intel_logical_ring_reserve_space(struct drm_i915_gem_request *request)
 {
 	/*
@@ -858,7 +733,7 @@ int intel_logical_ring_reserve_space(struct drm_i915_gem_request *request)
 	 */
 	intel_ring_reserved_space_reserve(request->ringbuf, MIN_SPACE_FOR_ADD_REQUEST);
 
-	return intel_logical_ring_begin(request, 0);
+	return intel_ring_begin(request, 0);
 }
 
 /**
@@ -928,7 +803,7 @@ int intel_execlists_submission(struct i915_execbuffer_params *params,
 
 	if (ring == &dev_priv->ring[RCS] &&
 	    instp_mode != dev_priv->relative_constants_mode) {
-		ret = intel_logical_ring_begin(params->request, 4);
+		ret = intel_ring_begin(params->request, 4);
 		if (ret)
 			return ret;
 
@@ -1104,7 +979,7 @@ static int intel_logical_ring_workarounds_emit(struct drm_i915_gem_request *req)
 	if (ret)
 		return ret;
 
-	ret = intel_logical_ring_begin(req, w->count * 2 + 2);
+	ret = intel_ring_begin(req, w->count * 2 + 2);
 	if (ret)
 		return ret;
 
@@ -1566,7 +1441,7 @@ static int intel_logical_ring_emit_pdps(struct drm_i915_gem_request *req)
 	const int num_lri_cmds = GEN8_LEGACY_PDPES * 2;
 	int i, ret;
 
-	ret = intel_logical_ring_begin(req, num_lri_cmds * 2 + 2);
+	ret = intel_ring_begin(req, num_lri_cmds * 2 + 2);
 	if (ret)
 		return ret;
 
@@ -1611,7 +1486,7 @@ static int gen8_emit_bb_start(struct drm_i915_gem_request *req,
 		req->ctx->ppgtt->pd_dirty_rings &= ~intel_ring_flag(req->ring);
 	}
 
-	ret = intel_logical_ring_begin(req, 4);
+	ret = intel_ring_begin(req, 4);
 	if (ret)
 		return ret;
 
@@ -1655,7 +1530,7 @@ static int gen8_emit_flush(struct drm_i915_gem_request *request,
 	uint32_t cmd;
 	int ret;
 
-	ret = intel_logical_ring_begin(request, 4);
+	ret = intel_ring_begin(request, 4);
 	if (ret)
 		return ret;
 
@@ -1722,7 +1597,7 @@ static int gen8_emit_flush_render(struct drm_i915_gem_request *request,
 			vf_flush_wa = true;
 	}
 
-	ret = intel_logical_ring_begin(request, vf_flush_wa ? 12 : 6);
+	ret = intel_ring_begin(request, vf_flush_wa ? 12 : 6);
 	if (ret)
 		return ret;
 
@@ -1779,7 +1654,7 @@ static int gen8_emit_request(struct drm_i915_gem_request *request)
 	 * used as a workaround for not being allowed to do lite
 	 * restore with HEAD==TAIL (WaIdleLiteRestore).
 	 */
-	ret = intel_logical_ring_begin(request, 8);
+	ret = intel_ring_begin(request, 8);
 	if (ret)
 		return ret;
 
diff --git a/drivers/gpu/drm/i915/intel_lrc.h b/drivers/gpu/drm/i915/intel_lrc.h
index 9d4aa699e593..32401e11cebe 100644
--- a/drivers/gpu/drm/i915/intel_lrc.h
+++ b/drivers/gpu/drm/i915/intel_lrc.h
@@ -60,7 +60,6 @@ int intel_logical_ring_reserve_space(struct drm_i915_gem_request *request);
 void intel_logical_ring_stop(struct intel_engine_cs *ring);
 void intel_logical_ring_cleanup(struct intel_engine_cs *ring);
 int intel_logical_rings_init(struct drm_device *dev);
-int intel_logical_ring_begin(struct drm_i915_gem_request *req, int num_dwords);
 
 int logical_ring_flush_all_caches(struct drm_i915_gem_request *req);
 
diff --git a/drivers/gpu/drm/i915/intel_mocs.c b/drivers/gpu/drm/i915/intel_mocs.c
index d8a7fdc7baeb..5d4f6f3b67cd 100644
--- a/drivers/gpu/drm/i915/intel_mocs.c
+++ b/drivers/gpu/drm/i915/intel_mocs.c
@@ -200,11 +200,9 @@ static int emit_mocs_control_table(struct drm_i915_gem_request *req,
 	if (WARN_ON(table->size > GEN9_NUM_MOCS_ENTRIES))
 		return -ENODEV;
 
-	ret = intel_logical_ring_begin(req, 2 + 2 * GEN9_NUM_MOCS_ENTRIES);
-	if (ret) {
-		DRM_DEBUG("intel_logical_ring_begin failed %d\n", ret);
+	ret = intel_ring_begin(req, 2 + 2 * GEN9_NUM_MOCS_ENTRIES);
+	if (ret)
 		return ret;
-	}
 
 	intel_ring_emit(ringbuf, MI_LOAD_REGISTER_IMM(GEN9_NUM_MOCS_ENTRIES));
 
@@ -257,11 +255,9 @@ static int emit_mocs_l3cc_table(struct drm_i915_gem_request *req,
 	if (WARN_ON(table->size > GEN9_NUM_MOCS_ENTRIES))
 		return -ENODEV;
 
-	ret = intel_logical_ring_begin(req, 2 + GEN9_NUM_MOCS_ENTRIES);
-	if (ret) {
-		DRM_DEBUG("intel_logical_ring_begin failed %d\n", ret);
+	ret = intel_ring_begin(req, 2 + GEN9_NUM_MOCS_ENTRIES);
+	if (ret)
 		return ret;
-	}
 
 	intel_ring_emit(ringbuf,
 			MI_LOAD_REGISTER_IMM(GEN9_NUM_MOCS_ENTRIES / 2));
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 86c54584f64a..c694f602a0b8 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -2062,46 +2062,6 @@ void intel_cleanup_ring_buffer(struct intel_engine_cs *ring)
 	ring->dev = NULL;
 }
 
-static int ring_wait_for_space(struct intel_engine_cs *ring, int n)
-{
-	struct intel_ringbuffer *ringbuf = ring->buffer;
-	struct drm_i915_gem_request *request;
-	unsigned space;
-	int ret;
-
-	if (intel_ring_space(ringbuf) >= n)
-		return 0;
-
-	/* The whole point of reserving space is to not wait! */
-	WARN_ON(ringbuf->reserved_in_use);
-
-	list_for_each_entry(request, &ring->request_list, list) {
-		space = __intel_ring_space(request->postfix, ringbuf->tail,
-					   ringbuf->size);
-		if (space >= n)
-			break;
-	}
-
-	if (WARN_ON(&request->list == &ring->request_list))
-		return -ENOSPC;
-
-	ret = i915_wait_request(request);
-	if (ret)
-		return ret;
-
-	ringbuf->space = space;
-	return 0;
-}
-
-static void __wrap_ring_buffer(struct intel_ringbuffer *ringbuf)
-{
-	int rem = ringbuf->size - ringbuf->tail;
-	memset(ringbuf->virtual_start + ringbuf->tail, 0, rem);
-
-	ringbuf->tail = 0;
-	intel_ring_update_space(ringbuf);
-}
-
 int intel_ring_idle(struct intel_engine_cs *ring)
 {
 	struct drm_i915_gem_request *req;
@@ -2188,9 +2148,59 @@ void intel_ring_reserved_space_end(struct intel_ringbuffer *ringbuf)
 	ringbuf->reserved_in_use = false;
 }
 
-static int __intel_ring_prepare(struct intel_engine_cs *ring, int bytes)
+static int wait_for_space(struct drm_i915_gem_request *req, int bytes)
 {
-	struct intel_ringbuffer *ringbuf = ring->buffer;
+	struct intel_ringbuffer *ringbuf = req->ringbuf;
+	struct intel_engine_cs *ring = req->ring;
+	struct drm_i915_gem_request *target;
+	unsigned space;
+	int ret;
+
+	if (intel_ring_space(ringbuf) >= bytes)
+		return 0;
+
+	/* The whole point of reserving space is to not wait! */
+	WARN_ON(ringbuf->reserved_in_use);
+
+	list_for_each_entry(target, &ring->request_list, list) {
+		/*
+		 * The request queue is per-engine, so can contain requests
+		 * from multiple ringbuffers. Here, we must ignore any that
+		 * aren't from the ringbuffer we're considering.
+		 */
+		if (target->ringbuf != ringbuf)
+			continue;
+
+		/* Would completion of this request free enough space? */
+		space = __intel_ring_space(target->postfix, ringbuf->tail,
+					   ringbuf->size);
+		if (space >= bytes)
+			break;
+	}
+
+	if (WARN_ON(&target->list == &ring->request_list))
+		return -ENOSPC;
+
+	ret = i915_wait_request(target);
+	if (ret)
+		return ret;
+
+	ringbuf->space = space;
+	return 0;
+}
+
+static void ring_wrap(struct intel_ringbuffer *ringbuf)
+{
+	int rem = ringbuf->size - ringbuf->tail;
+	memset(ringbuf->virtual_start + ringbuf->tail, 0, rem);
+
+	ringbuf->tail = 0;
+	intel_ring_update_space(ringbuf);
+}
+
+static int ring_prepare(struct drm_i915_gem_request *req, int bytes)
+{
+	struct intel_ringbuffer *ringbuf = req->ringbuf;
 	int remain_usable = ringbuf->effective_size - ringbuf->tail;
 	int remain_actual = ringbuf->size - ringbuf->tail;
 	int ret, total_bytes, wait_bytes = 0;
@@ -2224,33 +2234,26 @@ static int __intel_ring_prepare(struct intel_engine_cs *ring, int bytes)
 	}
 
 	if (wait_bytes) {
-		ret = ring_wait_for_space(ring, wait_bytes);
+		ret = wait_for_space(req, wait_bytes);
 		if (unlikely(ret))
 			return ret;
 
 		if (need_wrap)
-			__wrap_ring_buffer(ringbuf);
+			ring_wrap(ringbuf);
 	}
 
 	return 0;
 }
 
-int intel_ring_begin(struct drm_i915_gem_request *req,
-		     int num_dwords)
+int intel_ring_begin(struct drm_i915_gem_request *req, int num_dwords)
 {
-	struct intel_engine_cs *ring;
-	struct drm_i915_private *dev_priv;
 	int ret;
 
-	WARN_ON(req == NULL);
-	ring = req->ring;
-	dev_priv = req->i915;
-
-	ret = __intel_ring_prepare(ring, num_dwords * sizeof(uint32_t));
+	ret = ring_prepare(req, num_dwords * sizeof(uint32_t));
 	if (ret)
 		return ret;
 
-	ring->buffer->space -= num_dwords * sizeof(uint32_t);
+	req->ringbuf->space -= num_dwords * sizeof(uint32_t);
 	return 0;
 }
 
-- 
2.7.0.rc3



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