drm/i915: Stop caching the "golden" renderstate

As we now record the default HW state and so only emit the "golden"
renderstate once to prepare the HW, there is no advantage in keeping the
renderstate batch around as it will never be used again.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171110142634.10551-8-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_drv.h

@@ -67,7 +67,6 @@
 #include "i915_gem_fence_reg.h"
 #include "i915_gem_object.h"
 #include "i915_gem_gtt.h"
-#include "i915_gem_render_state.h"
 #include "i915_gem_request.h"
 #include "i915_gem_timeline.h"
 

drivers/gpu/drm/i915/i915_gem_render_state.c

@@ -26,10 +26,12 @@
  */
 
 #include "i915_drv.h"
+#include "i915_gem_render_state.h"
 #include "intel_renderstate.h"
 
 struct intel_render_state {
 	const struct intel_renderstate_rodata *rodata;
+	struct drm_i915_gem_object *obj;
 	struct i915_vma *vma;
 	u32 batch_offset;
 	u32 batch_size;
@@ -40,6 +42,9 @@ struct intel_render_state {
 static const struct intel_renderstate_rodata *
 render_state_get_rodata(const struct intel_engine_cs *engine)
 {
+	if (engine->id != RCS)
+		return NULL;
+
 	switch (INTEL_GEN(engine->i915)) {
 	case 6:
 		return &gen6_null_state;
@@ -74,17 +79,16 @@ static int render_state_setup(struct intel_render_state *so,
 			      struct drm_i915_private *i915)
 {
 	const struct intel_renderstate_rodata *rodata = so->rodata;
-	struct drm_i915_gem_object *obj = so->vma->obj;
 	unsigned int i = 0, reloc_index = 0;
 	unsigned int needs_clflush;
 	u32 *d;
 	int ret;
 
-	ret = i915_gem_obj_prepare_shmem_write(obj, &needs_clflush);
+	ret = i915_gem_obj_prepare_shmem_write(so->obj, &needs_clflush);
 	if (ret)
 		return ret;
 
-	d = kmap_atomic(i915_gem_object_get_dirty_page(obj, 0));
+	d = kmap_atomic(i915_gem_object_get_dirty_page(so->obj, 0));
 
 	while (i < rodata->batch_items) {
 		u32 s = rodata->batch[i];
@@ -112,7 +116,7 @@ static int render_state_setup(struct intel_render_state *so,
 		goto err;
 	}
 
-	so->batch_offset = so->vma->node.start;
+	so->batch_offset = i915_ggtt_offset(so->vma);
 	so->batch_size = rodata->batch_items * sizeof(u32);
 
 	while (i % CACHELINE_DWORDS)
@@ -160,9 +164,9 @@ static int render_state_setup(struct intel_render_state *so,
 		drm_clflush_virt_range(d, i * sizeof(u32));
 	kunmap_atomic(d);
 
-	ret = i915_gem_object_set_to_gtt_domain(obj, false);
+	ret = i915_gem_object_set_to_gtt_domain(so->obj, false);
 out:
-	i915_gem_obj_finish_shmem_access(obj);
+	i915_gem_obj_finish_shmem_access(so->obj);
 	return ret;
 
 err:
@@ -173,112 +177,61 @@ static int render_state_setup(struct intel_render_state *so,
 
 #undef OUT_BATCH
 
-int i915_gem_render_state_init(struct intel_engine_cs *engine)
+int i915_gem_render_state_emit(struct drm_i915_gem_request *rq)
 {
-	struct intel_render_state *so;
-	const struct intel_renderstate_rodata *rodata;
-	struct drm_i915_gem_object *obj;
-	int ret;
+	struct intel_engine_cs *engine = rq->engine;
+	struct intel_render_state so = {}; /* keep the compiler happy */
+	int err;
 
-	if (engine->id != RCS)
+	so.rodata = render_state_get_rodata(engine);
+	if (!so.rodata)
 		return 0;
 
-	rodata = render_state_get_rodata(engine);
-	if (!rodata)
-		return 0;
-
-	if (rodata->batch_items * 4 > PAGE_SIZE)
+	if (so.rodata->batch_items * 4 > PAGE_SIZE)
 		return -EINVAL;
 
-	so = kmalloc(sizeof(*so), GFP_KERNEL);
-	if (!so)
-		return -ENOMEM;
-
-	obj = i915_gem_object_create_internal(engine->i915, PAGE_SIZE);
-	if (IS_ERR(obj)) {
-		ret = PTR_ERR(obj);
-		goto err_free;
-	}
+	so.obj = i915_gem_object_create_internal(engine->i915, PAGE_SIZE);
+	if (IS_ERR(so.obj))
+		return PTR_ERR(so.obj);
 
-	so->vma = i915_vma_instance(obj, &engine->i915->ggtt.base, NULL);
-	if (IS_ERR(so->vma)) {
-		ret = PTR_ERR(so->vma);
+	so.vma = i915_vma_instance(so.obj, &engine->i915->ggtt.base, NULL);
+	if (IS_ERR(so.vma)) {
+		err = PTR_ERR(so.vma);
 		goto err_obj;
 	}
 
-	so->rodata = rodata;
-	engine->render_state = so;
-	return 0;
-
-err_obj:
-	i915_gem_object_put(obj);
-err_free:
-	kfree(so);
-	return ret;
-}
-
-int i915_gem_render_state_emit(struct drm_i915_gem_request *req)
-{
-	struct intel_render_state *so;
-	int ret;
-
-	lockdep_assert_held(&req->i915->drm.struct_mutex);
-
-	so = req->engine->render_state;
-	if (!so)
-		return 0;
-
-	/* Recreate the page after shrinking */
-	if (!i915_gem_object_has_pages(so->vma->obj))
-		so->batch_offset = -1;
-
-	ret = i915_vma_pin(so->vma, 0, 0, PIN_GLOBAL | PIN_HIGH);
-	if (ret)
-		return ret;
+	err = i915_vma_pin(so.vma, 0, 0, PIN_GLOBAL | PIN_HIGH);
+	if (err)
+		goto err_vma;
 
-	if (so->vma->node.start != so->batch_offset) {
-		ret = render_state_setup(so, req->i915);
-		if (ret)
-			goto err_unpin;
-	}
+	err = render_state_setup(&so, rq->i915);
+	if (err)
+		goto err_unpin;
 
-	ret = req->engine->emit_flush(req, EMIT_INVALIDATE);
-	if (ret)
+	err = engine->emit_flush(rq, EMIT_INVALIDATE);
+	if (err)
 		goto err_unpin;
 
-	ret = req->engine->emit_bb_start(req,
-					 so->batch_offset, so->batch_size,
-					 I915_DISPATCH_SECURE);
-	if (ret)
+	err = engine->emit_bb_start(rq,
+				    so.batch_offset, so.batch_size,
+				    I915_DISPATCH_SECURE);
+	if (err)
 		goto err_unpin;
 
-	if (so->aux_size > 8) {
-		ret = req->engine->emit_bb_start(req,
-						 so->aux_offset, so->aux_size,
-						 I915_DISPATCH_SECURE);
-		if (ret)
+	if (so.aux_size > 8) {
+		err = engine->emit_bb_start(rq,
+					    so.aux_offset, so.aux_size,
+					    I915_DISPATCH_SECURE);
+		if (err)
 			goto err_unpin;
 	}
 
-	i915_vma_move_to_active(so->vma, req, 0);
+	i915_vma_move_to_active(so.vma, rq, 0);
 err_unpin:
-	i915_vma_unpin(so->vma);
-	return ret;
-}
-
-void i915_gem_render_state_fini(struct intel_engine_cs *engine)
-{
-	struct intel_render_state *so;
-	struct drm_i915_gem_object *obj;
-
-	so = fetch_and_zero(&engine->render_state);
-	if (!so)
-		return;
-
-	obj = so->vma->obj;
-
-	i915_vma_close(so->vma);
-	__i915_gem_object_release_unless_active(obj);
-
-	kfree(so);
+	i915_vma_unpin(so.vma);
+err_vma:
+	i915_vma_close(so.vma);
+err_obj:
+	__i915_gem_object_release_unless_active(so.obj);
+	return err;
 }

drivers/gpu/drm/i915/i915_gem_render_state.h

@@ -26,8 +26,6 @@
 
 struct drm_i915_gem_request;
 
-int i915_gem_render_state_init(struct intel_engine_cs *engine);
-int i915_gem_render_state_emit(struct drm_i915_gem_request *req);
-void i915_gem_render_state_fini(struct intel_engine_cs *engine);
+int i915_gem_render_state_emit(struct drm_i915_gem_request *rq);
 
 #endif /* _I915_GEM_RENDER_STATE_H_ */

drivers/gpu/drm/i915/intel_engine_cs.c

@@ -641,21 +641,15 @@ int intel_engine_init_common(struct intel_engine_cs *engine)
 	if (ret)
 		goto err_unpin_preempt;
 
-	ret = i915_gem_render_state_init(engine);
-	if (ret)
-		goto err_breadcrumbs;
-
 	if (HWS_NEEDS_PHYSICAL(engine->i915))
 		ret = init_phys_status_page(engine);
 	else
 		ret = init_status_page(engine);
 	if (ret)
-		goto err_rs_fini;
+		goto err_breadcrumbs;
 
 	return 0;
 
-err_rs_fini:
-	i915_gem_render_state_fini(engine);
 err_breadcrumbs:
 	intel_engine_fini_breadcrumbs(engine);
 err_unpin_preempt:
@@ -682,7 +676,6 @@ void intel_engine_cleanup_common(struct intel_engine_cs *engine)
 	else
 		cleanup_status_page(engine);
 
-	i915_gem_render_state_fini(engine);
 	intel_engine_fini_breadcrumbs(engine);
 	intel_engine_cleanup_cmd_parser(engine);
 	i915_gem_batch_pool_fini(&engine->batch_pool);

drivers/gpu/drm/i915/intel_lrc.c

@@ -136,6 +136,7 @@
 #include <drm/drmP.h>
 #include <drm/i915_drm.h>
 #include "i915_drv.h"
+#include "i915_gem_render_state.h"
 #include "intel_mocs.h"
 
 #define RING_EXECLIST_QFULL		(1 << 0x2)

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -28,9 +28,12 @@
  */
 
 #include <linux/log2.h>
+
 #include <drm/drmP.h>
-#include "i915_drv.h"
 #include <drm/i915_drm.h>
+
+#include "i915_drv.h"
+#include "i915_gem_render_state.h"
 #include "i915_trace.h"
 #include "intel_drv.h"
 

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -165,7 +165,6 @@ struct i915_ctx_workarounds {
 };
 
 struct drm_i915_gem_request;
-struct intel_render_state;
 
 /*
  * Engine IDs definitions.
@@ -307,7 +306,6 @@ struct intel_engine_cs {
 	struct intel_timeline *timeline;
 
 	struct drm_i915_gem_object *default_state;
-	struct intel_render_state *render_state;
 
 	atomic_t irq_count;
 	unsigned long irq_posted;