drm/i915: Extract intel_frontbuffer active tracking

Move the active tracking for the frontbuffer operations out of the
i915_gem_object and into its own first class (refcounted) object. In the
process of detangling, we switch from low level request tracking to the
easier i915_active -- with the plan that this avoids any potential
atomic callbacks as the frontbuffer tracking wishes to sleep as it
flushes.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190816074635.26062-1-chris@chris-wilson.co.uk

6 files changed, 10 insertions, 47 deletions

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
index c31684682eaa..77944950d4c9 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
@@ -49,7 +49,7 @@ static void __i915_do_clflush(struct drm_i915_gem_object *obj)
 {
 	GEM_BUG_ON(!i915_gem_object_has_pages(obj));
 	drm_clflush_sg(obj->mm.pages);
-	intel_fb_obj_flush(obj, ORIGIN_CPU);
+	intel_frontbuffer_flush(obj->frontbuffer, ORIGIN_CPU);
 }
 
 static void i915_clflush_work(struct work_struct *work)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_domain.c b/drivers/gpu/drm/i915/gem/i915_gem_domain.c
index 2e3ce2a69653..a1afc2690e9e 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_domain.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_domain.c
@@ -551,13 +551,6 @@ i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write)
 	return 0;
 }
 
-static inline enum fb_op_origin
-fb_write_origin(struct drm_i915_gem_object *obj, unsigned int domain)
-{
-	return (domain == I915_GEM_DOMAIN_GTT ?
-		obj->frontbuffer_ggtt_origin : ORIGIN_CPU);
-}
-
 /**
  * Called when user space prepares to use an object with the CPU, either
  * through the mmap ioctl's mapping or a GTT mapping.
@@ -661,9 +654,8 @@ i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
 
 	i915_gem_object_unlock(obj);
 
-	if (write_domain != 0)
-		intel_fb_obj_invalidate(obj,
-					fb_write_origin(obj, write_domain));
+	if (write_domain)
+		intel_frontbuffer_invalidate(obj->frontbuffer, ORIGIN_CPU);
 
 out_unpin:
 	i915_gem_object_unpin_pages(obj);
@@ -783,7 +775,7 @@ int i915_gem_object_prepare_write(struct drm_i915_gem_object *obj,
 	}
 
 out:
-	intel_fb_obj_invalidate(obj, ORIGIN_CPU);
+	intel_frontbuffer_invalidate(obj->frontbuffer, ORIGIN_CPU);
 	obj->mm.dirty = true;
 	/* return with the pages pinned */
 	return 0;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index cfaedb4b70bd..501ab55f1280 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -101,9 +101,6 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 		up_write(&mm->mmap_sem);
 		if (IS_ERR_VALUE(addr))
 			goto err;
-
-		/* This may race, but that's ok, it only gets set */
-		WRITE_ONCE(obj->frontbuffer_ggtt_origin, ORIGIN_CPU);
 	}
 	i915_gem_object_put(obj);
 
@@ -283,7 +280,6 @@ vm_fault_t i915_gem_fault(struct vm_fault *vmf)
 		 * Userspace is now writing through an untracked VMA, abandon
 		 * all hope that the hardware is able to track future writes.
 		 */
-		obj->frontbuffer_ggtt_origin = ORIGIN_CPU;
 
 		vma = i915_gem_object_ggtt_pin(obj, &view, 0, 0, flags);
 		if (IS_ERR(vma) && !view.type) {
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c
index 3929c3a6b281..0807bb5464cf 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c
@@ -46,16 +46,6 @@ void i915_gem_object_free(struct drm_i915_gem_object *obj)
 	return kmem_cache_free(global.slab_objects, obj);
 }
 
-static void
-frontbuffer_retire(struct i915_active_request *active,
-		   struct i915_request *request)
-{
-	struct drm_i915_gem_object *obj =
-		container_of(active, typeof(*obj), frontbuffer_write);
-
-	intel_fb_obj_flush(obj, ORIGIN_CS);
-}
-
 void i915_gem_object_init(struct drm_i915_gem_object *obj,
 			  const struct drm_i915_gem_object_ops *ops)
 {
@@ -72,10 +62,6 @@ void i915_gem_object_init(struct drm_i915_gem_object *obj,
 
 	obj->ops = ops;
 
-	obj->frontbuffer_ggtt_origin = ORIGIN_GTT;
-	i915_active_request_init(&obj->frontbuffer_write,
-				 NULL, frontbuffer_retire);
-
 	obj->mm.madv = I915_MADV_WILLNEED;
 	INIT_RADIX_TREE(&obj->mm.get_page.radix, GFP_KERNEL | __GFP_NOWARN);
 	mutex_init(&obj->mm.get_page.lock);
@@ -187,7 +173,6 @@ static void __i915_gem_free_objects(struct drm_i915_private *i915,
 
 		GEM_BUG_ON(atomic_read(&obj->bind_count));
 		GEM_BUG_ON(obj->userfault_count);
-		GEM_BUG_ON(atomic_read(&obj->frontbuffer_bits));
 		GEM_BUG_ON(!list_empty(&obj->lut_list));
 
 		atomic_set(&obj->mm.pages_pin_count, 0);
@@ -230,6 +215,8 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
 	struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 
+	GEM_BUG_ON(i915_gem_object_is_framebuffer(obj));
+
 	/*
 	 * Before we free the object, make sure any pure RCU-only
 	 * read-side critical sections are complete, e.g.
@@ -261,13 +248,6 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
 		queue_work(i915->wq, &i915->mm.free_work);
 }
 
-static inline enum fb_op_origin
-fb_write_origin(struct drm_i915_gem_object *obj, unsigned int domain)
-{
-	return (domain == I915_GEM_DOMAIN_GTT ?
-		obj->frontbuffer_ggtt_origin : ORIGIN_CPU);
-}
-
 static bool gpu_write_needs_clflush(struct drm_i915_gem_object *obj)
 {
 	return !(obj->cache_level == I915_CACHE_NONE ||
@@ -290,8 +270,7 @@ i915_gem_object_flush_write_domain(struct drm_i915_gem_object *obj,
 		for_each_ggtt_vma(vma, obj)
 			intel_gt_flush_ggtt_writes(vma->vm->gt);
 
-		intel_fb_obj_flush(obj,
-				   fb_write_origin(obj, I915_GEM_DOMAIN_GTT));
+		intel_frontbuffer_flush(obj->frontbuffer, ORIGIN_CPU);
 
 		for_each_ggtt_vma(vma, obj) {
 			if (vma->iomap)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index 3714cf234d64..abc23e7e13a7 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -161,7 +161,7 @@ i915_gem_object_needs_async_cancel(const struct drm_i915_gem_object *obj)
 static inline bool
 i915_gem_object_is_framebuffer(const struct drm_i915_gem_object *obj)
 {
-	return READ_ONCE(obj->framebuffer_references);
+	return READ_ONCE(obj->frontbuffer);
 }
 
 static inline unsigned int
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
index d474c6ac4100..ede0eb4218a8 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -13,6 +13,7 @@
 #include "i915_selftest.h"
 
 struct drm_i915_gem_object;
+struct intel_fronbuffer;
 
 /*
  * struct i915_lut_handle tracks the fast lookups from handle to vma used
@@ -141,9 +142,7 @@ struct drm_i915_gem_object {
 	 */
 	u16 write_domain;
 
-	atomic_t frontbuffer_bits;
-	unsigned int frontbuffer_ggtt_origin; /* write once */
-	struct i915_active_request frontbuffer_write;
+	struct intel_frontbuffer *frontbuffer;
 
 	/** Current tiling stride for the object, if it's tiled. */
 	unsigned int tiling_and_stride;
@@ -224,9 +223,6 @@ struct drm_i915_gem_object {
 		bool quirked:1;
 	} mm;
 
-	/** References from framebuffers, locks out tiling changes. */
-	unsigned int framebuffer_references;
-
 	/** Record of address bit 17 of each page at last unbind. */
 	unsigned long *bit_17;