drm/i915: combine all small integers into one single bitfield
This saves a whooping 7 dwords. Zero functional changes. Because
some of the refcounts are rather tightly calculated, I've put
BUG_ONs in the code to check for overflows.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 91b3a1c..cccf801 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -658,19 +658,64 @@
* (has pending rendering), and is not set if it's on inactive (ready
* to be unbound).
*/
- int active;
+ unsigned int active : 1;
/**
* This is set if the object has been written to since last bound
* to the GTT
*/
- int dirty;
+ unsigned int dirty : 1;
+
+ /**
+ * Fence register bits (if any) for this object. Will be set
+ * as needed when mapped into the GTT.
+ * Protected by dev->struct_mutex.
+ *
+ * Size: 4 bits for 16 fences + sign (for FENCE_REG_NONE)
+ */
+ int fence_reg : 5;
+
+ /**
+ * Used for checking the object doesn't appear more than once
+ * in an execbuffer object list.
+ */
+ unsigned int in_execbuffer : 1;
+
+ /**
+ * Advice: are the backing pages purgeable?
+ */
+ unsigned int madv : 2;
+
+ /**
+ * Refcount for the pages array. With the current locking scheme, there
+ * are at most two concurrent users: Binding a bo to the gtt and
+ * pwrite/pread using physical addresses. So two bits for a maximum
+ * of two users are enough.
+ */
+ unsigned int pages_refcount : 2;
+#define DRM_I915_GEM_OBJECT_MAX_PAGES_REFCOUNT 0x3
+
+ /**
+ * Current tiling mode for the object.
+ */
+ unsigned int tiling_mode : 2;
+
+ /** How many users have pinned this object in GTT space. The following
+ * users can each hold at most one reference: pwrite/pread, pin_ioctl
+ * (via user_pin_count), execbuffer (objects are not allowed multiple
+ * times for the same batchbuffer), and the framebuffer code. When
+ * switching/pageflipping, the framebuffer code has at most two buffers
+ * pinned per crtc.
+ *
+ * In the worst case this is 1 + 1 + 1 + 2*2 = 7. That would fit into 3
+ * bits with absolutely no headroom. So use 4 bits. */
+ int pin_count : 4;
+#define DRM_I915_GEM_OBJECT_MAX_PIN_COUNT 0xf
/** AGP memory structure for our GTT binding. */
DRM_AGP_MEM *agp_mem;
struct page **pages;
- int pages_refcount;
/**
* Current offset of the object in GTT space.
@@ -687,21 +732,10 @@
*/
uint64_t mmap_offset;
- /**
- * Fence register bits (if any) for this object. Will be set
- * as needed when mapped into the GTT.
- * Protected by dev->struct_mutex.
- */
- int fence_reg;
-
- /** How many users have pinned this object in GTT space */
- int pin_count;
-
/** Breadcrumb of last rendering to the buffer. */
uint32_t last_rendering_seqno;
- /** Current tiling mode for the object. */
- uint32_t tiling_mode;
+ /** Current tiling stride for the object, if it's tiled. */
uint32_t stride;
/** Record of address bit 17 of each page at last unbind. */
@@ -724,17 +758,6 @@
struct drm_i915_gem_phys_object *phys_obj;
/**
- * Used for checking the object doesn't appear more than once
- * in an execbuffer object list.
- */
- int in_execbuffer;
-
- /**
- * Advice: are the backing pages purgeable?
- */
- int madv;
-
- /**
* Number of crtcs where this object is currently the fb, but
* will be page flipped away on the next vblank. When it
* reaches 0, dev_priv->pending_flip_queue will be woken up.