@@ -172,7 +172,7 @@ static int radeon_cs_parser_relocs(struct radeon_cs_parser *p)
radeon_cs_buckets_get_list(&buckets, &p->validated);
- return radeon_bo_list_validate(&p->ticket, &p->validated, p->ring);
+ return radeon_bo_list_validate(p->rdev, &p->ticket, &p->validated, p->ring);
}
static int radeon_cs_get_ring(struct radeon_cs_parser *p, u32 ring, s32 priority)
@@ -368,29 +368,104 @@ void radeon_bo_fini(struct radeon_device *rdev)
arch_phys_wc_del(rdev->mc.vram_mtrr);
}
-int radeon_bo_list_validate(struct ww_acquire_ctx *ticket,
+/* Returns how many bytes TTM can move per IB.
+ */
+static u64 radeon_bo_get_threshold_for_moves(struct radeon_device *rdev)
+{
+ u64 real_vram_size = rdev->mc.real_vram_size;
+ u64 vram_usage = &rdev->vram_usage;
+
+ /* This function is based on the current VRAM usage.
+ *
+ * - If all of VRAM is free, allow relocating the number of bytes that
+ * is equal to 1/4 of the size of VRAM for this IB.
+
+ * - If more than one half of VRAM is occupied, only allow relocating
+ * 1 MB of data for this IB.
+ *
+ * - From 0 to one half of used VRAM, the threshold decreases
+ * linearly.
+ * __________________
+ * 1/4 of -|\ |
+ * VRAM | \ |
+ * | \ |
+ * | \ |
+ * | \ |
+ * | \ |
+ * | \ |
+ * | \________|1 MB
+ * |----------------|
+ * VRAM 0 % 100 %
+ * used used
+ *
+ * Note: It's a threshold, not a limit. The threshold must be crossed
+ * for buffer relocations to stop, so any buffer of an arbitrary size
+ * can be moved as long as the threshold isn't crossed before
+ * the relocation takes place. We don't want to disable buffer
+ * relocations completely.
+ *
+ * The idea is that buffers should be placed in VRAM at creation time
+ * and TTM should only do a minimum number of relocations during
+ * command submission. In practice, you need to submit at least
+ * a dozen IBs to move all buffers to VRAM if they are in GTT.
+ *
+ * Also, things can get pretty crazy under memory pressure and actual
+ * VRAM usage can change a lot, so playing safe even at 50% does
+ * consistently increase performance.
+ */
+
+ u64 half_vram = real_vram_size >> 1;
+ u64 half_free_vram = vram_usage >= half_vram ? 0 : half_vram - vram_usage;
+ u64 bytes_moved_threshold = half_free_vram >> 1;
+ return max(bytes_moved_threshold, 1024*1024ull);
+}
+
+int radeon_bo_list_validate(struct radeon_device *rdev,
+ struct ww_acquire_ctx *ticket,
struct list_head *head, int ring)
{
struct radeon_bo_list *lobj;
struct radeon_bo *bo;
- u32 domain;
int r;
+ u64 bytes_moved = 0, initial_bytes_moved;
+ u64 bytes_moved_threshold = radeon_bo_get_threshold_for_moves(rdev);
r = ttm_eu_reserve_buffers(ticket, head);
if (unlikely(r != 0)) {
return r;
}
+
list_for_each_entry(lobj, head, tv.head) {
bo = lobj->bo;
if (!bo->pin_count) {
- domain = lobj->domain;
-
+ u32 domain = lobj->domain;
+ u32 current_domain =
+ radeon_mem_type_to_domain(bo->tbo.mem.mem_type);
+
+ /* Check if this buffer will be moved and don't move it
+ * if we have moved too many buffers for this IB already.
+ *
+ * Note that this allows moving at least one buffer of
+ * any size, because it doesn't take the current "bo"
+ * into account. We don't want to disallow buffer moves
+ * completely.
+ */
+ if (current_domain != RADEON_GEM_DOMAIN_CPU &&
+ (domain & current_domain) == 0 && /* will be moved */
+ bytes_moved > bytes_moved_threshold) {
+ /* don't move it */
+ domain = current_domain;
+ }
+
retry:
radeon_ttm_placement_from_domain(bo, domain);
if (ring == R600_RING_TYPE_UVD_INDEX)
radeon_uvd_force_into_uvd_segment(bo);
- r = ttm_bo_validate(&bo->tbo, &bo->placement,
- true, false);
+
+ initial_bytes_moved = rdev->num_bytes_moved;
+ r = ttm_bo_validate(&bo->tbo, &bo->placement, true, false);
+ bytes_moved += rdev->num_bytes_moved - initial_bytes_moved;
+
if (unlikely(r)) {
if (r != -ERESTARTSYS && domain != lobj->alt_domain) {
domain = lobj->alt_domain;
@@ -138,7 +138,8 @@ extern int radeon_bo_evict_vram(struct radeon_device *rdev);
extern void radeon_bo_force_delete(struct radeon_device *rdev);
extern int radeon_bo_init(struct radeon_device *rdev);
extern void radeon_bo_fini(struct radeon_device *rdev);
-extern int radeon_bo_list_validate(struct ww_acquire_ctx *ticket,
+extern int radeon_bo_list_validate(struct radeon_device *rdev,
+ struct ww_acquire_ctx *ticket,
struct list_head *head, int ring);
extern int radeon_bo_fbdev_mmap(struct radeon_bo *bo,
struct vm_area_struct *vma);