[Nouveau] [PATCH] nouveau: find the smallest page allocation to cover a buffer alloc.

[Dave Airlie <airlied@gmail.com>]

From: Dave Airlie <airlied@redhat.com>

With the new uapi we don't have the comp flags on the allocation,
so we shouldn't be using the first size that works, we should be
iterating until we get the correct one.

This reduces allocations from 2MB to 64k in lots of places.

Fixes dEQP-VK.memory.allocation.basic.size_8KiB.forward.count_4000
on my ampere/gsp system.

Signed-off-by: Dave Airlie <airlied@redhat.com>
---
 drivers/gpu/drm/nouveau/nouveau_bo.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
index 949195d5d782..a6993c7807b6 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -318,8 +318,9 @@ nouveau_bo_alloc(struct nouveau_cli *cli, u64 *size, int *align, u32 domain,
 			    (!vmm->page[i].host || vmm->page[i].shift > PAGE_SHIFT))
 				continue;
 
-			if (pi < 0)
-				pi = i;
+			/* pick the last one as it will be smallest. */
+			pi = i;
+
 			/* Stop once the buffer is larger than the current page size. */
 			if (*size >= 1ULL << vmm->page[i].shift)
 				break;
-- 
2.41.0