[PATCH] drm/amdgpu: fix user queue wait ioctl fence counting

[Jesse Zhang]

The original change "drm/amdgpu: promote the implicit sync to the dependent read fences"
(commit 714bbbf20a72) modified fence synchronization to use DMA_RESV_USAGE_READ
instead of DMA_RESV_USAGE_BOOKKEEP. However, the user queue wait ioctl wasn't fully
updated to account for this change, leading to potential synchronization issues.

This commit fixes the fence counting logic to properly account for both:
1. READ/WRITE fences (for normal synchronization)
2. BOOKKEEP fences (for eviction synchronization)

The change ensures:
- All relevant fences are properly counted before allocation

Fixes: 714bbbf20a72 ("drm/amdgpu: promote the implicit sync to the dependent read fences")

Signed-off-by: Jesse Zhang <Jesse.Zhang at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
index 029cb24c28b3..8c754474882f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
@@ -735,10 +735,18 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data,
 		for (i = 0; i < num_read_bo_handles; i++) {
 			struct dma_resv_iter resv_cursor;
 			struct dma_fence *fence;
-
+			/*
+			 * We must count both READ/WRITE and BOOKKEEP fences since:
+			 * - BOOKKEEP fences are used for eviction synchronization
+			 * - The wait operation needs to synchronize with all fence types
+			 */
 			dma_resv_for_each_fence(&resv_cursor, gobj_read[i]->resv,
 						DMA_RESV_USAGE_READ, fence)
 				num_fences++;
+
+			dma_resv_for_each_fence(&resv_cursor, gobj_read[i]->resv,
+						DMA_RESV_USAGE_BOOKKEEP, fence)
+				num_fences++;
 		}
 
 		for (i = 0; i < num_write_bo_handles; i++) {
@@ -748,6 +756,10 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data,
 			dma_resv_for_each_fence(&resv_cursor, gobj_write[i]->resv,
 						DMA_RESV_USAGE_WRITE, fence)
 				num_fences++;
+
+			dma_resv_for_each_fence(&resv_cursor, gobj_write[i]->resv,
+						DMA_RESV_USAGE_BOOKKEEP, fence)
+				num_fences++;
 		}
 
 		/*
-- 
2.34.1