drm/amdgpu: Pessimistic availability based on rounded up allocations

Separately accumulate a statistic of rounded up allocations to use
to report availability, with a view to increasing the likelihood a
buffer object can be successfully allocated at exactly the size
reported by the availability API.

Signed-off-by: Daniel Phillips <daniel.phillips@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h
index 3c09dcc..647220a 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h
@@ -96,6 +96,7 @@ struct amdgpu_amdkfd_fence {
 struct amdgpu_kfd_dev {
        struct kfd_dev *dev;
        uint64_t vram_used;
+       uint64_t vram_used_aligned;
        bool init_complete;
        struct work_struct reset_work;
 };

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index 2d2ef63..cbd593f 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -182,8 +182,10 @@ int amdgpu_amdkfd_reserve_mem_limit(struct amdgpu_device *adev,
         */
        WARN_ONCE(vram_needed && !adev,
                  "adev reference can't be null when vram is used");
-       if (adev)
+       if (adev) {
                adev->kfd.vram_used += vram_needed;
+               adev->kfd.vram_used_aligned += ALIGN(vram_needed, VRAM_AVAILABLITY_ALIGN);
+       }
        kfd_mem_limit.system_mem_used += system_mem_needed;
        kfd_mem_limit.ttm_mem_used += ttm_mem_needed;
 
@@ -203,8 +205,10 @@ void amdgpu_amdkfd_unreserve_mem_limit(struct amdgpu_device *adev,
        } else if (alloc_flag & KFD_IOC_ALLOC_MEM_FLAGS_VRAM) {
                WARN_ONCE(!adev,
                          "adev reference can't be null when alloc mem flags vram is set");
-               if (adev)
+               if (adev) {
                        adev->kfd.vram_used -= size;
+                       adev->kfd.vram_used_aligned -= ALIGN(size, VRAM_AVAILABLITY_ALIGN);
+               }
        } else if (alloc_flag & KFD_IOC_ALLOC_MEM_FLAGS_USERPTR) {
                kfd_mem_limit.system_mem_used -= size;
        } else if (!(alloc_flag &
@@ -1610,7 +1614,7 @@ size_t amdgpu_amdkfd_get_available_memory(struct amdgpu_device *adev)
        size_t available;
        spin_lock(&kfd_mem_limit.mem_limit_lock);
        available = adev->gmc.real_vram_size
-               - adev->kfd.vram_used
+               - adev->kfd.vram_used_aligned
                - atomic64_read(&adev->vram_pin_size)
                - reserved_for_pt;
        spin_unlock(&kfd_mem_limit.mem_limit_lock);