Merge tag 'drm-next-2019-12-06' of git://anongit.freedesktop.org/drm/drm

[mirror_ubuntu-jammy-kernel.git] / drivers / gpu / drm / amd / amdgpu / amdgpu_amdkfd_gpuvm.c

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index 7d35b5b662290472d839707fec37df0aae5c859b..888209eb8cecd5b27b7ca68331f38364cd18d2f1 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -105,11 +105,24 @@ void amdgpu_amdkfd_gpuvm_init_mem_limits(void)
                (kfd_mem_limit.max_ttm_mem_limit >> 20));
 }
 
+/* Estimate page table size needed to represent a given memory size
+ *
+ * With 4KB pages, we need one 8 byte PTE for each 4KB of memory
+ * (factor 512, >> 9). With 2MB pages, we need one 8 byte PTE for 2MB
+ * of memory (factor 256K, >> 18). ROCm user mode tries to optimize
+ * for 2MB pages for TLB efficiency. However, small allocations and
+ * fragmented system memory still need some 4KB pages. We choose a
+ * compromise that should work in most cases without reserving too
+ * much memory for page tables unnecessarily (factor 16K, >> 14).
+ */
+#define ESTIMATE_PT_SIZE(mem_size) ((mem_size) >> 14)
+
 static int amdgpu_amdkfd_reserve_mem_limit(struct amdgpu_device *adev,
                uint64_t size, u32 domain, bool sg)
 {
+       uint64_t reserved_for_pt =
+               ESTIMATE_PT_SIZE(amdgpu_amdkfd_total_mem_size);
        size_t acc_size, system_mem_needed, ttm_mem_needed, vram_needed;
-       uint64_t reserved_for_pt = amdgpu_amdkfd_total_mem_size >> 9;
        int ret = 0;
 
        acc_size = ttm_bo_dma_acc_size(&adev->mman.bdev, size,