drm/amdgpu: add debugfs for kfd system and ttm mem used

This keeps track of kfd system mem used and kfd ttm mem used.

Signed-off-by: Alex Sierra <[e-mail]>
Reviewed-by: Philip Yang <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h

···
 struct amdgpu_amdkfd_fence *amdgpu_amdkfd_fence_create(u64 context,
 				struct mm_struct *mm,
 				struct svm_range_bo *svm_bo);
+#if defined(CONFIG_DEBUG_FS)
+int kfd_debugfs_kfd_mem_limits(struct seq_file *m, void *data);
+#endif
 #if IS_ENABLED(CONFIG_HSA_AMD)
 bool amdkfd_fence_check_mm(struct dma_fence *f, struct mm_struct *mm);
 struct amdgpu_amdkfd_fence *to_amdgpu_amdkfd_fence(struct dma_fence *f);

drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c

···
 	}
 	return false;
 }
+
+#if defined(CONFIG_DEBUG_FS)
+
+int kfd_debugfs_kfd_mem_limits(struct seq_file *m, void *data)
+{
+
+	spin_lock(&kfd_mem_limit.mem_limit_lock);
+	seq_printf(m, "System mem used %lldM out of %lluM\n",
+		  (kfd_mem_limit.system_mem_used >> 20),
+		  (kfd_mem_limit.max_system_mem_limit >> 20));
+	seq_printf(m, "TTM mem used %lldM out of %lluM\n",
+		  (kfd_mem_limit.ttm_mem_used >> 20),
+		  (kfd_mem_limit.max_ttm_mem_limit >> 20));
+	spin_unlock(&kfd_mem_limit.mem_limit_lock);
+
+	return 0;
+}
+
+#endif

drivers/gpu/drm/amd/amdkfd/kfd_debugfs.c

···
 			    kfd_debugfs_rls_by_device, &kfd_debugfs_fops);
 	debugfs_create_file("hang_hws", S_IFREG | 0200, debugfs_root,
 			    kfd_debugfs_hang_hws_read, &kfd_debugfs_hang_hws_fops);
+	debugfs_create_file("mem_limit", S_IFREG | 0200, debugfs_root,
+			    kfd_debugfs_kfd_mem_limits, &kfd_debugfs_fops);
 }
 
 void kfd_debugfs_fini(void)