Revert "drm/amdkfd: Add memory sync before TLB flush on unmap"

This reverts commit 3be4dca1.

Reason for revert: it causes regressions on several Asics.
Signed-off-by: Eric Huang <jinhuieric.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -1566,29 +1566,13 @@ static int kfd_ioctl_unmap_memory_from_gpu(struct file *filep,
 			       i, args->n_devices);
 			goto unmap_memory_from_gpu_failed;
 		}
-		args->n_success = i+1;
-	}
-	mutex_unlock(&p->mutex);
-
-	err = amdgpu_amdkfd_gpuvm_sync_memory(dev->kgd, (struct kgd_mem *) mem, true);
-	if (err) {
-		pr_debug("Sync memory failed, wait interrupted by user signal\n");
-		goto sync_memory_failed;
-	}
-
-	/* Flush TLBs after waiting for the page table updates to complete */
-	for (i = 0; i < args->n_devices; i++) {
-		peer = kfd_device_by_id(devices_arr[i]);
-		if (WARN_ON_ONCE(!peer))
-			continue;
-		peer_pdd = kfd_get_process_device_data(peer, p);
-		if (WARN_ON_ONCE(!peer_pdd))
-			continue;
 		kfd_flush_tlb(peer_pdd, TLB_FLUSH_HEAVYWEIGHT);
+		args->n_success = i+1;
 	}
-
 	kfree(devices_arr);
 
+	mutex_unlock(&p->mutex);
+
 	return 0;
 
 bind_process_to_device_failed:
@@ -1596,7 +1580,6 @@ static int kfd_ioctl_unmap_memory_from_gpu(struct file *filep,
 unmap_memory_from_gpu_failed:
 	mutex_unlock(&p->mutex);
 copy_from_user_failed:
-sync_memory_failed:
 	kfree(devices_arr);
 	return err;
 }