I just use API call to get the stock created or updated. code is following:
$access_token = '4v81lfihtkqanfdr6798zj352qyuyx1x';
$url = 'http://magento2.local/index.php/rest/V1/inventory/source-items';
$ch = curl_init($url);
$body = json_encode(['sourceItems' =>[
['source_code' => 'default', 'sku' => '24-MB01', 'quantity'=>555, 'status'=>1],
['source_code' => 'la', 'sku' => '24-MB01', 'quantity' => 222, 'status' => 1],
['source_code' => 'default', 'sku' => '24-MB04', 'quantity'=>444, 'status'=>1],
['source_code' => 'la', 'sku' => '24-MB04', 'quantity' => 111, 'status' => 1],
['source_code' => 'default', 'sku' => '24-MB03', 'quantity'=>333, 'status'=>1],
['source_code' => 'la', 'sku' => '24-MB03', 'quantity' => 111, 'status' => 1],
]]);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $body);
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json', 'Authorization: Bearer ' . $access_token));
$result = curl_exec($ch);
var_dump($result);