give one's all

"I'd go myself, if I was any use. As I ain't, I give my boys, and give 'em free." He spoke so cheerfully, looked so sincere, and seemed so glad to give his all, that I was ashamed of myself.

The Cemeterial Division . . . has taken up the huge task of establishing contact with the mothers or widows of the 30,000 American soldiers who gave their all and whose bodies rest in graves across the sea.