defer cancel()
	cc.vlogf("http2: Transport sending health check")
	err := cc.Ping(ctx)
	if err != nil {
		cc.vlogf("http2: Transport health check failure: %v", err)
		cc.closeForLostPing()
	} else {
		cc.vlogf("http2: Transport health check success")
	}
}

// SetDoNotReuse marks cc as not reusable for future HTTP requests.
func (cc *http2ClientConn) SetDoNotReuse() {