static void ath_send_bar(struct ath_atx_tid *tid, u16 seqno)
{
	if (!tid->an->sta)
		return;

	ieee80211_send_bar(tid->an->vif, tid->an->sta->addr, tid->tidno,
			   seqno << IEEE80211_SEQ_SEQ_SHIFT);
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.