Today’s safety-critical Cyber-Physical Systems (CPS) often need to integrate multiple diverse applications with varying levels of importance, or criticality. Mixed-criticality scheduling (MCS) has been proposed with the objectives of achieving certification at multiple criticality levels and efficient utilization of hardware resources. Current work on MCS typically assumes tasks at different criticality levels are independent and do not share any resources (data). We propose highest-locker criticality, priority-ceiling protocol (HLC-PCP), which extends the well-known priority ceiling protocol (PCP) to be applicable to adaptive mixed-criticality (AMC), a variant of MCS. We present methods for worst-case blocking time computation with HLC-PCP, used for schedulability analysis of AMC with resource sharing.