  Cache side channel attacks obtain victim cache line access footprint to infer
security-critical information. Among them, cross-core attacks exploiting the
shared last level cache are more threatening as their simplicity to set up and
high capacity. Stateful approaches of detection-based mitigation observe
precise cache behaviors and protect specific cache lines that are suspected of
being attacked. However, their recording structures incur large storage
overhead and are vulnerable to reverse engineering attacks. Exploring the
intrinsic non-determinate layout of a traditional Cuckoo filter, this paper
proposes a space efficient Auto-Cuckoo filter to record access footprints,
which succeed to decrease storage overhead and resist reverse engineering
attacks at the same time. With Auto-Cuckoo filter, we propose PiPoMonitor to
detect \textit{Ping-Pong patterns} and prefetch specific cache line to
interfere with adversaries' cache probes. Security analysis shows the
PiPoMonitor can effectively mitigate cross-core attacks and the Auto-Cuckoo
filter is immune to reverse engineering attacks. Evaluation results indicate
PiPoMonitor has negligible impact on performance and the storage overhead is
only 0.37$\%$, an order of magnitude lower than previous stateful approaches.
