DOKK / manpages / debian 10 / systemtap-doc / probe::ioscheduler_trace.unplug_io.3stap.en
PROBE::IOSCHEDULER_T(3stap) IO Scheduler and block IO Taps PROBE::IOSCHEDULER_T(3stap)

probe::ioscheduler_trace.unplug_io - Fires when a request queue is unplugged;

ioscheduler_trace.unplug_io 

rq_queue

request queue

name

Name of the probe point

Either, when number of pending requests in the queue exceeds threshold or, upon expiration of timer that was activated when queue was plugged.

tapset::ioscheduler(3stap)

October 2018 SystemTap Tapset Reference