1Monitor stall 2============= 3 4- Name: stall - stalled task monitor 5- Type: per-task hybrid automaton 6- Author: Gabriele Monaco <gmonaco@redhat.com> 7 8Description 9----------- 10 11The stalled task (stall) monitor is a sample per-task timed monitor that checks 12if tasks are scheduled within a defined threshold after they are ready:: 13 14 | 15 | 16 v 17 #==========================# 18 +-----------------> H dequeued H 19 | #==========================# 20 | | 21 sched_switch_wait | sched_wakeup;reset(clk) 22 | v 23 | +--------------------------+ <+ 24 | | enqueued | | sched_wakeup 25 | | clk < threshold_jiffies | -+ 26 | +--------------------------+ 27 | | ^ 28 | sched_switch_in sched_switch_preempt;reset(clk) 29 | v | 30 | +--------------------------+ 31 +------------------ | running | 32 +--------------------------+ 33 ^ sched_switch_in | 34 | sched_wakeup | 35 +----------------------+ 36 37The threshold can be configured as a parameter by either booting with the 38``stall.threshold_jiffies=<new value>`` argument or writing a new value to 39``/sys/module/stall/parameters/threshold_jiffies``. 40 41Specification 42------------- 43Graphviz Dot file in tools/verification/models/stall.dot 44