17.9.3.1. Workqueue from workqueue
Count from 0 to 9 every second infinitely many times by scheduling a new work item from a work item:
insmod work_from_work.ko
Stop:
rmmod work_from_work
The sleep is done indirectly through: queue_delayed_work, which waits the specified time before scheduling the work.
Source: kernel_modules/work_from_work.c