getLockGuard relies on copy elision to work correctly, which the compiler
is not required to do (only with C++17).
If no copy elision happens, the mutex ends up being unlocked twice, and the
CS is executed with the mutex unlocked.
The patch also ensures that the same pattern cannot be used again.
This could happen in the following cases:
- IRQ/publisher rate is faster than the processing rate, and therefore
WorkQueue::Add is called at a higher rate
- a long-running or stuck task that blocks the work queue a long time
Both cases are not expected to happen under 'normal' circumstances (if the
system runs as expected).
* adds a work_queue systemcmd that will bring a tree view of all active work queues and work items
* WorkQueues now track attached WorkItems and will shutdown when the last WorkItem is detached
Script to update include paths:
for i in $(grep -rl 'include <px4_work_queue' src platforms); do sed -i 's/#include <px4_work_queue/#include <px4_platform_common\/px4_work_queue/' $i; done
Beat Küng