p4wq: fix races when handling work items
Work items in P4WQ currently belong to the user before submission
and after exit from the handler, therefore, unless the handler
re-submits the item, accessing it in p4wq_loop() in such cases
is racy. To fix this we re-define work item ownership. Now the
item belongs to the P4WQ core until the user calls
k_p4wq_wait(). If the work item has its .sync flag set, the
function will sleep until the handler completes processing the
work item or until the timeout expires. If .sync isn't set and
the handler hasn't processed the item yet, the function returns
-EBUSY.
Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
2 files changed