waitq - list tasks queued on a wait queue
waitq [ symbol ] | [ struct.member struct_addr ] | [ address ]
This command walks the wait queue list displaying the tasks which
are blocked on the specified wait queue. The command differentiates
between the old- and new-style wait queue structures used by the kernel.
It can be invoked with the following argument types:
symbol a global symbol of a wait queue.
struct.member struct_addr a structure name and wait queue member combination
followed by the structure's hexadecimal address.
address a hexadecimal wait queue pointer.
Find out if any tasks are blocked on the "buffer_wait" wait queue:
crash> waitq buffer_wait
wait queue "buffer_wait" (c02927f0) is empty
See who is blocked on the "wait_chldexit" queue of task c5496000:
crash> waitq task_struct.wait_chldexit c5496000
PID: 30879 TASK: c5496000 CPU: 0 COMMAND: "bash"
Display the task list waiting on a known task queue:
crash> waitq c3534098
PID: 13691 TASK: c3534000 CPU: 1 COMMAND: "bash"