Remote function calls
This function schedules a function call on a target CPU. It is
semantically equivalent to the regular smp_call_function_single()
routine, except that its runs the callback on the out-of-band stage
with hard irqs off.
The target CPU number to run the callback function on, which must be
fast and non-blocking. The current CPU may issue a function call to
itself, in which case func is executed before this call
returns. Otherwise, the CALL_FUNCTION_OOB_IPI interrupt is
immediately sent to that CPU to notify it about the pending job.
The callback function which should run on the target CPU. This callback receives the info pointer as its sole argument.
An opaque pointer to pass to the function.
If true, wait until the function has completed on the target CPU.
This call may be invoked either from the in-band or out-of-band stages.
