Re: [dpdk-dev] [PATCH] eal: add function to check if primary proc alive

["Van Haaren, Harry" <harry.van.haaren@intel.com>]

> From: Qiu, Michael
> > Whatever work the secondary was performing (in its own address space)
> > won't be directly changed by the primary being killed, because the
> > shared config and hugepages stay (EAL "cleans up" when the primary
> > is re-launched, not on quit).
> 
> OK,  when primary quit or be killed, the queues will be freed, it will
> be a potential issue when secondary try to access, maybe I'm wrong.

The use-case for this patch is monitoring statistics and fault-detection.
That involves reading registers directly from the NIC, and the NIC
rx/tx queues are not used. I think you are right that using the rx/tx
queues from a secondary process when they have been cleaned-up by the
primary process will indeed cause issues.

If there is a valid use-case where both primary and secondary processes
will be forwarding packets on the same NIC, this issue should be discussed
in more detail.

In its current state, this patch solves a problem for the use case of a
primary process forwarding packets, and a secondary process monitoring
and providing fault-detection.

-Harry