On Wed, Mar 08, 2017 at 11:54:02AM -0500, Neil Horman wrote:

On Wed, Mar 08, 2017 at 04:15:33PM +0100, Gaetan Rivet wrote:

quoted

This PMD intercepts and manages Ethernet device removal events issued by
slave PMDs and re-initializes them transparently when brought back so that
existing applications do not need to be modified to benefit from true
hot-plugging support.

The stacked PMD approach shares many similarities with the bonding PMD but
with a different purpose. While bonding provides the ability to group
several links into a single logical device for enhanced throughput and
supports fail-over at link level, this one manages the sudden disappearance
of the underlying device; it guarantees applications face a valid device in
working order at all times.

Why not just add this feature to the bonding pmd then?  A bond is perfectly
capable of handling the trivial case of a single underlying device, and adding
an option to make the underly slave 'persistent' seem both much simpler in terms
of implementation and code size, than adding an entire new pmd, along with its
supporting code.

Neil

+1 
I don't like the idea of having multiple PMDs in DPDK to handle
combining multiple other devices into one.

/Bruce