Re: [PATCH net v2] switchdev: don't abort hardware ipv4 fib offload on failure to program fib entry in hardware

[Scott Feldman <sfeldma@gmail.com>]

On Sun, May 17, 2015 at 4:42 PM, Roopa Prabhu <roopa@cumulusnetworks.com> wrote:
> From: Roopa Prabhu <roopa@cumulusnetworks.com>
>
> This patch removes the calls to netdev_switch_fib_ipv4_abort when
> there is an error in programming fib entry in hardware.
>
> On most systems where you can offload routes to hardware,
> doing routing in software is not an option (the cpu limitations
> make routing impossible in software).
>
> I understand that this was added to keep the first fib offload support
> simple.
>
> As discussed in the RFC patch, available options:
> a) Fail fib entry add on hardware offload failure on switch devices, and
> return appropriate error to the user by default (this patch)
> b) make the behaviour in a) conditional on a global flag/sysctl (a per fib
> entry flag will not work because by default user/routing-daemons dont care
> if they are hardware offloaded)
> c) for users/routing-daemons interested in controlling hardware
> offload behaviour there is always the per fib entry flag RTNH_F_OFFLOAD
>
> Considering the characteristics of the systems that support fib offloads,
> this patch implements a). Also making a) the default will enable easier/faster
> migration of existing routing apps to switch devices.
>
> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>

Acked-by: Scott Feldman <sfeldma@gmail.com>