On Thu, 2006-29-06 at 17:12 -0700, David Miller wrote:

From: jamal <redacted>
Date: Thu, 29 Jun 2006 20:08:19 -0400

quoted

What am i missing?
on 64bit machine, does it not save 32 bits to use an ifindex as opposed
to the pointer?

The objects around it are pointers, which are 64-bit, and thus
the 32-bit object gets padded out to 64-bits in the layout of
the struct so that the next pointer member can be properly
aligned.

It does not change the size of sk_buff at all.

I see; i take it if things were moved around that may change?

quoted

Yes, it is a bug, but:
dev_hold/put dont work anymore? why do you need an ifindex instead?

You sure you want to do that atomic operation on every single
input packet, regardless of whether egress operations are
using it or not?

Can you avoid doing the refcount?
Note Thomas is doing dev_get_by_index (which will do the atomic ref
count).

For me the choice is between having the iif and:
- __get device from ifindex
- reference dev->something

vs getting the input_dev and
- reference dev->something

We should put the cost of features at the actual users, and not
impose it upon everyone.

I didnt quiet follow, the ref count seems only needed in the
redirection, no?

cheers,
jamal