pktgen issue with "Observe needed_headroom of the device"

Regarding this commit:

879c7220e828af8bd82ea9d774c7e45c46b976e4

net: pktgen: Observe needed_headroom of the device

Allocate enough space so as not to force the outgoing net device to do skb_realloc_headroom().

I think it may be incorrect. It seems that pkt_overhead is meant to be the data-portion of the skb, not lower-level padding?

For instance:

int pkt_overhead; /* overhead for MPLS, VLANs, IPSEC etc */
...

	/* Eth + IPh + UDPh + mpls */
	datalen = pkt_dev->cur_pkt_size - 14 - 20 - 8 -
		  pkt_dev->pkt_overhead;

So, maybe we need to add that LL_RESERVED_SPACE to the size when allocating the skb in pktgen_alloc_skb and leave it out of pkt_overhead?

And for that matter, what is that '+ 64 +' for in the size calculation? Looks a lot like some fudge factor from long ago?

Thanks,
Ben

Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com