On Tue, 2007-09-18 at 17:42 -0400, Michael Wu wrote:
> + } else if ((*total_flags & FIF_ALLMULTI) || (mc_count > 32)) {
Why the > 32 btw? The other branch below:
> + } else {
> + priv->nar &= ~(ADM8211_NAR_MM | ADM8211_NAR_PR);
> + mc_filter[1] = mc_filter[0] = 0;
> + for (i = 0; i < mc_count; i++) {
> + if (!mclist)
> + break;
> + bit_nr = ether_crc(ETH_ALEN, mclist->dmi_addr) >> 26;
> +
> + bit_nr &= 0x3F;
> + mc_filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
> + mclist = mclist->next;
> + }
looks like it's a simple hashing algorithm to filter for the multicast
address, so any number of addresses should be ok as far as I can tell,
you just see all multicast frames in a given class of the 64 classes you
have. And if many of the >32 addresses hash to the same value, it might
still be advantageous to use the filter.
johannes
Attachment:
signature.asc
Description: This is a digitally signed message part
