netdev - Re: [PATCH net-2.6.24] introduce MAC_FMT/MAC

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 27 Aug 2007 08:44:17 -0700
From:	Joe Perches <joe@...ches.com>
To:	Johannes Berg <johannes@...solutions.net>
Cc:	"David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: [PATCH net-2.6.24] introduce MAC_FMT/MAC_ARG

On Mon, 2007-08-27 at 12:54 +0200, Johannes Berg wrote:
> Thanks for this patch though, I'd have done it otherwise.

I had it, it was just a s/EUI48/MAC/ and copy/paste thing.

There are also the arch, drivers/[^net], and net directories
that have a few of these.

The patch also added the missing ")" in drivers/net/82596.c

> I was rereading your original conversion and noticed that it is now
> trivial to make the kernel smaller like you originally wanted by doing
> something like this
> 
> -- define this function somewhere --
> print_mac(u8 *mac, char *buf)
> {
> 	sprintf(buf, "%02x:...", mac[0], mac[1], ...);
> }
> EXPORT_SYMBOL(print_mac)
> 
> -- change macros to --
> #define MAC_FMT "%s"
> #define MAC_ARG(a) ({char __buf[18]; print_mac(a, buf); __buf})
> 
> I'm not sure we'd want that, but at the time you said it made the kernel
> significantly smaller and I doubt there's a performance problem with it
> (who prints mac addresses regularly?)

The reduction is ~.1% in an allyesconfig.
The compound statement to hide the automatic works well.
The function call is noise compared to the printk.

cheers, Joe

-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html