Re: [patch] block layer: kmemcheck fixes

David Miller
2008-02-08T01:22:25Z

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Thu, 7 Feb 2008 09:42:56 -0800 (PST)

> Can we please just stop doing these one-by-one assignments, and just do
> something like
>
> memset(rq, 0, sizeof(*rq));
> rq->q = q;
> rq->ref_count = 1;
> INIT_HLIST_NODE(&rq->hash);
> RB_CLEAR_NODE(&rq->rb_node);
>
> instead?
>
> The memset() is likely faster and smaller than one-by-one assignments
> anyway, even if the one-by-ones can avoid initializing some field or there
> ends up being a double initialization..

The problem is store buffer compression. At least a few years
ago this made a huge difference in sk_buff initialization in the
networking.

Maybe cpus these days have so much store bandwith that doing
things like the above is OK, but I doubt it :-)