Re: [patch 00/41] cpu alloc / cpu ops v3: Optimize per cpu access

Eric Dumazet
2008-05-30T10:28:57Z

Andrew Morton a écrit :
>
> It was just an example. There will be others.
>
> tcp_v4_md5_do_add
> ->tcp_alloc_md5sig_pool
> ->__tcp_alloc_md5sig_pool
>
> does an alloc_percpu for each md5-capable TCP connection. I think - it
> doesn't matter really, because something _could_. And if something
> _does_, we're screwed.
>
Last time I took a look on this stuff, this was a percpu allocation for
all connections, not for each TCP session.
(It should be static, instead of dynamic )

Really, percpu allocations are currently not frequent at all.

vmalloc()/vfreee() are way more frequent and still use a list.