Subject: Re: [PATCH] net-next: Fix __inet_inherit_port() to correctly increment bsockets and num_owners

From: Evgeniy Polyakov <[email-masked]>
Date: Mon, 29 Nov 2010 15:51:02 +0300

On Mon, Nov 29, 2010 at 12:39:09PM +0000, Jarek Poplawski ([email-masked]) wrote:
> >> inet sockets corresponding to passive connections are added to the bind hash
> >> using ___inet_inherit_port(). These sockets are later removed from the bind 
> >> hash using __inet_put_port(). These two functions are not exactly symmetrical. 
> >> __inet_put_port() decrements hashinfo->bsockets and tb->num_owners, whereas 
> >> ___inet_inherit_port() does not increment them. This results in both of these 
> >> going to -ve values.
> >>
> >> This patch fixes this by calling inet_bind_hash() from ___inet_inherit_port(),
> >> which does the right thing.
> >>
> >> 'bsockets' and 'num_owners' were introduced by commit a9d8f9110d7e953c 
> >> (inet: Allowing more than 64k connections and heavily optimize bind(0))
> > 
> > Yup, things changed from that simple patch a lot.
> > Thanks for fixing it up.
> > Ack.
> 
> Probably I miss something, but since bsockets is increased by each
> passive connection now, it seems it will trigger "hash table is full"
> too early?

Why would it? bsockets and num_owners are supposed to be increased for each
new socket added into the table, and are used as a hint to find a bucket with
the smallest number of sockets in it.

Hash table insertion did not change, only bucket selection algorithm got
a hint.

-- 
	Evgeniy Polyakov