From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Oeser <netdev@axxeo.de>
Subject: Re: [PATCH net-2.6.25 3/3] Uninline the inet_twsk_put function
Date: Thu, 20 Dec 2007 19:32:45 +0100
Message-ID: <200712201932.45900.netdev@axxeo.de>
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Cc: David Miller <davem@davemloft.net>,
	Linux Netdev List <netdev@vger.kernel.org>, devel@openvz.org
To: Pavel Emelyanov <xemul@openvz.org>
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Pavel Emelyanov schrieb:
> This one is not that big, but is widely used: saves 1200 bytes 
> from net/ipv4/built-in.o
> +void inet_twsk_put(struct inet_timewait_sock *tw)
> +{
> +	if (atomic_dec_and_test(&tw->tw_refcnt)) {
> +		struct module *owner = tw->tw_prot->owner;
> +		twsk_destructor((struct sock *)tw);
> +#ifdef SOCK_REFCNT_DEBUG
> +		printk(KERN_DEBUG "%s timewait_sock %p released\n",
> +		       tw->tw_prot->name, tw);
> +#endif
> +		kmem_cache_free(tw->tw_prot->twsk_prot->twsk_slab, tw);
> +		module_put(owner);
> +	}
> +}
> +EXPORT_SYMBOL_GPL(inet_twsk_put);

More correct fix seems to be conversion to kref.

Just create out of line inet_twsk_release() containing
sth. similiar to the code inside these braces and modify 
inet_twsk_put() to sth. like this:

static inline inet_twsk_put(struct inet_timewait_sock *tw)
{
	kref_put(&tw->kref, inet_twsk_release);
}

David, can you see any reason (e.g. some crazy lock stuff) NOT to do this?


Best Regards

Ingo Oeser