From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [PATCH nf-next] netfilter: meta: add PRANDOM support
Date: Tue, 16 Feb 2016 14:56:23 +0100
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References: <1455624554-16005-1-git-send-email-fw@strlen.de> <56C31ABA.1050801@iogearbox.net> <20160216131910.GC13417@breakpoint.cc>
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Cc: netfilter-devel@vger.kernel.org
To: Florian Westphal <fw@strlen.de>
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On 02/16/2016 02:19 PM, Florian Westphal wrote:
> Daniel Borkmann <daniel@iogearbox.net> wrote:
>>> +	case NFT_META_PRANDOM:
>>> +		if (!prand_inited) {
>>> +			prandom_seed_full_state(&nft_prandom_state);
>>> +			prand_inited = true;
>>> +		}
>>
>> Should this be: prandom_init_once() ?
>
> Thought about that but this is slowpath so I considered
> the use of static key magic a bit overkill....
>
> I don't mind, if you think prandom_init_once is prefereable I'll respin.

You'd have the benefit that the prng init would be race free. nft_meta_get_init()
could be called in parallel from multiple CPUs, right?

> Let me know, thanks!