From: Pablo Neira Ayuso <pablo@netfilter.org>
To: Florian Westphal <fw@strlen.de>
Cc: netfilter-devel@vger.kernel.org
Subject: Re: [PATCH nf-next] netfilter: nft_set_rbtree: use seqcount to avoid lock in most cases
Date: Wed, 26 Jul 2017 13:25:07 +0200 [thread overview]
Message-ID: <20170726112507.GA2217@salvia> (raw)
In-Reply-To: <20170726111506.GA1816@salvia>
On Wed, Jul 26, 2017 at 01:15:06PM +0200, Pablo Neira Ayuso wrote:
> On Wed, Jul 26, 2017 at 02:09:41AM +0200, Florian Westphal wrote:
> [...]
> > @@ -144,7 +159,9 @@ static int nft_rbtree_insert(const struct net *net, const struct nft_set *set,
> > int err;
> >
> > write_lock_bh(&priv->lock);
> > + write_seqcount_begin(&priv->count);
> > err = __nft_rbtree_insert(net, set, rbe, ext);
> > + write_seqcount_end(&priv->count);
> > write_unlock_bh(&priv->lock);
> >
> > return err;
> > @@ -158,7 +175,9 @@ static void nft_rbtree_remove(const struct net *net,
> > struct nft_rbtree_elem *rbe = elem->priv;
> >
> > write_lock_bh(&priv->lock);
>
> Do we need the spinlock anymore? This is protected by mutex from
> userspace, and we have no support for neither timeouts nor dynamic set
> population from packet path yet.
Forget this, I overlook we have a slow path in case seq mismatches.
prev parent reply other threads:[~2017-07-26 11:25 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-26 0:09 [PATCH nf-next] netfilter: nft_set_rbtree: use seqcount to avoid lock in most cases Florian Westphal
2017-07-26 10:34 ` Eric Dumazet
2017-07-26 11:04 ` Florian Westphal
2017-07-26 11:15 ` Pablo Neira Ayuso
2017-07-26 11:25 ` Pablo Neira Ayuso [this message]
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