From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.netfilter.org (mail.netfilter.org [217.70.190.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3FA531CB501 for ; Wed, 12 Mar 2025 16:54:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.190.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741798491; cv=none; b=ZT8ibPUcv8xgMhe9d6VKvKfmrPWPCGV5JraRRQw9m04guzc3vhZGbUDZHMQt0GbCy+MN0iFTUWPkzaWQ8a4kXmNFl2bsumxixG9iCbFm8V+wLuC47ns1dE811BayG2AMTmeND/bUw0WTIvzJMCUMJ9UEHeUQg6TBtchNBqvPIBw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741798491; c=relaxed/simple; bh=vZSyateFS+e1iETeIRpV7aKf0KTIhiP/2jQE6F7KEsQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rRC5g2I/LjeKt+ipuOi53YcvRXVEgwyTWJ05a8FD5oClzjvqqo8X3Z09z1dfhPiQwf/cv8ekptQnmpwlcZktLgK2HZYam76BmqGmdGR0DJqjK7LSlEOd1NL5yy1z1Pc6z/k5K6M0oYu0JuCV9iZ/7pwAXzlvgirPeUUvIofxwxg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org; spf=pass smtp.mailfrom=netfilter.org; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.b=MzQaqE2V; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.b=mptvZDfh; arc=none smtp.client-ip=217.70.190.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=netfilter.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.b="MzQaqE2V"; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.b="mptvZDfh" Received: by mail.netfilter.org (Postfix, from userid 109) id 5185D60293; Wed, 12 Mar 2025 17:54:41 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netfilter.org; s=2025; t=1741798481; bh=KZ5JqLSA+kDM/cREBJHbv3iNGijVSKgjHqGJ36VpQNc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MzQaqE2V802RAr75cHQbb7HMGegppL1n5d2rTYLa/DpPyVMDRlcnrX49qFIzIQemL 0RXGRT6tBkZ9toT0IC4jYuMOhL96Kdh6b+B4wyXe1xrfrvQQn47hav+AuHBQ7XqpsA CCKIdhq3ng67dPQZyV0QZytgnrL8y6mMfn/5dd4du/nluR9FWLhO8VM/MmViAozj0H +98rJ2oRVYPMNXEBZ1tJR0TXXxHmUz7JNJUt5n/Zpfwbt0izW/tGq8JayMN7DQZiA4 vW22X/Dt0tKxdymVrnOn8//jNEWc+wuoyiyV186mK/NSjTR60hnPp+XlHaAHnRX4JM 9tkEsXtarNenw== X-Spam-Level: Received: from netfilter.org (mail-agni [217.70.190.124]) by mail.netfilter.org (Postfix) with ESMTPSA id 728B560293; Wed, 12 Mar 2025 17:54:40 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netfilter.org; s=2025; t=1741798480; bh=KZ5JqLSA+kDM/cREBJHbv3iNGijVSKgjHqGJ36VpQNc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mptvZDfhSNV4Hh0aRB1sjYzxFCxQlMvm2GkGseXcZESql8j+RtdYxn5ha7mtYekHB 3FEPqllHXL/lmaD6XQ3cGd5l+8J8v2GvbrJgtarkkSzYqRRfxIfGwfN9aZE0wXAmDM bV6GXngqKkb2nZqkvT96obJr4R369a6YyjBDl6PrejdIU+ZI47pSzUEMrr/rcc0yMc BDN4iV89VraPSpbqeGEYXRwyJb2KYFONUmUYS1LrZJuasGJGGAUBDhuSMS641/FXM1 W3hugLpyCn3LFZxlXrEPJn0BHMFcP2WWY6x+aBvieUUVupSmOsUSIxZA8aU+9Vz3cH olQK/2rxgk+Jw== Date: Wed, 12 Mar 2025 17:54:37 +0100 From: Pablo Neira Ayuso To: Florian Westphal Cc: netfilter-devel@vger.kernel.org Subject: Re: [PATCH nf-next] netfilter: nf_conntrack: speed up reads from nf_conntrack proc file Message-ID: References: <20250211130313.31433-1-fw@strlen.de> Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250211130313.31433-1-fw@strlen.de> Hi Florian, a few comments below. On Tue, Feb 11, 2025 at 02:03:06PM +0100, Florian Westphal wrote: > Dumping all conntrack entries via proc interface can take hours due to > linear search to skip entries dumped so far in each cycle. > > Apply same strategy used to speed up ipvs proc reading done in > commit 178883fd039d ("ipvs: speed up reads from ip_vs_conn proc file") > to nf_conntrack. > > Note that the ctnetlink interface doesn't suffer from this problem. > > Signed-off-by: Florian Westphal > --- > net/netfilter/nf_conntrack_standalone.c | 73 +++++++++++++------------ > 1 file changed, 38 insertions(+), 35 deletions(-) > > diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c > index 502cf10aab41..2a79e690470a 100644 > --- a/net/netfilter/nf_conntrack_standalone.c > +++ b/net/netfilter/nf_conntrack_standalone.c > @@ -98,51 +98,34 @@ struct ct_iter_state { > struct seq_net_private p; > struct hlist_nulls_head *hash; > unsigned int htable_size; > + unsigned int skip_elems; > unsigned int bucket; > u_int64_t time_now; > }; > > -static struct hlist_nulls_node *ct_get_first(struct seq_file *seq) > +static struct nf_conntrack_tuple_hash *ct_get_next(struct ct_iter_state *st) > { > - struct ct_iter_state *st = seq->private; > + struct nf_conntrack_tuple_hash *h; > struct hlist_nulls_node *n; > + unsigned int i; > > - for (st->bucket = 0; > - st->bucket < st->htable_size; > - st->bucket++) { > - n = rcu_dereference( > - hlist_nulls_first_rcu(&st->hash[st->bucket])); > - if (!is_a_nulls(n)) > - return n; > - } > - return NULL; > -} > + for (i = st->bucket; i < st->htable_size; i++) { > + unsigned int skip = 0; > > -static struct hlist_nulls_node *ct_get_next(struct seq_file *seq, > - struct hlist_nulls_node *head) > -{ > - struct ct_iter_state *st = seq->private; > + hlist_nulls_for_each_entry(h, n, &st->hash[i], hnnode) { hlist_nulls_for_each_entry_rcu ? > + if (skip >= st->skip_elems) { > + st->bucket = i; > + return h; > + } > > - head = rcu_dereference(hlist_nulls_next_rcu(head)); > - while (is_a_nulls(head)) { > - if (likely(get_nulls_value(head) == st->bucket)) { > - if (++st->bucket >= st->htable_size) > - return NULL; > + ++skip; > } > - head = rcu_dereference( > - hlist_nulls_first_rcu(&st->hash[st->bucket])); This does not rewind if get_nulls_value(head) != st->bucket), not needed anymore? > - } > - return head; > -} > > -static struct hlist_nulls_node *ct_get_idx(struct seq_file *seq, loff_t pos) > -{ > - struct hlist_nulls_node *head = ct_get_first(seq); > + st->skip_elems = 0; > + } > > - if (head) > - while (pos && (head = ct_get_next(seq, head))) > - pos--; > - return pos ? NULL : head; > + st->bucket = i; > + return NULL; > } > > static void *ct_seq_start(struct seq_file *seq, loff_t *pos) > @@ -154,13 +137,33 @@ static void *ct_seq_start(struct seq_file *seq, loff_t *pos) > rcu_read_lock(); > > nf_conntrack_get_ht(&st->hash, &st->htable_size); > - return ct_get_idx(seq, *pos); > + > + if (*pos == 0) { > + st->skip_elems = 0; > + st->bucket = 0; > + } > + > + return ct_get_next(st); > } > > static void *ct_seq_next(struct seq_file *s, void *v, loff_t *pos) > { > + struct nf_conntrack_tuple_hash *h = v; > + struct ct_iter_state *st = s->private; > + struct hlist_nulls_node *n; > + > (*pos)++; > - return ct_get_next(s, v); > + > + /* more on same hash chain? */ > + n = rcu_dereference(hlist_nulls_next_rcu(&h->hnnode)); > + if (n && !is_a_nulls(n)) { > + st->skip_elems++; > + return hlist_nulls_entry(n, struct nf_conntrack_tuple_hash, hnnode); > + } > + > + st->skip_elems = 0; > + st->bucket++; > + return ct_get_next(st); > } > > static void ct_seq_stop(struct seq_file *s, void *v) > -- > 2.45.3 > >