From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [PATCH nftables 6/6] src: add trace support to nft monitor mode Date: Tue, 24 Nov 2015 11:53:33 +0100 Message-ID: <20151124105333.GA3212@salvia> References: <1448359331-12692-1-git-send-email-fw@strlen.de> <1448359331-12692-7-git-send-email-fw@strlen.de> <20151124102553.GE2310@macbook.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Florian Westphal , netfilter-devel@vger.kernel.org To: Patrick McHardy Return-path: Received: from mail.us.es ([193.147.175.20]:51060 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753529AbbKXKxl (ORCPT ); Tue, 24 Nov 2015 05:53:41 -0500 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 36BBFDA86C for ; Tue, 24 Nov 2015 11:53:40 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 18F6ADA804 for ; Tue, 24 Nov 2015 11:53:40 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 24DA3DA85F for ; Tue, 24 Nov 2015 11:53:38 +0100 (CET) Content-Disposition: inline In-Reply-To: <20151124102553.GE2310@macbook.localdomain> Sender: netfilter-devel-owner@vger.kernel.org List-ID: On Tue, Nov 24, 2015 at 10:25:54AM +0000, Patrick McHardy wrote: > Tracing might be a long running operation. The cache can go out of sync, might > be better to do a lookup on demand. We'll need to handle generations in that approach. The kernel lookup per trace will be expensive. Why not just keep the cache in userspace and update it only when needed? We can easily detect when we get out of sync via ENOBUFS. > Right now the caching infrastrucure has quite a lot of problems and I'd prefer > to get them fixed before we base new things on it. The caching infrastructure only needs to have a mode to be populated via set information, then infer existing tables from handles as you indicated. What other problems you see with it?