From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [RFC PATCH] sock: add SO_RCVQUEUE_SIZE getsockopt Date: Mon, 13 Mar 2017 17:10:08 -0700 (PDT) Message-ID: <20170313.171008.1845413549443399902.davem@davemloft.net> References: <522a2e2d-c288-7019-3f12-2b624d6aa921@akamai.com> <20170313.123933.1813218797817423920.davem@davemloft.net> <9f775c33-01f4-fbd8-4d4d-4ca67f0f6d3b@akamai.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:60192 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751330AbdCNAKJ (ORCPT ); Mon, 13 Mar 2017 20:10:09 -0400 In-Reply-To: <9f775c33-01f4-fbd8-4d4d-4ca67f0f6d3b@akamai.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: johunt@akamai.com Cc: edumazet@google.com, arnd@arndb.de, soheil@google.com, willemb@google.com, pabeni@redhat.com, linux-arch@vger.kernel.org, netdev@vger.kernel.org From: Josh Hunt Date: Mon, 13 Mar 2017 18:34:41 -0500 > In this particular case they really do want to know total # of bytes > in the receive queue, not the data bytes they can consume from an > application pov. The kernel currently only exposes this value through > netlink or /proc/net/udp from what I saw. Can you explain in what way this is useful? The difference between skb->len and skb->truesize is really kernel internal implementation detail, and I'm trying to figure out why this would be useful to an application.