From patchwork Sun Nov 22 13:10:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li RongQing X-Patchwork-Id: 1404479 Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=baidu.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4Cf9s4012Xz9sSs for ; Mon, 23 Nov 2020 00:20:55 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727728AbgKVNUe (ORCPT ); Sun, 22 Nov 2020 08:20:34 -0500 Received: from mx57.baidu.com ([61.135.168.57]:41196 "EHLO tc-sys-mailedm04.tc.baidu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727567AbgKVNUe (ORCPT ); Sun, 22 Nov 2020 08:20:34 -0500 X-Greylist: delayed 592 seconds by postgrey-1.27 at vger.kernel.org; Sun, 22 Nov 2020 08:20:33 EST Received: from localhost (bjhw-sys-rpm015653cc5.bjhw.baidu.com [10.227.53.39]) by tc-sys-mailedm04.tc.baidu.com (Postfix) with ESMTP id CD117236C003; Sun, 22 Nov 2020 21:10:19 +0800 (CST) From: Li RongQing To: netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH] libbpf: add support for canceling cached_cons advance Date: Sun, 22 Nov 2020 21:10:23 +0800 Message-Id: <1606050623-22963-1-git-send-email-lirongqing@baidu.com> X-Mailer: git-send-email 1.7.1 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org It is possible to fail receiving packets after calling xsk_ring_cons__peek, at this condition, cached_cons has been advanced, should be cancelled. Signed-off-by: Li RongQing Reported-by: kernel test robot Reported-by: kernel test robot --- tools/lib/bpf/xsk.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/lib/bpf/xsk.h b/tools/lib/bpf/xsk.h index 1069c46364ff..4128215c246b 100644 --- a/tools/lib/bpf/xsk.h +++ b/tools/lib/bpf/xsk.h @@ -153,6 +153,12 @@ static inline size_t xsk_ring_cons__peek(struct xsk_ring_cons *cons, return entries; } +static inline void xsk_ring_cons__cancel(struct xsk_ring_cons *cons, + size_t nb) +{ + rx->cached_cons -= nb; +} + static inline void xsk_ring_cons__release(struct xsk_ring_cons *cons, size_t nb) { /* Make sure data has been read before indicating we are done