From patchwork Tue Apr 9 06:44:12 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Magnus Karlsson X-Patchwork-Id: 1081926 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=intel.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44dd7g6vgyz9sRC for ; Tue, 9 Apr 2019 16:44:47 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726568AbfDIGop (ORCPT ); Tue, 9 Apr 2019 02:44:45 -0400 Received: from mga04.intel.com ([192.55.52.120]:18780 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726528AbfDIGoo (ORCPT ); Tue, 9 Apr 2019 02:44:44 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Apr 2019 23:44:43 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,328,1549958400"; d="scan'208";a="289943834" Received: from mkarlsso-mobl.ger.corp.intel.com (HELO VM.isw.intel.com) ([10.103.211.40]) by orsmga004.jf.intel.com with ESMTP; 08 Apr 2019 23:44:39 -0700 From: Magnus Karlsson To: magnus.karlsson@intel.com, bjorn.topel@intel.com, ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org Cc: bpf@vger.kernel.org, bruce.richardson@intel.com, ciara.loftus@intel.com, ilias.apalodimas@linaro.org, xiaolong.ye@intel.com, ferruh.yigit@intel.com, qi.z.zhang@intel.com, georgmueller@gmx.net Subject: [PATCH bpf 1/2] libbpf: remove likely/unlikely in xsk.h Date: Tue, 9 Apr 2019 08:44:12 +0200 Message-Id: <1554792253-27081-2-git-send-email-magnus.karlsson@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1554792253-27081-1-git-send-email-magnus.karlsson@intel.com> References: <1554792253-27081-1-git-send-email-magnus.karlsson@intel.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch removes the use of likely and unlikely in xsk.h since they create a dependency on Linux headers as reported by several users. There have also been reports that the use of these decreases performance as the compiler puts the code on two different cache lines instead of on a single one. All in all, I think we are better off without them. Fixes: 1cad07884239 ("libbpf: add support for using AF_XDP sockets") Signed-off-by: Magnus Karlsson --- tools/lib/bpf/xsk.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/xsk.h b/tools/lib/bpf/xsk.h index a497f00..3638147 100644 --- a/tools/lib/bpf/xsk.h +++ b/tools/lib/bpf/xsk.h @@ -105,7 +105,7 @@ static inline __u32 xsk_cons_nb_avail(struct xsk_ring_cons *r, __u32 nb) static inline size_t xsk_ring_prod__reserve(struct xsk_ring_prod *prod, size_t nb, __u32 *idx) { - if (unlikely(xsk_prod_nb_free(prod, nb) < nb)) + if (xsk_prod_nb_free(prod, nb) < nb) return 0; *idx = prod->cached_prod; @@ -129,7 +129,7 @@ static inline size_t xsk_ring_cons__peek(struct xsk_ring_cons *cons, { size_t entries = xsk_cons_nb_avail(cons, nb); - if (likely(entries > 0)) { + if (entries > 0) { /* Make sure we do not speculatively read the data before * we have received the packet buffers from the ring. */