Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933736AbaAFXUj (ORCPT ); Mon, 6 Jan 2014 18:20:39 -0500 Received: from mail-qc0-f178.google.com ([209.85.216.178]:45052 "EHLO mail-qc0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932962AbaAFXUh (ORCPT ); Mon, 6 Jan 2014 18:20:37 -0500 From: Benjamin Poirier To: "David S. Miller" Cc: Eric Dumazet , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Tom Herbert Subject: [PATCH] net: Do not enable tx-nocache-copy by default Date: Mon, 6 Jan 2014 18:20:19 -0500 Message-Id: <1389050419-9060-1-git-send-email-bpoirier@suse.de> X-Mailer: git-send-email 1.8.4 In-Reply-To: <1389041855.12212.210.camel@edumazet-glaptop2.roam.corp.google.com> References: <1389041855.12212.210.camel@edumazet-glaptop2.roam.corp.google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There are many cases where this feature does not improve performance or even reduces it. See the following discussion for example perf numbers: http://thread.gmane.org/gmane.linux.network/298345 CC: Tom Herbert Signed-off-by: Benjamin Poirier --- net/core/dev.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 153ee2f..2e242583 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5783,13 +5783,8 @@ int register_netdevice(struct net_device *dev) dev->features |= NETIF_F_SOFT_FEATURES; dev->wanted_features = dev->features & dev->hw_features; - /* Turn on no cache copy if HW is doing checksum */ if (!(dev->flags & IFF_LOOPBACK)) { dev->hw_features |= NETIF_F_NOCACHE_COPY; - if (dev->features & NETIF_F_ALL_CSUM) { - dev->wanted_features |= NETIF_F_NOCACHE_COPY; - dev->features |= NETIF_F_NOCACHE_COPY; - } } /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. -- 1.8.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/