From patchwork Fri Feb 12 13:50:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jesper Dangaard Brouer X-Patchwork-Id: 12085353 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88750C433DB for ; Fri, 12 Feb 2021 13:52:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4322864E57 for ; Fri, 12 Feb 2021 13:52:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230494AbhBLNwE (ORCPT ); Fri, 12 Feb 2021 08:52:04 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:57281 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229940AbhBLNwD (ORCPT ); Fri, 12 Feb 2021 08:52:03 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613137836; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=pgcM5pVoAqk+OJ43cIdY0aNOABGGz99ON12jih0wfng=; b=e/GWqyfi240hP6IKwqTIUyI7aykt7BqMt5U5gLLYwbr6UFzrqMUodBd3XxtehWlRzYNxMN s1/ZvBzq3HKloAFusJN76S++YChvIjmk/tU+ebiJqYji/eXhigqKwnDHEUa7OVdMBx/v3y roAnG5HdoNNr5SvqQonw4G+Sbg3Mv54= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-465-4XAYY_fgPQK3KNs0N2TRww-1; Fri, 12 Feb 2021 08:50:33 -0500 X-MC-Unique: 4XAYY_fgPQK3KNs0N2TRww-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 87C526EE22; Fri, 12 Feb 2021 13:50:31 +0000 (UTC) Received: from firesoul.localdomain (unknown [10.40.208.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0C01810023AD; Fri, 12 Feb 2021 13:50:27 +0000 (UTC) Received: from [192.168.42.3] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 57C4330736C73; Fri, 12 Feb 2021 14:50:26 +0100 (CET) Subject: [PATCH net-next V1] net: followup adjust net_device layout for cacheline usage From: Jesper Dangaard Brouer To: David Ahern , netdev@vger.kernel.org, Jakub Kicinski , "David S. Miller" Cc: Jesper Dangaard Brouer , Eric Dumazet Date: Fri, 12 Feb 2021 14:50:26 +0100 Message-ID: <161313782625.1008639.6000589679659428869.stgit@firesoul> User-Agent: StGit/0.19 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org As Eric pointed out in response to commit 28af22c6c8df ("net: adjust net_device layout for cacheline usage") the netdev_features_t members wanted_features and hw_features are only used in control path. Thus, this patch reorder the netdev_features_t to let more members that are used in fast path into the 3rd cacheline. Whether these members are read depend on SKB properties, which are hinted as comments. The member mpls_features could not fit in the cacheline, but it was the least commonly used (depend on CONFIG_NET_MPLS_GSO). In the future we should consider relocating member gso_partial_features to be closer to member gso_max_segs. (see usage in gso_features_check()). Suggested-by: Eric Dumazet Signed-off-by: Jesper Dangaard Brouer --- include/linux/netdevice.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index bfadf3b82f9c..3898bb167579 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1890,13 +1890,16 @@ struct net_device { unsigned short needed_headroom; unsigned short needed_tailroom; + /* Fast path features - via netif_skb_features */ netdev_features_t features; + netdev_features_t vlan_features; /* if skb_vlan_tagged */ + netdev_features_t hw_enc_features; /* if skb->encapsulation */ + netdev_features_t gso_partial_features;/* if skb_is_gso */ + netdev_features_t mpls_features; /* if eth_p_mpls+NET_MPLS_GSO */ + + /* Control path features */ netdev_features_t hw_features; netdev_features_t wanted_features; - netdev_features_t vlan_features; - netdev_features_t hw_enc_features; - netdev_features_t mpls_features; - netdev_features_t gso_partial_features; unsigned int min_mtu; unsigned int max_mtu;