From patchwork Fri Mar 12 16:21:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Lobakin X-Patchwork-Id: 12135219 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 1F519C433DB for ; Fri, 12 Mar 2021 16:22:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DEA5E6501D for ; Fri, 12 Mar 2021 16:22:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232229AbhCLQWU (ORCPT ); Fri, 12 Mar 2021 11:22:20 -0500 Received: from mail-40134.protonmail.ch ([185.70.40.134]:59365 "EHLO mail-40134.protonmail.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231789AbhCLQWB (ORCPT ); Fri, 12 Mar 2021 11:22:01 -0500 Date: Fri, 12 Mar 2021 16:21:58 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pm.me; s=protonmail; t=1615566119; bh=pYXdNgxXLm9jRXofMIKcS3j5jzWazEkuwrSWkfABQ9g=; h=Date:To:From:Cc:Reply-To:Subject:In-Reply-To:References:From; b=KVNUVCXhng00EaJ920Tvs0q2twphNZCSQ9ASVAuEhst+KRNaP9DVlBsl5Hy5tYvRd 5iQbqrn2C7/5qQY9GdtYv8HEBXHZ59qPjNntmZbPU2sJZJfoDKzUIeWNEe2TmEVZmS EACJ8ZLlJNr3o3VGGd1JczA0c2Gk5Tp4C5EabU6p0li5HPIbaQpOWPIxu8tLfO1eqL tpSrl2ndnfZpXgQe6CDQvzptlvJsZXzAN3GekjqnWIu1RzPjnHYDhKsGcsuk/jJRdQ EzEi4F3aVhhtLVuA/CXPYOLeDkjpWewV5HCFCCMr6W6Pj6UQA21gdVXKBeluKUCCV/ CX2ULINCyKL5Q== To: "David S. Miller" , Jakub Kicinski From: Alexander Lobakin Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Alexander Lobakin , Eric Dumazet , Wei Wang , Cong Wang , Taehee Yoo , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Reply-To: Alexander Lobakin Subject: [PATCH net-next 2/4] gro: don't dereference napi->gro_hash[x] multiple times in dev_gro_receive() Message-ID: <20210312162127.239795-3-alobakin@pm.me> In-Reply-To: <20210312162127.239795-1-alobakin@pm.me> References: <20210312162127.239795-1-alobakin@pm.me> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org GRO bucket index doesn't change through the entire function. Store a pointer to the corresponding bucket on stack once and use it later instead of dereferencing again and again. Signed-off-by: Alexander Lobakin --- net/core/dev.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) -- 2.30.2 diff --git a/net/core/dev.c b/net/core/dev.c index adc42ba7ffd8..ee124aecb8a2 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5957,6 +5957,7 @@ static void gro_flush_oldest(struct napi_struct *napi, struct list_head *head) static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) { u32 bucket = skb_get_hash_raw(skb) & (GRO_HASH_BUCKETS - 1); + struct gro_list *gro_list = &napi->gro_hash[bucket]; struct list_head *head = &offload_base; struct packet_offload *ptype; __be16 type = skb->protocol; @@ -6024,7 +6025,7 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff if (pp) { skb_list_del_init(pp); napi_gro_complete(napi, pp); - napi->gro_hash[bucket].count--; + gro_list->count--; } if (same_flow) @@ -6033,10 +6034,10 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff if (NAPI_GRO_CB(skb)->flush) goto normal; - if (unlikely(napi->gro_hash[bucket].count >= MAX_GRO_SKBS)) { + if (unlikely(gro_list->count >= MAX_GRO_SKBS)) { gro_flush_oldest(napi, gro_head); } else { - napi->gro_hash[bucket].count++; + gro_list->count++; } NAPI_GRO_CB(skb)->count = 1; NAPI_GRO_CB(skb)->age = jiffies; @@ -6050,7 +6051,7 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff if (grow > 0) gro_pull_from_frag0(skb, grow); ok: - if (napi->gro_hash[bucket].count) { + if (gro_list->count) { if (!test_bit(bucket, &napi->gro_bitmask)) __set_bit(bucket, &napi->gro_bitmask); } else if (test_bit(bucket, &napi->gro_bitmask)) {