From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B10DC433F5 for ; Wed, 6 Apr 2022 15:03:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235475AbiDFPFZ (ORCPT ); Wed, 6 Apr 2022 11:05:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235586AbiDFPFR (ORCPT ); Wed, 6 Apr 2022 11:05:17 -0400 Received: from mail-pg1-f170.google.com (mail-pg1-f170.google.com [209.85.215.170]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E9380F8443 for ; Wed, 6 Apr 2022 04:55:56 -0700 (PDT) Received: by mail-pg1-f170.google.com with SMTP id d185so1963746pgc.13 for ; Wed, 06 Apr 2022 04:55:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=4++eNCxtKqRX8gh1V4vVECxQ8shO4YyrKKIugHCp4UM=; b=buI0RaeJ8PPKpYmzACr+RSufvG5aoBJOYMUYukXKVc+wNnf9TXxtskyCmYHV6CLmKP i6mHoyXaeS2FPlddjMrmFxd81ifI46qaMtJaCma35GBdSTwLUPV1SMozY8ftxiW7Uo1T ia5M7Yhoj+MdoGBR2/eiiL8gzxDdyIWE8//Sr0ElM5IXZNT87JYM1EQMcLBx9GsNEneB Fq6TjJHRcfYBWeDg3ZCay/gxcwr0I+vXOyUMnC+4RAENt3gkwQ5bnL1aeYaVTx7PH6Bw 7TNiVy6wo5c9x9bCzaKAacbZ/T/GAoRiK0OzBDiuxY4h/YPizmbPwwELg+u1T2foLLMc fteQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=4++eNCxtKqRX8gh1V4vVECxQ8shO4YyrKKIugHCp4UM=; b=JrlxsxAHKFODkPWxSW/+dWZ8B1vXAkac53GU6B1H4bOcvfRMdqcIMYHJ8gArHLi2xv zsl0Xyxxo+wDmtRL1QAD2TcBV8fmJU3MG7lNKW347/V12+TJvoAs86W6nvrsqFPjoejh FTP32U9ff+W+ZFZF9blnCU6zU9AAMvF8RNsULICvX7Nn6WozaYVj5XyfSC6I6qPTQTXs prMfl0hxLDATKIuHUuQuxBhbYTiHr/pc7X8AJ/A8AAqDDp30juZi238LMZByfGNZWDm6 r46nc+gPvuBZoN7PqNZ43aILmhdwnbqQeefVPCl6016Me9MG43zBLIqI3UEW0+wonjtK ob+w== X-Gm-Message-State: AOAM533GJvkq2WcsfLh0+zKmr7CK7kNf4+qbbhP3FMJz8E5GT/cbL/zz Ks9B9l2stXAMya7jE9DdBKw= X-Google-Smtp-Source: ABdhPJzgJ7s88d9M9teatbRe2jj1m6kMIbq7KctuSswjwg7mHtSJ/OhxkTTrv9nIJSo6AZpgitT98g== X-Received: by 2002:a63:b555:0:b0:398:4ca1:4be0 with SMTP id u21-20020a63b555000000b003984ca14be0mr6721514pgo.294.1649245767758; Wed, 06 Apr 2022 04:49:27 -0700 (PDT) Received: from localhost.localdomain ([223.104.68.74]) by smtp.gmail.com with ESMTPSA id j2-20020a17090a588200b001ca37c215aasm5477689pji.2.2022.04.06.04.49.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 06 Apr 2022 04:49:27 -0700 (PDT) From: lianglixue X-Google-Original-From: lianglixue To: davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com Cc: edumazet@google.com, pablo@netfilter.org, rsanger@wand.net.nz, yajun.deng@linux.dev, jiapeng.chong@linux.alibaba.com, netdev@vger.kernel.org, lianglixue Subject: [PATCH] af_packet: fix efficiency issues in packet_read_pending Date: Wed, 6 Apr 2022 11:48:07 +0000 Message-Id: <20220406114807.1803-1-lianglixue@greatwall.com.cn> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org In packet_read_pengding, even if the pending_refcnt of the first CPU is not 0, the pending_refcnt of all CPUs will be traversed, and the long delay of cross-cpu access in NUMA significantly reduces the performance of packet sending; especially in tpacket_destruct_skb. When pending_refcnt is not 0, it returns without counting the number of all pending packets, which significantly reduces the traversal time. Signed-off-by: lianglixue --- net/packet/af_packet.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index c39c09899fd0..c04f49e44a33 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1210,17 +1210,18 @@ static void packet_dec_pending(struct packet_ring_buffer *rb) static unsigned int packet_read_pending(const struct packet_ring_buffer *rb) { - unsigned int refcnt = 0; int cpu; /* We don't use pending refcount in rx_ring. */ if (rb->pending_refcnt == NULL) return 0; - for_each_possible_cpu(cpu) - refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu); + for_each_possible_cpu(cpu) { + if (*per_cpu_ptr(rb->pending_refcnt, cpu) != 0) + return 1; + } - return refcnt; + return 0; } static int packet_alloc_pending(struct packet_sock *po) -- 2.27.0