From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qv1-f73.google.com (mail-qv1-f73.google.com [209.85.219.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9DE6033A02B for ; Fri, 21 Nov 2025 08:33:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763713994; cv=none; b=JdKGcU2de4JNHj5IckT7UpVpSZs4b0xO0PjlHe6A3EKiHyjzovy1Z/N4q5v6lVkJgEg8nX6Z0q5RbAvTDDFXks4fD1Uq34U/+7P+bvEHPM1jECr96PUHF8QE85S2cA39bHqGahLTsYZK158lsjhYse6JqeTeTj6L7EQ+EPAxUxA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763713994; c=relaxed/simple; bh=hQWilFT4N74eUvM8aeubIw76354Td+kefIBnh194ris=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=fNL4tiVy2P7InopmMkw7pKbbp89uY9D1w3kLVqkDvWpOtA+mph9Ta4X5K9IDZTNdKuFjdLxdziX85Q9A8zHRBHjS171T3zD9ZxfwpFIdrqDLaTNcYP/WR/VKg+rjjDWVhqdYzcX1E8d7AzgKKJ48ON0GSCngqLlhjKg1fc2b/Kc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=MNnepu+N; arc=none smtp.client-ip=209.85.219.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="MNnepu+N" Received: by mail-qv1-f73.google.com with SMTP id 6a1803df08f44-8824f62b614so57256596d6.0 for ; Fri, 21 Nov 2025 00:33:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1763713991; x=1764318791; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=YOYqtLViuD52P/GQflD60QINVtQoHqDNLW4K39813P0=; b=MNnepu+NTP0GlJ49tMVStBuI8ciQ6j70cGzFt4CdbetDTkjGzP0yiDFn1Wq+G4dTnY L4EhVftK35gx2fEqP2ijdWMA/WAitmGConOJaxesgA+0dCcqTTkgSPJrjOIAWACW/gLB qNqghMb1vUbpz1qOsXjW2jtx75EHxSknYWmscZcbAsSSvE8v2gHRhsJSJTR8q1jiP0Yn 0DzoirhR5dye/052zs5gtcf/fGzt04s2RfZ+n5aidy87YTyYANHptrOlAruX5olsinD/ kSzKy8YREggTZlbaIfB1TrDyEvDHj3gZQFKQRSll9ClUJOAA83TatTotcuazq1V1G7IL UJxA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1763713991; x=1764318791; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=YOYqtLViuD52P/GQflD60QINVtQoHqDNLW4K39813P0=; b=JCLN6ngOeNlQj10ypFls1lZcp6R66+JXPR/3Gx1XdXRg5q9voHeoFcqmPlbsaXrplH osa+xWKc34epJAdlpTmM1CriQb3qdN0aISlElB55k7uqQCkZUw5SKLbs/Y07dpNpUGwd 7OEVEUPwG919LizGFCRRQcfN3XFyS+Y/kuU+cdgUYmkfXlRs2EwpqG6ywKlypzkCRYft ERTki+3SATfbtzQnrDIoHXBUZPkJAH1KuiydKtzUKxRCqEij52gwVyCCF1eqfls3ydcz IJTPShJZpqO/6lbxyFaceXTnEjgoDSJfQJaacGcbEX4fbvUWH6zESGrSZYwOnZUouwQV ACpQ== X-Forwarded-Encrypted: i=1; AJvYcCXWIqsSfXl0Nw2seYjDLPFh05aCUFJ8IAhXZoGWwV+FnrfpuqA9xCoZR5xZQwDJP/jbixRUfbA=@vger.kernel.org X-Gm-Message-State: AOJu0YyWnWN/JmradLJjvCfHIeBf8ywGPAT7DEEXvcSELgJ26x0NuEM9 n6ySnzlnrEsTjhpZ+vm4/Er+CngCZZVdWpVjjCsbO6vjy7lLhWNm2+Q9logLvokBCN2MV8Zx+9K l39i84BwdoNTybA== X-Google-Smtp-Source: AGHT+IF/srsKD3oFfjjNQrJue4kHHOTHte2URKptos8olPZevLLyuzEWWdD+3qjq/Ct66sDxkWhZureJc6GAMQ== X-Received: from qvboo13.prod.google.com ([2002:a05:6214:450d:b0:882:4d6e:ae58]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:ad4:5c8e:0:b0:880:535d:d157 with SMTP id 6a1803df08f44-8847c544e8dmr21666806d6.31.1763713991553; Fri, 21 Nov 2025 00:33:11 -0800 (PST) Date: Fri, 21 Nov 2025 08:32:52 +0000 In-Reply-To: <20251121083256.674562-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251121083256.674562-1-edumazet@google.com> X-Mailer: git-send-email 2.52.0.460.gd25c4c69ec-goog Message-ID: <20251121083256.674562-11-edumazet@google.com> Subject: [PATCH v3 net-next 10/14] net: prefech skb->priority in __dev_xmit_skb() From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Jamal Hadi Salim , Cong Wang , Jiri Pirko , "=?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?=" , Kuniyuki Iwashima , Willem de Bruijn , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet Content-Type: text/plain; charset="UTF-8" Most qdiscs need to read skb->priority at enqueue time(). In commit 100dfa74cad9 ("net: dev_queue_xmit() llist adoption") I added a prefetch(next), lets add another one for the second half of skb. Note that skb->priority and skb->hash share a common cache line, so this patch helps qdiscs needing both fields. Signed-off-by: Eric Dumazet --- net/core/dev.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/core/dev.c b/net/core/dev.c index e19eb4e9d77c27535ab2a0ce14299281e3ef9397..53e2496dc4292284072946fd9131d3f9a0c0af44 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4246,6 +4246,7 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, llist_for_each_entry_safe(skb, next, ll_list, ll_node) { prefetch(next); + prefetch(&next->priority); skb_mark_not_on_list(skb); rc = dev_qdisc_enqueue(skb, q, &to_free, txq); count++; -- 2.52.0.460.gd25c4c69ec-goog