From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-vs1-f73.google.com (mail-vs1-f73.google.com [209.85.217.73]) (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 AA3D52EBBA2 for ; Fri, 27 Jun 2025 20:06:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.217.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751054762; cv=none; b=X8Wgzw6pLRIcIkW8GYIGnGZKrxAepL81G4FDPKNT3tIb9S1dclwaIlcWk6GgSSGYp7TUqhQ1JzMgeotF/9MYUb+fnHt4+23BGh59gzoEjCAtgLcB4vFOded2/PLv0uht3Hv8ZSSmgBAei2+Z0JLasafnzEy35uxIwQbkp2iNhZo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751054762; c=relaxed/simple; bh=Du1qZrT3TOJNH6FmPwsangSCzhKd8CnHvM4SYt9pHhc=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=db6HILWAPgHIUXnr1g4rGY+Zii7WJNjtNTbXMnPDxjJhO+anRp685rFdMirGsJsR1l5hcCzbcg1uuXUjp/cQvBvZvzsc35Dw/YQY21QdklByfpg1Z8KQcWGhFIJpZ/wz/aZyzqYYj8SfuQ/+zkyBDtRCL+McGK5IMn6U0ZbvcLE= 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=TeLESdPQ; arc=none smtp.client-ip=209.85.217.73 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="TeLESdPQ" Received: by mail-vs1-f73.google.com with SMTP id ada2fe7eead31-4d5ef3b8038so70108137.1 for ; Fri, 27 Jun 2025 13:06:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1751054759; x=1751659559; 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=57UsLn7SBpqt8BKXbwjQjMf0Ho5ZNSkxI4OBXU+iVcw=; b=TeLESdPQjwDkYlTHH7llYZndPQmoI8XjWzRHUP/1ZG7P2mUzoUB3U2xKu/8ovF6+fi QPjDCgAffM7eJ7O6jeKPqT4HgdeL/v+txuBYStBTiyfIT9KYeE93viuJ8dbwSDEKzlDu iH4KyhCU4z+LxGt8kYOSnWwgbW5n16lk95wI3q2HwFJV6xrEBl+T400LafbKKIxQYwJA HmvvAUqjy5NL8tab0MkJPeIDfX8YtDMl1RyHitPe81EePXtbBUilDL+7emAGdncjB6VW tttkuTBafSIOCGckaXSlTX0t+EOjBAbaNkcGgKfNy7qKm3MmrHupkYEi6B5Wp5N9indf uIPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751054759; x=1751659559; 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=57UsLn7SBpqt8BKXbwjQjMf0Ho5ZNSkxI4OBXU+iVcw=; b=n/cPh64wHJ5wRb86Vi6G+eBjsHCODOoC1RGD/tFW05CB4E5mXt0GE/wAH9c/KPmN43 UinluKnW2Wz8TkIn7icWmGjCQ8X8HBIzxKfhuDjlSoh5DaXpipv74v6FP9jw6IZAofxu aNzr+EmGdhJVebLE4DAh6kui3AnNC9zTPc7L35dWr65ZM61ojFwZWsSGvZk82ieO2qjr 3Xx5I+8xqX4WwvX3lSY5ZGU9Rw+qOMognS+RtiWCD28na0p0QOlFDZcB2p1k6T6rIQ2H cijVLg9tVOQqzPRnfczn+R8w51Yq/+SFjec4IuJYCjxRJPW/etISOJ93QCMyKDxe+WKE PgPQ== X-Forwarded-Encrypted: i=1; AJvYcCVFwGDfsyhc61muuAwPV55NtKiB05CDGrycCbcr4mAClJct5xz9mlmvlT52KU0+iRE6DEvxw0A=@vger.kernel.org X-Gm-Message-State: AOJu0YwJk2099LP6ZofWupTJMe/zb2w9tFN/K2DfuYGcTR5vDblr5ulX xa5KlBtx3mxY1YQeHy5mKDu6UjZN5WKwh0qo5Dl7iKmNS7GDYqB5EZA3D2btZ48su24Igs1rtkN nViy+6bfcmgAQaQ== X-Google-Smtp-Source: AGHT+IEzXZ6ShOa4b2rxvx1lEwTHY3dYELpkYDjdIavxLGMMuz/9JHhPfjhJA3S8al+Q6BSql1rdXvuh9swtpg== X-Received: from vsbbu3.prod.google.com ([2002:a05:6102:5243:b0:4eb:eedf:3181]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6102:3712:b0:4e9:b793:1977 with SMTP id ada2fe7eead31-4ee4f0a83cfmr4609485137.0.1751054759562; Fri, 27 Jun 2025 13:05:59 -0700 (PDT) Date: Fri, 27 Jun 2025 20:05:48 +0000 In-Reply-To: <20250627200551.348096-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250627200551.348096-1-edumazet@google.com> X-Mailer: git-send-email 2.50.0.727.gbf7dc18ff4-goog Message-ID: <20250627200551.348096-2-edumazet@google.com> Subject: [PATCH net-next 1/4] net: add struct net_aligned_data From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Willem de Bruijn , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet Content-Type: text/plain; charset="UTF-8" This structure will hold networking data that must consume a full cache line to avoid accidental false sharing. Signed-off-by: Eric Dumazet --- include/net/aligned_data.h | 16 ++++++++++++++++ net/core/hotdata.c | 3 +++ 2 files changed, 19 insertions(+) create mode 100644 include/net/aligned_data.h diff --git a/include/net/aligned_data.h b/include/net/aligned_data.h new file mode 100644 index 0000000000000000000000000000000000000000..cf3329d7c2272ec4424e89352626800cbc282663 --- /dev/null +++ b/include/net/aligned_data.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _NET_ALIGNED_DATA_H +#define _NET_ALIGNED_DATA_H + +#include + +/* Structure holding cacheline aligned fields on SMP builds. + * Each field or group should have an ____cacheline_aligned_in_smp + * attribute to ensure no accidental false sharing can happen. + */ +struct net_aligned_data { +}; + +extern struct net_aligned_data net_aligned_data; + +#endif /* _NET_ALIGNED_DATA_H */ diff --git a/net/core/hotdata.c b/net/core/hotdata.c index 0bc893d5f07b03b31e08967a2238f63d218020d7..e9c03491ab001cc85fd60ad28533649b32d8a003 100644 --- a/net/core/hotdata.c +++ b/net/core/hotdata.c @@ -2,6 +2,7 @@ #include #include #include +#include #include #include @@ -22,3 +23,5 @@ struct net_hotdata net_hotdata __cacheline_aligned = { .sysctl_mem_pcpu_rsv = SK_MEMORY_PCPU_RESERVE }; EXPORT_SYMBOL(net_hotdata); + +struct net_aligned_data net_aligned_data; -- 2.50.0.727.gbf7dc18ff4-goog