From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yb1-f201.google.com (mail-yb1-f201.google.com [209.85.219.201]) (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 10D0B3FB22 for ; Wed, 21 Feb 2024 10:59:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708513179; cv=none; b=jGsXqpo03aPKTs3WWRGLax1ryJzMUgRTtxlMuIn8e3CMOngJIrwxLj9E0lYSLy1JCoCHMQoRoOwrHo9HMUlD9UtqztWIT4vOlfPUU/++IAmGYlu4zGusn8IPSYJ1WAXw0c11bduMeGv9cgEkzlmPoIu71bjcJ1RdHRIoPEHEhTk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708513179; c=relaxed/simple; bh=vOLe3bg0tRXIFmKpzHwgXmIPPTfHKKHk3L3/HNjTD28=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=t9zAIdPszaTcd0VInaePEm5iSsorWUfhqEZRzJ+l+vOJD3kVZn1G1tLYJW3hBAbugcV0jPLasKVtPkimLel7Dl9bTf0OmZiIL/bKWKBpHFKWmNPUAOKhD5gLL3TeO6oH9vfsXhAMk6SnvNG/+8tjiMQ82WTwxw6UMfKcHnwfyBU= 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=g5ho4xaE; arc=none smtp.client-ip=209.85.219.201 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="g5ho4xaE" Received: by mail-yb1-f201.google.com with SMTP id 3f1490d57ef6-dc6dbdcfd39so938505276.2 for ; Wed, 21 Feb 2024 02:59:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1708513177; x=1709117977; 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=7sVU0GIN3o9YbvdKGN4zAa6quKptpEydRku+6jdZ/QI=; b=g5ho4xaE7T+vxiuBCEP3nPgjqOlIcVb56XSXBLJawGP//NZe44f2PSk1536pfAjYSL baV9VqNDIR8drwVjbI+la0pEZbycsiQ1GTtNX+NzWfkWMYO8Z95kjcO+85f3+Pkxy859 HtZQQriuGFdW36aN2oJLjm/s971o2HXo4X2dBdjXldg9P2kHlBbLEobDmOvUNTXMF11H Ac+BrPT2tF7hlVC5QXYvkn4AN8qWqFBCMFNFW41mgQaRybWPAx16PZOx6TNI5e4/lx3+ Sot+HPe4SM4tEM1X8Q4QzcDtSC0EwtziQnK3zsC14OvtH80nj2xEJfM7Z/Ftm6xD7vF0 wgHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1708513177; x=1709117977; 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=7sVU0GIN3o9YbvdKGN4zAa6quKptpEydRku+6jdZ/QI=; b=gBQX7DIq+wjhB/8jyXtIrDmA5CYTJwgrl1Vkn9PV7RvTWo3uV2xWhsCJY0Wo8tOm/y 28Vjx1HJfpN1qFYFrc4jxRuIvjLOwV0f7UgYCMMioHGztxLTrdKAm+/JuZBS+4WWH+QW 8BS665++QvWRDV/96bfeGdHykRuKcRiYTyeIbq17Dmp0icHfq0iGNoCFWHkCc2Q1BTWk h7fIwkPIjb6ep6Sz9j6l+Ygt7GY+MP9UAfvGntS2OGgy5aIIg2xp8OzmP4V2uSdTeYtq b8xF+DrGy+YUSTSYW85lARSoBQ6FBo5wFfuLeNPUaM5Jr4oTjSmwU7IlT75Krg5EfIaw DSwg== X-Gm-Message-State: AOJu0Yz3lm8l0R35by1iijc1sK7fW165XfxAH9Oktng3mW+Z4PqTGkhB DMACZhi7YScgoMCd+SpvXsZqV7IIuwM/dLczDM9X+n6/zVIfPZc64oSZznFVITwPXAC8ZzP8StM bY9f5++oL8w== X-Google-Smtp-Source: AGHT+IGA8Xl2wHNAOn24MgSj6nut2crct/U6FS9WFAEhRs7znk0upBrqT8Jw7f2lrhnMhrlz9YjpJHvQlLxldA== X-Received: from edumazet1.c.googlers.com ([fda3:e722:ac3:cc00:2b:7d90:c0a8:395a]) (user=edumazet job=sendgmr) by 2002:a05:6902:1209:b0:dc6:9e4a:f950 with SMTP id s9-20020a056902120900b00dc69e4af950mr4489487ybu.3.1708513177138; Wed, 21 Feb 2024 02:59:37 -0800 (PST) Date: Wed, 21 Feb 2024 10:59:14 +0000 In-Reply-To: <20240221105915.829140-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240221105915.829140-1-edumazet@google.com> X-Mailer: git-send-email 2.44.0.rc0.258.g7320e95886-goog Message-ID: <20240221105915.829140-13-edumazet@google.com> Subject: [PATCH net-next 12/13] rtnetlink: make rtnl_fill_link_ifmap() RCU ready From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet Content-Type: text/plain; charset="UTF-8" Use READ_ONCE() to read the following device fields: dev->mem_start dev->mem_end dev->base_addr dev->irq dev->dma dev->if_port Provide IFLA_MAP attribute only if at least one of these fields is not zero. This saves some space in the output skb for most devices. Signed-off-by: Eric Dumazet --- net/core/rtnetlink.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 1b26dfa5668d22fb2e30ceefbf143e98df13ae29..b91ec216c593aaebf97ea69aa0d2d265ab61c098 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1455,19 +1455,21 @@ static noinline_for_stack int rtnl_fill_vf(struct sk_buff *skb, return 0; } -static int rtnl_fill_link_ifmap(struct sk_buff *skb, struct net_device *dev) +static int rtnl_fill_link_ifmap(struct sk_buff *skb, + const struct net_device *dev) { struct rtnl_link_ifmap map; memset(&map, 0, sizeof(map)); - map.mem_start = dev->mem_start; - map.mem_end = dev->mem_end; - map.base_addr = dev->base_addr; - map.irq = dev->irq; - map.dma = dev->dma; - map.port = dev->if_port; - - if (nla_put_64bit(skb, IFLA_MAP, sizeof(map), &map, IFLA_PAD)) + map.mem_start = READ_ONCE(dev->mem_start); + map.mem_end = READ_ONCE(dev->mem_end); + map.base_addr = READ_ONCE(dev->base_addr); + map.irq = READ_ONCE(dev->irq); + map.dma = READ_ONCE(dev->dma); + map.port = READ_ONCE(dev->if_port); + /* Only report non zero information. */ + if (memchr_inv(&map, 0, sizeof(map)) && + nla_put_64bit(skb, IFLA_MAP, sizeof(map), &map, IFLA_PAD)) return -EMSGSIZE; return 0; @@ -1875,9 +1877,6 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, goto nla_put_failure; } - if (rtnl_fill_link_ifmap(skb, dev)) - goto nla_put_failure; - if (dev->addr_len) { if (nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr) || nla_put(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast)) @@ -1927,6 +1926,9 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, rcu_read_lock(); if (rtnl_fill_link_af(skb, dev, ext_filter_mask)) goto nla_put_failure_rcu; + if (rtnl_fill_link_ifmap(skb, dev)) + goto nla_put_failure_rcu; + rcu_read_unlock(); if (rtnl_fill_prop_list(skb, dev)) -- 2.44.0.rc0.258.g7320e95886-goog