From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f50.google.com (mail-wm1-f50.google.com [209.85.128.50]) (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 18D4785C48 for ; Wed, 21 Feb 2024 16:03:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.50 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708531386; cv=none; b=qtpeNDAS9A3qQ02OkdwUyFrJFmL+sKMXpNcDd+Zhuj+7+BU6k2Di/qBq4g+KlOCWGfPuBxlmrwzNYnzsHDji6KLO9iM+jkPX+RZ30VtgEDsVTnLRg1lj2rWaPjO/BOEszbP52YS6a75hAMNHzwfiJ+GGTVcbSTaZy677/Dn8vlE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708531386; c=relaxed/simple; bh=dgKPJgYUdNC4HjonLKTL0MnIIXxZ8wVCNFRZsaKzi8o=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pngw/Xn9s5h4kpLI+qS/PIinMPr8+oUvNWYxcee2qAUcd7eqdy7Rc8KPBBi+Jj/dH0OBp0/aivnXqd9MlhAnWLflNefiSbUsHmVNQ23hcI8YFGzdQ3AtgxKDGZKijFshmt32dpbiNfJEEUHSBnpwQq0DAKJB8apG00atecKO7QE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=resnulli.us; spf=none smtp.mailfrom=resnulli.us; dkim=pass (2048-bit key) header.d=resnulli-us.20230601.gappssmtp.com header.i=@resnulli-us.20230601.gappssmtp.com header.b=JPfLPTXM; arc=none smtp.client-ip=209.85.128.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=resnulli.us Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=resnulli.us Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=resnulli-us.20230601.gappssmtp.com header.i=@resnulli-us.20230601.gappssmtp.com header.b="JPfLPTXM" Received: by mail-wm1-f50.google.com with SMTP id 5b1f17b1804b1-41241f64c6bso5514485e9.0 for ; Wed, 21 Feb 2024 08:03:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=resnulli-us.20230601.gappssmtp.com; s=20230601; t=1708531383; x=1709136183; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=NAyrJ3ysjOKEMv6LdT65oPM2L+c5vBxXeZNYGq9IWlM=; b=JPfLPTXMuGZntUA9CW/Un/0aSzIJtdsr7E241b7mEKpFj+WQMJqoG9QzUYnu4kau/M VNx2te4sAtgVhubepaMaKMb7QYVIP49i0QM7mkdOTzlnLHRhO8v6uRZfwyNtWwT8LIRf MfYWYPK9FOw2HaBW4eICSiHhdGvictavsFVRB7eh2X+V0dykK1syIbDuET9UJ+NDMfYu 0ds5aVmpVfD0yuHHW1CWh1syGNgncwjeVgcoEY0YG0QetJ+0/zu6JilTgHSaG40HZBnI jtU3FJ8U38h6r7SDFHTI0lOEgdBW2XmCasofHt/OOnpH9shqdgPug+DbBMxPrVyco8Cl srRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1708531383; x=1709136183; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=NAyrJ3ysjOKEMv6LdT65oPM2L+c5vBxXeZNYGq9IWlM=; b=GIkPi1zi1yQRPfbbAjDf0eTVcSfjhtI4njRD7HMSzMZDgcP3PmAfnws/geoyracF+l fSIVy0C0Igz2sl9xttdxyce41BAGXbDblu+vaS4qHeRdHd8zfz6mSuXSeuXiszblyVYT hGQch+NRypu+Ag0h6ERNm3YQHT8BMUHIDoLE3iEIGkX8/l1QSLUvilQURSwTXbzGcRpL 5ripLrkuPqsrJnzuRrbxx441LKS8bIxu+iNyiCobNWX3mgWD+oLCwSFMaB7PHTY3N2H9 UvetpH23odMK/Y7lVQm0cUUk5JP1yZ5D7TRx9gpaoF4/58XYE6PeyRkqBWJx/9Nnhd46 clfw== X-Forwarded-Encrypted: i=1; AJvYcCW3zT4BrcJtWrXp/nfXZGqWtngaTjFG6n38n3+tIaNJZgI2EqcPrQc7Ub6Qfrq+6w3IqcsfwadmB/3ODu95yZMn0KOilwR0 X-Gm-Message-State: AOJu0YybQrDcgx1D1MPXnRFDRDkYpaac1cYn97LjjPta1F9EKVX6Q8sx QGxab9aZUZbVVLHOR+EZKFZktUVVsUR5BMl74v0JAEN6F5v7Mx77JR1SwN2qodY= X-Google-Smtp-Source: AGHT+IG4DqJrPLByFyqwe4P1waoeLsQpCYIS9pcst8tLvktOHRLaeDPeYFHYT4Kwigg8jiA24CbBNA== X-Received: by 2002:a5d:5222:0:b0:33d:63c0:3b7f with SMTP id i2-20020a5d5222000000b0033d63c03b7fmr3703675wra.42.1708531383312; Wed, 21 Feb 2024 08:03:03 -0800 (PST) Received: from localhost ([193.47.165.251]) by smtp.gmail.com with ESMTPSA id bx14-20020a5d5b0e000000b0033d6bd4eab9sm6171198wrb.1.2024.02.21.08.03.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Feb 2024 08:03:02 -0800 (PST) Date: Wed, 21 Feb 2024 17:02:59 +0100 From: Jiri Pirko To: Eric Dumazet Cc: "David S . Miller" , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, eric.dumazet@gmail.com Subject: Re: [PATCH net-next 12/13] rtnetlink: make rtnl_fill_link_ifmap() RCU ready Message-ID: References: <20240221105915.829140-1-edumazet@google.com> <20240221105915.829140-13-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240221105915.829140-13-edumazet@google.com> Wed, Feb 21, 2024 at 11:59:14AM CET, edumazet@google.com wrote: >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)) && This check(optimization) is unrelated to the rest of the patch, correct? If yes, could it be a separate patch? >+ 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 > >