From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f201.google.com (mail-qk1-f201.google.com [209.85.222.201]) (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 315B81A7264 for ; Thu, 23 Apr 2026 06:28:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776925724; cv=none; b=kjVAkXdZkRSGXeErARx4d7N0tP+0dkNnWp49V/GbcjO7+xg/BzjJ7DncSp2XbHY5Rtx3w2lhNSt3g7t2e6mZ7CZSjcin/4CQO5DplDTJnKQeIa8Sz/sCkNhwPxk2LHxlIU3Xv1IjPNO257V6ALJxKoh4zTgqlDlThz1/BAxVlWE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776925724; c=relaxed/simple; bh=TIKWurkCeViktvT6vRCxXoXGv6LQQRRCc9UHJ9Nv66Q=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=OyFcnwniYF98u/E6lQSKVcPHwbdBVki6zGIhELJMWiZ+/ya2JWHTLuKJci7fNidax0M1uTiAz0/jdz54/bgPd9KPCvNT90Mj9hKrIDoocIqRcu56rvCLZfga0dTf3VSg3XUbYZH8CRYawcbFrrWKt5Pmm/gaS0qcLLgGt2OBaSk= 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=LcTRjjvU; arc=none smtp.client-ip=209.85.222.201 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="LcTRjjvU" Received: by mail-qk1-f201.google.com with SMTP id af79cd13be357-8e8950b3ee1so1615601085a.3 for ; Wed, 22 Apr 2026 23:28:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1776925722; x=1777530522; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=d2awcyUUlOZ7DiUll5yCRAkp5hrWVwnaXgkecEMdniQ=; b=LcTRjjvUmFlolRMK/sxv3m5TZYWG5Dp2F5oeRrsrj8SE6H7Ig9Zfs1eLJWsfuqM6sx Rorp/tq/T+1TwQVeaH0eGYrJGBGxyYqaBUI7YMfkEFlBv65aqaBn/41BaEN7O/Nm4mX4 sr1sIgL6fBJ7KMBp2BTzsfHxp50njZhTGiHSpp2cxScF331FEzoF8EDOZYwFQF9dsk2u 2awwFkKGqkpxV/+CMbPJZEV6yRbELYkWvQQ7q9Fzllgpn5Pr/zEajIN9Myy64wTQIVYf CtPvhRNtQPieIFG6By9F1OCMA4TdNAGaGeMch+AaKHfW9VjsX88LxE53d8+J2XUoEius b54A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776925722; x=1777530522; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=d2awcyUUlOZ7DiUll5yCRAkp5hrWVwnaXgkecEMdniQ=; b=FVybnc+ehPO8/8m3fEM4AFziKBntlthm0DTHplltxyEufC8ukq+5Q0qdhWYrNHbfgu iRMIeEUEsF19uTjTStKCW0xXOIgreLbyRl6s0lftmhbWsjVH0UDDEgfr306n7z8YTTN3 IZ6N+RhCDGRh/9Ygn8PiVIVSnKG/GkTjkZFktk5xWXhlmgNfrtsH8Gs5b/KmWfDV4kgy q2MFaKP4C+INfCjtveixSVRn9n4suQyjHi3OVDJ7yi9cfy4fkymBdwQeGg2PpLEoLZxm OMmiNXhgXatnsCrIzf2Bu0Y3IRVBgAz+OO82/1ZgVyR4YDSGzj25ksh6PJlJvQSDOMsq x4rA== X-Forwarded-Encrypted: i=1; AFNElJ+c0vgC7SrAeXszj9PzJOYkLRUxBYu2+FcqbPYJrdBHM0hMu6lINh6Il4pJhMV5mLg9jNW2V1c=@vger.kernel.org X-Gm-Message-State: AOJu0YzsoMlwKSvJslaY6BuHyaFrLzAT+GmHCOopzgqkb6wyz8lDr2vM Kh540Vp6Ca2GfGYqsd22E2qWuZzwZHBWtBcl9a//+2wgcmAqNbVKyz6YtB790Td4REwsUm7IO3H 8nGZgciTAqi1XjA== X-Received: from qknrd3.prod.google.com ([2002:a05:620a:8dc3:b0:8eb:1c73:20c7]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:a05:620a:4089:b0:8cd:9707:630e with SMTP id af79cd13be357-8e78f82ad1amr3834388785a.19.1776925722029; Wed, 22 Apr 2026 23:28:42 -0700 (PDT) Date: Thu, 23 Apr 2026 06:28:39 +0000 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.54.0.rc2.544.gc7ae2d5bb8-goog Message-ID: <20260423062839.2524324-1-edumazet@google.com> Subject: [PATCH net] net/sched: sch_choke: annotate data-races in choke_dump_stats() From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Jamal Hadi Salim , Jiri Pirko , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet Content-Type: text/plain; charset="UTF-8" choke_dump_stats() only runs with RTNL held. It reads fields that can be changed in qdisc fast path. Add READ_ONCE()/WRITE_ONCE() annotations. Fixes: edb09eb17ed8 ("net: sched: do not acquire qdisc spinlock in qdisc/class stats dump") Signed-off-by: Eric Dumazet Reviewed-by: Jamal Hadi Salim --- net/sched/sch_choke.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/net/sched/sch_choke.c b/net/sched/sch_choke.c index 94df8e741a979191a06885ad3ee813f12650ff3c..2875bcdb18a413075c795665e95f9dbbaac45962 100644 --- a/net/sched/sch_choke.c +++ b/net/sched/sch_choke.c @@ -229,7 +229,7 @@ static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch, /* Draw a packet at random from queue and compare flow */ if (choke_match_random(q, skb, &idx)) { - q->stats.matched++; + WRITE_ONCE(q->stats.matched, q->stats.matched + 1); choke_drop_by_idx(sch, idx, to_free); goto congestion_drop; } @@ -241,11 +241,13 @@ static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch, qdisc_qstats_overlimit(sch); if (use_harddrop(q) || !use_ecn(q) || !INET_ECN_set_ce(skb)) { - q->stats.forced_drop++; + WRITE_ONCE(q->stats.forced_drop, + q->stats.forced_drop + 1); goto congestion_drop; } - q->stats.forced_mark++; + WRITE_ONCE(q->stats.forced_mark, + q->stats.forced_mark + 1); } else if (++q->vars.qcount) { if (red_mark_probability(p, &q->vars, q->vars.qavg)) { q->vars.qcount = 0; @@ -253,11 +255,13 @@ static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch, qdisc_qstats_overlimit(sch); if (!use_ecn(q) || !INET_ECN_set_ce(skb)) { - q->stats.prob_drop++; + WRITE_ONCE(q->stats.prob_drop, + q->stats.prob_drop + 1); goto congestion_drop; } - q->stats.prob_mark++; + WRITE_ONCE(q->stats.prob_mark, + q->stats.prob_mark + 1); } } else q->vars.qR = red_random(p); @@ -272,7 +276,7 @@ static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch, return NET_XMIT_SUCCESS; } - q->stats.pdrop++; + WRITE_ONCE(q->stats.pdrop, q->stats.pdrop + 1); return qdisc_drop(skb, sch, to_free); congestion_drop: @@ -461,10 +465,12 @@ static int choke_dump_stats(struct Qdisc *sch, struct gnet_dump *d) { struct choke_sched_data *q = qdisc_priv(sch); struct tc_choke_xstats st = { - .early = q->stats.prob_drop + q->stats.forced_drop, - .marked = q->stats.prob_mark + q->stats.forced_mark, - .pdrop = q->stats.pdrop, - .matched = q->stats.matched, + .early = READ_ONCE(q->stats.prob_drop) + + READ_ONCE(q->stats.forced_drop), + .marked = READ_ONCE(q->stats.prob_mark) + + READ_ONCE(q->stats.forced_mark), + .pdrop = READ_ONCE(q->stats.pdrop), + .matched = READ_ONCE(q->stats.matched), }; return gnet_stats_copy_app(d, &st, sizeof(st)); -- 2.54.0.rc2.544.gc7ae2d5bb8-goog