From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qv1-f74.google.com (mail-qv1-f74.google.com [209.85.219.74]) (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 A2E263C9420 for ; Wed, 8 Apr 2026 12:56:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775652998; cv=none; b=tO+ucO/3IIHtavAKEywp7vHCHuOnZtqNiOae5/pHulwORxvh7n5o+3HkpM3RYe6b/pVar1sU4cNUjvIL6YMhZRtp5PmV+Vngzd1x6r7PigxP3y9miBAqKv7eOOn/eCJKNAT7CXIrrpAmcmq3OQpWQIAYNfpX0FBuZMmfoo9qJoA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775652998; c=relaxed/simple; bh=K9d44KQDeEWHNSllzrUTy0gLgc056e+wl1b1hL3dSY8=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=gi87LhJc8Nsqp8d+87XtjGUDLLQ1kqzTDVl6+XwN+BO9ApL9tZCEamGi/a8TvFv+ltFKjeX2dGnfsoPKm3K+zBUUzQR9dV3StGUuk96zT2+74l2W822dRHVYxVZytAFT+Zmp5eKnGWeFYeOjOAI+h9cLHWWrKQaUqKMWFCPUehM= 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=UlLVM/wj; arc=none smtp.client-ip=209.85.219.74 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="UlLVM/wj" Received: by mail-qv1-f74.google.com with SMTP id 6a1803df08f44-8a8ea3f1becso124426446d6.0 for ; Wed, 08 Apr 2026 05:56:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1775652995; x=1776257795; 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=Qp/OLL06Dqe7i66SOntwCo2pOiy130tu28jOnMwLnlc=; b=UlLVM/wjcR5uy7nkVqtLe2a9ZbmizvA/KdF9plfDDD6Ln/pIa5V1kHZTl2oYtjhw2B DJ9zsqaROa26aiD6H6e1DYtLuV2ZXQlveErOwyuS8579s5Lz3bUtwvEzp5VjoEXYtCDO wC4vyWQor2NMKLppyuQ6uAmRMAgtbbDMg0jvdJ0I1xMg7yn6Oms2Cb3LijtQNVupmhry oSxPzAQtBRmE78nNpZiCHS31BgCxMqoRc+P4SR4lxwu+MMqjbiqRJQILA2VpB1zjlcIz JvAr+doxUunI9O4HP387Oo2SrlEfdOHXNBFqyu2A1NYEOj5Uc8+mxZxsQIDov5bOaJWa dVGA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775652995; x=1776257795; 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=Qp/OLL06Dqe7i66SOntwCo2pOiy130tu28jOnMwLnlc=; b=PcDcZe4qW/fk0Ltuo7ICiEFwVdlCLReCD1trQNWirdnTp1j9b5zwCzGlmxSS/jlHx6 j0j9DpfJkqLRFD2ZRiAQYGffrdcn0BzFfJ/Sev9lCXoPfLAM24/IusdY0y/q+56rKaUz qcZSankpUDvmDo0yU4Teb0Q7PsT7nYujPHd8a+drgiWU7dA3A+XMxDwj1tfzygak1sMd 0LPk9ngwrKn7PMfhETraK6CjkmTiWeTnciJxF9/p7pgTdotugTEG4+0pxrPl2dSWgZm1 N/C/wnf7oKiZ4uzwCw63xn/X1Ssl1YtH93mthash683AcwZaO+25S6IrdV0SYiqWzxnv jAYA== X-Forwarded-Encrypted: i=1; AJvYcCU4PVP/ZOwh22XyYzA3QE5e8dowrHGqV/z2MhecPL9Q0Iu/7m16pNNAa//gmIW+Wy7BJZk94k8=@vger.kernel.org X-Gm-Message-State: AOJu0Yz9+7fFKtt8GbzelJGi3dcG3VDymbES9rqFNVcS3NFUR4du36kg AWXdHooFxL2Dl3TafW8TY3UlbtOWdtvAEbHcxmzMcD0I9RO2Cdgbv9oCxs4xzXkDN7UPyvz7vOR kIBNSt3eaO4ScKQ== X-Received: from qvboe2.prod.google.com ([2002:a05:6214:4302:b0:896:f72b:27fe]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:ad4:4eef:0:b0:899:eba1:3c14 with SMTP id 6a1803df08f44-8a7025b7992mr362485116d6.18.1775652995403; Wed, 08 Apr 2026 05:56:35 -0700 (PDT) Date: Wed, 8 Apr 2026 12:56:08 +0000 In-Reply-To: <20260408125611.3592751-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260408125611.3592751-1-edumazet@google.com> X-Mailer: git-send-email 2.53.0.1213.gd9a14994de-goog Message-ID: <20260408125611.3592751-13-edumazet@google.com> Subject: [PATCH net-next 12/15] 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 , Kuniyuki Iwashima , 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, reading 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 --- 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 cd0785ad8e74314e6d5c88144ffcf64f286e02dd..73d3e673dc7b16cf2b9ac1d622da280c2ceb064a 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)); -- 2.53.0.1213.gd9a14994de-goog