From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f181.google.com (mail-pl1-f181.google.com [209.85.214.181]) (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 58ABD3E714C for ; Thu, 7 May 2026 10:20:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778149221; cv=none; b=tNxCqrB9oYUi5iWVGI2CLHGimIFs1m64Uf2CEYckcKUN9KWCatRf3IH/Oz+gwPWoRqsuo7OLv+Y2yNSZuIDs6SLQ0EKD717YS8q4ugbVMgDtXX7hXm9XCOf+yrOgt2dMdbTLQk89gWjJHvNeRNY641qucbhbeLBNQJ9olH8VR+w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778149221; c=relaxed/simple; bh=pTIS3ddteKk8VSJJdYgyLW3RXEMjDMZdMeaTc7I0pkM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Wdbp2jJSltcekDnWm+av/S90uFRs+Me0mTRyoNf0QVI71Hgkyp4Xy5k1dAoR5gsOB0tzDS4SKLEQdOFMDVUQO+aIrfX4UfFl8/RXMtcEwwr3Y860R6m9/tWIfCzLwONqeLIGEjMKE1EARH1AzzD9IN3mkgLxKHdscNH4FqeJwZA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=ceOPKJEz; arc=none smtp.client-ip=209.85.214.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ceOPKJEz" Received: by mail-pl1-f181.google.com with SMTP id d9443c01a7336-2ab46931cf1so12855255ad.0 for ; Thu, 07 May 2026 03:20:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1778149218; x=1778754018; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=NGpQTvYvqnOwNGJCeLIE5VPDvaD2U3g1tZqZ1BVFSQk=; b=ceOPKJEztE0Dy8vu6gwu/zO+oKuWv49acEkStOBhD+F2HYDHM7i8lBnP5j5ENEE53X qiIuun/KMKvtebN3mm7x4hQuYWW2VbDHta2FH87b66urEqmPqb9opp6D5tJi8zyyrxf6 w2stZJaYY0P0uafjt0cppAlkgZ2yzjuIKs0qSJt7HCdJEVY8QCkLWSq9ZJ05ixhSF/pS q8b88PMil8q/RIfCd3mu2xRjYPosqwg/ZuTYz3TwelqGCh/3m7aelChgohdXoF4/uu2J J5ecywdAVnglIxDuOx5xG1FyXvAJu0D9NuDxhxVTvLqunpc2pvSBUAHMhl5a8GsE0gBh LDAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778149218; x=1778754018; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=NGpQTvYvqnOwNGJCeLIE5VPDvaD2U3g1tZqZ1BVFSQk=; b=dwk1ugD0U6x80daxN1X/sgRLTVmlNufvknuWW7T3ymmWPeD1fRzhBU2YNiYHiRKzAZ lOsvA3AKcBkz1CKSaK6iDOqigCWvjlIZRZxE+TGXG8RxfK1KH7BO9SGNE4N5V3JfOAZ5 RlAPFaIdScuaPOUxxNr/FJFw4HyZFTCfEqMZfDqd3eY5WlC72KgNuW4cLNHpX7bmIPCV J073geXdPNJNqRLgmt1PQxLDs4H1e/iePMoNtE7eUQb0pKN2aDT2tP0ErQz5o1uSg+XP CJrEXK7kXUguxG9LArGyKoDx7J3yaI4mkXlhnB4OmS85HtVjK1/DzOJUInZsHsUWIH9p /5ng== X-Forwarded-Encrypted: i=1; AFNElJ8bPJ9GLrU9IOrPHlzNJ73wMR2JRjDLKxJaAVW6q3Svnpy3/DhMRq/uwX+tIQ6Y2Noh0zx1lkhAvXsLbV8=@vger.kernel.org X-Gm-Message-State: AOJu0YzqgrJR6coz2GyL2utNItEgUDL7iqaUQv7IOwvnB8C2bqa1Rd7C LzGNQrkSzn08Yu4Y+eBwBLK1oxclZEaxZDo7xOyQWuaqjo7T/MI2lwpvrbmxsnT5+2qwVw== X-Gm-Gg: AeBDievYs9uu/dBxk3GBy50tFle8DYdBCG7ZZtBpllR/L3diguQvGHFSMzSCvg7/Ffo 2/2GF+vwUfKQX7+1sUSscg5M5PBE5bW+hUGLzYMtfkgHp5R1pTkU9sYkNlyCxB5WDmhsyR9u98L bqzWDRIpf++SyuGUCA2qW0IDESQ96+3sOB2ePaliTOEk9HM1EJvmm+jU75xtiqWPC0wnHhWvl+z 0OJ95KqVWAPabymNri4/sdtbKsMWc9De0xYce30U6+tSSRqIJsqUDdwMEF1dpmFYwidU/cdplDc 5O89/rus6MrEoNRQ4pnxlRdGNXkOHmMJ5kfKjVldkvEklMfKYwz/3crV266oZuqW0AvZ6rjH7l1 QVDQdEyeWN4+daXQWsPPXS1L8iq40pGlhIDVLj1L/BpdPnLKMNfREHwGTaOwucxW9ZS5dgt9El3 nlo7AWOJhjMBn+0G1sqzZJRqzCR+FyKw5w1TQTOUo= X-Received: by 2002:a17:902:ce0c:b0:2aa:e47d:e3b with SMTP id d9443c01a7336-2babbcf5c72mr23067595ad.0.1778149218103; Thu, 07 May 2026 03:20:18 -0700 (PDT) Received: from vini ([2401:4900:8fc9:edb:b9ff:550d:d955:a799]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2baba80ac1esm20431505ad.0.2026.05.07.03.20.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 May 2026 03:20:17 -0700 (PDT) From: Vineet Agarwal To: netdev@vger.kernel.org Cc: jhs@mojatatu.com, jiri@resnulli.us, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, linux-kernel@vger.kernel.org, Vineet Agarwal Subject: [PATCH] net/sched: sch_dualpi2: annotate lockless accesses in dualpi2_dump_stats() Date: Thu, 7 May 2026 15:49:30 +0530 Message-ID: <20260507102005.263436-1-agarwal.vineet2006@gmail.com> X-Mailer: git-send-email 2.54.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit dualpi2_dump_stats() is called without holding qdisc lock. Several statistics fields are concurrently updated from enqueue and dequeue paths while being read locklessly from dualpi2_dump_stats(). Annotate these accesses with READ_ONCE(). Signed-off-by: Vineet Agarwal --- net/sched/sch_dualpi2.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/net/sched/sch_dualpi2.c b/net/sched/sch_dualpi2.c index 241e6a46bd00..fd8d505b4688 100644 --- a/net/sched/sch_dualpi2.c +++ b/net/sched/sch_dualpi2.c @@ -1046,14 +1046,13 @@ static int dualpi2_dump_stats(struct Qdisc *sch, struct gnet_dump *d) struct dualpi2_sched_data *q = qdisc_priv(sch); struct tc_dualpi2_xstats st = { .prob = READ_ONCE(q->pi2_prob), - .packets_in_c = q->packets_in_c, - .packets_in_l = q->packets_in_l, - .maxq = q->maxq, - .ecn_mark = q->ecn_mark, - .credit = q->c_protection_credit, - .step_marks = q->step_marks, - .memory_used = q->memory_used, - .max_memory_used = q->max_memory_used, + .packets_in_c = READ_ONCE(q->packets_in_c), + .packets_in_l = READ_ONCE(q->packets_in_l), + .maxq = READ_ONCE(q->maxq), + .ecn_mark = READ_ONCE(q->ecn_mark), + .step_marks = READ_ONCE(q->step_marks), + .memory_used = READ_ONCE(q->memory_used), + .max_memory_used = READ_ONCE(q->max_memory_used), .memory_limit = q->memory_limit, }; u64 qc, ql; -- 2.54.0