From nobody Tue Oct 7 15:01:46 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A46BF28DB5D; Wed, 9 Jul 2025 10:43:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752057799; cv=none; b=f+qzLwRWa5/xFrka2OQ5O9TzvXqp8cdihdeXtjeV1kUG2xINx2kFpvMV0wDoCNUxU+/vxGx9hkaZzNjPY5uTE6h9CY30d0zuvb8IcU3olFRTMi/Xch0QNKCUibrS59AUnq8piaMJgHanGaUCN7/FSPAtGMBJK4ulsW8yFc4hfWA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752057799; c=relaxed/simple; bh=6qbMqWsJuVvvTWS+gO5LrsfTdlSB6Hd/6dmtTEFxq1U=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=hmh+ZSNGcq1ixGYuoUcr43aA0dX2sQfdykaf64eU6eVUKZlJPybn33SRfXbPZzhnNMlD2BkyvVYnKYozPNDy096+IYWzDOfIVVYAJqHu+bynmru6BXKst9LgA1KPv92e+r6ff5G2lPoAiXrFFlzPnfpMSLPq7U+nWxGQH/6EsPk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c+oAG77J; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="c+oAG77J" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6DC77C4CEEF; Wed, 9 Jul 2025 10:43:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752057799; bh=6qbMqWsJuVvvTWS+gO5LrsfTdlSB6Hd/6dmtTEFxq1U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c+oAG77JmwfOmK7IRxWVcaSrZQkGT6KydkHcPzp9W1X2dYdc4UXUy1TKjlBiu6N5p dB/fpKXugYnN5ARG67To28K+FK8q9anHg2DWFqgYvv7IQAoUce1pUT/Wn5Cw1F9Y4S dtmRwvL1wtVxMt7GPOmoa8ZHbnMgdfN4BymRxQc1/+xPX+IDxoVlpaY3VWrP7buQen 5+AxKP2GVBVImdrziQkCIZSkJab6JDGqUQcZcjYkAeB50OBz54sCsV2CA6ZIX9fdYC ZPhpAFnpuf4qweDkGgr2lyyL3rSOEsTzW2ctSGAY+9OXKx8+C2oonbCErOhhYFA9UD UcX7mex8U2OKQ== From: neeraj.upadhyay@kernel.org To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, paulmck@kernel.org, joelagnelf@nvidia.com, frederic@kernel.org, boqun.feng@gmail.com, urezki@gmail.com, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, qiang.zhang1211@gmail.com, neeraj.iitr10@gmail.com, neeraj.upadhyay@amd.com, "Neeraj Upadhyay (AMD)" Subject: [PATCH rcu 08/15] rcutorture: Check for no up/down readers at task level Date: Wed, 9 Jul 2025 16:12:08 +0530 Message-Id: <20250709104215.15562-9-neeraj.upadhyay@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20250709104215.15562-1-neeraj.upadhyay@kernel.org> References: <20250709104215.15562-1-neeraj.upadhyay@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Paul E. McKenney" The design of testing of up/down readers such as srcu_down_read() and srcu_up_read() assumes that these are tested only by the rcu_torture_updown() kthread, and never by the rcu_torture_reader() kthread. Because we all know which road is paved with good intentions, this commit adds WARN_ON_ONCE() to verify that things are going to plan. Signed-off-by: Paul E. McKenney Signed-off-by: Neeraj Upadhyay (AMD) --- kernel/rcu/rcutorture.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index f773d4f8f2ae..10f3cc4861ee 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -2232,6 +2232,7 @@ rcutorture_loop_extend(int *readstate, bool insoftirq= , struct torture_random_sta i =3D ((i | (i >> 3)) & RCUTORTURE_RDR_MAX_LOOPS) + 1; for (j =3D 0; j < i; j++) { mask =3D rcutorture_extend_mask(*readstate, trsp); + WARN_ON_ONCE(mask & RCUTORTURE_RDR_UPDOWN); rcutorture_one_extend(readstate, mask, insoftirq, trsp, &rtrsp[j]); } return &rtrsp[j]; @@ -2368,6 +2369,7 @@ static bool rcu_torture_one_read(struct torture_rando= m_state *trsp, long myid) WARN_ON_ONCE(!rcu_is_watching()); init_rcu_torture_one_read_state(&rtors, trsp); newstate =3D rcutorture_extend_mask(rtors.readstate, trsp); + WARN_ON_ONCE(newstate & RCUTORTURE_RDR_UPDOWN); rcutorture_one_extend(&rtors.readstate, newstate, myid < 0, trsp, rtors.r= trsp++); if (!rcu_torture_one_read_start(&rtors, trsp, myid)) { rcutorture_one_extend(&rtors.readstate, 0, myid < 0, trsp, rtors.rtrsp); --=20 2.40.1