From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AACB8C43331 for ; Wed, 6 Jan 2021 16:57:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8B42C23134 for ; Wed, 6 Jan 2021 16:57:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727868AbhAFQ44 (ORCPT ); Wed, 6 Jan 2021 11:56:56 -0500 Received: from mail.kernel.org ([198.145.29.99]:56750 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727837AbhAFQ4x (ORCPT ); Wed, 6 Jan 2021 11:56:53 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2DF8D2313C; Wed, 6 Jan 2021 16:55:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1609952134; bh=5N4yy6vCgBYA88AYbYBNwRYZKoVb53QM2QFfeDuwqq0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Acm4zyoAS4r5/CWIZ+l6KnysOZ3clsALA5U9AaDUXh9lx1LQ2OfxGwepVOnuzs/dc WZ9P+VnJV45HjMvlG12NhraiUi+b89qUNOX4xdQLhj2gwW6KqJ/tWrOO0mwiZQbvtV vvWb604REDgjwcELwiqk5sTOHEOfIWjPQbLh1LRyBXUT2AQwG2pFV3Q4jZCFZokIb+ ZhrB6QkACXvDW+AFvs1R6wp4SfLbvq2iolWnCObhcPaMSQqL+2u7Z/+dPRg3a6jrQK 1bSvO1Q/vazfu5tKU+YL03G/wSE3LEsZbIVUGUy3EAsSqRjVgLn+jWdstRlsoB2czC D1YzbdyV5ELGw== From: paulmck@kernel.org To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 10/10] rcutorture: Add reader-side tests of polling grace-period API Date: Wed, 6 Jan 2021 08:55:31 -0800 Message-Id: <20210106165531.20697-10-paulmck@kernel.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20210106165511.GA20555@paulmck-ThinkPad-P72> References: <20210106165511.GA20555@paulmck-ThinkPad-P72> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Paul E. McKenney" This commit adds reader-side testing of the polling grace-period API. This testing verifies that a cookie obtained in an SRCU read-side critical section does not get a true return from poll_state_synchronize_srcu() within that same critical section. Link: https://lore.kernel.org/rcu/20201112201547.GF3365678@moria.home.lan/ Reported-by: Kent Overstreet Signed-off-by: Paul E. McKenney --- kernel/rcu/rcutorture.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 78ba95d..96d55f0 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1429,6 +1429,7 @@ rcutorture_loop_extend(int *readstate, struct torture_random_state *trsp, */ static bool rcu_torture_one_read(struct torture_random_state *trsp) { + unsigned long cookie; int i; unsigned long started; unsigned long completed; @@ -1444,6 +1445,8 @@ static bool rcu_torture_one_read(struct torture_random_state *trsp) WARN_ON_ONCE(!rcu_is_watching()); newstate = rcutorture_extend_mask(readstate, trsp); rcutorture_one_extend(&readstate, newstate, trsp, rtrsp++); + if (cur_ops->get_gp_state && cur_ops->poll_gp_state) + cookie = cur_ops->get_gp_state(); started = cur_ops->get_gp_seq(); ts = rcu_trace_clock_local(); p = rcu_dereference_check(rcu_torture_current, @@ -1480,6 +1483,13 @@ static bool rcu_torture_one_read(struct torture_random_state *trsp) } __this_cpu_inc(rcu_torture_batch[completed]); preempt_enable(); + if (cur_ops->get_gp_state && cur_ops->poll_gp_state) + WARN_ONCE(cur_ops->poll_gp_state(cookie), + "%s: Cookie check 3 failed %s(%d) %lu->%lu\n", + __func__, + rcu_torture_writer_state_getname(), + rcu_torture_writer_state, + cookie, cur_ops->get_gp_state()); rcutorture_one_extend(&readstate, 0, trsp, rtrsp); WARN_ON_ONCE(readstate & RCUTORTURE_RDR_MASK); // This next splat is expected behavior if leakpointer, especially -- 2.9.5