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=-17.5 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_SANE_1 autolearn=ham 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 17342C433DB for ; Mon, 21 Dec 2020 17:19:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D80DE22BF3 for ; Mon, 21 Dec 2020 17:19:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726502AbgLURSs (ORCPT ); Mon, 21 Dec 2020 12:18:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:60026 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725930AbgLURSr (ORCPT ); Mon, 21 Dec 2020 12:18:47 -0500 Date: Mon, 21 Dec 2020 09:18:05 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1608571086; bh=hRwqD0VhUV7p15cXHAo2g5jrugv7tZUYeRciom14PMk=; h=From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=ODePjfM8X9V8+1wVOx9kMQogydBWyRw995wPS0/pi3UXMWLJktWZrwFwFS1PU6QIL MJMPLRH/ly0qx+dPhk80ZB/CMytMJoYx42IrzJU2ouWnIVE8nQPrfH91p2O7hU3HfW 6WpaylgNa6zD5kscGTQBtSVUJQkxh69YKGYqWuAwQ/28/bc6h2ulyP3XDska429QOR Z5yQ2KMWk11pBIIQn2iImmDsgzO+YG5BzTMbNMUK5CAHPix7K9l1w4Mt9HDt9QJt+/ JrPtPSROyE0wfh46Bgx7u3JF9YPDiQ0+dzSyIcwcSKcn2GH3eg8FwH0LatQjktNOU1 VpjvRgEdMrAAg== From: "Paul E. McKenney" To: Uladzislau Rezki Cc: LKML , RCU , Michael Ellerman , Andrew Morton , Daniel Axtens , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Peter Zijlstra , Michal Hocko , Thomas Gleixner , "Theodore Y . Ts'o" , Sebastian Andrzej Siewior , Oleksiy Avramchenko Subject: Re: [PATCH 2/2] rcu-tasks: add RCU-tasks self tests Message-ID: <20201221171805.GW2657@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20201209202732.5896-1-urezki@gmail.com> <20201209202732.5896-2-urezki@gmail.com> <20201216154959.GA2408@pc638.lan> <20201216232955.GO2657@paulmck-ThinkPad-P72> <20201221153809.GA24756@pc638.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201221153809.GA24756@pc638.lan> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 21, 2020 at 04:38:09PM +0100, Uladzislau Rezki wrote: > On Wed, Dec 16, 2020 at 03:29:55PM -0800, Paul E. McKenney wrote: > > On Wed, Dec 16, 2020 at 04:49:59PM +0100, Uladzislau Rezki wrote: [ . . . ] > > > 2.20.1 > > > > Again, much improved! > > > See below the v3 version. I hope i fixed all comments :) > > >From 06f7adfd84cbb1994d0e2693ee9dcdfd272a9bd0 Mon Sep 17 00:00:00 2001 > From: "Uladzislau Rezki (Sony)" > Date: Wed, 9 Dec 2020 21:27:32 +0100 > Subject: [PATCH v3 1/1] rcu-tasks: Add RCU-tasks self tests > > This commit adds self tests for early-boot use of RCU-tasks grace periods. > It tests all three variants (Rude, Tasks, and Tasks Trace) and covers > both synchronous (e.g., synchronize_rcu_tasks()) and asynchronous (e.g., > call_rcu_tasks()) grace-period APIs. > > Self-tests are run only in kernels built with CONFIG_PROVE_RCU=y. > > Signed-off-by: Uladzislau Rezki (Sony) Much better! I pulled this in, but made one small additional change. Please let me know if this is problematic. Thanx, Paul ------------------------------------------------------------------------ commit 93372198b5c9efdfd288aa3b3ee41c1f90866886 Author: Uladzislau Rezki (Sony) Date: Wed Dec 9 21:27:32 2020 +0100 rcu-tasks: Add RCU-tasks self tests This commit adds self tests for early-boot use of RCU-tasks grace periods. It tests all three variants (Rude, Tasks, and Tasks Trace) and covers both synchronous (e.g., synchronize_rcu_tasks()) and asynchronous (e.g., call_rcu_tasks()) grace-period APIs. Self-tests are run only in kernels built with CONFIG_PROVE_RCU=y. Signed-off-by: Uladzislau Rezki (Sony) Signed-off-by: Paul E. McKenney diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index 3660755..35a2cd5 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -1224,6 +1224,40 @@ void show_rcu_tasks_gp_kthreads(void) } #endif /* #ifndef CONFIG_TINY_RCU */ +struct rcu_tasks_test_desc { + struct rcu_head rh; + const char *name; + bool notrun; +}; + +static struct rcu_tasks_test_desc tests[] = { + { + .name = "call_rcu_tasks()", + /* If not defined, the test is skipped. */ + .notrun = !IS_ENABLED(CONFIG_TASKS_RCU), + }, + { + .name = "call_rcu_tasks_rude()", + /* If not defined, the test is skipped. */ + .notrun = !IS_ENABLED(CONFIG_TASKS_RUDE_RCU), + }, + { + .name = "call_rcu_tasks_trace()", + /* If not defined, the test is skipped. */ + .notrun = !IS_ENABLED(CONFIG_TASKS_TRACE_RCU) + } +}; + +static void test_rcu_tasks_callback(struct rcu_head *rhp) +{ + struct rcu_tasks_test_desc *rttd = + container_of(rhp, struct rcu_tasks_test_desc, rh); + + pr_info("Callback from %s invoked.\n", rttd->name); + + rttd->notrun = true; +} + void __init rcu_init_tasks_generic(void) { #ifdef CONFIG_TASKS_RCU @@ -1237,7 +1271,45 @@ void __init rcu_init_tasks_generic(void) #ifdef CONFIG_TASKS_TRACE_RCU rcu_spawn_tasks_trace_kthread(); #endif + + // Run the self-tests. + if (IS_ENABLED(CONFIG_PROVE_RCU)) { + pr_info("Running RCU-tasks wait API self tests\n"); +#ifdef CONFIG_TASKS_RCU + synchronize_rcu_tasks(); + call_rcu_tasks(&tests[0].rh, test_rcu_tasks_callback); +#endif + +#ifdef CONFIG_TASKS_RUDE_RCU + synchronize_rcu_tasks_rude(); + call_rcu_tasks_rude(&tests[1].rh, test_rcu_tasks_callback); +#endif + +#ifdef CONFIG_TASKS_TRACE_RCU + synchronize_rcu_tasks_trace(); + call_rcu_tasks_trace(&tests[2].rh, test_rcu_tasks_callback); +#endif + } +} + +static int rcu_tasks_verify_self_tests(void) +{ + int ret = 0; + int i; + + for (i = 0; i < ARRAY_SIZE(tests); i++) { + if (!tests[i].notrun) { // still hanging. + pr_err("%s has been failed.\n", tests[i].name); + ret = -1; + } + } + + if (ret) + WARN_ON(1); + + return ret; } +late_initcall(rcu_tasks_verify_self_tests); #else /* #ifdef CONFIG_TASKS_RCU_GENERIC */ static inline void rcu_tasks_bootup_oddness(void) {}