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 1C9C6C433E6 for ; Mon, 21 Dec 2020 19:30:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E149022B4B for ; Mon, 21 Dec 2020 19:30:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726810AbgLUT3s (ORCPT ); Mon, 21 Dec 2020 14:29:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:58372 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726167AbgLUT3r (ORCPT ); Mon, 21 Dec 2020 14:29:47 -0500 Date: Mon, 21 Dec 2020 11:29:06 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1608578946; bh=vT38HP0xAEUCHbHEYa3RfIX36aUGrZmaXWBNf2WG7Ik=; h=From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=bZ9T4zESLVSijSrCN0uzFwy+nmradO5xy7ZE+ODA/8JRdV9XY6q8t90+7NHn/TgTL ytUp491ntjomNWMi2TyM0KAf5Rrg7FLaez23SGmmisWnust3TMKqrcv3dISbsGruX6 THLPSiQzJIqoewaaplGKQq+CWljX+Ww7fNWpmLLZ9juk8EdluZ68xW7YC8g03vyrC9 by5a2KKMy2J1VbGJd8M6a6VeS/gdBEVW1XtGGP6QLmN+0lh55Jq6OQR/TKA4CWA/gX xBfpGHsMpQYujKwpWIKYym7yALnASHm/C+xbq87pax/4iidnAKukg+EU+8aANdValy voIRxn45aaZjQ== 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: <20201221192906.GX2657@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> <20201221171805.GW2657@paulmck-ThinkPad-P72> <20201221184539.GA24895@pc638.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201221184539.GA24895@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 07:45:39PM +0100, Uladzislau Rezki wrote: > On Mon, Dec 21, 2020 at 09:18:05AM -0800, Paul E. McKenney wrote: > > 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); > That is fine! We can output the name instead of executed counter. > Doing so makes it completely clear who triggers the callback. And we also need to make it not trigger when CONFIG_PROVE_RCU=n. While in the area, we might as well leave anything that is needed only by CONFIG_PROVE_RCU=y undefined when CONFIG_PROVE_RCU=n. How about the following? Thanx, Paul ------------------------------------------------------------------------ commit f7a1ac0d3504e0518745da7f98573c1b13587f3e 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) [ paulmck: Handle CONFIG_PROVE_RCU=n and identify test cases' callbacks. ] Signed-off-by: Paul E. McKenney diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index 3660755..af7c194 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -1224,6 +1224,82 @@ void show_rcu_tasks_gp_kthreads(void) } #endif /* #ifndef CONFIG_TINY_RCU */ +#ifdef CONFIG_PROVE_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; +} + +static void rcu_tasks_initiate_self_tests(void) +{ + 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_PROVE_RCU */ +static void rcu_tasks_initiate_self_tests(void) { } +#endif /* #else #ifdef CONFIG_PROVE_RCU */ + void __init rcu_init_tasks_generic(void) { #ifdef CONFIG_TASKS_RCU @@ -1237,6 +1313,9 @@ void __init rcu_init_tasks_generic(void) #ifdef CONFIG_TASKS_TRACE_RCU rcu_spawn_tasks_trace_kthread(); #endif + + // Run the self-tests. + rcu_tasks_initiate_self_tests(); } #else /* #ifdef CONFIG_TASKS_RCU_GENERIC */