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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 462AEC433E0 for ; Fri, 19 Jun 2020 00:01:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B93B208D5 for ; Fri, 19 Jun 2020 00:01:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=joelfernandes.org header.i=@joelfernandes.org header.b="cy8LU4gN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728053AbgFSAB6 (ORCPT ); Thu, 18 Jun 2020 20:01:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58764 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726001AbgFSAB6 (ORCPT ); Thu, 18 Jun 2020 20:01:58 -0400 Received: from mail-qv1-xf41.google.com (mail-qv1-xf41.google.com [IPv6:2607:f8b0:4864:20::f41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CE1FC06174E for ; Thu, 18 Jun 2020 17:01:58 -0700 (PDT) Received: by mail-qv1-xf41.google.com with SMTP id e2so3662231qvw.7 for ; Thu, 18 Jun 2020 17:01:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=RNchvC4tH2Tj4K3jgyuexvmGUcl61SJ/ygEHsSpC1MI=; b=cy8LU4gN5EMWqz2rD+681PTcDvGi0NtokQF1JnGdedhKjh7HV+2NeV7U6F1NvAWJ7A QenGDTy+fEKKwZFCU/PBkCALnDs3uLdWypWU8v+CrMLetqK+L43rwP75KaAqvcyCp/Sg kQmIZkd+7vZ0Qjr9gtzlUgONWZsqGsnGcybEw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=RNchvC4tH2Tj4K3jgyuexvmGUcl61SJ/ygEHsSpC1MI=; b=KXM2+jQH9hpCRAVvAvf7o3DCTS6ibn8pyuxbM3hH4NLGSclQdq6JJoExf3x0Yn3Bzb ztf8HMZ7mW7E+ViaO/6HqVQP9V7u8Wiyt0IeA0YBeerffNbRI/ASk+zEPLLFIS2IGOTJ qhbpwsXoOynULicH8deao0HbcxZu3HXSk5h5aw7cfK9WradxPcr7Ql3xrgfr9mcO2Q6s hYybPIOAJUAb9aGuAFp1OSYhhjySpTDxoKO7+JQ1Pd7kL8q7CimBhHMQvr2u8MOY5Rnk /ZA9wRKABa1VA6N4Gk5LYtGKQAEVWH4SlflNCrbGR46/Sy7TqWxJZNL/QGgJwq54KylR pwbg== X-Gm-Message-State: AOAM532JjulIqWmnlZFkR9iOF6gQGL4zyN052zdN25FEV0nGlGmCQH+q /jedzFmRcyLqyIEMEfUA6dgfJQ== X-Google-Smtp-Source: ABdhPJwlQKbcQQUzDdsZoGymkXo/pBXE0eYMdHpV8eExonBxpGTRc2ese8BIwCGXZuMM/eqMx76keg== X-Received: by 2002:a05:6214:1342:: with SMTP id b2mr6425412qvw.80.1592524917556; Thu, 18 Jun 2020 17:01:57 -0700 (PDT) Received: from localhost ([2620:15c:6:12:9c46:e0da:efbf:69cc]) by smtp.gmail.com with ESMTPSA id g5sm5271583qta.46.2020.06.18.17.01.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Jun 2020 17:01:57 -0700 (PDT) Date: Thu, 18 Jun 2020 20:01:56 -0400 From: Joel Fernandes To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, Davidlohr Bueso , Ingo Molnar , Josh Triplett , Lai Jiangshan , Marco Elver , Mathieu Desnoyers , rcu@vger.kernel.org, Steven Rostedt , "Uladzislau Rezki (Sony)" Subject: Re: [PATCH 6/7] rcutorture: Add support to get the number of wakeups of main GP kthread Message-ID: <20200619000156.GD40119@google.com> References: <20200618202955.4024-1-joel@joelfernandes.org> <20200618202955.4024-6-joel@joelfernandes.org> <20200618224058.GD2723@paulmck-ThinkPad-P72> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200618224058.GD2723@paulmck-ThinkPad-P72> Sender: rcu-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org On Thu, Jun 18, 2020 at 03:40:58PM -0700, Paul E. McKenney wrote: > On Thu, Jun 18, 2020 at 04:29:54PM -0400, Joel Fernandes (Google) wrote: > > This is useful to check for any improvements or degradation related to > > number of GP kthread wakeups during testing. > > > > Signed-off-by: Joel Fernandes (Google) > > This was a good way to collect the data for your testing, but > we can expect rcutorture to only do so much. ;-) np, I will push this one into a git tag for the next time I need it ;) thanks, - Joel > Thanx, Paul > > > --- > > kernel/rcu/Kconfig.debug | 1 + > > kernel/rcu/rcu.h | 2 ++ > > kernel/rcu/rcutorture.c | 23 ++++++++++++++++++++++- > > kernel/rcu/tree.c | 7 +++++++ > > 4 files changed, 32 insertions(+), 1 deletion(-) > > > > diff --git a/kernel/rcu/Kconfig.debug b/kernel/rcu/Kconfig.debug > > index 3cf6132a4bb9f..3323e3378af5a 100644 > > --- a/kernel/rcu/Kconfig.debug > > +++ b/kernel/rcu/Kconfig.debug > > @@ -50,6 +50,7 @@ config RCU_TORTURE_TEST > > select TASKS_RCU > > select TASKS_RUDE_RCU > > select TASKS_TRACE_RCU > > + select SCHEDSTATS > > default n > > help > > This option provides a kernel module that runs torture tests > > diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h > > index cf66a3ccd7573..7e867e81d9738 100644 > > --- a/kernel/rcu/rcu.h > > +++ b/kernel/rcu/rcu.h > > @@ -511,6 +511,7 @@ srcu_batches_completed(struct srcu_struct *sp) { return 0; } > > static inline void rcu_force_quiescent_state(void) { } > > static inline void show_rcu_gp_kthreads(void) { } > > static inline int rcu_get_gp_kthreads_prio(void) { return 0; } > > +static inline struct task_struct *rcu_get_main_gp_kthread(void) { return 0; } > > static inline void rcu_fwd_progress_check(unsigned long j) { } > > #else /* #ifdef CONFIG_TINY_RCU */ > > bool rcu_dynticks_zero_in_eqs(int cpu, int *vp); > > @@ -519,6 +520,7 @@ unsigned long rcu_exp_batches_completed(void); > > unsigned long srcu_batches_completed(struct srcu_struct *sp); > > void show_rcu_gp_kthreads(void); > > int rcu_get_gp_kthreads_prio(void); > > +struct task_struct *rcu_get_main_gp_kthread(void); > > void rcu_fwd_progress_check(unsigned long j); > > void rcu_force_quiescent_state(void); > > extern struct workqueue_struct *rcu_gp_wq; > > diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c > > index d0d265304d147..959a1f84d6904 100644 > > --- a/kernel/rcu/rcutorture.c > > +++ b/kernel/rcu/rcutorture.c > > @@ -23,6 +23,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -460,9 +461,29 @@ static void rcu_sync_torture_init(void) > > INIT_LIST_HEAD(&rcu_torture_removed); > > } > > > > +unsigned long rcu_gp_nr_wakeups; > > + > > +static void rcu_flavor_init(void) > > +{ > > + rcu_sync_torture_init(); > > + > > + /* Make sure schedstat is enabled for GP thread wakeup count. */ > > + force_schedstat_enabled(); > > + rcu_gp_nr_wakeups = rcu_get_main_gp_kthread()->se.statistics.nr_wakeups; > > +} > > + > > +static void rcu_flavor_cleanup(void) > > +{ > > + unsigned long now_nr = rcu_get_main_gp_kthread()->se.statistics.nr_wakeups; > > + > > + pr_alert("End-test: Cleanup: Total GP-kthread wakeups: %lu\n", > > + now_nr - rcu_gp_nr_wakeups); > > +} > > + > > static struct rcu_torture_ops rcu_ops = { > > .ttype = RCU_FLAVOR, > > - .init = rcu_sync_torture_init, > > + .init = rcu_flavor_init, > > + .cleanup = rcu_flavor_cleanup, > > .readlock = rcu_torture_read_lock, > > .read_delay = rcu_read_delay, > > .readunlock = rcu_torture_read_unlock, > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > > index c3bae7a83d792..a3a175feb310a 100644 > > --- a/kernel/rcu/tree.c > > +++ b/kernel/rcu/tree.c > > @@ -175,6 +175,13 @@ int rcu_get_gp_kthreads_prio(void) > > } > > EXPORT_SYMBOL_GPL(rcu_get_gp_kthreads_prio); > > > > +/* Retrieve RCU's main GP kthread task_struct */ > > +struct task_struct *rcu_get_main_gp_kthread(void) > > +{ > > + return rcu_state.gp_kthread; > > +} > > +EXPORT_SYMBOL_GPL(rcu_get_main_gp_kthread); > > + > > /* > > * Number of grace periods between delays, normalized by the duration of > > * the delay. The longer the delay, the more the grace periods between > > -- > > 2.27.0.111.gc72c7da667-goog > >