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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6AF2CC43334 for ; Tue, 12 Jul 2022 20:27:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231566AbiGLU1U (ORCPT ); Tue, 12 Jul 2022 16:27:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230311AbiGLU1S (ORCPT ); Tue, 12 Jul 2022 16:27:18 -0400 Received: from mail-il1-x12e.google.com (mail-il1-x12e.google.com [IPv6:2607:f8b0:4864:20::12e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 931B5C9239 for ; Tue, 12 Jul 2022 13:27:17 -0700 (PDT) Received: by mail-il1-x12e.google.com with SMTP id k1so5563178ilu.1 for ; Tue, 12 Jul 2022 13:27:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=zjw9e2+BSrR9+K/ZWOZ6b/ucoDYMrW7ATyZiGWZTTLQ=; b=WyxoXOcNASfPXCpxu80aIe67MG2WfPDdSzchvtcVMZLEL6I19PW95L2sD3z5qU5tzi 0wnHOysEsX3RZC9Qf5/gLbyzB/OItpHMnDAbLNCzjfiXc4d/ER0kX2tBJNoMAECDLo7v vhXZeREMTfY3YsxFxwMpctGCUTxhyNW0C7t6s= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=zjw9e2+BSrR9+K/ZWOZ6b/ucoDYMrW7ATyZiGWZTTLQ=; b=AvB/a5seSwHzRkrCucwsmBr7zKquMyKRJ7gzHDTQk43odCBmSLB1fWUdfSUNQQmZAW wsmFSTKFpYf8k8L6gYs+AFevalj4dagRUed7eKfnWV1jZqKP492ngbmm9Bxt3krbYFCk QqYyuOVdiu00axLBdeWDIscLzlZqYbHwrBPdxwldFrWQUWuSzz8dXl8CcT38V3i1PZIb zhuvcx5eMBRJAkmUQs93T93eBO7MfsXqodcvOwsmEdtdbjSpAB3ZXGELBI//Va0AqtW4 guv30PnpiNjs/w1fz41liSV/KXgCjIZBuZTcjf5olz6oZeHnNxyZmZcxZoMgi/QmHMsk m/Jg== X-Gm-Message-State: AJIora+3dyujuxny3dVEpjUt2p+yLAOz1l+UK2EN3Otd8l+dW6wXjqnL 8DBTkbEGKw0myGHypsUZVooe0txqHvsltFx+tXiu+g== X-Google-Smtp-Source: AGRyM1tom2lOE519sJVOZZgRNGq6HZvJ1iE6r4NPRrm6eWJhPbwKI8D1VoG2Y2FP1ECrlpz+WO/pwhN7SJqg7ua+ZEE= X-Received: by 2002:a05:6e02:219d:b0:2dc:41c2:a1f3 with SMTP id j29-20020a056e02219d00b002dc41c2a1f3mr14267281ila.79.1657657636956; Tue, 12 Jul 2022 13:27:16 -0700 (PDT) MIME-Version: 1.0 References: <20220622225102.2112026-1-joel@joelfernandes.org> <20220622225102.2112026-8-joel@joelfernandes.org> <20220626041327.GN1790663@paulmck-ThinkPad-P17-Gen-1> <20220708230600.GC1790663@paulmck-ThinkPad-P17-Gen-1> In-Reply-To: <20220708230600.GC1790663@paulmck-ThinkPad-P17-Gen-1> From: Joel Fernandes Date: Tue, 12 Jul 2022 16:27:05 -0400 Message-ID: Subject: Re: [PATCH v2 6/8] rcuscale: Add test for using call_rcu_lazy() to emulate kfree_rcu() To: "Paul E. McKenney" Cc: rcu , LKML , Rushikesh S Kadam , "Uladzislau Rezki (Sony)" , Neeraj upadhyay , Frederic Weisbecker , Steven Rostedt , vineeth@bitbyteword.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ah, with all the threads, I missed this one :(. Sorry about that. On Fri, Jul 8, 2022 at 7:06 PM Paul E. McKenney wrote: > > Currently I added a test like the following which adds a new torture type, my > > thought was to stress the new code to make sure nothing crashed or hung the > > kernel. That is working well except I don't exactly understand the total-gps > > print showing 0, which the other print shows 1188 GPs. I'll go dig into that > > tomorrow.. thanks! > > > > The print shows > > TREE11 ------- 1474 GPs (12.2833/s) [rcu_lazy: g0 f0x0 total-gps=0] > > TREE11 no success message, 7 successful version messages > > Nice!!! It is very good to see you correctly using the rcu_torture_ops > facility correctly! > > And this could be good for your own testing, and I am happy to pull it > in for that purpose (given it being fixed, having a good commit log, > and so on). After all, TREE10 is quite similar -- not part of CFLIST, > but useful for certain types of focused testing. > > However, it would be very good to get call_rcu_lazy() testing going > more generally, and in particular in TREE01 where offloading changes > dynamically. A good way to do this is to add a .call_lazy() component > to the rcu_torture_ops structure, and check for it in a manner similar > to that done for the .deferred_free() component. Including adding a > gp_normal_lazy module parameter. This would allow habitual testing > on a few scenarios and focused lazy testing on all of them via the > --bootargs parameter. Ok, if you don't mind I will make this particular enhancement to the torture test in a future patchset, since I kind of decided on doing v3 with just fixes to what I have and more testing. Certainly happy to enhance these tests in a future version. > On the total-gps=0, the usual suspicion would be that the lazy callbacks > never got invoked. It looks like you were doing about a two-minute run, > so maybe a longer run? Though weren't they supposed to kick in at 15 > seconds or so? Or did this value of zero come about because this run > used exactly 300 grace periods? It was zero because it required the RCU_FLAVOR torture type, where as my torture type was lazy. Adding RCU_LAZY_FLAVOR to the list fixed it :) Thanks! - Joel > > diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c > > index 7120165a9342..cc6b7392d801 100644 > > --- a/kernel/rcu/rcutorture.c > > +++ b/kernel/rcu/rcutorture.c > > @@ -872,6 +872,64 @@ static struct rcu_torture_ops tasks_rude_ops = { > > > > #endif // #else #ifdef CONFIG_TASKS_RUDE_RCU > > > > +#ifdef CONFIG_RCU_LAZY > > + > > +/* > > + * Definitions for lazy RCU torture testing. > > + */ > > +unsigned long orig_jiffies_till_flush; > > + > > +static void rcu_sync_torture_init_lazy(void) > > +{ > > + rcu_sync_torture_init(); > > + > > + orig_jiffies_till_flush = rcu_lazy_get_jiffies_till_flush(); > > + rcu_lazy_set_jiffies_till_flush(50); > > +} > > + > > +static void rcu_lazy_cleanup(void) > > +{ > > + rcu_lazy_set_jiffies_till_flush(orig_jiffies_till_flush); > > +} > > + > > +static struct rcu_torture_ops rcu_lazy_ops = { > > + .ttype = RCU_LAZY_FLAVOR, > > + .init = rcu_sync_torture_init_lazy, > > + .cleanup = rcu_lazy_cleanup, > > + .readlock = rcu_torture_read_lock, > > + .read_delay = rcu_read_delay, > > + .readunlock = rcu_torture_read_unlock, > > + .readlock_held = torture_readlock_not_held, > > + .get_gp_seq = rcu_get_gp_seq, > > + .gp_diff = rcu_seq_diff, > > + .deferred_free = rcu_torture_deferred_free, > > + .sync = synchronize_rcu, > > + .exp_sync = synchronize_rcu_expedited, > > + .get_gp_state = get_state_synchronize_rcu, > > + .start_gp_poll = start_poll_synchronize_rcu, > > + .poll_gp_state = poll_state_synchronize_rcu, > > + .cond_sync = cond_synchronize_rcu, > > + .call = call_rcu_lazy, > > + .cb_barrier = rcu_barrier, > > + .fqs = rcu_force_quiescent_state, > > + .stats = NULL, > > + .gp_kthread_dbg = show_rcu_gp_kthreads, > > + .check_boost_failed = rcu_check_boost_fail, > > + .stall_dur = rcu_jiffies_till_stall_check, > > + .irq_capable = 1, > > + .can_boost = IS_ENABLED(CONFIG_RCU_BOOST), > > + .extendables = RCUTORTURE_MAX_EXTEND, > > + .name = "rcu_lazy" > > +}; > > + > > +#define LAZY_OPS &rcu_lazy_ops, > > + > > +#else // #ifdef CONFIG_RCU_LAZY > > + > > +#define LAZY_OPS > > + > > +#endif // #else #ifdef CONFIG_RCU_LAZY > > + > > > > #ifdef CONFIG_TASKS_TRACE_RCU > > > > @@ -3145,7 +3203,7 @@ rcu_torture_init(void) > > unsigned long gp_seq = 0; > > static struct rcu_torture_ops *torture_ops[] = { > > &rcu_ops, &rcu_busted_ops, &srcu_ops, &srcud_ops, &busted_srcud_ops, > > - TASKS_OPS TASKS_RUDE_OPS TASKS_TRACING_OPS > > + TASKS_OPS TASKS_RUDE_OPS TASKS_TRACING_OPS LAZY_OPS > > &trivial_ops, > > }; > > > > diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE11 b/tools/testing/selftests/rcutorture/configs/rcu/TREE11 > > new file mode 100644 > > index 000000000000..436013f3e015 > > --- /dev/null > > +++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE11 > > @@ -0,0 +1,18 @@ > > +CONFIG_SMP=y > > +CONFIG_PREEMPT_NONE=n > > +CONFIG_PREEMPT_VOLUNTARY=n > > +CONFIG_PREEMPT=y > > +#CHECK#CONFIG_PREEMPT_RCU=y > > +CONFIG_HZ_PERIODIC=n > > +CONFIG_NO_HZ_IDLE=y > > +CONFIG_NO_HZ_FULL=n > > +CONFIG_RCU_TRACE=y > > +CONFIG_HOTPLUG_CPU=y > > +CONFIG_MAXSMP=y > > +CONFIG_CPUMASK_OFFSTACK=y > > +CONFIG_RCU_NOCB_CPU=y > > +CONFIG_DEBUG_LOCK_ALLOC=n > > +CONFIG_RCU_BOOST=n > > +CONFIG_DEBUG_OBJECTS_RCU_HEAD=n > > +CONFIG_RCU_EXPERT=y > > +CONFIG_RCU_LAZY=y > > diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE11.boot b/tools/testing/selftests/rcutorture/configs/rcu/TREE11.boot > > new file mode 100644 > > index 000000000000..9b6f720d4ccd > > --- /dev/null > > +++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE11.boot > > @@ -0,0 +1,8 @@ > > +maxcpus=8 nr_cpus=43 > > +rcutree.gp_preinit_delay=3 > > +rcutree.gp_init_delay=3 > > +rcutree.gp_cleanup_delay=3 > > +rcu_nocbs=0-7 > > +rcutorture.torture_type=rcu_lazy > > +rcutorture.nocbs_nthreads=8 > > +rcutorture.fwd_progress=0 > > -- > > 2.37.0.rc0.161.g10f37bed90-goog > >