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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 6C8CBC433E2 for ; Tue, 23 Jun 2020 00:32:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A2B52053B for ; Tue, 23 Jun 2020 00:32:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592872329; bh=l+pOIyYggzjNshzyGc05k+ujOGvhTY4fPpmjwkalyqs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=LnPf1aXzbYo1PXO9El2dnLnJ7CH2+o8yVkIsPYsfakcUX/8mq3dNUiJNGhdVSUSaM UNTGFd0TMufVX7pGYkQkMdzuYObZiK1IAhFzUNYTvwfMJtmapAwOxCnKExWSAVtVVP ngaH/CH/epBMBErUqWAkqKrgVnhSxHLv4ODX3vy0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731960AbgFWAcI (ORCPT ); Mon, 22 Jun 2020 20:32:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:55292 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731644AbgFWAaR (ORCPT ); Mon, 22 Jun 2020 20:30:17 -0400 Received: from paulmck-ThinkPad-P72.home (50-39-105-78.bvtn.or.frontiernet.net [50.39.105.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C2AA2206C1; Tue, 23 Jun 2020 00:30:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592872216; bh=l+pOIyYggzjNshzyGc05k+ujOGvhTY4fPpmjwkalyqs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rBJ6yCi0QfxxSLnIADn12EBnaLr+xW+an+S8mk61BbEsLlli4tchro3iv75eQWVYP g2h7k0g4V2AyJGIQvKx1uuOAARSpS/HhEX4iouzglgYPB683fBkHgrqVzv117JLP1f yCfBnoS2lhx9qXTiQcY2yuqqBSln6/0OWv8nKtIU= 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, dipankar@in.ibm.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 08/30] refperf: Convert nreaders to a module parameter Date: Mon, 22 Jun 2020 17:29:51 -0700 Message-Id: <20200623003013.26252-8-paulmck@kernel.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20200623002941.GA26089@paulmck-ThinkPad-P72> References: <20200623002941.GA26089@paulmck-ThinkPad-P72> Sender: rcu-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org From: "Paul E. McKenney" This commit converts nreaders to a module parameter, with the default of -1 specifying the old behavior of using 75% of the readers. Cc: Joel Fernandes (Google) Signed-off-by: Paul E. McKenney --- kernel/rcu/refperf.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/kernel/rcu/refperf.c b/kernel/rcu/refperf.c index e991d48..020e55a 100644 --- a/kernel/rcu/refperf.c +++ b/kernel/rcu/refperf.c @@ -62,6 +62,12 @@ torture_param(int, holdoff, IS_BUILTIN(CONFIG_RCU_REF_PERF_TEST) ? 10 : 0, "Holdoff time before test start (s)"); // Number of loops per experiment, all readers execute operations concurrently. torture_param(long, loops, 10000000, "Number of loops per experiment."); +// Number of readers, with -1 defaulting to about 75% of the CPUs. +torture_param(int, nreaders, -1, "Number of readers, -1 for 75% of CPUs."); +// Number of runs. +torture_param(int, nruns, 30, "Number of experiments to run."); +// Reader delay in nanoseconds, 0 for no delay. +torture_param(int, readdelay, 0, "Read-side delay in nanoseconds."); #ifdef MODULE # define REFPERF_SHUTDOWN 0 @@ -93,7 +99,6 @@ static wait_queue_head_t main_wq; static int shutdown_start; static struct reader_task *reader_tasks; -static int nreaders; // Number of readers that are part of the current experiment. static atomic_t nreaders_exp; @@ -411,8 +416,8 @@ static void ref_perf_print_module_parms(struct ref_perf_ops *cur_ops, const char *tag) { pr_alert("%s" PERF_FLAG - "--- %s: verbose=%d shutdown=%d holdoff=%d loops=%ld\n", perf_type, tag, - verbose, shutdown, holdoff, loops); + "--- %s: verbose=%d shutdown=%d holdoff=%d loops=%ld nreaders=%d\n", perf_type, tag, + verbose, shutdown, holdoff, loops, nreaders); } static void @@ -501,8 +506,9 @@ ref_perf_init(void) schedule_timeout_uninterruptible(1); } - // Reader tasks (~75% of online CPUs). - nreaders = (num_online_cpus() >> 1) + (num_online_cpus() >> 2); + // Reader tasks (default to ~75% of online CPUs). + if (nreaders < 0) + nreaders = (num_online_cpus() >> 1) + (num_online_cpus() >> 2); reader_tasks = kcalloc(nreaders, sizeof(reader_tasks[0]), GFP_KERNEL); if (!reader_tasks) { -- 2.9.5