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=-3.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 25A9CC55189 for ; Wed, 22 Apr 2020 11:30:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F2E3920784 for ; Wed, 22 Apr 2020 11:30:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OfkSuJ9n" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728211AbgDVLaj (ORCPT ); Wed, 22 Apr 2020 07:30:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45770 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726448AbgDVL3Z (ORCPT ); Wed, 22 Apr 2020 07:29:25 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 228D9C03C1AB for ; Wed, 22 Apr 2020 04:29:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-Id:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=llWoNTl7a6WItJGcLBTC8j7ePN5aoj4IZ6+7VC2n6DI=; b=OfkSuJ9norfNio6+xaZkqCPpmL uNvQeSVJwV5Oekx6j971guWZ8znLdsuxfPzj8d/G6v9sjYot0CoKmY5mgCPKovW/DaU2bsjb8VbS+ h0NAlhdvBWEA5SDk79bbtEBTlg05I38pZCnmblEg67hikwX+mZt//ogXYs0+UXuDGBcRS38oNMWoZ p0bZotU0LRp31LYLnI58R3VrSaZrf1rr4+2IEkc0fqgKROgNJDYM/rZ0Ij9MOKdTGhxT240nAmSlQ YVUFRTA32gMMw2dy+vH9DQMq1yfIeW5728QgDY3Mgl9oPp/ApK/MXWZ5IvkzdqfNeUJhtXdPT0fpS fbq8R3Dw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jRDYy-0003bO-KM; Wed, 22 Apr 2020 11:29:08 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 5719D30797F; Wed, 22 Apr 2020 13:29:03 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 07F5C22B99F04; Wed, 22 Apr 2020 13:29:03 +0200 (CEST) Message-Id: <20200422112832.283981577@infradead.org> User-Agent: quilt/0.65 Date: Wed, 22 Apr 2020 13:27:37 +0200 From: Peter Zijlstra To: mingo@kernel.org, linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, rostedt@goodmis.org, qais.yousef@arm.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, peterz@infradead.org, paulmck@kernel.org Subject: [PATCH 18/23] sched,locktorture: Convert to sched_set_fifo() References: <20200422112719.826676174@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Because SCHED_FIFO is a broken scheduler model (see previous patches) take away the priority field, the kernel can't possibly make an informed decision. Effectively changes prio from 99 to 50. Cc: paulmck@kernel.org Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Ingo Molnar --- kernel/locking/locktorture.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -436,8 +436,6 @@ static int torture_rtmutex_lock(void) __ static void torture_rtmutex_boost(struct torture_random_state *trsp) { - int policy; - struct sched_param param; const unsigned int factor = 50000; /* yes, quite arbitrary */ if (!rt_task(current)) { @@ -448,8 +446,7 @@ static void torture_rtmutex_boost(struct */ if (trsp && !(torture_random(trsp) % (cxt.nrealwriters_stress * factor))) { - policy = SCHED_FIFO; - param.sched_priority = MAX_RT_PRIO - 1; + sched_set_fifo(current); } else /* common case, do nothing */ return; } else { @@ -462,13 +459,10 @@ static void torture_rtmutex_boost(struct */ if (!trsp || !(torture_random(trsp) % (cxt.nrealwriters_stress * factor * 2))) { - policy = SCHED_NORMAL; - param.sched_priority = 0; + sched_set_normal(current, 0); } else /* common case, do nothing */ return; } - - sched_setscheduler_nocheck(current, policy, ¶m); } static void torture_rtmutex_delay(struct torture_random_state *trsp)