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 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 873A9C55189 for ; Wed, 22 Apr 2020 11:29:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6023320784 for ; Wed, 22 Apr 2020 11:29:37 +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="AJZNSrzE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726703AbgDVL30 (ORCPT ); Wed, 22 Apr 2020 07:29:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45764 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725808AbgDVL3Z (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 1B025C03C1A8 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=IPsokMf7j12ulQ4L+xCcKx1w5TI7LQr2p0tSldOtxhc=; b=AJZNSrzEp21IlLS+Xdfk4y2mqA bTO57Z7UlLKDG6wcJxOsF+iVpd6iQYhvLlFghKDMjD9hBoaDPeLsApdqn0Sicc1Z61M7wAKt1chBz mfMg622CjzWcxixF5nKsbAzia6HAdc+UvHoYjegIHTgJWFGhn1wiF/4BnFsa3INNgdtHcYN5hdKQQ Mo6fQfZDjrUC9hMP7wsovnp6Rln4NIN1oV79fBk/rqH0XYDayuTOhlRUw2fzHW7o30LCAlVpWhxJ5 U0NClOAyEv71XNb6UwFXQhaask6Jiiy+nGm3bu52c2IuanxIWjolMUYhRLf/FuualNr0Ydrcj1aY4 ElhnaO5A==; 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 1jRDYv-0003aV-4S; Wed, 22 Apr 2020 11:29:05 +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 3205D30788D; Wed, 22 Apr 2020 13:29:03 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id C835A200C9C87; Wed, 22 Apr 2020 13:29:02 +0200 (CEST) Message-Id: <20200422112831.574539982@infradead.org> User-Agent: quilt/0.65 Date: Wed, 22 Apr 2020 13:27:25 +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, daniel.lezcano@linaro.org, sudeep.holla@arm.com Subject: [PATCH 06/23] sched,psci: 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. XXX this thing is horrific, it basically open-codes a stop-machine and idle. Cc: daniel.lezcano@linaro.org Cc: sudeep.holla@arm.com Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Ingo Molnar --- drivers/firmware/psci/psci_checker.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) --- a/drivers/firmware/psci/psci_checker.c +++ b/drivers/firmware/psci/psci_checker.c @@ -272,7 +272,6 @@ static int suspend_test_thread(void *arg { int cpu = (long)arg; int i, nb_suspend = 0, nb_shallow_sleep = 0, nb_err = 0; - struct sched_param sched_priority = { .sched_priority = MAX_RT_PRIO-1 }; struct cpuidle_device *dev; struct cpuidle_driver *drv; /* No need for an actual callback, we just want to wake up the CPU. */ @@ -282,9 +281,8 @@ static int suspend_test_thread(void *arg wait_for_completion(&suspend_threads_started); /* Set maximum priority to preempt all other threads on this CPU. */ - if (sched_setscheduler_nocheck(current, SCHED_FIFO, &sched_priority)) - pr_warn("Failed to set suspend thread scheduler on CPU %d\n", - cpu); + if (sched_set_fifo(current)) + pr_warn("Failed to set suspend thread scheduler on CPU %d\n", cpu); dev = this_cpu_read(cpuidle_devices); drv = cpuidle_get_cpu_driver(dev); @@ -349,11 +347,6 @@ static int suspend_test_thread(void *arg if (atomic_dec_return_relaxed(&nb_active_threads) == 0) complete(&suspend_threads_done); - /* Give up on RT scheduling and wait for termination. */ - sched_priority.sched_priority = 0; - if (sched_setscheduler_nocheck(current, SCHED_NORMAL, &sched_priority)) - pr_warn("Failed to set suspend thread scheduler on CPU %d\n", - cpu); for (;;) { /* Needs to be set first to avoid missing a wakeup. */ set_current_state(TASK_INTERRUPTIBLE);