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 DD22DC38A2D for ; Mon, 24 Oct 2022 12:32:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233985AbiJXMcn (ORCPT ); Mon, 24 Oct 2022 08:32:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233983AbiJXM3I (ORCPT ); Mon, 24 Oct 2022 08:29:08 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77CF387FB0; Mon, 24 Oct 2022 05:03:06 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6E680612DA; Mon, 24 Oct 2022 11:54:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 83682C433D6; Mon, 24 Oct 2022 11:54:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666612467; bh=jUlYH+CCO+C1GozJgPk99oAfl+QuIg9M6++iiseMq9I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IuO43QW+vapaFCju19mj4ZC+60gSwnyTJz7u9Ep5bG0FGwcecTTUwt+Sbm3KurU8c FRdC6Kz/AYc/IBLplKIdWwiqkUH1EWG57NnWedCOywFWeR3RIdT7rBN7F6iBqpmDiB YD+XDzQK0wR0NJj7WYJHoaNj8Vv0+zC41wDd1C9U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Rafael J. Wysocki" , Chen Yu Subject: [PATCH 4.14 210/210] thermal: intel_powerclamp: Use first online CPU as control_cpu Date: Mon, 24 Oct 2022 13:32:07 +0200 Message-Id: <20221024113003.827869862@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024112956.797777597@linuxfoundation.org> References: <20221024112956.797777597@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki commit 4bb7f6c2781e46fc5bd00475a66df2ea30ef330d upstream. Commit 68b99e94a4a2 ("thermal: intel_powerclamp: Use get_cpu() instead of smp_processor_id() to avoid crash") fixed an issue related to using smp_processor_id() in preemptible context by replacing it with a pair of get_cpu()/put_cpu(), but what is needed there really is any online CPU and not necessarily the one currently running the code. Arguably, getting the one that's running the code in there is confusing. For this reason, simply give the control CPU role to the first online one which automatically will be CPU0 if it is online, so one check can be dropped from the code for an added benefit. Link: https://lore.kernel.org/linux-pm/20221011113646.GA12080@duo.ucw.cz/ Fixes: 68b99e94a4a2 ("thermal: intel_powerclamp: Use get_cpu() instead of smp_processor_id() to avoid crash") Signed-off-by: Rafael J. Wysocki Reviewed-by: Chen Yu Signed-off-by: Greg Kroah-Hartman --- drivers/thermal/intel_powerclamp.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) --- a/drivers/thermal/intel_powerclamp.c +++ b/drivers/thermal/intel_powerclamp.c @@ -549,11 +549,7 @@ static int start_power_clamp(void) get_online_cpus(); /* prefer BSP */ - control_cpu = 0; - if (!cpu_online(control_cpu)) { - control_cpu = get_cpu(); - put_cpu(); - } + control_cpu = cpumask_first(cpu_online_mask); clamping = true; schedule_delayed_work(&poll_pkg_cstate_work, 0);