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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 24F32C47082 for ; Tue, 8 Jun 2021 13:56:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0592F61287 for ; Tue, 8 Jun 2021 13:56:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233073AbhFHN5z (ORCPT ); Tue, 8 Jun 2021 09:57:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52116 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233108AbhFHN5y (ORCPT ); Tue, 8 Jun 2021 09:57:54 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9D74C061574 for ; Tue, 8 Jun 2021 06:56:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=apmLwlJ9ogAts22oUWOIOb1nko2tN7etIfj6kyALqpE=; b=d1UYeQIsGbRUhFidHlmOu6LWOZ 5hCaR7KLOY7iu+A3MlWTGoIGvIGJL6s763Y9022zOrG/qPZ3Mim5S6niqHIsCMTjV4HdLzPwoDMnw zs3E/T6TGdOykVuf98MT5UTMbkaBrVlJExLy6L4rlY5DXZMnyvldPO4MjVaL5RsND2xF0bplG4Wym sGcng7YEGBjiB1oUkllniJPcQrjo5oWgZat7jBVUAxRy7etPVmbUIguuZp9Ui9mq2wxJRAfGNuPm2 xzNRDroMWa/I0Xna1N5roUS5Osmmjh1rPaGxdrW79wES7LMHBDQOjfETyT+AtxzJHH6/xeDZ6CLfJ ss/IP45w==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1lqcCv-004lgK-4U; Tue, 08 Jun 2021 13:56:00 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 91CC530018A; Tue, 8 Jun 2021 15:55:59 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 82F12201E7ED1; Tue, 8 Jun 2021 15:55:59 +0200 (CEST) Date: Tue, 8 Jun 2021 15:55:59 +0200 From: Peter Zijlstra To: Frederic Weisbecker Cc: Ingo Molnar , LKML Subject: Re: [PATCH 1/2] sched: Add default dynamic preempt mode Kconfig Message-ID: References: <20210608120442.93587-1-frederic@kernel.org> <20210608120442.93587-2-frederic@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210608120442.93587-2-frederic@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 08, 2021 at 02:04:41PM +0200, Frederic Weisbecker wrote: > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 9e9a5be35cde..df47a8275c37 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -6238,6 +6238,14 @@ enum { > > int preempt_dynamic_mode = preempt_dynamic_full; > > +#if defined(CONFIG_PREEMPT_DYNAMIC_FULL) > +static __initdata int preempt_dynamic_mode_init = preempt_dynamic_full; > +#elif defined(CONFIG_PREEMPT_DYNAMIC_VOLUNTARY) > +static __initdata int preempt_dynamic_mode_init = preempt_dynamic_voluntary; > +#elif defined(CONFIG_PREEMPT_DYNAMIC_NONE) > +static __initdata int preempt_dynamic_mode_init = preempt_dynamic_none; > +#endif Why does preempt_dynamic_mode_init exist? Why can't we simply set preempt_dynamic_mode?