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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 CF0ECC43331 for ; Thu, 2 Apr 2020 09:15:16 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 98AB82063A for ; Thu, 2 Apr 2020 09:15:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="KQPQsGNt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 98AB82063A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=UlBubqQLtIgsj21bcKcHyQcIsEESLIKUo4bLP/GUVRo=; b=KQPQsGNt6fkPu3 yp2rh7w9iX5z+fGedXMbqXm0lJjQ+zP1dI93AFZjWJ9ftSYmK8TWc7c3wHTjoy4/ho1gt5RoLBwHs s7iw/pp8Q3uAOMBwZB5KJfkjCnQtpWlUZF2+S1ob2GtxUtaCNdSVvxpaNRdo+0yPPCxm7HVB5TESZ 2sFgMC4qfk+w9k+4kWx2JI63u3o4wLlKZo60NJUvb9CT7AuhO1D48Gifo8dEno8how1FTCYyRih9q o03yzmh7l8jsLRWSdF8Igt24TPLwArq/f6ARHrSxPctxSoF704n5ZwKAWN6rqOCU7Z6Iz0DQ4ikWK guBkKDE2z32un9sNuo7w==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jJvwS-0000ar-58; Thu, 02 Apr 2020 09:15:16 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jJvwO-0008En-4C for linux-arm-kernel@lists.infradead.org; Thu, 02 Apr 2020 09:15:13 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7D44831B; Thu, 2 Apr 2020 02:15:08 -0700 (PDT) Received: from bogus (unknown [10.37.12.97]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4DAF93F68F; Thu, 2 Apr 2020 02:15:06 -0700 (PDT) Date: Thu, 2 Apr 2020 10:14:55 +0100 From: Sudeep Holla To: Linus Walleij Subject: Re: [PATCH] cpufreq: Select schedutil when using big.LITTLE Message-ID: <20200402091446.GA19366@bogus> References: <20200402080239.7471-1-linus.walleij@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200402080239.7471-1-linus.walleij@linaro.org> User-Agent: Mutt/1.9.4 (2018-02-28) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200402_021512_214385_A51717F2 X-CRM114-Status: GOOD ( 16.36 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Arnd Bergmann , linux-pm@vger.kernel.org, Viresh Kumar , "Rafael J . Wysocki" , Russell King , Sudeep Holla , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Apr 02, 2020 at 10:02:39AM +0200, Linus Walleij wrote: > When we are using a system with big.LITTLE HMP > configuration, we need to use EAS to schedule the > system. > > As can be seen from kernel/sched/topology.c: > > "EAS can be used on a root domain if it meets all the following conditions: > 1. an Energy Model (EM) is available; > 2. the SD_ASYM_CPUCAPACITY flag is set in the sched_domain hierarchy. > 3. no SMT is detected. > 4. the EM complexity is low enough to keep scheduling overheads low; > 5. schedutil is driving the frequency of all CPUs of the rd;" > > This means that at the very least, schedutil needs to be > available as a scheduling policy for EAS to work on these > systems. Make this explicit by defaulting to the schedutil > governor if BIG_LITTLE is selected. > > Currently users of the TC2 board (like me) has to figure these > dependencies out themselves and it is not helpful. > > Suggested-by: Arnd Bergmann > Cc: Vincent Guittot > Cc: Viresh Kumar > Cc: Sudeep Holla Good to see another user of TC2 ;) FWIW: Acked-by: Sudeep Holla -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel