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=-8.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C8C1DC433DF for ; Thu, 14 May 2020 14:20:30 +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 96A1B2070A for ; Thu, 14 May 2020 14:20:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="K8BqOvgq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 96A1B2070A 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=jnet2OiS2O0Byq+uRVGJys7GaM3fjMnNFmOnqPlDo6g=; b=K8BqOvgqAVvs5y KhOrZ2fMQFqyzSu+yr37dBLehCuA9urObvQ9nDL4hJ41MS6NYPgjLRQX7c2utAQk544nMTC125CPj N1bbRcJ2VqZjV1VOWpzuhcQ9xss+ESsvSoYQ2aX9LMQbllTe6Um8vp6B76bhwEFK7rislApKK0TkN pLbzcb680KDqMYxw+fpK1wkGbgA5iY/leqQ+zO3SamxLwvyLC55/dkODPty7U9fYJ7T17UJjtBPSn XtRk2uDmeQGjDSfryOR/QQMZvObwwlfYgiPT851meJhECATEZO6F+gt3gur/3jn2gBLuND8t2QtC+ 1nIyAV9k7PSC+Q7j1pKQ==; 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 1jZEis-0006zV-2W; Thu, 14 May 2020 14:20:30 +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 1jZEio-0006yB-AN for linux-arm-kernel@lists.infradead.org; Thu, 14 May 2020 14:20:27 +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 38AB51045; Thu, 14 May 2020 07:20:23 -0700 (PDT) Received: from bogus (unknown [10.37.8.154]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D7DAE3F71E; Thu, 14 May 2020 07:20:20 -0700 (PDT) Date: Thu, 14 May 2020 15:20:15 +0100 From: Sudeep Holla To: Ulf Hansson Subject: Re: [PATCH] cpuidle: psci: Fixup execution order when entering a domain idle state Message-ID: <20200514142015.GA23401@bogus> References: <20200511133346.21706-1-ulf.hansson@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200511133346.21706-1-ulf.hansson@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-20200514_072026_400022_4005AD6B X-CRM114-Status: GOOD ( 16.67 ) 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: Lorenzo Pieralisi , Benjamin Gaignard , linux-pm@vger.kernel.org, Stephen Boyd , Daniel Lezcano , "Rafael J . Wysocki" , Lina Iyer , Bjorn Andersson , 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 Mon, May 11, 2020 at 03:33:46PM +0200, Ulf Hansson wrote: > Moving forward, platforms are going to need to execute specific "last-man" > operations before a domain idle state can be entered. I need to dig the thread details, but I remember commenting on one of the similar discussion. It was something to do with voting which wasn't necessary at all. I am interested in the details here. > In one way or the other, these operations needs to be triggered while > walking the hierarchical topology via runtime PM and genpd, as it's at that > point the last-man becomes known. > > Moreover, executing last-man operations needs to be done after the CPU PM > notifications are sent through cpu_pm_enter(), as otherwise it's likely > that some notifications would fail. Therefore, let's re-order the sequence > in psci_enter_domain_idle_state(), so cpu_pm_enter() gets called prior > pm_runtime_put_sync(). > More details on why notifications fail ? > Fixes: ce85aef570df ("cpuidle: psci: Manage runtime PM in the idle path") > Reported-by: Lina Iyer > Signed-off-by: Ulf Hansson > --- > drivers/cpuidle/cpuidle-psci.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/cpuidle/cpuidle-psci.c b/drivers/cpuidle/cpuidle-psci.c > index bae9140a65a5..d0fb585073c6 100644 > --- a/drivers/cpuidle/cpuidle-psci.c > +++ b/drivers/cpuidle/cpuidle-psci.c > @@ -58,6 +58,10 @@ static int psci_enter_domain_idle_state(struct cpuidle_device *dev, > u32 state; > int ret; > > + ret = cpu_pm_enter(); > + if (ret) > + return -1; > + This change is ignoring the retention case psci_enter_state handles and this may affect performance by doing unnecessary save/restore. -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel