From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukas Wunner Subject: Re: [PATCH v3 0/8] PM / ACPI / i2c: Deploy runtime PM centric path for system sleep Date: Mon, 4 Sep 2017 07:46:37 +0200 Message-ID: <20170904054637.GA23707@wunner.de> References: <1504018610-10822-1-git-send-email-ulf.hansson@linaro.org> <3033151.kbPpEQGlRq@aspire.rjw.lan> <1668277.7DWLdgHGid@aspire.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mailout2.hostsharing.net ([83.223.90.233]:45169 "EHLO mailout2.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750782AbdIDFqk (ORCPT ); Mon, 4 Sep 2017 01:46:40 -0400 Content-Disposition: inline In-Reply-To: <1668277.7DWLdgHGid@aspire.rjw.lan> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" Cc: Ulf Hansson , Wolfram Sang , Len Brown , ACPI Devel Maling List , "linux-pm@vger.kernel.org" , Kevin Hilman , Jarkko Nikula , Andy Shevchenko , Mika Westerberg , Jisheng Zhang , John Stultz , Guodong Xu , Sumit Semwal , Haojian Zhuang , Johannes Stezenbach , "linux-arm-kernel@lists.infradead.org" , "linux-i2c@vger.kernel.org" On Mon, Sep 04, 2017 at 02:17:21AM +0200, Rafael J. Wysocki wrote: > OTOH I'm starting to think that direct_complete is only theoretically > useful and may not be actually set very often in practice, whereas it > adds significant complexity to the code, so I'm not sure about it any > more. That makes me come out of the woodwork as a direct_complete fan: Runtime resuming a discrete GPU on a modern dual GPU laptop takes about 1.5 sec, runtime resuming Thunderbolt controllers more than 2 sec. A discrete GPU easily consumes 10W, a Thunderbolt controller 2W. So not having direct_complete would noticeably delay system suspend and resume as well as reduce battery life. Lukas From mboxrd@z Thu Jan 1 00:00:00 1970 From: lukas@wunner.de (Lukas Wunner) Date: Mon, 4 Sep 2017 07:46:37 +0200 Subject: [PATCH v3 0/8] PM / ACPI / i2c: Deploy runtime PM centric path for system sleep In-Reply-To: <1668277.7DWLdgHGid@aspire.rjw.lan> References: <1504018610-10822-1-git-send-email-ulf.hansson@linaro.org> <3033151.kbPpEQGlRq@aspire.rjw.lan> <1668277.7DWLdgHGid@aspire.rjw.lan> Message-ID: <20170904054637.GA23707@wunner.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Sep 04, 2017 at 02:17:21AM +0200, Rafael J. Wysocki wrote: > OTOH I'm starting to think that direct_complete is only theoretically > useful and may not be actually set very often in practice, whereas it > adds significant complexity to the code, so I'm not sure about it any > more. That makes me come out of the woodwork as a direct_complete fan: Runtime resuming a discrete GPU on a modern dual GPU laptop takes about 1.5 sec, runtime resuming Thunderbolt controllers more than 2 sec. A discrete GPU easily consumes 10W, a Thunderbolt controller 2W. So not having direct_complete would noticeably delay system suspend and resume as well as reduce battery life. Lukas