From mboxrd@z Thu Jan 1 00:00:00 1970 From: Felipe Contreras Subject: Re: [linux-pm] suspend blockers & Android integration Date: Mon, 7 Jun 2010 13:25:53 +0300 Message-ID: References: <20100606133130.GA8513@srcf.ucam.org> <20100606152946.GA11351@srcf.ucam.org> <20100606164326.GA12570@srcf.ucam.org> <20100606173146.GA13432@srcf.ucam.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <20100606173146.GA13432@srcf.ucam.org> Sender: linux-kernel-owner@vger.kernel.org To: Matthew Garrett Cc: Vitaly Wool , Brian Swetland , =?UTF-8?B?QXJ2ZSBIasO4bm5ldsOlZw==?= , Arjan van de Ven , tytso@mit.edu, Florian Mickler , Peter Zijlstra , "H. Peter Anvin" , LKML , Neil Brown , James Bottomley , Alan Cox , Linux PM , Ingo Molnar , Linux OMAP Mailing List , Linus Torvalds , Thomas Gleixner , Felipe Balbi List-Id: linux-omap@vger.kernel.org 2010/6/6 Matthew Garrett : > On Sun, Jun 06, 2010 at 07:21:49PM +0200, Vitaly Wool wrote: >> 2010/6/6 Matthew Garrett : >> >> > Suspend blocks prevent system suspend, not any per-device suspend. >> >> Can you suspend a device which is holding a wake lock? > > Yes. Suspend blocks are orthogonal to runtime PM. In that sense yes, but as it has been stated before; if Android user-space concentrates on getting suspend blockers right, then the timers in user-space will not be aligned correctly, and runtime PM wouldn't work that great. Moreover, opportunistic suspend takes the device out of idle. So, as runtime PM gets better, there's a point where opportunistic suspend makes the situation worst. So they are _mostly_ orthogonal, but not completely, at least for the analysis of suspend blockers' usefulness. -- Felipe Contreras