From mboxrd@z Thu Jan 1 00:00:00 1970 From: "SungEun Kim(cleaneye.kim@lge.com)" Subject: Re: Re: [PATCH v2] PM / Sleep: Use workqueue for user space wakeup sources garbage collector Date: Fri, 3 Jul 2015 14:03:05 +0900 Message-ID: <55961789.5090709@lge.com> References: <1435718938-19088-1-git-send-email-cleaneye.kim@lge.com> <1435739328-17021-1-git-send-email-cleaneye.kim@lge.com> <1544571.4tSqBEqESU@vostro.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1544571.4tSqBEqESU@vostro.rjw.lan> Sender: linux-kernel-owner@vger.kernel.org To: "Rafael J. Wysocki" Cc: pavel@ucw.cz, len.brown@intel.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-pm@vger.kernel.org On 2015-07-03 =EC=98=A4=EC=A0=84 9:15, Rafael J. Wysocki wrote: > On Wednesday, July 01, 2015 05:28:48 PM SungEun Kim wrote: >> From: "SungEun Kim" >> >> The synchronous synchronize_rcu in wakeup_source_remove makes user > process >> which writes to /sys/kernel/wake_unlock blocked sometimes. >> >> For example, when android eventhub tries to release wakelock, >> this blocking process can occur, and eventhub can't get input event >> for a while. >> >> Using workqueue instead of direct function call at pm_wake_unlock >> can prevent this unnecessary delay of an user space process. >=20 > The idea is defendable, but the patch is too simple. >=20 > For example, if the garbage collection is in progress, it is not usef= ul > to start a new one. >=20 > Also the incrementation and clearing of wakelocks_gc_count should be = under > the lock. Thank you for your advices. I will correct and amend my patch and then submit v3 patch. Thank you. SungEun Kim >=20 >=20 > --=20 > I speak only for myself. > Rafael J. Wysocki, Intel Open Source Technology Center.