Hello Rafael, > -----Original Message----- > From: Rafael J. Wysocki [mailto:r...@rjwysocki.net] > Sent: Monday, February 17, 2014 7:41 AM > To: Liu, Chuansheng > Cc: gre...@linuxfoundation.org; pa...@ucw.cz; Brown, Len; > linux...@vger.kernel.org; linux-kernel@vger.kernel.org; Li, Zhuangzhi > Subject: Re: [PATCH 0/5] Enabling the asynchronous threads for other phases > > On Monday, February 10, 2014 08:36:57 AM Liu, Chuansheng wrote: > > Hello Rafael, > > > > > -----Original Message----- > > > From: Rafael J. Wysocki [mailto:r...@rjwysocki.net] > > > Sent: Thursday, February 06, 2014 5:53 AM > > > To: Liu, Chuansheng > > > Cc: gre...@linuxfoundation.org; pa...@ucw.cz; Brown, Len; > > > linux...@vger.kernel.org; linux-kernel@vger.kernel.org; Li, Zhuangzhi > > > Subject: Re: [PATCH 0/5] Enabling the asynchronous threads for other > phases > > > > > > On Monday, January 20, 2014 04:44:34 PM Liu, Chuansheng wrote: > > > > Hello, > > > > > > > > This patch series are for enabling the asynchronous threads for the > phases > > > > resume_noirq, resume_early, suspend_noirq and suspend_late. > > > > > > > > Just like commit 5af84b82701a and 97df8c12995, with async threads it > will > > > > reduce the system suspending and resuming time significantly. > > > > > > > > With these patches, in my test platform, it saved 80% time in > resume_noirq > > > > phase. > > > > > > > > Has done the suspend-resume stress test for a long time, please help to > > > > review. > > > > > > > > Best Regards, > > > > > > > > [PATCH 1/5] PM: Adding two flags for async suspend_noirq and > > > > [PATCH 2/5] PM: Enabling the asynchronous threads for resume_noirq > > > > [PATCH 3/5] PM: Enabling the asyncronous threads for resume_early > > > > [PATCH 4/5] PM: Enabling the asyncronous threads for suspend_noirq > > > > [PATCH 5/5] PM: Enabling the asyncronous threads for suspend_late > > > > > > I've applied this to the bleeding-edge branch of the linux-pm.git tree, > > > with > > > minor changes related to coding style, white space etc. > > Thanks your help. > > Unfortunately, I've just realized that your patches don't add any mechanism > ensuring that parent devices' .suspend_noirq() will be called *after* the > .suspend_noirq() of all their children. Of course, analogously for > .suspend_late() and for the resume part (where children have to wait for > their parents). > > In the original async suspend/resume code that is implemented using > power.completion and I suppose you can do the same thing here.
I think "parent devices suspend after their children" is not related directly with using async or not; In the original code, even without asyncing, the suspend/resume has the waiting action, but there no waiting action for suspend_noirq and other phases. If you think the parent waiting for children is necessary for suspend_noirq/suspend_late /resume_early/resume_noirq, I can cook other series patches. But we can separate them with current asyncing series patches. Agree?
