From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [PATCH 1/4] freezer: make fake_signal_wake_up wake TASK_KILLABLE tasks too Date: Tue, 11 Oct 2011 21:14:28 +0200 Message-ID: <201110112114.28478.rjw@sisk.pl> References: <1317210761-11518-1-git-send-email-jlayton@redhat.com> <20111011061847.GB1377@ucw.cz> <20111011061000.3a3a03fe@tlielax.poochiereds.net> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: Pavel Machek , trond.myklebust-HgOvQuBEEgTQT0dZR+AlfA@public.gmane.org, smfrench-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-pm-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, john-HpsXz0BELY4AvxtiuMwx3w@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jeff Layton Return-path: In-Reply-To: <20111011061000.3a3a03fe-9yPaYZwiELC+kQycOl6kW4xkIHaj4LzF@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-cifs.vger.kernel.org On Tuesday, October 11, 2011, Jeff Layton wrote: > On Tue, 11 Oct 2011 08:18:48 +0200 > Pavel Machek wrote: > > > > > Hi! > > > > > TASK_KILLABLE is often used to put tasks to sleep for quite some time. > > > One of the most common uses is to put tasks to sleep while waiting for > > > replies from a server on a networked filesystem (such as CIFS or NFS). > > > > > > Unfortunately, fake_signal_wake_up does not currently wake up tasks > > > that are sleeping in TASK_KILLABLE state. This means that even if the > > > code were in place to allow them to freeze while in this sleep, it > > > wouldn't work anyway. > > > > > > This patch changes this function to wake tasks in this state as well. > > > This should be harmless -- if the code doing the sleeping doesn't have > > > handling to deal with freezer events, it should just go back to sleep. > > > > I'm pretty sure this will break something; but that does not mean it > > is bad idea, just that it should be merged early and tested a lot. > > > > FWIW, I looked at most of the places in the kernel that do > TASK_KILLABLE sleeps and they look like they'll handle this correctly. > The main one I wasn't sure about was mem_cgroup_handle_oom(), but I > think it'll do the right thing too. I certainly could have missed > something though... > > In any case, would you mind merging this via the linux-pm tree for 3.2? I will push it for 3.2. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html