On Fri, 17 Jul 2009, Peter Zijlstra wrote: > On Fri, 2009-07-17 at 12:25 +0000, Thomas Gleixner wrote: > > plain text document attachment (freezer-fix-accounting-for-real.patch) > > commit e3c8ca8336 (sched: do not count frozen tasks toward load) broke > > the nr_uninterruptible accounting on freeze/thaw. On freeze the task > > is excluded from accounting with a check for (task->flags & > > PF_FROZEN), but that flag is cleared before the task is thawed. So > > while we prevent that the freezing task with state > > TASK_UNINTERRUPTIBLE is accounted to nr_uninterruptible we decrement > > nr_uninterruptible on thaw. > > > > Use a separate flag which is handled by the freezing task itself. Set > > it before calling the scheduler with TASK_UNINTERRUPTIBLE state and > > clear it after we return from frozen state. > > Right, so I'm wondering why we don't fully revert e3c8ca8336 to begin > with. Fine with me, but it seems that the cgroup folks have some luser space stuff looking at proc/loadavg which goes berserk when loadavg increases rapidly due to freezing. OTOH that stuff seems to be oblivious to the fact that the commit in question brings loadavg irreversibly to 0 when you do enough freeze/thaw cycles. So either we revert or apply the fix, which keeps the accounting straight and solves the freezer loadavg thing. No strong opinion on that. Thanks, tglx _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
