On 07/29/2014 11:39 PM, Christoph Lameter wrote: > On Tue, 29 Jul 2014, Tejun Heo wrote: > >> Hmmm, well, then it's something else. Either a bug in workqueue or in >> the caller. Given the track record, the latter is more likely. >> e.g. it looks kinda suspicious that the work func is cleared after >> cancel_delayed_work_sync() is called. What happens if somebody tries >> to schedule it inbetween? > > Here is yet another patch to also address this idea: > > Subject: vmstat: Clear the work.func before cancelling delayed work > > Looks strange to me but Tejun thinks this could do some good. > If this really is the right thing to do then cancel_delayed_work should > zap the work func itselt I think. > > Signed-off-by: Christoph Lameter <cl@xxxxxxxxx> > > > Index: linux/mm/vmstat.c > =================================================================== > --- linux.orig/mm/vmstat.c 2014-07-29 10:22:45.073884943 -0500 > +++ linux/mm/vmstat.c 2014-07-29 10:34:45.083369228 -0500 > @@ -1277,8 +1277,8 @@ static int vmstat_cpuup_callback(struct > break; > case CPU_DOWN_PREPARE: > case CPU_DOWN_PREPARE_FROZEN: > - cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu)); > per_cpu(vmstat_work, cpu).work.func = NULL; > + cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu)); I think we should just remove "per_cpu(vmstat_work, cpu).work.func = NULL;" > break; > case CPU_DOWN_FAILED: > case CPU_DOWN_FAILED_FROZEN: > . > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>