Hello, Sorry about the delay. On Thu, Aug 31, 2017 at 07:33:42AM +0200, Michal Hocko wrote: > > > Michal, are you sure that this patch does not cause deadlock? > > > > > > As shown in "[PATCH] mm: Use WQ_HIGHPRI for mm_percpu_wq." thread, > > > currently work > > > items on mm_percpu_wq seem to be blocked by other work items not on > > > mm_percpu_wq.
IIUC that wasn't a deadlock but more a legitimate starvation from too many tasks trying to reclaim directly. > > But we have a rescuer so we should make a forward progress eventually. > > Or am I missing something. Tejun, could you have a look please? > > ping... I would really appreaciate if you could double check my thinking > Tejun. This is a tricky area and I would like to prevent further subtle > issues here. So, this shouldn't be an issue. This may get affected by direct reclaim frenzy but it's only a small piece of the whole symptom and we gotta fix that at the source. Thanks. -- tejun
