Messages in this thread | | | Date | Thu, 26 Jul 2018 09:44:30 +0200 | From | Michal Hocko <> | Subject | Re: Re: [PATCH] [PATCH] mm: disable preemption before swapcache_free |
| |
On Thu 26-07-18 15:03:23, zhaowuyun@wingtech.com wrote: > >On Thu 26-07-18 10:21:40, zhaowuyun@wingtech.com wrote: > >[...] > >> Our project really needs a fix to this issue > > > >Could you be more specific why? My understanding is that RT tasks > >usually have all the memory mlocked otherwise all the real time > >expectations are gone already. > >-- > >Michal Hocko > >SUSE Labs > > > The RT thread is created by a process with normal priority, and the process was sleep, > then some task needs the RT thread to do something, so the process create this thread, and set it to RT policy. > I think that is the reason why RT task would read the swap.
OK I see. This design is quite fragile though. You are opening ticket to priority inversions and what not.
Anyway, the underlying swap issue should be fixed. Unfortunatelly I do not have a great idea how to do that properly.
-- Michal Hocko SUSE Labs
| |