On Tue 17-12-24 19:07:15, alexei.starovoitov@xxxxxxxxx wrote: > From: Alexei Starovoitov <ast@xxxxxxxxxx> > > Introduce free_pages_nolock() that can free pages without taking locks. > It relies on trylock and can be called from any context. > Since spin_trylock() cannot be used in RT from hard IRQ or NMI > it uses lockless link list to stash the pages which will be freed > by subsequent free_pages() from good context. Yes, this makes sense. Have you tried a simpler implementation that would just queue on the lockless link list unconditionally? That would certainly reduce the complexity. Essentially something similar that we do in vfree_atomic (well, except the queue_work which is likely too heavy for the usecase and potentialy not reentrant). -- Michal Hocko SUSE Labs
