On Thu, 6 Feb 2014 11:41:36 -0500 Johannes Weiner <han...@cmpxchg.org> wrote:
> > Make the shadow lru->node[i].lock IRQ-safe to remove the order > dictated by interruption. This slightly increases the IRQ-disabled > section in the shadow shrinker, but it still drops all locks and > enables IRQ after every reclaimed shadow radix tree node. > > ... > > --- a/mm/workingset.c > +++ b/mm/workingset.c > @@ -273,7 +273,10 @@ static unsigned long count_shadow_nodes(struct shrinker > *shrinker, > unsigned long max_nodes; > unsigned long pages; > > + local_irq_disable(); > shadow_nodes = list_lru_count_node(&workingset_shadow_nodes, sc->nid); > + local_irq_enable(); This is a bit ugly-looking. A reader will look at that and wonder why the heck we're disabling interrupts here. Against what? Is there some way in which we can clarify this? Perhaps adding list_lru_count_node_irq[save] and list_lru_walk_node_irq[save] would be better - is it reasonable to assume this is the only caller of the list_lru code which will ever want irq-safe treatment? This is all somewhat a side-effect of list_lru implementing its own locking rather than requiring caller-provided locking. It's always a mistake. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
