Re: [BUGFIX][PATCH] oom-kill: fix NUMA consraint check withnodemask v2

From: KAMEZAWA Hiroyuki
Date: Tue Nov 10 2009 - 02:27:37 EST


On Tue, 10 Nov 2009 16:24:22 +0900 (JST)
KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> wrote:

> Hi
>
> > ===================================================================
> > --- mmotm-2.6.32-Nov2.orig/mm/oom_kill.c
> > +++ mmotm-2.6.32-Nov2/mm/oom_kill.c
> > @@ -196,27 +196,40 @@ unsigned long badness(struct task_struct
> > /*
> > * Determine the type of allocation constraint.
> > */
> > +#ifdef CONFIG_NUMA
> > static inline enum oom_constraint constrained_alloc(struct zonelist *zonelist,
> > - gfp_t gfp_mask)
> > + gfp_t gfp_mask, nodemask_t *nodemask)
> > {
> > -#ifdef CONFIG_NUMA
> > struct zone *zone;
> > struct zoneref *z;
> > enum zone_type high_zoneidx = gfp_zone(gfp_mask);
> > - nodemask_t nodes = node_states[N_HIGH_MEMORY];
> > + int ret = CONSTRAINT_NONE;
> >
> > - for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
> > - if (cpuset_zone_allowed_softwall(zone, gfp_mask))
> > - node_clear(zone_to_nid(zone), nodes);
> > - else
> > + /*
> > + * The nodemask here is a nodemask passed to alloc_pages(). Now,
> > + * cpuset doesn't use this nodemask for its hardwall/softwall/hierarchy
> > + * feature. Then, only mempolicy use this nodemask.
> > + */
> > + if (nodemask && nodes_equal(*nodemask, node_states[N_HIGH_MEMORY]))
> > + ret = CONSTRAINT_MEMORY_POLICY;
>
> !nodes_equal() ?
>
yes. will fix.

>
> > +
> > + /* Check this allocation failure is caused by cpuset's wall function */
> > + for_each_zone_zonelist_nodemask(zone, z, zonelist,
> > + high_zoneidx, nodemask)
> > + if (!cpuset_zone_allowed_softwall(zone, gfp_mask))
> > return CONSTRAINT_CPUSET;
>
> If cpuset and MPOL_BIND are both used, Probably CONSTRAINT_MEMORY_POLICY is
> better choice.
>

No. this memory allocation is failed by limitation of cpuset's alloc mask.
Not from mempolicy.


Thanks,
-Kame

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/