Messages in this thread | | | From | Nick Piggin <> | Subject | Re: [PATCH 7/13] Drain per-cpu lists when high-order allocations fail | Date | Tue, 11 Sep 2007 01:05:25 +1000 |
| |
On Monday 10 September 2007 21:22, Mel Gorman wrote: > Per-cpu pages can accidentally cause fragmentation because they are free, > but pinned pages in an otherwise contiguous block. When this patch is > applied, the per-cpu caches are drained after the direct-reclaim is entered > if the requested order is greater than 0. It simply reuses the code used > by suspend and hotplug.
Does this help? I have a more general version which could go in instead (independently of the anti fragmentation patches).
> Signed-off-by: Mel Gorman <mel@csn.ul.ie> > Signed-off-by: Andrew Morton <akpm@linux-foundation.org> > --- > > mm/page_alloc.c | 24 +++++++++++++++++++++++- > 1 file changed, 23 insertions(+), 1 deletion(-) > > diff -rup -X /usr/src/patchset-0.6/bin//dontdiff > linux-2.6.23-rc5-006-group-short-lived-and-reclaimable-kernel-allocations/m >m/page_alloc.c > linux-2.6.23-rc5-007-drain-per-cpu-lists-when-high-order-allocations-fail/m >m/page_alloc.c --- > linux-2.6.23-rc5-006-group-short-lived-and-reclaimable-kernel-allocations/m >m/page_alloc.c 2007-09-02 16:20:31.000000000 +0100 +++ > linux-2.6.23-rc5-007-drain-per-cpu-lists-when-high-order-allocations-fail/m >m/page_alloc.c 2007-09-02 16:20:48.000000000 +0100 @@ -852,6 +852,7 @@ void > mark_free_pages(struct zone *zone) > } > spin_unlock_irqrestore(&zone->lock, flags); > } > +#endif /* CONFIG_PM */ > > /* > * Spill all of this CPU's per-cpu pages back into the buddy allocator. > @@ -864,7 +865,25 @@ void drain_local_pages(void) > __drain_pages(smp_processor_id()); > local_irq_restore(flags); > } > -#endif /* CONFIG_HIBERNATION */ > + > +void smp_drain_local_pages(void *arg) > +{ > + drain_local_pages(); > +} > + > +/* > + * Spill all the per-cpu pages from all CPUs back into the buddy allocator > + */ > +void drain_all_local_pages(void) > +{ > + unsigned long flags; > + > + local_irq_save(flags); > + __drain_pages(smp_processor_id()); > + local_irq_restore(flags); > + > + smp_call_function(smp_drain_local_pages, NULL, 0, 1); > +} > > /* > * Free a 0-order page > @@ -1452,6 +1471,9 @@ nofail_alloc: > > cond_resched(); > > + if (order != 0) > + drain_all_local_pages(); > + > if (likely(did_some_progress)) { > page = get_page_from_freelist(gfp_mask, order, > zonelist, alloc_flags); > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |