Re: [PATCH] mm/compaction: reset compaction scanner positions

From: Gioh Kim
Date: Mon Mar 23 2015 - 21:24:55 EST




2015-03-24 ìì 8:16ì David Rientjes ì(ê) ì ê:
On Sat, 21 Mar 2015, Gioh Kim wrote:

When the compaction is activated via /proc/sys/vm/compact_memory
it would better scan the whole zone.
And some platform, for instance ARM, has the start_pfn of a zone is zero.
Therefore the first try to compaction via /proc doesn't work.
It needs to force to reset compaction scanner position at first.

Signed-off-by: Gioh Kim <gioh.kim@xxxxx>

That shouldn't be a valid email address.

It's my fault. I'm going to send patch again.


Acked-by: Vlastimil Babka <vbabka@xxxxxxx>

Acked-by: David Rientjes <rientjes@xxxxxxxxxx>

I was thinking that maybe this would be better handled as part of the
comapct_zone() logic, i.e. set cc->free_pfn and cc->migrate_pfn based on a
helper function that understands cc->order == -1 should compact the entire
zone. However, after scanning the entire zone as a result of this write,
the existing cached pfns probably don't matter anymore. So this seems
fine.

--
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/