Re: [PATCH v2 2/2] mm/compaction: avoid rescanning pageblocks in isolate_freepages

David Rientjes
2014-05-22T02:51:18Z

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On Mon, 19 May 2014, Vlastimil Babka wrote:

> Fix a (spurious) build warning:
>
> mm/compaction.c:860:15: warning: ‘next_free_pfn’ may be used uninitialized in this function [-Wmaybe-uninitialized]
>
> Seems like the compiler cannot prove that exiting the for loop without updating
> next_free_pfn there will mean that the check for crossing the scanners will
> trigger. So let's not confuse people who try to see why this warning occurs.
>
> Instead of initializing next_free_pfn to zero with an explaining comment, just
> drop the damned variable altogether and work with cc->free_pfn directly as
> Nayoa originally suggested.
>

s/Nayoa/Naoya/

> Suggested-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

Acked-by: David Rientjes <rientjes@google.com>