mm: kswapd: reset kswapd_max_order and classzone_idx after reading
authorMel Gorman <mel@csn.ul.ie>
Thu, 13 Jan 2011 23:46:23 +0000 (15:46 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 14 Jan 2011 01:32:37 +0000 (17:32 -0800)
commit4d40502ea580c35414a1466d86f96484910ebaec
treeed03d2b5a100be1c3371d304421af221fa893129
parent0abdee2bd4118366c62349a304f81537be69af33
mm: kswapd: reset kswapd_max_order and classzone_idx after reading

When kswapd wakes up, it reads its order and classzone from pgdat and
calls balance_pgdat.  While its awake, it potentially reclaimes at a high
order and a low classzone index.  This might have been a once-off that was
not required by subsequent callers.  However, because the pgdat values
were not reset, they remain artifically high while balance_pgdat() is
running and potentially kswapd enters a second unnecessary reclaim cycle.
Reset the pgdat order and classzone index after reading.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Eric B Munson <emunson@mgebm.net>
Cc: Simon Kirby <sim@hostway.ca>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/vmscan.c