mm: vmscan: when kswapd is awoken due to reclaim by a running task - by dorimanx from anarkia1976/AK-xGenesis

Set the priority of kswapd to that of the calling task thus making memory reclaim cpu activity affected by nice level.

http://ck.kolivas.org/patches/3.0/3.9/3.9-ck1/patches/mm-kswapd_inherit_prio-1.patch

https://github.com/anarkia1976/AK-xGenesis/commit/04304466f1bed4ddcbd257b3c40b0e1accb5de47#diff-e688914da9c733fb09af712240dc95afR2933