Revert "mm: sched: numa: Delay PTE scanning until a task is scheduled on a new node"
authorMel Gorman <mgorman@suse.de>
Mon, 7 Oct 2013 10:28:53 +0000 (11:28 +0100)
committerIngo Molnar <mingo@kernel.org>
Wed, 9 Oct 2013 10:40:17 +0000 (12:40 +0200)
commitb726b7dfb400c937546fa91cf8523dcb1aa2fc6e
treeb4a6f741b630bb22568536860f3f46e94c4e8904
parent9e645ab6d089f5822479a833c6977c785bcfffe3
Revert "mm: sched: numa: Delay PTE scanning until a task is scheduled on a new node"

PTE scanning and NUMA hinting fault handling is expensive so commit
5bca2303 ("mm: sched: numa: Delay PTE scanning until a task is scheduled
on a new node") deferred the PTE scan until a task had been scheduled on
another node. The problem is that in the purely shared memory case that
this may never happen and no NUMA hinting fault information will be
captured. We are not ruling out the possibility that something better
can be done here but for now, this patch needs to be reverted and depend
entirely on the scan_delay to avoid punishing short-lived processes.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-16-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
include/linux/mm_types.h
kernel/fork.c
kernel/sched/fair.c
kernel/sched/features.h