sched/numa: Add infrastructure for split shared/private accounting of NUMA hinting faults

Ideally it would be possible to distinguish between NUMA hinting faults
that are private to a task and those that are shared.  This patch prepares
infrastructure for separately accounting shared and private faults by
allocating the necessary buffers and passing in relevant information. For
now, all faults are treated as private and detection will be introduced
later.

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/1381141781-10992-26-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 8677dbf31c2e..914216733e0a 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1282,7 +1282,7 @@ int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
         struct page *page;
         unsigned long haddr = addr & HPAGE_PMD_MASK;
         int page_nid = -1, this_nid = numa_node_id();
-        int target_nid;
+        int target_nid, last_nid = -1;
         bool page_locked;
         bool migrated = false;
 
@@ -1293,6 +1293,7 @@ int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
         page = pmd_page(pmd);
         BUG_ON(is_huge_zero_page(page));
         page_nid = page_to_nid(page);
+        last_nid = page_nid_last(page);
         count_vm_numa_event(NUMA_HINT_FAULTS);
         if (page_nid == this_nid)
                 count_vm_numa_event(NUMA_HINT_FAULTS_LOCAL);
@@ -1361,7 +1362,7 @@ out:
                 page_unlock_anon_vma_read(anon_vma);
 
         if (page_nid != -1)
-                task_numa_fault(page_nid, HPAGE_PMD_NR, migrated);
+                task_numa_fault(last_nid, page_nid, HPAGE_PMD_NR, migrated);
 
         return 0;
 }