[PATCH v8 01/10] mm: mempolicy: add queue_pages_required()

From: Zi Yan
Date: Sat Jul 01 2017 - 09:41:34 EST


From: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>

Introduce a separate check routine related to MPOL_MF_INVERT flag.
This patch just does cleanup, no behavioral change.

Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Signed-off-by: Zi Yan <zi.yan@xxxxxxxxxxxxxx>
---
mm/mempolicy.c | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index d911fa5cb2a7..58166bf1d1fd 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -412,6 +412,21 @@ struct queue_pages {
};

/*
+ * Check if the page's nid is in qp->nmask.
+ *
+ * If MPOL_MF_INVERT is set in qp->flags, check if the nid is
+ * in the invert of qp->nmask.
+ */
+static inline bool queue_pages_required(struct page *page,
+ struct queue_pages *qp)
+{
+ int nid = page_to_nid(page);
+ unsigned long flags = qp->flags;
+
+ return node_isset(nid, *qp->nmask) == !(flags & MPOL_MF_INVERT);
+}
+
+/*
* Scan through pages checking if pages follow certain conditions,
* and move them to the pagelist if they do.
*/
@@ -464,8 +479,7 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr,
*/
if (PageReserved(page))
continue;
- nid = page_to_nid(page);
- if (node_isset(nid, *qp->nmask) == !!(flags & MPOL_MF_INVERT))
+ if (!queue_pages_required(page, qp))
continue;
if (PageTransCompound(page)) {
get_page(page);
@@ -497,7 +511,6 @@ static int queue_pages_hugetlb(pte_t *pte, unsigned long hmask,
#ifdef CONFIG_HUGETLB_PAGE
struct queue_pages *qp = walk->private;
unsigned long flags = qp->flags;
- int nid;
struct page *page;
spinlock_t *ptl;
pte_t entry;
@@ -507,8 +520,7 @@ static int queue_pages_hugetlb(pte_t *pte, unsigned long hmask,
if (!pte_present(entry))
goto unlock;
page = pte_page(entry);
- nid = page_to_nid(page);
- if (node_isset(nid, *qp->nmask) == !!(flags & MPOL_MF_INVERT))
+ if (!queue_pages_required(page, qp))
goto unlock;
/* With MPOL_MF_MOVE, we migrate only unshared hugepage. */
if (flags & (MPOL_MF_MOVE_ALL) ||
--
2.11.0