migrate: add hugepage migration code to migrate_pages()
Extend check_range() to handle vma with VM_HUGETLB set. We will be able
to migrate hugepage with migrate_pages(2) after applying the enablement
patch which comes later in this series.
Note that for larger hugepages (covered by pud entries, 1GB for x86_64 for
example), we simply skip it now.
Note that using pmd_huge/pud_huge assumes that hugepages are pointed to by
pmd/pud. This is not true in some architectures implementing hugepage
with other mechanisms like ia64, but it's OK because pmd_huge/pud_huge
simply return 0 in such arch and page walker simply ignores such
hugepages.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Acked-by: Hillf Danton <dhillf@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 27022ca..4626be6 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -515,6 +515,30 @@
return addr != end;
}
+static void check_hugetlb_pmd_range(struct vm_area_struct *vma, pmd_t *pmd,
+ const nodemask_t *nodes, unsigned long flags,
+ void *private)
+{
+#ifdef CONFIG_HUGETLB_PAGE
+ int nid;
+ struct page *page;
+
+ spin_lock(&vma->vm_mm->page_table_lock);
+ page = pte_page(huge_ptep_get((pte_t *)pmd));
+ nid = page_to_nid(page);
+ if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT))
+ goto unlock;
+ /* With MPOL_MF_MOVE, we migrate only unshared hugepage. */
+ if (flags & (MPOL_MF_MOVE_ALL) ||
+ (flags & MPOL_MF_MOVE && page_mapcount(page) == 1))
+ isolate_huge_page(page, private);
+unlock:
+ spin_unlock(&vma->vm_mm->page_table_lock);
+#else
+ BUG();
+#endif
+}
+
static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud,
unsigned long addr, unsigned long end,
const nodemask_t *nodes, unsigned long flags,
@@ -526,6 +550,13 @@
pmd = pmd_offset(pud, addr);
do {
next = pmd_addr_end(addr, end);
+ if (!pmd_present(*pmd))
+ continue;
+ if (pmd_huge(*pmd) && is_vm_hugetlb_page(vma)) {
+ check_hugetlb_pmd_range(vma, pmd, nodes,
+ flags, private);
+ continue;
+ }
split_huge_page_pmd(vma, addr, pmd);
if (pmd_none_or_trans_huge_or_clear_bad(pmd))
continue;
@@ -547,6 +578,8 @@
pud = pud_offset(pgd, addr);
do {
next = pud_addr_end(addr, end);
+ if (pud_huge(*pud) && is_vm_hugetlb_page(vma))
+ continue;
if (pud_none_or_clear_bad(pud))
continue;
if (check_pmd_range(vma, pud, addr, next, nodes,
@@ -638,9 +671,6 @@
return ERR_PTR(-EFAULT);
}
- if (is_vm_hugetlb_page(vma))
- goto next;
-
if (flags & MPOL_MF_LAZY) {
change_prot_numa(vma, start, endvma);
goto next;
@@ -993,7 +1023,11 @@
static struct page *new_node_page(struct page *page, unsigned long node, int **x)
{
- return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE, 0);
+ if (PageHuge(page))
+ return alloc_huge_page_node(page_hstate(compound_head(page)),
+ node);
+ else
+ return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE, 0);
}
/*
@@ -1023,7 +1057,7 @@
err = migrate_pages(&pagelist, new_node_page, dest,
MIGRATE_SYNC, MR_SYSCALL);
if (err)
- putback_lru_pages(&pagelist);
+ putback_movable_pages(&pagelist);
}
return err;