[PATCH] mm/thp/migration: switch from flush_tlb_range to flush_pmd_tlb_range

[Aneesh Kumar K.V]

We remove one instace of flush_tlb_range here. That was added by
f714f4f20e59ea6eea264a86b9a51fd51b88fc54 ("mm: numa: call MMU notifiers
on THP migration"). But the pmdp_huge_clear_flush_notify should have
done the require flush for us. Hence remove the extra flush.

Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
---
 mm/migrate.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index b1034f9c77e7..c079c115d038 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1767,7 +1767,10 @@ int migrate_misplaced_transhuge_page(struct mm_struct 
*mm,
                put_page(new_page);
                goto out_fail;
        }
-
+       /*
+        * We are not sure a pending tlb flush here is for a huge page
+        * mapping or not. Hence use the tlb range variant
+        */
        if (mm_tlb_flush_pending(mm))
                flush_tlb_range(vma, mmun_start, mmun_end);
 
@@ -1823,12 +1826,11 @@ fail_putback:
        page_add_anon_rmap(new_page, vma, mmun_start, true);
        pmdp_huge_clear_flush_notify(vma, mmun_start, pmd);
        set_pmd_at(mm, mmun_start, pmd, entry);
-       flush_tlb_range(vma, mmun_start, mmun_end);
        update_mmu_cache_pmd(vma, address, &entry);
 
        if (page_count(page) != 2) {
                set_pmd_at(mm, mmun_start, pmd, orig_entry);
-               flush_tlb_range(vma, mmun_start, mmun_end);
+               flush_pmd_tlb_range(vma, mmun_start, mmun_end);
                mmu_notifier_invalidate_range(mm, mmun_start, mmun_end);
                update_mmu_cache_pmd(vma, address, &entry);
                page_remove_rmap(new_page, true);
-- 
2.5.0