thp: rename split_huge_page_pmd() to split_huge_pmd()

We are going to decouple splitting THP PMD from splitting underlying
compound page.

This patch renames split_huge_page_pmd*() functions to split_huge_pmd*()
to reflect the fact that it doesn't imply page splitting, only PMD.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 11 insertions, 21 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index f4da89cef2cd..0d70ec056ecc 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1233,13 +1233,13 @@ alloc:
 
 	if (unlikely(!new_page)) {
 		if (!page) {
-			split_huge_page_pmd(vma, address, pmd);
+			split_huge_pmd(vma, pmd, address);
 			ret |= VM_FAULT_FALLBACK;
 		} else {
 			ret = do_huge_pmd_wp_page_fallback(mm, vma, address,
 					pmd, orig_pmd, page, haddr);
 			if (ret & VM_FAULT_OOM) {
-				split_huge_page(page);
+				split_huge_pmd(vma, pmd, address);
 				ret |= VM_FAULT_FALLBACK;
 			}
 			put_user_huge_page(page);
@@ -1252,10 +1252,10 @@ alloc:
 					   true))) {
 		put_page(new_page);
 		if (page) {
-			split_huge_page(page);
+			split_huge_pmd(vma, pmd, address);
 			put_user_huge_page(page);
 		} else
-			split_huge_page_pmd(vma, address, pmd);
+			split_huge_pmd(vma, pmd, address);
 		ret |= VM_FAULT_FALLBACK;
 		count_vm_event(THP_FAULT_FALLBACK);
 		goto out;
@@ -3131,17 +3131,7 @@ again:
 		goto again;
 }
 
-void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,
-		pmd_t *pmd)
-{
-	struct vm_area_struct *vma;
-
-	vma = find_vma(mm, address);
-	BUG_ON(vma == NULL);
-	split_huge_page_pmd(vma, address, pmd);
-}
-
-static void split_huge_page_address(struct mm_struct *mm,
+static void split_huge_pmd_address(struct vm_area_struct *vma,
 				    unsigned long address)
 {
 	pgd_t *pgd;
@@ -3150,7 +3140,7 @@ static void split_huge_page_address(struct mm_struct *mm,
 
 	VM_BUG_ON(!(address & ~HPAGE_PMD_MASK));
 
-	pgd = pgd_offset(mm, address);
+	pgd = pgd_offset(vma->vm_mm, address);
 	if (!pgd_present(*pgd))
 		return;
 
@@ -3159,13 +3149,13 @@ static void split_huge_page_address(struct mm_struct *mm,
 		return;
 
 	pmd = pmd_offset(pud, address);
-	if (!pmd_present(*pmd))
+	if (!pmd_present(*pmd) || !pmd_trans_huge(*pmd))
 		return;
 	/*
 	 * Caller holds the mmap_sem write mode, so a huge pmd cannot
 	 * materialize from under us.
 	 */
-	split_huge_page_pmd_mm(mm, address, pmd);
+	__split_huge_page_pmd(vma, address, pmd);
 }
 
 void vma_adjust_trans_huge(struct vm_area_struct *vma,
@@ -3181,7 +3171,7 @@ void vma_adjust_trans_huge(struct vm_area_struct *vma,
 	if (start & ~HPAGE_PMD_MASK &&
 	    (start & HPAGE_PMD_MASK) >= vma->vm_start &&
 	    (start & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE <= vma->vm_end)
-		split_huge_page_address(vma->vm_mm, start);
+		split_huge_pmd_address(vma, start);
 
 	/*
 	 * If the new end address isn't hpage aligned and it could
@@ -3191,7 +3181,7 @@ void vma_adjust_trans_huge(struct vm_area_struct *vma,
 	if (end & ~HPAGE_PMD_MASK &&
 	    (end & HPAGE_PMD_MASK) >= vma->vm_start &&
 	    (end & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE <= vma->vm_end)
-		split_huge_page_address(vma->vm_mm, end);
+		split_huge_pmd_address(vma, end);
 
 	/*
 	 * If we're also updating the vma->vm_next->vm_start, if the new
@@ -3205,6 +3195,6 @@ void vma_adjust_trans_huge(struct vm_area_struct *vma,
 		if (nstart & ~HPAGE_PMD_MASK &&
 		    (nstart & HPAGE_PMD_MASK) >= next->vm_start &&
 		    (nstart & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE <= next->vm_end)
-			split_huge_page_address(next->vm_mm, nstart);
+			split_huge_pmd_address(next, nstart);
 	}
 }