The patch titled
Subject: thp: introduce hugepage_get_pmd()
has been added to the -mm tree. Its filename is
thp-introduce-hugepage_get_pmd.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Bob Liu <lliubbo@xxxxxxxxx>
Subject: thp: introduce hugepage_get_pmd()
Introduce hugepage_get_pmd() to simple code.
Signed-off-by: Bob Liu <lliubbo@xxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxx>
Cc: Minchan Kim <minchan.kim@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/huge_memory.c | 68 +++++++++++++++++----------------------------
1 file changed, 27 insertions(+), 41 deletions(-)
diff -puN mm/huge_memory.c~thp-introduce-hugepage_get_pmd mm/huge_memory.c
--- a/mm/huge_memory.c~thp-introduce-hugepage_get_pmd
+++ a/mm/huge_memory.c
@@ -1185,6 +1185,25 @@ int change_huge_pmd(struct vm_area_struc
return ret;
}
+static pmd_t *hugepage_get_pmd(struct mm_struct *mm, unsigned long address)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd = NULL;
+
+ pgd = pgd_offset(mm, address);
+ if (!pgd_present(*pgd))
+ goto out;
+
+ pud = pud_offset(pgd, address);
+ if (!pud_present(*pud))
+ goto out;
+
+ pmd = pmd_offset(pud, address);
+out:
+ return pmd;
+}
+
/*
* Returns 1 if a given pmd maps a stable (not under splitting) thp.
* Returns -1 if it maps a thp under splitting. Returns 0 otherwise.
@@ -1215,22 +1234,14 @@ pmd_t *page_check_address_pmd(struct pag
unsigned long address,
enum page_check_address_pmd_flag flag)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd, *ret = NULL;
if (address & ~HPAGE_PMD_MASK)
goto out;
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- goto out;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
+ pmd = hugepage_get_pmd(mm, address);
+ if (!pmd)
goto out;
-
- pmd = pmd_offset(pud, address);
if (pmd_none(*pmd))
goto out;
if (pmd_page(*pmd) != page)
@@ -1975,8 +1986,6 @@ static void collapse_huge_page(struct mm
struct vm_area_struct *vma,
int node)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd, _pmd;
pte_t *pte;
pgtable_t pgtable;
@@ -2022,16 +2031,9 @@ static void collapse_huge_page(struct mm
goto out;
VM_BUG_ON(vma->vm_flags & VM_NO_THP);
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- goto out;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
+ pmd = hugepage_get_pmd(mm, address);
+ if (!pmd)
goto out;
-
- pmd = pmd_offset(pud, address);
- /* pmd can't go away or become huge under us */
if (!pmd_present(*pmd) || pmd_trans_huge(*pmd))
goto out;
@@ -2115,8 +2117,6 @@ static int khugepaged_scan_pmd(struct mm
unsigned long address,
struct page **hpage)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd;
pte_t *pte, *_pte;
int ret = 0, referenced = 0, none = 0;
@@ -2127,15 +2127,9 @@ static int khugepaged_scan_pmd(struct mm
VM_BUG_ON(address & ~HPAGE_PMD_MASK);
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- goto out;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
+ pmd = hugepage_get_pmd(mm, address);
+ if (!pmd)
goto out;
-
- pmd = pmd_offset(pud, address);
if (!pmd_present(*pmd) || pmd_trans_huge(*pmd))
goto out;
@@ -2428,21 +2422,13 @@ void __split_huge_page_pmd(struct mm_str
static void split_huge_page_address(struct mm_struct *mm,
unsigned long address)
{
- pgd_t *pgd;
- pud_t *pud;
pmd_t *pmd;
VM_BUG_ON(!(address & ~HPAGE_PMD_MASK));
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- return;
-
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
+ pmd = hugepage_get_pmd(mm, address);
+ if (!pmd)
return;
-
- pmd = pmd_offset(pud, address);
if (!pmd_present(*pmd))
return;
/*
_
Patches currently in -mm which might be from lliubbo@xxxxxxxxx are
linux-next.patch
thp-clean-up-__collapse_huge_page_isolate.patch
thp-introduce-hugepage_get_pmd.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
