thp: share get_huge_page_tail()

commit b35a35b556f5e6b7993ad0baf20173e75c09ce8c upstream.

This avoids duplicating the function in every arch gup_fast.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 1c59d94f59422c754cba2fa305e6e01a1c235b37..da5eb388570210ca9aa70ba0de41444659c49d02 100644 (file)
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -385,17 +385,6 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
        return NULL;
 }
 
-static inline void get_huge_page_tail(struct page *page)
-{
-       /*
-        * __split_huge_page_refcount() cannot run
-        * from under us.
-        */
-       VM_BUG_ON(page_mapcount(page) < 0);
-       VM_BUG_ON(atomic_read(&page->_count) != 0);
-       atomic_inc(&page->_mapcount);
-}
-
 static noinline int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
                       unsigned long end, int write, struct page **pages, int *nr)
 {

diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c
index da33a0281d9dbccc3444a2305b6a3ff4bff9d39f..65cb06e2af4eaa0a7b18b2e3b0f5b4b1af8be9d8 100644 (file)
--- a/arch/s390/mm/gup.c
+++ b/arch/s390/mm/gup.c
@@ -48,17 +48,6 @@ static inline int gup_pte_range(pmd_t *pmdp, pmd_t pmd, unsigned long addr,
        return 1;
 }
 
-static inline void get_huge_page_tail(struct page *page)
-{
-       /*
-        * __split_huge_page_refcount() cannot run
-        * from under us.
-        */
-       VM_BUG_ON(page_mapcount(page) < 0);
-       VM_BUG_ON(atomic_read(&page->_count) != 0);
-       atomic_inc(&page->_mapcount);
-}
-
 static inline int gup_huge_pmd(pmd_t *pmdp, pmd_t pmd, unsigned long addr,
                unsigned long end, int write, struct page **pages, int *nr)
 {

diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c
index 3b5032a62b0f3e41c98b98c0842500215e9e3e18..ea305856151cefc62fccd7f216519bc9d5f2945c 100644 (file)
--- a/arch/x86/mm/gup.c
+++ b/arch/x86/mm/gup.c
@@ -108,17 +108,6 @@ static inline void get_head_page_multiple(struct page *page, int nr)
        SetPageReferenced(page);
 }
 
-static inline void get_huge_page_tail(struct page *page)
-{
-       /*
-        * __split_huge_page_refcount() cannot run
-        * from under us.
-        */
-       VM_BUG_ON(page_mapcount(page) < 0);
-       VM_BUG_ON(atomic_read(&page->_count) != 0);
-       atomic_inc(&page->_mapcount);
-}
-
 static noinline int gup_huge_pmd(pmd_t pmd, unsigned long addr,
                unsigned long end, int write, struct page **pages, int *nr)
 {

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 26fd168c670ad0e8297a67f4017bc4570cb1e367..18eea056b47dcc6c174c13c0460ae9cf051da484 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -375,6 +375,17 @@ static inline int page_count(struct page *page)
        return atomic_read(&compound_head(page)->_count);
 }
 
+static inline void get_huge_page_tail(struct page *page)
+{
+       /*
+        * __split_huge_page_refcount() cannot run
+        * from under us.
+        */
+       VM_BUG_ON(page_mapcount(page) < 0);
+       VM_BUG_ON(atomic_read(&page->_count) != 0);
+       atomic_inc(&page->_mapcount);
+}
+
 extern bool __get_page_tail(struct page *page);
 
 static inline void get_page(struct page *page)