diff options
author | Andrea Arcangeli <aarcange@redhat.com> | 2011-11-02 13:37:31 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-11-02 16:06:58 -0700 |
commit | e0d85a366c2300efd230ef82a9b22110b0658331 (patch) | |
tree | 4965cd894ac64947afc7fbb7f5a0303c99e76b28 | |
parent | 0693bc9ce2cc4f6a1b9c3c05790fc149a74c0b87 (diff) |
sparc: gup_pte_range() support THP based tail recounting
Up to this point the code assumed old refcounting for hugepages (pre-thp).
This updates the code directly to the thp mapcount tail page refcounting.
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>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | arch/sparc/mm/gup.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c index a986b5d0571..afcebac144f 100644 --- a/arch/sparc/mm/gup.c +++ b/arch/sparc/mm/gup.c @@ -12,6 +12,17 @@ #include <linux/rwsem.h> #include <asm/pgtable.h> +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); +} + /* * The performance critical leaf functions are made noinline otherwise gcc * inlines everything into a single function which results in too much @@ -56,6 +67,8 @@ static noinline int gup_pte_range(pmd_t pmd, unsigned long addr, put_page(head); return 0; } + if (head != page) + get_huge_page_tail(page); pages[*nr] = page; (*nr)++; |