diff options
author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2016-01-15 16:51:17 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-15 17:56:32 -0800 |
commit | 0e6d31a7336f41ef0375f5398c79e54de8e219b6 (patch) | |
tree | eb716f43a4a5d24413b8fae8fc73e73760177200 /include | |
parent | d8c1bdeb5d6b62b34a78391206a5e55e4a02d58f (diff) |
page-flags: move code around
The preparation patch: we are going to use compound_head(), PageTail()
and PageCompound() to define page-flags helpers.
Let's define them before macros.
We cannot user PageHead() helper in PageCompound() as it's not yet
defined -- use test_bit(PG_head, &page->flags) instead.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
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: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/page-flags.h | 41 |
1 files changed, 21 insertions, 20 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 45792d01edea..83161a22509c 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -133,6 +133,27 @@ enum pageflags { #ifndef __GENERATING_BOUNDS_H +struct page; /* forward declaration */ + +static inline struct page *compound_head(struct page *page) +{ + unsigned long head = READ_ONCE(page->compound_head); + + if (unlikely(head & 1)) + return (struct page *) (head - 1); + return page; +} + +static inline int PageTail(struct page *page) +{ + return READ_ONCE(page->compound_head) & 1; +} + +static inline int PageCompound(struct page *page) +{ + return test_bit(PG_head, &page->flags) || PageTail(page); +} + /* * Macros to create function definitions for page flags */ @@ -204,7 +225,6 @@ static inline int __TestClearPage##uname(struct page *page) { return 0; } #define TESTSCFLAG_FALSE(uname) \ TESTSETFLAG_FALSE(uname) TESTCLEARFLAG_FALSE(uname) -struct page; /* forward declaration */ TESTPAGEFLAG(Locked, locked) PAGEFLAG(Error, error) TESTCLEARFLAG(Error, error) @@ -395,11 +415,6 @@ static inline void set_page_writeback_keepwrite(struct page *page) __PAGEFLAG(Head, head) CLEARPAGEFLAG(Head, head) -static inline int PageTail(struct page *page) -{ - return READ_ONCE(page->compound_head) & 1; -} - static inline void set_compound_head(struct page *page, struct page *head) { WRITE_ONCE(page->compound_head, (unsigned long)head + 1); @@ -410,20 +425,6 @@ static inline void clear_compound_head(struct page *page) WRITE_ONCE(page->compound_head, 0); } -static inline struct page *compound_head(struct page *page) -{ - unsigned long head = READ_ONCE(page->compound_head); - - if (unlikely(head & 1)) - return (struct page *) (head - 1); - return page; -} - -static inline int PageCompound(struct page *page) -{ - return PageHead(page) || PageTail(page); - -} #ifdef CONFIG_TRANSPARENT_HUGEPAGE static inline void ClearPageCompound(struct page *page) { |