[PATCH] unpaged: unifdefed PageCompound

It looks like snd_xxx is not the only nopage to be using PageReserved as a way
of holding a high-order page together: which no longer works, but is masked by
our failure to free from VM_RESERVED areas.  We cannot fix that bug without
first substituting another way to hold the high-order page together, while
farming out the 0-order pages from within it.

That's just what PageCompound is designed for, but it's been kept under
CONFIG_HUGETLB_PAGE.  Remove the #ifdefs: which saves some space (out- of-line
put_page), doesn't slow down what most needs to be fast (already using
hugetlb), and unifies the way we handle high-order pages.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 0 insertions, 23 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0986d19..9701210 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -311,8 +311,6 @@ struct page {
 
 extern void FASTCALL(__page_cache_release(struct page *));
 
-#ifdef CONFIG_HUGETLB_PAGE
-
 static inline int page_count(struct page *page)
 {
 	if (PageCompound(page))
@@ -329,23 +327,6 @@ static inline void get_page(struct page *page)
 
 void put_page(struct page *page);
 
-#else		/* CONFIG_HUGETLB_PAGE */
-
-#define page_count(p)		(atomic_read(&(p)->_count) + 1)
-
-static inline void get_page(struct page *page)
-{
-	atomic_inc(&page->_count);
-}
-
-static inline void put_page(struct page *page)
-{
-	if (put_page_testzero(page))
-		__page_cache_release(page);
-}
-
-#endif		/* CONFIG_HUGETLB_PAGE */
-
 /*
  * Multiple processes may "see" the same page. E.g. for untouched
  * mappings of /dev/null, all processes see the same page full of
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index f34767c..343083fe 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -287,11 +287,7 @@ extern void __mod_page_state(unsigned long offset, unsigned long delta);
 #define ClearPageReclaim(page)	clear_bit(PG_reclaim, &(page)->flags)
 #define TestClearPageReclaim(page) test_and_clear_bit(PG_reclaim, &(page)->flags)
 
-#ifdef CONFIG_HUGETLB_PAGE
 #define PageCompound(page)	test_bit(PG_compound, &(page)->flags)
-#else
-#define PageCompound(page)	0
-#endif
 #define SetPageCompound(page)	set_bit(PG_compound, &(page)->flags)
 #define ClearPageCompound(page)	clear_bit(PG_compound, &(page)->flags)