Commit 18e6959c authored Jan 14, 2009 by Nick Piggin Committed by Linus Torvalds Jan 14, 2009

mm: fix assertion

This assertion is incorrect for lockless pagecache. By definition if we
have an unpinned page that we are trying to take a speculative reference
to, it may become the tail of a compound page at any time (if it is
freed, then reallocated as a compound page).

It was still a valid assertion for the vmscan.c LRU isolation case, but
it doesn't seem incredibly helpful... if somebody wants it, they can
put it back directly where it applies in the vmscan code.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent a6525042

include/linux/mm.h

+0 −1

Original line number	Diff line number	Diff line
		@@ -260,7 +260,6 @@ static inline int put_page_testzero(struct page *page)
		*/
		static inline int get_page_unless_zero(struct page *page)
		{
		VM_BUG_ON(PageTail(page));
		return atomic_inc_not_zero(&page->_count);
		}

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