With new refcounting pte entries can point to tail pages. It's doesn't make much sense to mark tail page locked -- we need to protect whole compound page.
This patch adjust helpers related to PG_locked to operate on head page. Signed-off-by: Kirill A. Shutemov <[email protected]> --- include/linux/page-flags.h | 3 ++- include/linux/pagemap.h | 5 +++++ mm/filemap.c | 1 + mm/slub.c | 2 ++ 4 files changed, 10 insertions(+), 1 deletion(-) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 5ed7bdaf22d5..d471370f27e8 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -207,7 +207,8 @@ static inline int __TestClearPage##uname(struct page *page) { return 0; } struct page; /* forward declaration */ -TESTPAGEFLAG(Locked, locked) +#define PageLocked(page) test_bit(PG_locked, &compound_head(page)->flags) + PAGEFLAG(Error, error) TESTCLEARFLAG(Error, error) PAGEFLAG(Referenced, referenced) TESTCLEARFLAG(Referenced, referenced) __SETPAGEFLAG(Referenced, referenced) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 4b3736f7065c..ad6da4e49555 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -428,16 +428,19 @@ extern void unlock_page(struct page *page); static inline void __set_page_locked(struct page *page) { + VM_BUG_ON_PAGE(PageTail(page), page); __set_bit(PG_locked, &page->flags); } static inline void __clear_page_locked(struct page *page) { + VM_BUG_ON_PAGE(PageTail(page), page); __clear_bit(PG_locked, &page->flags); } static inline int trylock_page(struct page *page) { + page = compound_head(page); return (likely(!test_and_set_bit_lock(PG_locked, &page->flags))); } @@ -490,6 +493,7 @@ extern int wait_on_page_bit_killable_timeout(struct page *page, static inline int wait_on_page_locked_killable(struct page *page) { + page = compound_head(page); if (PageLocked(page)) return wait_on_page_bit_killable(page, PG_locked); return 0; @@ -510,6 +514,7 @@ static inline void wake_up_page(struct page *page, int bit) */ static inline void wait_on_page_locked(struct page *page) { + page = compound_head(page); if (PageLocked(page)) wait_on_page_bit(page, PG_locked); } diff --git a/mm/filemap.c b/mm/filemap.c index ad7242043bdb..b02c3f7cbe64 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -744,6 +744,7 @@ EXPORT_SYMBOL_GPL(add_page_wait_queue); */ void unlock_page(struct page *page) { + page = compound_head(page); VM_BUG_ON_PAGE(!PageLocked(page), page); clear_bit_unlock(PG_locked, &page->flags); smp_mb__after_atomic(); diff --git a/mm/slub.c b/mm/slub.c index 0909e13cf708..16ba8c9665e2 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -338,11 +338,13 @@ static inline int oo_objects(struct kmem_cache_order_objects x) */ static __always_inline void slab_lock(struct page *page) { + VM_BUG_ON_PAGE(PageTail(page), page); bit_spin_lock(PG_locked, &page->flags); } static __always_inline void slab_unlock(struct page *page) { + VM_BUG_ON_PAGE(PageTail(page), page); __bit_spin_unlock(PG_locked, &page->flags); } -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
