--- a/include/linux/page_ref.h~mm-introduce-page_ref_sub_return +++ a/include/linux/page_ref.h @@ -102,6 +102,15 @@ static inline void page_ref_sub(struct p __page_ref_mod(page, -nr); } +static inline int page_ref_sub_return(struct page *page, int nr) +{ + int ret = atomic_sub_return(nr, &page->_refcount); + + if (page_ref_tracepoint_active(__tracepoint_page_ref_mod_and_return)) + __page_ref_mod_and_return(page, -nr, ret); + return ret; +} + static inline void page_ref_inc(struct page *page) { atomic_inc(&page->_refcount);