From e39155ea11eac6da056b04669d7c9fc612e2065a Mon Sep 17 00:00:00 2001 From: Kirill A. Shutemov Date: Wed, 15 Apr 2015 16:14:53 -0700 Subject: mm: uninline and cleanup page-mapping related helpers Most-used page->mapping helper -- page_mapping() -- has already uninlined. Let's uninline also page_rmapping() and page_anon_vma(). It saves us depending on configuration around 400 bytes in text: text data bss dec hex filename 660318 99254 410000 1169572 11d8a4 mm/built-in.o-before 659854 99254 410000 1169108 11d6d4 mm/built-in.o I also tried to make code a bit more clean. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Kirill A. Shutemov Cc: Christoph Lameter Cc: Konstantin Khlebnikov Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/util.c | 41 ++++++++++++++++++++++++++++++++++++----- 1 file changed, 36 insertions(+), 5 deletions(-) (limited to 'mm/util.c') diff --git a/mm/util.c b/mm/util.c index 3981ae9d1b15..68ff8a5361e7 100644 --- a/mm/util.c +++ b/mm/util.c @@ -325,9 +325,37 @@ void kvfree(const void *addr) } EXPORT_SYMBOL(kvfree); +static inline void *__page_rmapping(struct page *page) +{ + unsigned long mapping; + + mapping = (unsigned long)page->mapping; + mapping &= ~PAGE_MAPPING_FLAGS; + + return (void *)mapping; +} + +/* Neutral page->mapping pointer to address_space or anon_vma or other */ +void *page_rmapping(struct page *page) +{ + page = compound_head(page); + return __page_rmapping(page); +} + +struct anon_vma *page_anon_vma(struct page *page) +{ + unsigned long mapping; + + page = compound_head(page); + mapping = (unsigned long)page->mapping; + if ((mapping & PAGE_MAPPING_FLAGS) != PAGE_MAPPING_ANON) + return NULL; + return __page_rmapping(page); +} + struct address_space *page_mapping(struct page *page) { - struct address_space *mapping = page->mapping; + unsigned long mapping; /* This happens if someone calls flush_dcache_page on slab page */ if (unlikely(PageSlab(page))) @@ -337,10 +365,13 @@ struct address_space *page_mapping(struct page *page) swp_entry_t entry; entry.val = page_private(page); - mapping = swap_address_space(entry); - } else if ((unsigned long)mapping & PAGE_MAPPING_ANON) - mapping = NULL; - return mapping; + return swap_address_space(entry); + } + + mapping = (unsigned long)page->mapping; + if (mapping & PAGE_MAPPING_FLAGS) + return NULL; + return page->mapping; } int overcommit_ratio_handler(struct ctl_table *table, int write, -- cgit v1.2.3-55-g7522