From 224abf92b2f439a9030f21d2926ec8047d1ffcdb Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 6 Jan 2006 00:11:11 -0800 Subject: [PATCH] [PATCH] mm: bad_page optimisation Cut down size slightly by not passing bad_page the function name (it should be able to be determined by dump_stack()). And cut down the number of printks in bad_page. Also, cut down some branching in the destroy_compound_page path. Signed-off-by: Nick Piggin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 42 +++++++++++++++++++----------------------- 1 file changed, 19 insertions(+), 23 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e12154d9c4ed..b9fd2c238f13 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -132,16 +132,16 @@ static inline int bad_range(struct zone *zone, struct page *page) } #endif -static void bad_page(const char *function, struct page *page) +static void bad_page(struct page *page) { - printk(KERN_EMERG "Bad page state at %s (in process '%s', page %p)\n", - function, current->comm, page); - printk(KERN_EMERG "flags:0x%0*lx mapping:%p mapcount:%d count:%d\n", - (int)(2*sizeof(unsigned long)), (unsigned long)page->flags, - page->mapping, page_mapcount(page), page_count(page)); - printk(KERN_EMERG "Backtrace:\n"); + printk(KERN_EMERG "Bad page state in process '%s'\n" + "page:%p flags:0x%0*lx mapping:%p mapcount:%d count:%d\n" + "Trying to fix it up, but a reboot is needed\n" + "Backtrace:\n", + current->comm, page, (int)(2*sizeof(unsigned long)), + (unsigned long)page->flags, page->mapping, + page_mapcount(page), page_count(page)); dump_stack(); - printk(KERN_EMERG "Trying to fix it up, but a reboot is needed\n"); page->flags &= ~(1 << PG_lru | 1 << PG_private | 1 << PG_locked | @@ -194,19 +194,15 @@ static void destroy_compound_page(struct page *page, unsigned long order) int i; int nr_pages = 1 << order; - if (!PageCompound(page)) - return; - - if (page[1].index != order) - bad_page(__FUNCTION__, page); + if (unlikely(page[1].index != order)) + bad_page(page); for (i = 0; i < nr_pages; i++) { struct page *p = page + i; - if (!PageCompound(p)) - bad_page(__FUNCTION__, page); - if (page_private(p) != (unsigned long)page) - bad_page(__FUNCTION__, page); + if (unlikely(!PageCompound(p) | + (page_private(p) != (unsigned long)page))) + bad_page(page); ClearPageCompound(p); } } @@ -316,7 +312,7 @@ static inline void __free_pages_bulk (struct page *page, unsigned long page_idx; int order_size = 1 << order; - if (unlikely(order)) + if (unlikely(PageCompound(page))) destroy_compound_page(page, order); page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1); @@ -348,7 +344,7 @@ static inline void __free_pages_bulk (struct page *page, zone->free_area[order].nr_free++; } -static inline int free_pages_check(const char *function, struct page *page) +static inline int free_pages_check(struct page *page) { if (unlikely(page_mapcount(page) | (page->mapping != NULL) | @@ -363,7 +359,7 @@ static inline int free_pages_check(const char *function, struct page *page) 1 << PG_swapcache | 1 << PG_writeback | 1 << PG_reserved )))) - bad_page(function, page); + bad_page(page); if (PageDirty(page)) __ClearPageDirty(page); /* @@ -422,7 +418,7 @@ void __free_pages_ok(struct page *page, unsigned int order) #endif for (i = 0 ; i < (1 << order) ; ++i) - reserved += free_pages_check(__FUNCTION__, page + i); + reserved += free_pages_check(page + i); if (reserved) return; @@ -517,7 +513,7 @@ static int prep_new_page(struct page *page, int order) 1 << PG_swapcache | 1 << PG_writeback | 1 << PG_reserved )))) - bad_page(__FUNCTION__, page); + bad_page(page); /* * For now, we report if PG_reserved was found set, but do not @@ -716,7 +712,7 @@ static void fastcall free_hot_cold_page(struct page *page, int cold) if (PageAnon(page)) page->mapping = NULL; - if (free_pages_check(__FUNCTION__, page)) + if (free_pages_check(page)) return; inc_page_state(pgfree);