Minor source code cleanup of page flags in mm/page_alloc.c. Move the definition of the groups of bits to page-flags.h. The purpose of this clean up is that the next patch will conditionally add a page flag to the groups. Doing that in a header file is cleaner than adding #ifdefs to the C code. Signed-off-by: Russ Anderson <rja@xxxxxxx> --- include/linux/page-flags.h | 24 ++++++++++++++++++++++++ mm/page_alloc.c | 34 +++------------------------------- 2 files changed, 27 insertions(+), 31 deletions(-) Index: linux-next/mm/page_alloc.c =================================================================== --- linux-next.orig/mm/page_alloc.c 2008-06-09 09:26:47.542997555 -0500 +++ linux-next/mm/page_alloc.c 2008-06-09 09:26:52.203578218 -0500 @@ -237,16 +237,7 @@ static void bad_page(struct page *page) printk(KERN_EMERG "Trying to fix it up, but a reboot is needed\n" KERN_EMERG "Backtrace:\n"); dump_stack(); - page->flags &= ~(1 << PG_lru | - 1 << PG_private | - 1 << PG_locked | - 1 << PG_active | - 1 << PG_dirty | - 1 << PG_reclaim | - 1 << PG_slab | - 1 << PG_swapcache | - 1 << PG_writeback | - 1 << PG_buddy ); + page->flags &= ~PAGE_FLAGS_CLEAR_WHEN_BAD; set_page_count(page, 0); reset_page_mapcount(page); page->mapping = NULL; @@ -463,16 +454,7 @@ static inline int free_pages_check(struc (page->mapping != NULL) | (page_get_page_cgroup(page) != NULL) | (page_count(page) != 0) | - (page->flags & ( - 1 << PG_lru | - 1 << PG_private | - 1 << PG_locked | - 1 << PG_active | - 1 << PG_slab | - 1 << PG_swapcache | - 1 << PG_writeback | - 1 << PG_reserved | - 1 << PG_buddy )))) + (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) bad_page(page); if (PageDirty(page)) __ClearPageDirty(page); @@ -616,17 +598,7 @@ static int prep_new_page(struct page *pa (page->mapping != NULL) | (page_get_page_cgroup(page) != NULL) | (page_count(page) != 0) | - (page->flags & ( - 1 << PG_lru | - 1 << PG_private | - 1 << PG_locked | - 1 << PG_active | - 1 << PG_dirty | - 1 << PG_slab | - 1 << PG_swapcache | - 1 << PG_writeback | - 1 << PG_reserved | - 1 << PG_buddy )))) + (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) bad_page(page); /* Index: linux-next/include/linux/page-flags.h =================================================================== --- linux-next.orig/include/linux/page-flags.h 2008-06-09 09:26:47.546998054 -0500 +++ linux-next/include/linux/page-flags.h 2008-06-09 09:26:52.223580710 -0500 @@ -307,5 +307,29 @@ static inline void __ClearPageTail(struc } #endif /* !PAGEFLAGS_EXTENDED */ + +#define PAGE_FLAGS (1 << PG_lru | 1 << PG_private | 1 << PG_locked | \ + 1 << PG_buddy | 1 << PG_writeback | \ + 1 << PG_slab | 1 << PG_swapcache | 1 << PG_active) + +/* + * Flags checked in bad_page(). Pages on the free list should not have + * these flags set. It they are, there is a problem. + */ +#define PAGE_FLAGS_CLEAR_WHEN_BAD (PAGE_FLAGS | 1 << PG_reclaim | 1 << PG_dirty) + +/* + * Flags checked when a page is freed. Pages being freed should not have + * these flags set. It they are, there is a problem. + */ +#define PAGE_FLAGS_CHECK_AT_FREE (PAGE_FLAGS | 1 << PG_reserved) + +/* + * Flags checked when a page is prepped for return by the page allocator. + * Pages being prepped should not have these flags set. It they are, there + * is a problem. + */ +#define PAGE_FLAGS_CHECK_AT_PREP (PAGE_FLAGS | 1 << PG_reserved | 1 << PG_dirty) + #endif /* !__GENERATING_BOUNDS_H */ #endif /* PAGE_FLAGS_H */ -- Russ Anderson, OS RAS/Partitioning Project Lead SGI - Silicon Graphics Inc rja@xxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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