From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx> Subject: mm: align struct page more aesthetically Patch series "Restructure struct page", v2. This series does not attempt any grand restructuring. Instead, it cures the worst of the indentitis, fixes the documentation and reduces the ifdeffery. The only layout change is compound_dtor and compound_order are each reduced to one byte. This patch (of 8): Instead of an ifdef block at the end of the struct, which needed its own comment, define _struct_page_alignment up at the top where it fits nicely with the existing comment. Link: http://lkml.kernel.org/r/20171220155552.15884-2-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Christoph Lameter <cl@xxxxxxxxx> Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mm_types.h | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff -puN include/linux/mm_types.h~mm-align-struct-page-more-aesthetically include/linux/mm_types.h --- a/include/linux/mm_types.h~mm-align-struct-page-more-aesthetically +++ a/include/linux/mm_types.h @@ -39,6 +39,12 @@ struct hmm; * allows the use of atomic double word operations on the flags/mapping * and lru list pointers also. */ +#ifdef CONFIG_HAVE_ALIGNED_STRUCT_PAGE +#define _struct_page_alignment __aligned(2 * sizeof(unsigned long)) +#else +#define _struct_page_alignment +#endif + struct page { /* First double word block */ unsigned long flags; /* Atomic flags, some possibly @@ -212,15 +218,7 @@ struct page { #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS int _last_cpupid; #endif -} -/* - * The struct page can be forced to be double word aligned so that atomic ops - * on double words work. The SLUB allocator can make use of such a feature. - */ -#ifdef CONFIG_HAVE_ALIGNED_STRUCT_PAGE - __aligned(2 * sizeof(unsigned long)) -#endif -; +} _struct_page_alignment; #define PAGE_FRAG_CACHE_MAX_SIZE __ALIGN_MASK(32768, ~PAGE_MASK) #define PAGE_FRAG_CACHE_MAX_ORDER get_order(PAGE_FRAG_CACHE_MAX_SIZE) _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
