This flag shows that a given pages is a subpage of transparent hugepage. It does not care about whether it is a head page or a tail page, because it's clear from pfn of the target page which you should know when you read /proc/kpageflags. Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> --- fs/proc/page.c | 5 +++++ include/linux/kernel-page-flags.h | 4 ++++ 2 files changed, 9 insertions(+), 0 deletions(-) diff --git 3.2-rc5.orig/fs/proc/page.c 3.2-rc5/fs/proc/page.c index 6d8e6a9..d436fc6 100644 --- 3.2-rc5.orig/fs/proc/page.c +++ 3.2-rc5/fs/proc/page.c @@ -116,6 +116,11 @@ u64 stable_page_flags(struct page *page) if (PageHuge(page)) u |= 1 << KPF_HUGE; +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (PageTransCompound(page)) + u |= 1 << KPF_THP; +#endif + /* * Caveats on high order pages: page->_count will only be set * -1 on the head page; SLUB/SLQB do the same for PG_slab; diff --git 3.2-rc5.orig/include/linux/kernel-page-flags.h 3.2-rc5/include/linux/kernel-page-flags.h index bd92a89..7b83ee7 100644 --- 3.2-rc5.orig/include/linux/kernel-page-flags.h +++ 3.2-rc5/include/linux/kernel-page-flags.h @@ -31,6 +31,10 @@ #define KPF_KSM 21 +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#define KPF_THP 22 +#endif + /* kernel hacking assistances * WARNING: subject to change, never rely on them! */ -- 1.7.7.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>