From 807f0ccfe15551afd514c062585045c88ca62037 Mon Sep 17 00:00:00 2001 From: Naoya Horiguchi Date: Wed, 21 Mar 2012 16:33:58 -0700 Subject: [PATCH] pagemap: document KPF_THP and make page-types aware of it page-types, which is a common user of pagemap, gets aware of thp with this patch. This helps system admins and kernel hackers know about how thp works. Here is a sample output of page-types over a thp: $ page-types -p --raw --list voffset offset len flags ... 7f9d40200 3f8400 1 ___U_lA____Ma_bH______t____________ 7f9d40201 3f8401 1ff ________________T_____t____________ flags page-count MB symbolic-flags long-symbolic-flags 0x0000000000410000 511 1 ________________T_____t____________ compound_tail,thp 0x000000000040d868 1 0 ___U_lA____Ma_bH______t____________ uptodate,lru,active,mmap,anonymous,swapbacked,compound_head,thp Signed-off-by: Naoya Horiguchi Acked-by: Wu Fengguang Reviewed-by: KAMEZAWA Hiroyuki Acked-by: KOSAKI Motohiro Cc: David Rientjes Cc: Andi Kleen Cc: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/vm/page-types.c | 2 ++ Documentation/vm/pagemap.txt | 4 ++++ 2 files changed, 6 insertions(+) diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c index 7445caa26d05..0b13f02d4059 100644 --- a/Documentation/vm/page-types.c +++ b/Documentation/vm/page-types.c @@ -98,6 +98,7 @@ #define KPF_HWPOISON 19 #define KPF_NOPAGE 20 #define KPF_KSM 21 +#define KPF_THP 22 /* [32-] kernel hacking assistances */ #define KPF_RESERVED 32 @@ -147,6 +148,7 @@ static const char *page_flag_names[] = { [KPF_HWPOISON] = "X:hwpoison", [KPF_NOPAGE] = "n:nopage", [KPF_KSM] = "x:ksm", + [KPF_THP] = "t:thp", [KPF_RESERVED] = "r:reserved", [KPF_MLOCKED] = "m:mlocked", diff --git a/Documentation/vm/pagemap.txt b/Documentation/vm/pagemap.txt index df09b9650a81..4600cbe3d6be 100644 --- a/Documentation/vm/pagemap.txt +++ b/Documentation/vm/pagemap.txt @@ -60,6 +60,7 @@ There are three components to pagemap: 19. HWPOISON 20. NOPAGE 21. KSM + 22. THP Short descriptions to the page flags: @@ -97,6 +98,9 @@ Short descriptions to the page flags: 21. KSM identical memory pages dynamically shared between one or more processes +22. THP + contiguous pages which construct transparent hugepages + [IO related page flags] 1. ERROR IO error occurred 3. UPTODATE page has up-to-date data