mm, rmap: account shmem thp pages

Let's add ShmemHugePages and ShmemPmdMapped fields into meminfo and
smaps.  It indicates how many times we allocate and map shmem THP.

NR_ANON_TRANSPARENT_HUGEPAGES is renamed to NR_ANON_THPS.

Link: http://lkml.kernel.org/r/1466021202-61880-27-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 847281e..452513b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4312,6 +4312,9 @@
 		" unevictable:%lu dirty:%lu writeback:%lu unstable:%lu\n"
 		" slab_reclaimable:%lu slab_unreclaimable:%lu\n"
 		" mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n"
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+		" anon_thp: %lu shmem_thp: %lu shmem_pmdmapped: %lu\n"
+#endif
 		" free:%lu free_pcp:%lu free_cma:%lu\n",
 		global_page_state(NR_ACTIVE_ANON),
 		global_page_state(NR_INACTIVE_ANON),
@@ -4329,6 +4332,11 @@
 		global_page_state(NR_SHMEM),
 		global_page_state(NR_PAGETABLE),
 		global_page_state(NR_BOUNCE),
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+		global_page_state(NR_ANON_THPS) * HPAGE_PMD_NR,
+		global_page_state(NR_SHMEM_THPS) * HPAGE_PMD_NR,
+		global_page_state(NR_SHMEM_PMDMAPPED) * HPAGE_PMD_NR,
+#endif
 		global_page_state(NR_FREE_PAGES),
 		free_pcp,
 		global_page_state(NR_FREE_CMA_PAGES));
@@ -4363,6 +4371,11 @@
 			" writeback:%lukB"
 			" mapped:%lukB"
 			" shmem:%lukB"
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+			" shmem_thp: %lukB"
+			" shmem_pmdmapped: %lukB"
+			" anon_thp: %lukB"
+#endif
 			" slab_reclaimable:%lukB"
 			" slab_unreclaimable:%lukB"
 			" kernel_stack:%lukB"
@@ -4395,6 +4408,12 @@
 			K(zone_page_state(zone, NR_WRITEBACK)),
 			K(zone_page_state(zone, NR_FILE_MAPPED)),
 			K(zone_page_state(zone, NR_SHMEM)),
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+			K(zone_page_state(zone, NR_SHMEM_THPS) * HPAGE_PMD_NR),
+			K(zone_page_state(zone, NR_SHMEM_PMDMAPPED)
+					* HPAGE_PMD_NR),
+			K(zone_page_state(zone, NR_ANON_THPS) * HPAGE_PMD_NR),
+#endif
 			K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
 			K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
 			zone_page_state(zone, NR_KERNEL_STACK) *