thp: transparent hugepage vmstat

Add hugepage stat information to /proc/vmstat and /proc/meminfo.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/proc/meminfo.c

@@ -100,6 +100,9 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 		"VmallocChunk:   %8lu kB\n"
 #ifdef CONFIG_MEMORY_FAILURE
 		"HardwareCorrupted: %5lu kB\n"
+#endif
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+		"AnonHugePages:  %8lu kB\n"
 #endif
 		,
 		K(i.totalram),
@@ -128,7 +131,12 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 		K(i.freeswap),
 		K(global_page_state(NR_FILE_DIRTY)),
 		K(global_page_state(NR_WRITEBACK)),
-		K(global_page_state(NR_ANON_PAGES)),
+		K(global_page_state(NR_ANON_PAGES)
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+		  + global_page_state(NR_ANON_TRANSPARENT_HUGEPAGES) *
+		  HPAGE_PMD_NR
+#endif
+		  ),
 		K(global_page_state(NR_FILE_MAPPED)),
 		K(global_page_state(NR_SHMEM)),
 		K(global_page_state(NR_SLAB_RECLAIMABLE) +
@@ -150,6 +158,10 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 		vmi.largest_chunk >> 10
 #ifdef CONFIG_MEMORY_FAILURE
 		,atomic_long_read(&mce_bad_pages) << (PAGE_SHIFT - 10)
+#endif
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+		,K(global_page_state(NR_ANON_TRANSPARENT_HUGEPAGES) *
+		   HPAGE_PMD_NR)
 #endif
 		);
 

include/linux/mmzone.h

@@ -114,6 +114,7 @@ enum zone_stat_item {
 	NUMA_LOCAL,		/* allocation from local node */
 	NUMA_OTHER,		/* allocation from other node */
 #endif
+	NR_ANON_TRANSPARENT_HUGEPAGES,
 	NR_VM_ZONE_STAT_ITEMS };
 
 /*

mm/huge_memory.c

@@ -751,6 +751,9 @@ static void __split_huge_page_refcount(struct page *page)
 		lru_add_page_tail(zone, page, page_tail);
 	}
 
+	__dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES);
+	__mod_zone_page_state(zone, NR_ANON_PAGES, HPAGE_PMD_NR);
+
 	ClearPageCompound(page);
 	compound_unlock(page);
 	spin_unlock_irq(&zone->lru_lock);

mm/rmap.c

@@ -882,8 +882,13 @@ void do_page_add_anon_rmap(struct page *page,
 	struct vm_area_struct *vma, unsigned long address, int exclusive)
 {
 	int first = atomic_inc_and_test(&page->_mapcount);
-	if (first)
+	if (first) {
+		if (!PageTransHuge(page))
 			__inc_zone_page_state(page, NR_ANON_PAGES);
+		else
+			__inc_zone_page_state(page,
+					      NR_ANON_TRANSPARENT_HUGEPAGES);
+	}
 	if (unlikely(PageKsm(page)))
 		return;
 
@@ -911,7 +916,10 @@ void page_add_new_anon_rmap(struct page *page,
 	VM_BUG_ON(address < vma->vm_start || address >= vma->vm_end);
 	SetPageSwapBacked(page);
 	atomic_set(&page->_mapcount, 0); /* increment count (starts at -1) */
+	if (!PageTransHuge(page))
 		__inc_zone_page_state(page, NR_ANON_PAGES);
+	else
+		__inc_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES);
 	__page_set_anon_rmap(page, vma, address, 1);
 	if (page_evictable(page, vma))
 		lru_cache_add_lru(page, LRU_ACTIVE_ANON);
@@ -964,7 +972,11 @@ void page_remove_rmap(struct page *page)
 		return;
 	if (PageAnon(page)) {
 		mem_cgroup_uncharge_page(page);
+		if (!PageTransHuge(page))
 			__dec_zone_page_state(page, NR_ANON_PAGES);
+		else
+			__dec_zone_page_state(page,
+					      NR_ANON_TRANSPARENT_HUGEPAGES);
 	} else {
 		__dec_zone_page_state(page, NR_FILE_MAPPED);
 		mem_cgroup_update_file_mapped(page, -1);

mm/vmstat.c

@@ -880,6 +880,7 @@ static const char * const vmstat_text[] = {
 	"numa_local",
 	"numa_other",
 #endif
+	"nr_anon_transparent_hugepages",
 	"nr_dirty_threshold",
 	"nr_dirty_background_threshold",