[RFC PATCH 06/16] mm: Define function to create a dir for each page order

[Juan Yescas <jyescas@google.com>]

This change creates a directory for each page order inside
the zone directory.

Signed-off-by: Juan Yescas <jyescas@google.com>
---
 mm/page_alloc_hogger.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/mm/page_alloc_hogger.c b/mm/page_alloc_hogger.c
index 1cec9ec5e35e..de86b8526338 100644
--- a/mm/page_alloc_hogger.c
+++ b/mm/page_alloc_hogger.c
@@ -127,6 +127,28 @@ struct page_alloc {
 struct kmem_cache *req_alloc_cache;
 struct kmem_cache *page_alloc_cache;
 
+/**
+ * create_page_orders_subdirs() - Creates a directory for each page order inside
+ * the zone directory. Once that the page order directory is created, it creates
+ * a directory for each migrate type.
+ */
+static inline int create_page_orders_subdirs(struct dentry *zonedir,
+					     int node_idx, int zone_idx,
+					     struct zone *zone)
+{
+	struct dentry *orderdir;
+	char dirname[12];
+
+	for (int order = 0; order < NR_PAGE_ORDERS; order++) {
+		snprintf(dirname, sizeof(dirname), "order-%d", order);
+		orderdir = debugfs_create_dir(dirname, zonedir);
+		if (IS_ERR(orderdir))
+			return PTR_ERR(orderdir);
+	}
+
+	return 0;
+}
+
 /**
  * create_zones_subdirs() - Creates a directory for each populated zone in the
  * node. Once that the zone directory is created, it creates a directory for
@@ -143,6 +165,7 @@ static inline int create_zones_subdirs(struct dentry *nodedir, int node_idx,
 	struct zone *node_zones = pgdata->node_zones;
 	int zone_idx;
 	char dirname[24];
+	int ret;
 
 	for (zone = node_zones, zone_idx = 0; zone - node_zones < MAX_NR_ZONES;
 	     ++zone, ++zone_idx) {
@@ -157,6 +180,11 @@ static inline int create_zones_subdirs(struct dentry *nodedir, int node_idx,
 		zonedir = debugfs_create_dir(dirname, nodedir);
 		if (IS_ERR(zonedir))
 			return PTR_ERR(zonedir);
+
+		ret = create_page_orders_subdirs(zonedir, node_idx, zone_idx,
+						 zone);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
-- 
2.55.0.229.g6434b31f56-goog