[RFC][PATCH v2 05/21] mmzone: new pgdat flags for DRAM and PMEM

[Fengguang Wu]

From: Fan Du <fan.du@xxxxxxxxx>

One system with DRAM and PMEM, we need new flag
to tag pgdat is made of DRAM or peristent memory.

This patch serves as preparetion one for follow up patch.

Signed-off-by: Fan Du <fan.du@xxxxxxxxx>
Signed-off-by: Fengguang Wu <fengguang.wu@xxxxxxxxx>
---
 include/linux/mmzone.h |   26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

--- linux.orig/include/linux/mmzone.h	2018-12-23 19:29:42.430602202 +0800
+++ linux/include/linux/mmzone.h	2018-12-23 19:29:42.430602202 +0800
@@ -522,6 +522,8 @@ enum pgdat_flags {
 					 * many pages under writeback
 					 */
 	PGDAT_RECLAIM_LOCKED,		/* prevents concurrent reclaim */
+	PGDAT_DRAM,			/* Volatile DRAM memory node */
+	PGDAT_PMEM,			/* Persistent memory node */
 };
 
 static inline unsigned long zone_end_pfn(const struct zone *zone)
@@ -919,6 +921,30 @@ extern struct pglist_data contig_page_da
 
 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 
+static inline int is_node_pmem(int nid)
+{
+	pg_data_t *pgdat = NODE_DATA(nid);
+
+	return test_bit(PGDAT_PMEM, &pgdat->flags);
+}
+
+static inline int is_node_dram(int nid)
+{
+	pg_data_t *pgdat = NODE_DATA(nid);
+
+	return test_bit(PGDAT_DRAM, &pgdat->flags);
+}
+
+static inline void set_node_type(int nid)
+{
+	pg_data_t *pgdat = NODE_DATA(nid);
+
+	if (node_isset(nid, numa_nodes_pmem))
+		set_bit(PGDAT_PMEM, &pgdat->flags);
+	else
+		set_bit(PGDAT_DRAM, &pgdat->flags);
+}
+
 extern struct pglist_data *first_online_pgdat(void);
 extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
 extern struct zone *next_zone(struct zone *zone);