staging: ramster: Provide accessory functions for counter decrease

This patch enables these functions to be wrapped and
can disable/enable this with CONFIG_DEBUG_FS.

Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/zcache/ramster/ramster.c

@@ -73,6 +73,10 @@ static inline void inc_ramster_flnodes(void)
 	if (ramster_flnodes > ramster_flnodes_max)
 		ramster_flnodes_max = ramster_flnodes;
 }
+static inline void dec_ramster_flnodes(void)
+{
+	ramster_flnodes = atomic_dec_return(&ramster_flnodes_atomic);
+}
 static ssize_t ramster_foreign_eph_pages;
 static atomic_t ramster_foreign_eph_pages_atomic = ATOMIC_INIT(0);
 static ssize_t ramster_foreign_eph_pages_max;
@@ -83,6 +87,11 @@ static inline void inc_ramster_foreign_eph_pages(void)
 	if (ramster_foreign_eph_pages > ramster_foreign_eph_pages_max)
 		ramster_foreign_eph_pages_max = ramster_foreign_eph_pages;
 }
+static inline void dec_ramster_foreign_eph_pages(void)
+{
+	ramster_foreign_eph_pages = atomic_dec_return(
+			&ramster_foreign_eph_pages_atomic);
+}
 static ssize_t ramster_foreign_pers_pages;
 static atomic_t ramster_foreign_pers_pages_atomic = ATOMIC_INIT(0);
 static ssize_t ramster_foreign_pers_pages_max;
@@ -93,6 +102,11 @@ static inline void inc_ramster_foreign_pers_pages(void)
 	if (ramster_foreign_pers_pages > ramster_foreign_pers_pages_max)
 		ramster_foreign_pers_pages_max = ramster_foreign_pers_pages;
 }
+static inline void dec_ramster_foreign_pers_pages(void)
+{
+	ramster_foreign_pers_pages = atomic_dec_return(
+		&ramster_foreign_pers_pages_atomic);
+}
 static ssize_t ramster_eph_pages_remoted;
 static ssize_t ramster_pers_pages_remoted;
 static ssize_t ramster_eph_pages_remote_failed;
@@ -188,10 +202,8 @@ static struct flushlist_node *ramster_flnode_alloc(struct tmem_pool *pool)
 static void ramster_flnode_free(struct flushlist_node *flnode,
 				struct tmem_pool *pool)
 {
-	int flnodes;
-
-	flnodes = atomic_dec_return(&ramster_flnodes_atomic);
-	BUG_ON(flnodes < 0);
+	dec_ramster_flnodes();
+	BUG_ON(ramster_flnodes < 0);
 	kmem_cache_free(ramster_flnode_cache, flnode);
 }
 
@@ -484,26 +496,20 @@ void *ramster_pampd_free(void *pampd, struct tmem_pool *pool,
 
 void ramster_count_foreign_pages(bool eph, int count)
 {
-	int c;
-
 	BUG_ON(count != 1 && count != -1);
 	if (eph) {
 		if (count > 0) {
 			inc_ramster_foreign_eph_pages();
 		} else {
-			c = atomic_dec_return(&ramster_foreign_eph_pages_atomic);
-			WARN_ON_ONCE(c < 0);
+			dec_ramster_foreign_eph_pages();
+			WARN_ON_ONCE(ramster_foreign_eph_pages < 0);
 		}
-		ramster_foreign_eph_pages = c;
 	} else {
 		if (count > 0) {
 			inc_ramster_foreign_pers_pages();
 		} else {
-			c = atomic_dec_return(
-					&ramster_foreign_pers_pages_atomic);
-			WARN_ON_ONCE(c < 0);
+			WARN_ON_ONCE(ramster_foreign_pers_pages < 0);
 		}
-		ramster_foreign_pers_pages = c;
 	}
 }