mm: Add reliable_nr_page for accounting reliable memory

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4SK3S
CVE: NA

--------------------------------

Adding an variable in mm_struct for accouting the amount of reliable memory
allocated by the reliable user tasks.
Signed-off-by: NPeng Wu <wupeng58@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>

include/linux/mm_types.h

@@ -587,7 +587,8 @@ struct mm_struct {
 #endif
 
 #ifdef CONFIG_MEMORY_RELIABLE
-		atomic_long_t reserve_0;
+		/* total used reliable pages */
+		KABI_RENAME(atomic_long_t reserve_0, atomic_long_t reliable_nr_page);
 #endif
 	} __randomize_layout;