dhugetlb: use enable_dhugetlb to disable huge_memory

hulk inclusion
category: feature
bugzilla: 46904, https://gitee.com/openeuler/kernel/issues/I6BDME
CVE: NA

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

If hugepage_init() is called before hugetlb_init(), dhugetlb_enabled
has not been initialized, we should use enable_dhugetlb instead.
Signed-off-by: NLiu Shixin <liushixin2@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NYongqiang Liu <liuyongqiang13@huawei.com>

include/linux/hugetlb.h

@@ -668,6 +668,7 @@ static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr
 /* We don't need to try 5 times, or we can't migrate the pages. */
 #define HPOOL_RECLAIM_RETRIES	5
 
+extern bool enable_dhugetlb;
 extern struct static_key_false dhugetlb_enabled_key;
 #define dhugetlb_enabled (static_branch_unlikely(&dhugetlb_enabled_key))
 
@@ -744,7 +745,8 @@ void move_pages_from_smpool_to_hpool(struct dhugetlb_pool *hpool,
 void dhugetlb_reserve_hugepages(struct dhugetlb_pool *hpool,
 				unsigned long count, bool gigantic);
 #else
-#define dhugetlb_enabled       0
+#define enable_dhugetlb		0
+#define dhugetlb_enabled	0
 struct dhugetlb_pool {};
 static inline struct dhugetlb_pool *get_dhugetlb_pool_from_task(
 						struct task_struct *tsk)

mm/huge_memory.c

@@ -404,9 +404,9 @@ static int __init hugepage_init(void)
 	 * use transparent hugepage in addition.
 	 * (May result negative optimization)
 	 */
-	if (dhugetlb_enabled) {
+	if (enable_dhugetlb) {
 		transparent_hugepage_flags = 0;
-		pr_info("transparent hugepage is disabled due to confilct with dynamic hugetlb\n");
+		pr_info("transparent hugepage is disabled due to conflict with dynamic hugetlb\n");
 		return -EINVAL;
 	}
 

mm/hugetlb.c

@@ -3299,7 +3299,7 @@ static void hugetlb_register_all_nodes(void) { }
 #endif
 
 #ifdef CONFIG_DYNAMIC_HUGETLB
-static bool enable_dhugetlb;
+bool enable_dhugetlb;
 DEFINE_STATIC_KEY_FALSE(dhugetlb_enabled_key);
 DEFINE_RWLOCK(dhugetlb_pagelist_rwlock);
 struct dhugetlb_pagelist *dhugetlb_pagelist_t;