Ascend/hugetlb:support alloc normal and buddy hugepage

ascend inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4D63I
CVE: NA

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

The current function hugetlb_alloc_hugepage implements the allocation
from static hugepages first. When the static hugepage is used up, it
attempts to apply for hugepages from buddy system. Two additional modes
are supported: static hugepages only and buddy hugepages only.
Signed-off-by: NZhou Guanghui <zhouguanghui1@huawei.com>
Signed-off-by: NGuo Mengqi <guomengqi3@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

include/linux/hugetlb.h

@@ -374,8 +374,15 @@ int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
 			pgoff_t idx);
 
 #ifdef CONFIG_ASCEND_FEATURES
+#define HUGETLB_ALLOC_NONE             0x00
+#define HUGETLB_ALLOC_NORMAL           0x01    /* normal hugepage */
+#define HUGETLB_ALLOC_BUDDY            0x02    /* buddy hugepage */
+#define HUGETLB_ALLOC_MASK             (HUGETLB_ALLOC_NONE | \
+                                        HUGETLB_ALLOC_NORMAL | \
+                                        HUGETLB_ALLOC_BUDDY)
+
 const struct hstate *hugetlb_get_hstate(void);
-struct page *hugetlb_alloc_hugepage(int nid);
+struct page *hugetlb_alloc_hugepage(int nid, int flag);
 int hugetlb_insert_hugepage_pte(struct mm_struct *mm, unsigned long addr,
 			      pgprot_t prot, struct page *hpage);
 #else
@@ -384,7 +391,7 @@ static inline const struct hstate *hugetlb_get_hstate(void)
 	return NULL;
 }
 
-static inline struct page *hugetlb_alloc_hugepage(int nid)
+static inline struct page *hugetlb_alloc_hugepage(int nid, int flag)
 {
 	return  NULL;
 }

mm/hugetlb.c

@@ -5234,17 +5234,48 @@ const struct hstate *hugetlb_get_hstate(void)
 }
 EXPORT_SYMBOL_GPL(hugetlb_get_hstate);
 
+static struct page *hugetlb_alloc_hugepage_normal(struct hstate *h,
+		gfp_t gfp_mask, int nid)
+{
+	struct page *page = NULL;
+
+	spin_lock(&hugetlb_lock);
+	if (h->free_huge_pages - h->resv_huge_pages > 0)
+		page = dequeue_huge_page_nodemask(h, gfp_mask, nid, NULL, NULL);
+	spin_unlock(&hugetlb_lock);
+
+	return page;
+}
+
 /*
  * Allocate hugepage without reserve
  */
-struct page *hugetlb_alloc_hugepage(int nid)
+struct page *hugetlb_alloc_hugepage(int nid, int flag)
 {
+	struct hstate *h = &default_hstate;
+	gfp_t gfp_mask = htlb_alloc_mask(h);
+	struct page *page = NULL;
+
 	VM_WARN_ON(nid < 0 || nid >= MAX_NUMNODES);
 
+	if (flag & ~HUGETLB_ALLOC_MASK)
+		return NULL;
+
 	if (nid == NUMA_NO_NODE)
 		nid = numa_mem_id();
 
-	return alloc_huge_page_node(&default_hstate, nid);
+	gfp_mask |= __GFP_THISNODE;
+
+	if (flag & HUGETLB_ALLOC_NORMAL)
+		page = hugetlb_alloc_hugepage_normal(h, gfp_mask, nid);
+	else if (flag & HUGETLB_ALLOC_BUDDY) {
+		if (enable_charge_mighp)
+			gfp_mask |= __GFP_ACCOUNT;
+		page = alloc_migrate_huge_page(h, gfp_mask, nid, NULL);
+	} else
+		page = alloc_huge_page_node(h, nid);
+
+	return page;
 }
 EXPORT_SYMBOL_GPL(hugetlb_alloc_hugepage);