[PATCH 19/49] mm/sparse-vmemmap: remove the VMEMMAP_POPULATE_PAGEREF flag

[Muchun Song]

The VMEMMAP_POPULATE_PAGEREF flag is only used to ensure that we call
get_page() when slab is available, as mentioned in the comment:
"and through vmemmap_populate_compound_pages() when slab is available".

Since we can check slab_is_available() directly, the flag and the
associated argument passing can be removed to simplify the code.

Signed-off-by: Muchun Song <songmuchun at bytedance.com>
---
 mm/sparse-vmemmap.c | 40 ++++++++++++++--------------------------
 1 file changed, 14 insertions(+), 26 deletions(-)

diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 26cb55c12a83..3fdb6808e8ab 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -33,13 +33,6 @@
 #include <asm/tlbflush.h>
 
 #include "hugetlb_vmemmap.h"
-
-/*
- * Flags for vmemmap_populate_range and friends.
- */
-/* Get a ref on the head page struct page, for ZONE_DEVICE compound pages */
-#define VMEMMAP_POPULATE_PAGEREF	0x0001
-
 #include "internal.h"
 
 /*
@@ -152,8 +145,8 @@ void __meminit vmemmap_verify(pte_t *pte, int node,
 }
 
 static pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
-				       struct vmem_altmap *altmap,
-				       unsigned long ptpfn, unsigned long flags)
+					      struct vmem_altmap *altmap,
+					      unsigned long ptpfn)
 {
 	pte_t *pte = pte_offset_kernel(pmd, addr);
 	if (pte_none(ptep_get(pte))) {
@@ -175,7 +168,7 @@ static pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, in
 			 * and through vmemmap_populate_compound_pages() when
 			 * slab is available.
 			 */
-			if (flags & VMEMMAP_POPULATE_PAGEREF)
+			if (slab_is_available())
 				get_page(pfn_to_page(ptpfn));
 		}
 		entry = pfn_pte(ptpfn, PAGE_KERNEL);
@@ -248,8 +241,7 @@ static pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
 
 static pte_t * __meminit vmemmap_populate_address(unsigned long addr, int node,
 					      struct vmem_altmap *altmap,
-					      unsigned long ptpfn,
-					      unsigned long flags)
+					      unsigned long ptpfn)
 {
 	pgd_t *pgd;
 	p4d_t *p4d;
@@ -269,7 +261,7 @@ static pte_t * __meminit vmemmap_populate_address(unsigned long addr, int node,
 	pmd = vmemmap_pmd_populate(pud, addr, node);
 	if (!pmd)
 		return NULL;
-	pte = vmemmap_pte_populate(pmd, addr, node, altmap, ptpfn, flags);
+	pte = vmemmap_pte_populate(pmd, addr, node, altmap, ptpfn);
 	if (!pte)
 		return NULL;
 	vmemmap_verify(pte, node, addr, addr + PAGE_SIZE);
@@ -280,15 +272,14 @@ static pte_t * __meminit vmemmap_populate_address(unsigned long addr, int node,
 static int __meminit vmemmap_populate_range(unsigned long start,
 					    unsigned long end, int node,
 					    struct vmem_altmap *altmap,
-					    unsigned long ptpfn,
-					    unsigned long flags)
+					    unsigned long ptpfn)
 {
 	unsigned long addr = start;
 	pte_t *pte;
 
 	for (; addr < end; addr += PAGE_SIZE) {
 		pte = vmemmap_populate_address(addr, node, altmap,
-					       ptpfn, flags);
+					       ptpfn);
 		if (!pte)
 			return -ENOMEM;
 	}
@@ -306,7 +297,7 @@ int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end,
 {
 	if (vmemmap_can_optimize(altmap, pgmap))
 		return vmemmap_populate_compound_pages(start, end, node, pgmap);
-	return vmemmap_populate_range(start, end, node, altmap, -1, 0);
+	return vmemmap_populate_range(start, end, node, altmap, -1);
 }
 
 /*
@@ -382,7 +373,7 @@ int __meminit vmemmap_populate_hvo(unsigned long addr, unsigned long end,
 		return -ENOMEM;
 
 	for (maddr = addr; maddr < addr + headsize; maddr += PAGE_SIZE) {
-		pte = vmemmap_populate_address(maddr, node, NULL, -1, 0);
+		pte = vmemmap_populate_address(maddr, node, NULL, -1);
 		if (!pte)
 			return -ENOMEM;
 	}
@@ -390,8 +381,7 @@ int __meminit vmemmap_populate_hvo(unsigned long addr, unsigned long end,
 	/*
 	 * Reuse the last page struct page mapped above for the rest.
 	 */
-	return vmemmap_populate_range(maddr, end, node, NULL,
-				      page_to_pfn(tail), 0);
+	return vmemmap_populate_range(maddr, end, node, NULL, page_to_pfn(tail));
 }
 #endif
 
@@ -518,8 +508,7 @@ static int __meminit vmemmap_populate_compound_pages(unsigned long start,
 		 * with just tail struct pages.
 		 */
 		return vmemmap_populate_range(start, end, node, NULL,
-					      pte_pfn(ptep_get(pte)),
-					      VMEMMAP_POPULATE_PAGEREF);
+					      pte_pfn(ptep_get(pte)));
 	}
 
 	size = min(end - start, pgmap_vmemmap_nr(pgmap) * sizeof(struct page));
@@ -527,13 +516,13 @@ static int __meminit vmemmap_populate_compound_pages(unsigned long start,
 		unsigned long next, last = addr + size;
 
 		/* Populate the head page vmemmap page */
-		pte = vmemmap_populate_address(addr, node, NULL, -1, 0);
+		pte = vmemmap_populate_address(addr, node, NULL, -1);
 		if (!pte)
 			return -ENOMEM;
 
 		/* Populate the tail pages vmemmap page */
 		next = addr + PAGE_SIZE;
-		pte = vmemmap_populate_address(next, node, NULL, -1, 0);
+		pte = vmemmap_populate_address(next, node, NULL, -1);
 		if (!pte)
 			return -ENOMEM;
 
@@ -543,8 +532,7 @@ static int __meminit vmemmap_populate_compound_pages(unsigned long start,
 		 */
 		next += PAGE_SIZE;
 		rc = vmemmap_populate_range(next, last, node, NULL,
-					    pte_pfn(ptep_get(pte)),
-					    VMEMMAP_POPULATE_PAGEREF);
+					    pte_pfn(ptep_get(pte)));
 		if (rc)
 			return -ENOMEM;
 	}
-- 
2.20.1