[RFC PATCH v2 11/19] mm/sparsemem: Use alloc_table() for table allocations

From: Rick Edgecombe
Date: Mon Aug 30 2021 - 20:00:47 EST


In order to support allocating PKS protected page tables for vmememap,
create a new variant of alloc_table(), alloc_table_node() that allows for
allocation of tables from a specific node. Use it when possible for
allocating vmemmap tables.

vmemmap_alloc_block_zero() is currently only used to allocate page
tables, so fold it into a new function, vmemem_alloc_table() that can
be free to call alloc_table_node(). Since it is today only called with
PAGE_SIZE size, drop the size argument.

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
---
arch/x86/mm/pgtable.c | 10 +++++++---
include/asm-generic/pgalloc.h | 2 ++
include/linux/mm.h | 5 +++++
mm/sparse-vmemmap.c | 22 +++++++++++++++-------
4 files changed, 29 insertions(+), 10 deletions(-)

diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index e65d69ad6e0c..006dc4f81f6d 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -41,7 +41,7 @@ static struct grouped_page_cache gpc_pks;
static bool __ro_after_init pks_tables_inited_val;


-struct page *alloc_table(gfp_t gfp)
+struct page *alloc_table_node(gfp_t gfp, int node)
{
struct page *table;

@@ -53,9 +53,9 @@ struct page *alloc_table(gfp_t gfp)
}

if (gfp & GFP_ATOMIC)
- table = get_grouped_page_atomic(numa_node_id(), &gpc_pks);
+ table = get_grouped_page_atomic(node, &gpc_pks);
else
- table = get_grouped_page(numa_node_id(), &gpc_pks);
+ table = get_grouped_page(node, &gpc_pks);
if (!table)
return NULL;
__SetPageTable(table);
@@ -72,6 +72,10 @@ struct page *alloc_table(gfp_t gfp)

return table;
}
+struct page *alloc_table(gfp_t gfp)
+{
+ return alloc_table_node(gfp, numa_node_id());
+}

void free_table(struct page *table_page)
{
diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h
index e576c19abc8c..eb08371db211 100644
--- a/include/asm-generic/pgalloc.h
+++ b/include/asm-generic/pgalloc.h
@@ -14,8 +14,10 @@ static inline struct page *alloc_table(gfp_t gfp)
{
return alloc_page(gfp);
}
+/* alloc_table_node() stub defined in mm.h */
#else /* __HAVE_ARCH_ALLOC_TABLE */
extern struct page *alloc_table(gfp_t gfp);
+extern struct page *alloc_table_node(gfp_t gfp, int node);
#endif /* __HAVE_ARCH_ALLOC_TABLE */

#ifdef __HAVE_ARCH_FREE_TABLE
diff --git a/include/linux/mm.h b/include/linux/mm.h
index ab63d5a201cb..fdb33bc6bba8 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2332,6 +2332,11 @@ static inline void free_table(struct page *table_page)
{
__free_pages(table_page, 0);
}
+
+static inline struct page *alloc_table_node(gfp_t gfp, int node)
+{
+ return alloc_pages_node(node, gfp, 0);
+}
#endif /* CONFIG_PKS_PG_TABLES */

static inline void pgtable_init(void)
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index bdce883f9286..4f479c75cc8d 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -511,13 +511,21 @@ pte_t * __meminit vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
return pte;
}

-static void * __meminit vmemmap_alloc_block_zero(unsigned long size, int node)
+static void * __meminit vmemmap_alloc_table(int node)
{
- void *p = vmemmap_alloc_block(size, node);
+ void *p;
+ if (slab_is_available()) {
+ struct page *page = alloc_table_node(GFP_KERNEL | __GFP_ZERO, node);
+
+ if (!page)
+ return NULL;
+ return page_address(page);
+ }

+ p = __earlyonly_bootmem_alloc(node, PAGE_SIZE, PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
if (!p)
return NULL;
- memset(p, 0, size);
+ memset(p, 0, PAGE_SIZE);

return p;
}
@@ -526,7 +534,7 @@ pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node)
{
pmd_t *pmd = pmd_offset(pud, addr);
if (pmd_none(*pmd)) {
- void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
+ void *p = vmemmap_alloc_table(node);
if (!p)
return NULL;
pmd_populate_kernel(&init_mm, pmd, p);
@@ -538,7 +546,7 @@ pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
{
pud_t *pud = pud_offset(p4d, addr);
if (pud_none(*pud)) {
- void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
+ void *p = vmemmap_alloc_table(node);
if (!p)
return NULL;
pud_populate(&init_mm, pud, p);
@@ -550,7 +558,7 @@ p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
{
p4d_t *p4d = p4d_offset(pgd, addr);
if (p4d_none(*p4d)) {
- void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
+ void *p = vmemmap_alloc_table(node);
if (!p)
return NULL;
p4d_populate(&init_mm, p4d, p);
@@ -562,7 +570,7 @@ pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
{
pgd_t *pgd = pgd_offset_k(addr);
if (pgd_none(*pgd)) {
- void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
+ void *p = vmemmap_alloc_table(node);
if (!p)
return NULL;
pgd_populate(&init_mm, pgd, p);
--
2.17.1