2022-08-15 13:26:48

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V10 0/4] mm/sparse-vmemmap: Generalise helpers and enable for LoongArch

This series is in order to enable sparse-vmemmap for LoongArch. But
LoongArch cannot use generic helpers directly because MIPS&LoongArch
need to call pgd_init()/pud_init()/pmd_init() when populating page
tables. So we adjust the prototypes of p?d_init() to make generic
helpers can call them, then enable sparse-vmemmap with generic helpers,
and to be further, generalise vmemmap_populate_hugepages() for ARM64,
X86 and LoongArch.

V1 -> V2:
Split ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP to a separate patch.

V2 -> V3:
1, Change the Signed-off-by order of author and committer;
2, Update commit message about the build error on LoongArch.

V3 -> V4:
Change pmd to pmdp for ARM64 for consistency.

V4 -> V5:
Add a detailed comment for no-fallback in the altmap case.

V5 -> V6:
1, Fix build error for NIOS2;
2, Fix build error for allnoconfig;
3, Update comment for no-fallback in the altmap case.

V6 -> V7:
Fix build warnings of "no previous prototype".

V7 -> V8:
Fix build error for MIPS pud_init().

V8 -> V9:
Remove redundant #include to avoid build error with latest upstream
kernel.

V9 -> V10:
Fix build error due to VMEMMAP changes in 6.0-rc1.

Huacai Chen and Feiyang Chen(4):
MIPS&LoongArch&NIOS2: Adjust prototypes of p?d_init().
LoongArch: Add sparse memory vmemmap support.
mm/sparse-vmemmap: Generalise vmemmap_populate_hugepages().
LoongArch: Enable ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP.

Signed-off-by: Huacai Chen <[email protected]>
Signed-off-by: Feiyang Chen <[email protected]>
---
arch/arm64/mm/mmu.c | 53 ++++++--------------
arch/loongarch/Kconfig | 2 +
arch/loongarch/include/asm/pgalloc.h | 13 +----
arch/loongarch/include/asm/pgtable.h | 13 +++--
arch/loongarch/include/asm/sparsemem.h | 8 +++
arch/loongarch/kernel/numa.c | 4 +-
arch/loongarch/mm/init.c | 44 +++++++++++++++-
arch/loongarch/mm/pgtable.c | 23 +++++----
arch/mips/include/asm/pgalloc.h | 8 +--
arch/mips/include/asm/pgtable-64.h | 8 +--
arch/mips/kvm/mmu.c | 3 +-
arch/mips/mm/pgtable-32.c | 10 ++--
arch/mips/mm/pgtable-64.c | 18 ++++---
arch/mips/mm/pgtable.c | 2 +-
arch/x86/mm/init_64.c | 92 ++++++++++++----------------------
include/linux/mm.h | 8 +++
include/linux/page-flags.h | 1 +
mm/sparse-vmemmap.c | 64 +++++++++++++++++++++++
18 files changed, 222 insertions(+), 152 deletions(-)
--
2.27.0


2022-08-15 13:30:35

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V10 4/4] LoongArch: Enable ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP

From: Feiyang Chen <[email protected]>

The feature of minimizing overhead of struct page associated with each
HugeTLB page is implemented on x86_64. However, the infrastructure of
this feature is already there, so just select ARCH_WANT_HUGETLB_PAGE_
OPTIMIZE_VMEMMAP is enough to enable this feature for LoongArch.

To avoid the following build error on LoongArch we should include linux/
static_key.h in page-flags.h.

In file included from ./include/linux/mmzone.h:22,
from ./include/linux/gfp.h:6,
from ./include/linux/mm.h:7,
from arch/loongarch/kernel/asm-offsets.c:9:
./include/linux/page-flags.h:208:1: warning: data definition has no
type or storage class
208 | DECLARE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
| ^~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/page-flags.h:208:1: error: type defaults to 'int' in
declaration of 'DECLARE_STATIC_KEY_MAYBE' [-Werror=implicit-int]
./include/linux/page-flags.h:209:26: warning: parameter names (without
types) in function declaration
209 | hugetlb_optimize_vmemmap_key);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/page-flags.h: In function 'hugetlb_optimize_vmemmap_enabled':
./include/linux/page-flags.h:213:16: error: implicit declaration of
function 'static_branch_maybe' [-Werror=implicit-function-declaration]
213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
| ^~~~~~~~~~~~~~~~~~~
./include/linux/page-flags.h:213:36: error:
'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON' undeclared (first
use in this function); did you mean
'CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP'?
213 | return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
./include/linux/page-flags.h:213:36: note: each undeclared identifier
is reported only once for each function it appears in
./include/linux/page-flags.h:214:37: error:
'hugetlb_optimize_vmemmap_key' undeclared (first use in this
function); did you mean 'hugetlb_optimize_vmemmap_enabled'?
214 | &hugetlb_optimize_vmemmap_key);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
| hugetlb_optimize_vmemmap_enabled

Signed-off-by: Feiyang Chen <[email protected]>
Signed-off-by: Huacai Chen <[email protected]>
---
arch/loongarch/Kconfig | 1 +
include/linux/page-flags.h | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 15e6aca2c930..be04968fe403 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -51,6 +51,7 @@ config LOONGARCH
select ARCH_USE_CMPXCHG_LOCKREF
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
+ select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
select ARCH_WANTS_NO_INSTR
select BUILDTIME_TABLE_SORT
select COMMON_CLK
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 465ff35a8c00..8f49a1b8658a 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -9,6 +9,7 @@
#include <linux/types.h>
#include <linux/bug.h>
#include <linux/mmdebug.h>
+#include <linux/static_key.h>
#ifndef __GENERATING_BOUNDS_H
#include <linux/mm_types.h>
#include <generated/bounds.h>
--
2.31.1

2022-08-15 13:30:46

by Huacai Chen

[permalink] [raw]
Subject: [PATCH V10 2/4] LoongArch: Add sparse memory vmemmap support

From: Feiyang Chen <[email protected]>

Add sparse memory vmemmap support for LoongArch. SPARSEMEM_VMEMMAP
uses a virtually mapped memmap to optimise pfn_to_page and page_to_pfn
operations. This is the most efficient option when sufficient kernel
resources are available.

Signed-off-by: Min Zhou <[email protected]>
Signed-off-by: Feiyang Chen <[email protected]>
Signed-off-by: Huacai Chen <[email protected]>
---
arch/loongarch/Kconfig | 1 +
arch/loongarch/include/asm/pgtable.h | 7 ++-
arch/loongarch/include/asm/sparsemem.h | 6 +++
arch/loongarch/mm/init.c | 73 +++++++++++++++++++++++++-
include/linux/mm.h | 2 +
mm/sparse-vmemmap.c | 10 ++++
6 files changed, 97 insertions(+), 2 deletions(-)

diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 4abc9a28aba4..15e6aca2c930 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -419,6 +419,7 @@ config ARCH_FLATMEM_ENABLE

config ARCH_SPARSEMEM_ENABLE
def_bool y
+ select SPARSEMEM_VMEMMAP_ENABLE
help
Say Y to support efficient handling of sparse physical memory,
for architectures which are either NUMA (Non-Uniform Memory Access)
diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
index 700ce735c101..fcab8c89b56b 100644
--- a/arch/loongarch/include/asm/pgtable.h
+++ b/arch/loongarch/include/asm/pgtable.h
@@ -11,6 +11,7 @@

#include <linux/compiler.h>
#include <asm/addrspace.h>
+#include <asm/page.h>
#include <asm/pgtable-bits.h>

#if CONFIG_PGTABLE_LEVELS == 2
@@ -60,6 +61,7 @@
#include <linux/mmzone.h>
#include <asm/fixmap.h>
#include <asm/io.h>
+#include <asm/sparsemem.h>

struct mm_struct;
struct vm_area_struct;
@@ -87,7 +89,10 @@ extern unsigned long zero_page_mask;
#define VMALLOC_START MODULES_END
#define VMALLOC_END \
(vm_map_base + \
- min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, (1UL << cpu_vabits)) - PMD_SIZE)
+ min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, (1UL << cpu_vabits)) - PMD_SIZE - VMEMMAP_SIZE)
+
+#define vmemmap ((struct page *)((VMALLOC_END + PMD_SIZE) & PMD_MASK))
+#define VMEMMAP_END ((unsigned long)vmemmap + VMEMMAP_SIZE - 1)

#define pte_ERROR(e) \
pr_err("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
diff --git a/arch/loongarch/include/asm/sparsemem.h b/arch/loongarch/include/asm/sparsemem.h
index 3d18cdf1b069..ee55cdf933c6 100644
--- a/arch/loongarch/include/asm/sparsemem.h
+++ b/arch/loongarch/include/asm/sparsemem.h
@@ -11,6 +11,12 @@
#define SECTION_SIZE_BITS 29 /* 2^29 = Largest Huge Page Size */
#define MAX_PHYSMEM_BITS 48

+#ifndef CONFIG_SPARSEMEM_VMEMMAP
+#define VMEMMAP_SIZE 0
+#else
+#define VMEMMAP_SIZE (sizeof(struct page) * (1UL << (cpu_pabits + 1 - PAGE_SHIFT)))
+#endif
+
#endif /* CONFIG_SPARSEMEM */

#ifdef CONFIG_MEMORY_HOTPLUG
diff --git a/arch/loongarch/mm/init.c b/arch/loongarch/mm/init.c
index 7094a68c9b83..78f71f9bf295 100644
--- a/arch/loongarch/mm/init.c
+++ b/arch/loongarch/mm/init.c
@@ -22,7 +22,7 @@
#include <linux/pfn.h>
#include <linux/hardirq.h>
#include <linux/gfp.h>
-#include <linux/initrd.h>
+#include <linux/hugetlb.h>
#include <linux/mmzone.h>

#include <asm/asm-offsets.h>
@@ -157,6 +157,77 @@ void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
#endif
#endif

+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+static int __meminit vmemmap_populate_hugepages(unsigned long start, unsigned long end,
+ int node, struct vmem_altmap *altmap)
+{
+ unsigned long addr = start;
+ unsigned long next;
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ for (addr = start; addr < end; addr = next) {
+ next = pmd_addr_end(addr, end);
+
+ pgd = vmemmap_pgd_populate(addr, node);
+ if (!pgd)
+ return -ENOMEM;
+ p4d = vmemmap_p4d_populate(pgd, addr, node);
+ if (!p4d)
+ return -ENOMEM;
+ pud = vmemmap_pud_populate(p4d, addr, node);
+ if (!pud)
+ return -ENOMEM;
+
+ pmd = pmd_offset(pud, addr);
+ if (pmd_none(*pmd)) {
+ void *p = NULL;
+
+ p = vmemmap_alloc_block_buf(PMD_SIZE, node, NULL);
+ if (p) {
+ pmd_t entry;
+
+ entry = pfn_pmd(virt_to_pfn(p), PAGE_KERNEL);
+ pmd_val(entry) |= _PAGE_HUGE | _PAGE_HGLOBAL;
+ set_pmd_at(&init_mm, addr, pmd, entry);
+
+ continue;
+ }
+ } else if (pmd_val(*pmd) & _PAGE_HUGE) {
+ vmemmap_verify((pte_t *)pmd, node, addr, next);
+ continue;
+ }
+ if (vmemmap_populate_basepages(addr, next, node, NULL))
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+#if CONFIG_PGTABLE_LEVELS == 2
+int __meminit vmemmap_populate(unsigned long start, unsigned long end,
+ int node, struct vmem_altmap *altmap)
+{
+ return vmemmap_populate_basepages(start, end, node, NULL);
+}
+#else
+int __meminit vmemmap_populate(unsigned long start, unsigned long end,
+ int node, struct vmem_altmap *altmap)
+{
+ return vmemmap_populate_hugepages(start, end, node, NULL);
+}
+#endif
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+void vmemmap_free(unsigned long start, unsigned long end,
+ struct vmem_altmap *altmap)
+{
+}
+#endif
+#endif
+
/*
* Align swapper_pg_dir in to 64K, allows its address to be loaded
* with a single LUI instruction in the TLB handlers. If we used
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3bedc449c14d..4b05c1d007b5 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3146,6 +3146,8 @@ void *sparse_buffer_alloc(unsigned long size);
struct page * __populate_section_memmap(unsigned long pfn,
unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
struct dev_pagemap *pgmap);
+void pmd_init(void *addr);
+void pud_init(void *addr);
pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 46ae542118c0..797b30e9050c 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -196,6 +196,10 @@ pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node)
return pmd;
}

+void __weak __meminit pmd_init(void *addr)
+{
+}
+
pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
{
pud_t *pud = pud_offset(p4d, addr);
@@ -203,11 +207,16 @@ pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node)
void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
if (!p)
return NULL;
+ pmd_init(p);
pud_populate(&init_mm, pud, p);
}
return pud;
}

+void __weak __meminit pud_init(void *addr)
+{
+}
+
p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
{
p4d_t *p4d = p4d_offset(pgd, addr);
@@ -215,6 +224,7 @@ p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node)
void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node);
if (!p)
return NULL;
+ pud_init(p);
p4d_populate(&init_mm, p4d, p);
}
return p4d;
--
2.31.1