2024-05-22 06:13:43

by Bang Li

[permalink] [raw]
Subject: [PATCH v4 0/3] Add update_mmu_tlb_range() to simplify code

This series of commits mainly adds the update_mmu_tlb_range() to
batch update tlb in an address range and implement update_mmu_tlb()
using update_mmu_tlb_range().

After the commit 19eaf44954df ("mm: thp: support allocation of anonymous
multi-size THP"), We may need to batch update tlb of a certain address
range by calling update_mmu_tlb() in a loop. Using the
update_mmu_tlb_range(), we can simplify the code and possibly reduce the
execution of some unnecessary code in some architectures.

Thanks,
Bang

Changes since v3 [3]:
- Add acked-by from David Hildenbrand (patch #2 and patch #3) - thanks!
- Add reviewed-by from Lance Yang (patch #3) - thanks!
- Move the general architecture update_mmu_tlb_range() from patch #2 to
patch #1 (per David)
- Update patch #2 commit log (per David)

Changes since v2 [2]:
- Use generic architecture to implement update_mmu_tlb() (per Ryan)

Changes since v1 [1]:
- Add __HAVE_ARCH_UPDATE_MMU_TLB_RANGE macro (per Lance Yang)

[1] https://lore.kernel.org/linux-mm/[email protected]/
[2] https://lore.kernel.org/linux-mm/[email protected]/
[3] https://lore.kernel.org/linux-mm/[email protected]/

Bang Li (3):
mm: Add update_mmu_tlb_range()
mm: implement update_mmu_tlb() using update_mmu_tlb_range()
mm: Use update_mmu_tlb_range() to simplify code

arch/loongarch/include/asm/pgtable.h | 4 ++--
arch/mips/include/asm/pgtable.h | 4 ++--
arch/riscv/include/asm/pgtable.h | 4 ++--
arch/xtensa/include/asm/pgtable.h | 6 +++---
arch/xtensa/mm/tlb.c | 6 +++---
include/linux/pgtable.h | 11 ++++++++---
mm/memory.c | 4 +---
7 files changed, 21 insertions(+), 18 deletions(-)

--
2.19.1.6.gb485710b



2024-05-22 06:13:44

by Bang Li

[permalink] [raw]
Subject: [PATCH v4 3/3] mm: Use update_mmu_tlb_range() to simplify code

Let us simplify the code by update_mmu_tlb_range().

Reviewed-by: Lance Yang <[email protected]>
Acked-by: David Hildenbrand <[email protected]>
Signed-off-by: Bang Li <[email protected]>
---
mm/memory.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index b5453b86ec4b..1297474546d6 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4416,7 +4416,6 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
vm_fault_t ret = 0;
int nr_pages = 1;
pte_t entry;
- int i;

/* File mapping without ->vm_ops ? */
if (vma->vm_flags & VM_SHARED)
@@ -4486,8 +4485,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
update_mmu_tlb(vma, addr, vmf->pte);
goto release;
} else if (nr_pages > 1 && !pte_range_none(vmf->pte, nr_pages)) {
- for (i = 0; i < nr_pages; i++)
- update_mmu_tlb(vma, addr + PAGE_SIZE * i, vmf->pte + i);
+ update_mmu_tlb_range(vma, addr, vmf->pte, nr_pages);
goto release;
}

--
2.19.1.6.gb485710b


2024-05-22 06:13:56

by Bang Li

[permalink] [raw]
Subject: [PATCH v4 1/3] mm: Add update_mmu_tlb_range()

Added update_mmu_tlb_range(), we can batch update tlb of an
address range.

Signed-off-by: Bang Li <[email protected]>
---
arch/loongarch/include/asm/pgtable.h | 2 ++
arch/mips/include/asm/pgtable.h | 2 ++
arch/riscv/include/asm/pgtable.h | 2 ++
arch/xtensa/include/asm/pgtable.h | 3 +++
arch/xtensa/mm/tlb.c | 6 ++++++
include/linux/pgtable.h | 7 +++++++
6 files changed, 22 insertions(+)

diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
index af3acdf3481a..5ccc2a3a6f7a 100644
--- a/arch/loongarch/include/asm/pgtable.h
+++ b/arch/loongarch/include/asm/pgtable.h
@@ -469,6 +469,8 @@ static inline void update_mmu_cache_range(struct vm_fault *vmf,

#define __HAVE_ARCH_UPDATE_MMU_TLB
#define update_mmu_tlb update_mmu_cache
+#define update_mmu_tlb_range(vma, addr, ptep, nr) \
+ update_mmu_cache_range(NULL, vma, addr, ptep, nr)

static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
unsigned long address, pmd_t *pmdp)
diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index e27a4c83c548..0891ad7d43b6 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -596,6 +596,8 @@ static inline void update_mmu_cache_range(struct vm_fault *vmf,

#define __HAVE_ARCH_UPDATE_MMU_TLB
#define update_mmu_tlb update_mmu_cache
+#define update_mmu_tlb_range(vma, address, ptep, nr) \
+ update_mmu_cache_range(NULL, vma, address, ptep, nr)

static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
unsigned long address, pmd_t *pmdp)
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 55a7c3ec246b..4630815b0253 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -491,6 +491,8 @@ static inline void update_mmu_cache_range(struct vm_fault *vmf,

#define __HAVE_ARCH_UPDATE_MMU_TLB
#define update_mmu_tlb update_mmu_cache
+#define update_mmu_tlb_range(vma, addr, ptep, nr) \
+ update_mmu_cache_range(NULL, vma, addr, ptep, nr)

static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
unsigned long address, pmd_t *pmdp)
diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index 9a7e5e57ee9a..436158bd9030 100644
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -413,6 +413,9 @@ typedef pte_t *pte_addr_t;
void update_mmu_tlb(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep);
#define __HAVE_ARCH_UPDATE_MMU_TLB
+void update_mmu_tlb_range(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep, unsigned int nr);
+#define update_mmu_tlb_range update_mmu_tlb_range

#endif /* !defined (__ASSEMBLY__) */

diff --git a/arch/xtensa/mm/tlb.c b/arch/xtensa/mm/tlb.c
index d8b60d6e50a8..05efba86b870 100644
--- a/arch/xtensa/mm/tlb.c
+++ b/arch/xtensa/mm/tlb.c
@@ -169,6 +169,12 @@ void update_mmu_tlb(struct vm_area_struct *vma,
local_flush_tlb_page(vma, address);
}

+void update_mmu_tlb_range(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep, unsigned int nr)
+{
+ local_flush_tlb_range(vma, address, address + PAGE_SIZE * nr);
+}
+
#ifdef CONFIG_DEBUG_TLB_SANITY

static unsigned get_pte_for_vaddr(unsigned vaddr)
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 18019f037bae..17d1caee39ab 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -729,6 +729,13 @@ static inline void clear_full_ptes(struct mm_struct *mm, unsigned long addr,
* fault. This function updates TLB only, do nothing with cache or others.
* It is the difference with function update_mmu_cache.
*/
+#ifndef update_mmu_tlb_range
+static inline void update_mmu_tlb_range(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep, unsigned int nr)
+{
+}
+#endif
+
#ifndef __HAVE_ARCH_UPDATE_MMU_TLB
static inline void update_mmu_tlb(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep)
--
2.19.1.6.gb485710b


2024-05-22 06:29:19

by Bang Li

[permalink] [raw]
Subject: [PATCH v4 2/3] mm: implement update_mmu_tlb() using update_mmu_tlb_range()

Let's make update_mmu_tlb() simply a generic wrapper around
update_mmu_tlb_range(). Only the latter can now be overridden by the
architecture. We can now remove __HAVE_ARCH_UPDATE_MMU_TLB as well.

Acked-by: David Hildenbrand <[email protected]>
Signed-off-by: Bang Li <[email protected]>
---
arch/loongarch/include/asm/pgtable.h | 2 --
arch/mips/include/asm/pgtable.h | 2 --
arch/riscv/include/asm/pgtable.h | 2 --
arch/xtensa/include/asm/pgtable.h | 3 ---
arch/xtensa/mm/tlb.c | 6 ------
include/linux/pgtable.h | 4 +---
6 files changed, 1 insertion(+), 18 deletions(-)

diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
index 5ccc2a3a6f7a..161dd6e10479 100644
--- a/arch/loongarch/include/asm/pgtable.h
+++ b/arch/loongarch/include/asm/pgtable.h
@@ -467,8 +467,6 @@ static inline void update_mmu_cache_range(struct vm_fault *vmf,
#define update_mmu_cache(vma, addr, ptep) \
update_mmu_cache_range(NULL, vma, addr, ptep, 1)

-#define __HAVE_ARCH_UPDATE_MMU_TLB
-#define update_mmu_tlb update_mmu_cache
#define update_mmu_tlb_range(vma, addr, ptep, nr) \
update_mmu_cache_range(NULL, vma, addr, ptep, nr)

diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index 0891ad7d43b6..c29a551eb0ca 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -594,8 +594,6 @@ static inline void update_mmu_cache_range(struct vm_fault *vmf,
#define update_mmu_cache(vma, address, ptep) \
update_mmu_cache_range(NULL, vma, address, ptep, 1)

-#define __HAVE_ARCH_UPDATE_MMU_TLB
-#define update_mmu_tlb update_mmu_cache
#define update_mmu_tlb_range(vma, address, ptep, nr) \
update_mmu_cache_range(NULL, vma, address, ptep, nr)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 4630815b0253..ddfd6f8cdcb3 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -489,8 +489,6 @@ static inline void update_mmu_cache_range(struct vm_fault *vmf,
#define update_mmu_cache(vma, addr, ptep) \
update_mmu_cache_range(NULL, vma, addr, ptep, 1)

-#define __HAVE_ARCH_UPDATE_MMU_TLB
-#define update_mmu_tlb update_mmu_cache
#define update_mmu_tlb_range(vma, addr, ptep, nr) \
update_mmu_cache_range(NULL, vma, addr, ptep, nr)

diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index 436158bd9030..1647a7cc3fbf 100644
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -410,9 +410,6 @@ void update_mmu_cache_range(struct vm_fault *vmf, struct vm_area_struct *vma,

typedef pte_t *pte_addr_t;

-void update_mmu_tlb(struct vm_area_struct *vma,
- unsigned long address, pte_t *ptep);
-#define __HAVE_ARCH_UPDATE_MMU_TLB
void update_mmu_tlb_range(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep, unsigned int nr);
#define update_mmu_tlb_range update_mmu_tlb_range
diff --git a/arch/xtensa/mm/tlb.c b/arch/xtensa/mm/tlb.c
index 05efba86b870..0a1a815dc796 100644
--- a/arch/xtensa/mm/tlb.c
+++ b/arch/xtensa/mm/tlb.c
@@ -163,12 +163,6 @@ void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
}
}

-void update_mmu_tlb(struct vm_area_struct *vma,
- unsigned long address, pte_t *ptep)
-{
- local_flush_tlb_page(vma, address);
-}
-
void update_mmu_tlb_range(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep, unsigned int nr)
{
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 17d1caee39ab..117b807e3f89 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -736,13 +736,11 @@ static inline void update_mmu_tlb_range(struct vm_area_struct *vma,
}
#endif

-#ifndef __HAVE_ARCH_UPDATE_MMU_TLB
static inline void update_mmu_tlb(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep)
{
+ update_mmu_tlb_range(vma, address, ptep, 1);
}
-#define __HAVE_ARCH_UPDATE_MMU_TLB
-#endif

/*
* Some architectures may be able to avoid expensive synchronization
--
2.19.1.6.gb485710b


2024-05-22 07:36:30

by David Hildenbrand

[permalink] [raw]
Subject: Re: [PATCH v4 1/3] mm: Add update_mmu_tlb_range()

On 22.05.24 08:12, Bang Li wrote:
> Added update_mmu_tlb_range(), we can batch update tlb of an
> address range.
>
> Signed-off-by: Bang Li <[email protected]>
> ---

Acked-by: David Hildenbrand <[email protected]>

--
Cheers,

David / dhildenb