Re: [PATCH v2 5/5] mm: Add update_mmu_tlb_range()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hey Lance,

Thanks for taking time to review!

On 2024/5/7 0:07, Lance Yang wrote:
On Mon, May 6, 2024 at 11:52 PM Bang Li <libang.li@xxxxxxxxxxxx> wrote:

After the commit 19eaf44954df ("mm: thp: support allocation of anonymous
multi-size THP"), it may need to batch update tlb of an address range
through the update_mmu_tlb function. We can simplify this operation by
adding the update_mmu_tlb_range function, which may also reduce the
execution of some unnecessary code in some architectures.

Signed-off-by: Bang Li <libang.li@xxxxxxxxxxxx>
---
  include/linux/pgtable.h | 8 ++++++++
  mm/memory.c             | 4 +---
  2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 18019f037bae..869bfe6054f1 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -737,6 +737,14 @@ static inline void update_mmu_tlb(struct vm_area_struct *vma,
  #define __HAVE_ARCH_UPDATE_MMU_TLB
  #endif

+#ifndef __HAVE_ARCH_UPDATE_MMU_TLB_RANGE

IIRC, the contemporary practice is to define a macro with the same name
as the function if it is being overridden.

The macro __HAVE_ARCH_UPDATE_MMU_TLB_RANGE defined here is aligned with
the macro __HAVE_ARCH_UPDATE_MMU_TLB corresponding to the update_mmu_tlb
function. IMO, it should be better to use my method in this case.

Thanks,
Bang


Thanks,
Lance

+static inline void update_mmu_tlb_range(struct vm_area_struct *vma,
+                               unsigned long address, pte_t *ptep, unsigned int nr)
+{
+}
+#define __HAVE_ARCH_UPDATE_MMU_TLB_RANGE
+#endif
+
  /*
   * Some architectures may be able to avoid expensive synchronization
   * primitives when modifications are made to PTE's which are already
diff --git a/mm/memory.c b/mm/memory.c
index eea6e4984eae..2d53e29cf76e 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4421,7 +4421,6 @@ 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)
@@ -4491,8 +4490,7 @@ 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





[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux