[PATCH v3 05/16] mm/huge_memory: use helper touch_pmd in huge_pmd_set_accessed

From: Miaohe Lin
Date: Mon Jul 04 2022 - 09:23:01 EST


Use helper touch_pmd to set pmd accessed to simplify the code and improve
the readability. No functional change intended.

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
mm/huge_memory.c | 22 +++++++---------------
1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 30acb3b994cf..f9b6eb3f2215 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1121,15 +1121,15 @@ EXPORT_SYMBOL_GPL(vmf_insert_pfn_pud_prot);
#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */

static void touch_pmd(struct vm_area_struct *vma, unsigned long addr,
- pmd_t *pmd, int flags)
+ pmd_t *pmd, bool write)
{
pmd_t _pmd;

_pmd = pmd_mkyoung(*pmd);
- if (flags & FOLL_WRITE)
+ if (write)
_pmd = pmd_mkdirty(_pmd);
if (pmdp_set_access_flags(vma, addr & HPAGE_PMD_MASK,
- pmd, _pmd, flags & FOLL_WRITE))
+ pmd, _pmd, write))
update_mmu_cache_pmd(vma, addr, pmd);
}

@@ -1162,7 +1162,7 @@ struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
return NULL;

if (flags & FOLL_TOUCH)
- touch_pmd(vma, addr, pmd, flags);
+ touch_pmd(vma, addr, pmd, flags & FOLL_WRITE);

/*
* device mapped pages can only be returned if the
@@ -1399,21 +1399,13 @@ void huge_pud_set_accessed(struct vm_fault *vmf, pud_t orig_pud)

void huge_pmd_set_accessed(struct vm_fault *vmf)
{
- pmd_t entry;
- unsigned long haddr;
bool write = vmf->flags & FAULT_FLAG_WRITE;
- pmd_t orig_pmd = vmf->orig_pmd;

vmf->ptl = pmd_lock(vmf->vma->vm_mm, vmf->pmd);
- if (unlikely(!pmd_same(*vmf->pmd, orig_pmd)))
+ if (unlikely(!pmd_same(*vmf->pmd, vmf->orig_pmd)))
goto unlock;

- entry = pmd_mkyoung(orig_pmd);
- if (write)
- entry = pmd_mkdirty(entry);
- haddr = vmf->address & HPAGE_PMD_MASK;
- if (pmdp_set_access_flags(vmf->vma, haddr, vmf->pmd, entry, write))
- update_mmu_cache_pmd(vmf->vma, vmf->address, vmf->pmd);
+ touch_pmd(vmf->vma, vmf->address, vmf->pmd, write);

unlock:
spin_unlock(vmf->ptl);
@@ -1549,7 +1541,7 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
return ERR_PTR(-ENOMEM);

if (flags & FOLL_TOUCH)
- touch_pmd(vma, addr, pmd, flags);
+ touch_pmd(vma, addr, pmd, flags & FOLL_WRITE);

page += (addr & ~HPAGE_PMD_MASK) >> PAGE_SHIFT;
VM_BUG_ON_PAGE(!PageCompound(page) && !is_zone_device_page(page), page);
--
2.23.0