The patch titled
Subject: mm: pagewalk: move variables to more local scope, tweak loops
has been added to the -mm mm-unstable branch. Its filename is
mm-pagewalk-move-variables-to-more-local-scope-tweak-loops.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-pagewalk-move-variables-to-more-local-scope-tweak-loops.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Rolf Eike Beer <eb@xxxxxxxxx>
Subject: mm: pagewalk: move variables to more local scope, tweak loops
Date: Mon, 22 Aug 2022 15:04:12 +0200
Move some variables to more local scopes to make it obvious that they
don't carry state. Put the end additions into the for loop instructions
to make them easier to read.
Link: https://lkml.kernel.org/r/8155217.NyiUUSuA9g@devpool047
Signed-off-by: Rolf Eike Beer <eb@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/pagewalk.c | 22 +++++++++-------------
1 file changed, 9 insertions(+), 13 deletions(-)
--- a/mm/pagewalk.c~mm-pagewalk-move-variables-to-more-local-scope-tweak-loops
+++ a/mm/pagewalk.c
@@ -25,14 +25,12 @@ static int walk_pte_range_inner(pte_t *p
{
const struct mm_walk_ops *ops = walk->ops;
- for (;;) {
+ for (;; addr += PAGE_SIZE, pte++) {
int err = ops->pte_entry(pte, addr, addr + PAGE_SIZE, walk);
if (err)
return err;
if (addr >= end - PAGE_SIZE)
break;
- addr += PAGE_SIZE;
- pte++;
}
return 0;
}
@@ -42,13 +40,14 @@ static int walk_pte_range(pmd_t *pmd, un
{
pte_t *pte;
int err;
- spinlock_t *ptl;
if (walk->no_vma) {
pte = pte_offset_map(pmd, addr);
err = walk_pte_range_inner(pte, addr, end, walk);
pte_unmap(pte);
} else {
+ spinlock_t *ptl;
+
pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
err = walk_pte_range_inner(pte, addr, end, walk);
pte_unmap_unlock(pte, ptl);
@@ -71,7 +70,7 @@ static int walk_hugepd_range(hugepd_t *p
if (addr & (page_size - 1))
return 0;
- for (;;) {
+ for (;; addr += page_size) {
pte_t *pte;
int err;
@@ -84,7 +83,6 @@ static int walk_hugepd_range(hugepd_t *p
return err;
if (addr >= end - page_size)
break;
- addr += page_size;
}
return 0;
}
@@ -307,14 +305,13 @@ static int walk_hugetlb_range(unsigned l
unsigned long next;
unsigned long hmask = huge_page_mask(h);
unsigned long sz = huge_page_size(h);
- pte_t *pte;
const struct mm_walk_ops *ops = walk->ops;
- do {
+ for (; addr < end; addr = next) {
int err;
+ pte_t *pte = huge_pte_offset(walk->mm, addr & hmask, sz);
next = hugetlb_entry_end(h, addr, end);
- pte = huge_pte_offset(walk->mm, addr & hmask, sz);
if (pte)
err = ops->hugetlb_entry(pte, hmask, addr, next, walk);
@@ -323,7 +320,7 @@ static int walk_hugetlb_range(unsigned l
if (err)
return err;
- } while (addr = next, addr != end);
+ }
return 0;
}
@@ -461,14 +458,13 @@ int walk_page_range(struct mm_struct *mm
do {
int err;
+ walk.vma = vma;
if (!vma) { /* after the last vma */
- walk.vma = NULL;
next = end;
} else if (start < vma->vm_start) { /* outside vma */
walk.vma = NULL;
next = min(end, vma->vm_start);
} else { /* inside vma */
- walk.vma = vma;
next = min(end, vma->vm_end);
vma = find_vma(mm, vma->vm_end);
@@ -595,11 +591,11 @@ int walk_page_mapping(struct address_spa
};
struct vm_area_struct *vma;
pgoff_t vba, vea, cba, cea;
- unsigned long start_addr, end_addr;
lockdep_assert_held(&mapping->i_mmap_rwsem);
vma_interval_tree_foreach(vma, &mapping->i_mmap, first_index,
first_index + nr - 1) {
+ unsigned long start_addr, end_addr;
int err;
/* Clip to the vma */
_
Patches currently in -mm which might be from eb@xxxxxxxxx are
mm-pagewalk-make-error-checks-more-obvious.patch
mm-pagewalk-dont-check-vma-in-walk_page_range_novma.patch
mm-pagewalk-fix-documentation-of-pte-hole-handling.patch
mm-pagewalk-add-api-documentation-for-walk_page_range_novma.patch
mm-pagewalk-allow-walk_page_range_novma-without-mm.patch
mm-pagewalk-move-variables-to-more-local-scope-tweak-loops.patch
