[PATCH v13 52/70] mm/khugepaged: stop using vma linked list

Liam Howlett
2022-08-22T15:11:45Z

From: "Matthew Wilcox (Oracle)" <willy@infradead.org>

Use vma iterator & find_vma() instead of vma linked list.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
mm/huge_memory.c | 4 ++--
mm/khugepaged.c | 11 ++++++++---
2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 83c47a989260..6c5c23ef658a 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2339,11 +2339,11 @@ void vma_adjust_trans_huge(struct vm_area_struct *vma,
split_huge_pmd_if_needed(vma, end);

/*
- * If we're also updating the vma->vm_next->vm_start,
+ * If we're also updating the next vma vm_start,
* check if we need to split it.
*/
if (adjust_next > 0) {
- struct vm_area_struct *next = vma->vm_next;
+ struct vm_area_struct *next = find_vma(vma->vm_mm, vma->vm_end);
unsigned long nstart = next->vm_start;
nstart += adjust_next;
split_huge_pmd_if_needed(next, nstart);
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index d3313b7a8fe5..d8e388106322 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2053,10 +2053,12 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, int *result,
__releases(&khugepaged_mm_lock)
__acquires(&khugepaged_mm_lock)
{
+ struct vma_iterator vmi;
struct mm_slot *mm_slot;
struct mm_struct *mm;
struct vm_area_struct *vma;
int progress = 0;
+ unsigned long address;

VM_BUG_ON(!pages);
lockdep_assert_held(&khugepaged_mm_lock);
@@ -2081,11 +2083,14 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages, int *result,
vma = NULL;
if (unlikely(!mmap_read_trylock(mm)))
goto breakouterloop_mmap_lock;
- if (likely(!hpage_collapse_test_exit(mm)))
- vma = find_vma(mm, khugepaged_scan.address);

progress++;
- for (; vma; vma = vma->vm_next) {
+ if (unlikely(hpage_collapse_test_exit(mm)))
+ goto breakouterloop;
+
+ address = khugepaged_scan.address;
+ vma_iter_init(&vmi, mm, address);
+ for_each_vma(vmi, vma) {
unsigned long hstart, hend;

cond_resched();
--
2.35.1