[PATCH v4 51/66] mm/khugepaged: Use maple tree iterators instead of vma linked list

From: Liam Howlett
Date: Wed Dec 01 2021 - 09:35:56 EST


From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
mm/huge_memory.c | 4 ++--
mm/khugepaged.c | 9 ++++++---
2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index e5483347291c..f0f4ff5239ef 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2270,11 +2270,11 @@ 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 vma_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 0ff7d72cdd1d..8f0633481791 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2083,6 +2083,7 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
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);
@@ -2106,11 +2107,13 @@ static unsigned int khugepaged_scan_mm_slot(unsigned int pages,
vma = NULL;
if (unlikely(!mmap_read_trylock(mm)))
goto breakouterloop_mmap_lock;
- if (likely(!khugepaged_test_exit(mm)))
- vma = find_vma(mm, khugepaged_scan.address);

progress++;
- for (; vma; vma = vma->vm_next) {
+ if (unlikely(khugepaged_test_exit(mm)))
+ goto breakouterloop;
+
+ address = khugepaged_scan.address;
+ mt_for_each(&mm->mm_mt, vma, address, ULONG_MAX) {
unsigned long hstart, hend;

cond_resched();
--
2.30.2