[PATCH v13 53/70] mm/ksm: use vma iterators instead of vma linked list

Liam Howlett
2022-08-22T15:17:07Z

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

Remove the use of the linked list for eventual removal.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
---
mm/ksm.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/mm/ksm.c b/mm/ksm.c
index 2f315c69fa2c..a98bc3beb874 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -981,11 +981,13 @@ static int unmerge_and_remove_all_rmap_items(void)
struct mm_slot, mm_list);
spin_unlock(&ksm_mmlist_lock);

- for (mm_slot = ksm_scan.mm_slot;
- mm_slot != &ksm_mm_head; mm_slot = ksm_scan.mm_slot) {
+ for (mm_slot = ksm_scan.mm_slot; mm_slot != &ksm_mm_head;
+ mm_slot = ksm_scan.mm_slot) {
+ VMA_ITERATOR(vmi, mm_slot->mm, 0);
+
mm = mm_slot->mm;
mmap_read_lock(mm);
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ for_each_vma(vmi, vma) {
if (ksm_test_exit(mm))
break;
if (!(vma->vm_flags & VM_MERGEABLE) || !vma->anon_vma)
@@ -2242,6 +2244,7 @@ static struct rmap_item *scan_get_next_rmap_item(struct page **page)
struct mm_slot *slot;
struct vm_area_struct *vma;
struct rmap_item *rmap_item;
+ struct vma_iterator vmi;
int nid;

if (list_empty(&ksm_mm_head.mm_list))
@@ -2300,13 +2303,13 @@ static struct rmap_item *scan_get_next_rmap_item(struct page **page)
}

mm = slot->mm;
+ vma_iter_init(&vmi, mm, ksm_scan.address);
+
mmap_read_lock(mm);
if (ksm_test_exit(mm))
- vma = NULL;
- else
- vma = find_vma(mm, ksm_scan.address);
+ goto no_vmas;

- for (; vma; vma = vma->vm_next) {
+ for_each_vma(vmi, vma) {
if (!(vma->vm_flags & VM_MERGEABLE))
continue;
if (ksm_scan.address < vma->vm_start)
@@ -2344,6 +2347,7 @@ static struct rmap_item *scan_get_next_rmap_item(struct page **page)
}

if (ksm_test_exit(mm)) {
+no_vmas:
ksm_scan.address = 0;
ksm_scan.rmap_list = &slot->rmap_list;
}
--
2.35.1