[PATCH v2 55/70] mm/ksm: Use maple tree iterators instead of vma linked list

From: Liam R. Howlett
Date: Tue Jan 12 2021 - 11:17:25 EST


Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
mm/ksm.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/mm/ksm.c b/mm/ksm.c
index 0960750bb316d..9aa579cef7614 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -975,10 +975,12 @@ static int unmerge_and_remove_all_rmap_items(void)
spin_unlock(&ksm_mmlist_lock);

for (mm_slot = ksm_scan.mm_slot;
- mm_slot != &ksm_mm_head; mm_slot = ksm_scan.mm_slot) {
- mm = mm_slot->mm;
+ mm_slot != &ksm_mm_head; mm_slot = ksm_scan.mm_slot, mm = mm_slot->mm) {
+ MA_STATE(mas, &mm->mm_mt, 0, 0);
+
mmap_read_lock(mm);
- for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ mas_set(&mas, 0);
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (ksm_test_exit(mm))
break;
if (!(vma->vm_flags & VM_MERGEABLE) || !vma->anon_vma)
@@ -2286,13 +2288,14 @@ static struct rmap_item *scan_get_next_rmap_item(struct page **page)
}

mm = slot->mm;
+ MA_STATE(mas, &mm->mm_mt, 0, 0);
+
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) {
+ mas_set(&mas, ksm_scan.address);
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (!(vma->vm_flags & VM_MERGEABLE))
continue;
if (ksm_scan.address < vma->vm_start)
@@ -2330,6 +2333,7 @@ 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;
}
--
2.28.0