[PATCH v3 44/66] kernel/sched/fair: Use maple tree iterators instead of linked list

From: Liam Howlett
Date: Mon Oct 04 2021 - 21:33:59 EST


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

Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
kernel/sched/fair.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index ff69f245b939..46769907c363 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2720,6 +2720,7 @@ static void task_numa_work(struct callback_head *work)
unsigned long start, end;
unsigned long nr_pte_updates = 0;
long pages, virtpages;
+ MA_STATE(mas, &mm->mm_mt, 0, 0);

SCHED_WARN_ON(p != container_of(work, struct task_struct, numa_work));

@@ -2772,13 +2773,17 @@ static void task_numa_work(struct callback_head *work)

if (!mmap_read_trylock(mm))
return;
- vma = find_vma(mm, start);
+
+ rcu_read_lock();
+ mas_set(&mas, start);
+ vma = mas_find(&mas, ULONG_MAX);
if (!vma) {
reset_ptenuma_scan(p);
start = 0;
- vma = mm->mmap;
+ mas_set(&mas, start);
}
- for (; vma; vma = vma->vm_next) {
+
+ mas_for_each(&mas, vma, ULONG_MAX) {
if (!vma_migratable(vma) || !vma_policy_mof(vma) ||
is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_MIXEDMAP)) {
continue;
@@ -2823,7 +2828,9 @@ static void task_numa_work(struct callback_head *work)
if (pages <= 0 || virtpages <= 0)
goto out;

+ rcu_read_unlock();
cond_resched();
+ rcu_read_lock();
} while (end != vma->vm_end);
}

@@ -2838,6 +2845,7 @@ static void task_numa_work(struct callback_head *work)
mm->numa_scan_offset = start;
else
reset_ptenuma_scan(p);
+ rcu_read_unlock();
mmap_read_unlock(mm);

/*
--
2.30.2