[PATCH 9/9] mm/madvise: remove !tlb support from madvise_{dontneed,free}_single_vma()

From: SeongJae Park
Date: Mon Mar 10 2025 - 13:25:29 EST


madvise_dontneed_single_vma() and madvise_free_single_vma() support both
batched tlb flushes and unbatched tlb flushes use cases depending on
received tlb parameter's value. The supports were for safe and fine
transition of the usages from the unbatched flushes to the batched ones.
Now the transition is done, and therefore there is no real unbatched tlb
flushes use case. Remove the code for supporting the no more being used
cases.

Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
mm/madvise.c | 19 ++-----------------
1 file changed, 2 insertions(+), 17 deletions(-)

diff --git a/mm/madvise.c b/mm/madvise.c
index d5f4ce3041a4..25af0a24c00b 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -795,18 +795,11 @@ static const struct mm_walk_ops madvise_free_walk_ops = {
};

static int madvise_free_single_vma(
- struct mmu_gather *caller_tlb, struct vm_area_struct *vma,
+ struct mmu_gather *tlb, struct vm_area_struct *vma,
unsigned long start_addr, unsigned long end_addr)
{
struct mm_struct *mm = vma->vm_mm;
struct mmu_notifier_range range;
- struct mmu_gather self_tlb;
- struct mmu_gather *tlb;
-
- if (caller_tlb)
- tlb = caller_tlb;
- else
- tlb = &self_tlb;

/* MADV_FREE works for only anon vma at the moment */
if (!vma_is_anonymous(vma))
@@ -822,8 +815,6 @@ static int madvise_free_single_vma(
range.start, range.end);

lru_add_drain();
- if (!caller_tlb)
- tlb_gather_mmu(tlb, mm);
update_hiwater_rss(mm);

mmu_notifier_invalidate_range_start(&range);
@@ -832,9 +823,6 @@ static int madvise_free_single_vma(
&madvise_free_walk_ops, tlb);
tlb_end_vma(tlb, vma);
mmu_notifier_invalidate_range_end(&range);
- if (!caller_tlb)
- tlb_finish_mmu(tlb);
-
return 0;
}

@@ -866,10 +854,7 @@ static long madvise_dontneed_single_vma(struct mmu_gather *tlb,
.even_cows = true,
};

- if (!tlb)
- zap_page_range_single(vma, start, end - start, &details);
- else
- unmap_vma_single(tlb, vma, start, end - start, &details);
+ unmap_vma_single(tlb, vma, start, end - start, &details);
return 0;
}

--
2.39.5