[RFC PATCH 08/16] mm/madvise: pass madvise_behavior struct to madvise_dontneed_free()

From: SeongJae Park
Date: Wed Mar 05 2025 - 13:18:09 EST


madvise_dontneed_free() can be optimized to batch tlb flushes by
receiving mmu_gather object that initialized and finished outside, and
doing only gathering of tlb entries that need to be flushed into the
received mmu_gather object. But the function is receiving only one
single behavior integer value. Update it to receive
'struct madvise_behavior' object so that upcoming tlb flushes batching
optimization can pass the mmu_gather object.

Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
mm/madvise.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/mm/madvise.c b/mm/madvise.c
index 6fa7dabe5bad..73a4323197e2 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -890,11 +890,16 @@ static bool madvise_dontneed_free_valid_vma(struct vm_area_struct *vma,
return true;
}

+struct madvise_behavior {
+ int behavior;
+};
+
static long madvise_dontneed_free(struct vm_area_struct *vma,
struct vm_area_struct **prev,
unsigned long start, unsigned long end,
- int behavior)
+ struct madvise_behavior *madv_behavior)
{
+ int behavior = madv_behavior->behavior;
struct mm_struct *mm = vma->vm_mm;

*prev = vma;
@@ -1241,10 +1246,6 @@ static long madvise_guard_remove(struct vm_area_struct *vma,
&guard_remove_walk_ops, NULL);
}

-struct madvise_behavior {
- int behavior;
-};
-
/*
* Apply an madvise behavior to a region of a vma. madvise_update_vma
* will handle splitting a vm area into separate areas, each area with its own
@@ -1276,7 +1277,7 @@ static int madvise_vma_behavior(struct vm_area_struct *vma,
case MADV_FREE:
case MADV_DONTNEED:
case MADV_DONTNEED_LOCKED:
- return madvise_dontneed_free(vma, prev, start, end, behavior);
+ return madvise_dontneed_free(vma, prev, start, end, arg);
case MADV_NORMAL:
new_flags = new_flags & ~VM_RAND_READ & ~VM_SEQ_READ;
break;
--
2.39.5