The quilt patch titled
Subject: mm/madvise: split out populate behavior check logic
has been removed from the -mm tree. Its filename was
mm-madvise-split-out-populate-behavior-check-logic.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: SeongJae Park <sj@xxxxxxxxxx>
Subject: mm/madvise: split out populate behavior check logic
Date: Wed, 12 Mar 2025 09:47:48 -0700
madvise_do_behavior() has a long open-coded 'behavior' check for
MADV_POPULATE_{READ,WRITE}. It adds multiple layers[1] and make the code
arguably take longer time to read. Like is_memory_failure(), split out
the check to a separate function. This is not technically removing the
additional layer but discourage further extending the switch-case. Also
it makes madvise_do_behavior() code shorter and therefore easier to read.
[1] https://lore.kernel.org/bd6d0bf1-c79e-46bd-a810-9791efb9ad73@lucifer.local
Link: https://lkml.kernel.org/r/20250312164750.59215-3-sj@xxxxxxxxxx
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
Reviewed-by: Shakeel Butt <shakeel.butt@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Liam R. Howlett <howlett@xxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/madvise.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
--- a/mm/madvise.c~mm-madvise-split-out-populate-behavior-check-logic
+++ a/mm/madvise.c
@@ -1640,6 +1640,17 @@ static bool is_valid_madvise(unsigned lo
return true;
}
+static bool is_madvise_populate(int behavior)
+{
+ switch (behavior) {
+ case MADV_POPULATE_READ:
+ case MADV_POPULATE_WRITE:
+ return true;
+ default:
+ return false;
+ }
+}
+
static int madvise_do_behavior(struct mm_struct *mm,
unsigned long start, size_t len_in, size_t len, int behavior)
{
@@ -1653,16 +1664,11 @@ static int madvise_do_behavior(struct mm
end = start + len;
blk_start_plug(&plug);
- switch (behavior) {
- case MADV_POPULATE_READ:
- case MADV_POPULATE_WRITE:
+ if (is_madvise_populate(behavior))
error = madvise_populate(mm, start, end, behavior);
- break;
- default:
+ else
error = madvise_walk_vmas(mm, start, end, behavior,
madvise_vma_behavior);
- break;
- }
blk_finish_plug(&plug);
return error;
}
_
Patches currently in -mm which might be from sj@xxxxxxxxxx are
