lede/target/linux/bcm27xx/patches-6.12/950-0521-mm-vmscan-Maintain-TLB-coherency-in-LRU-code.patch
=?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= d81c03f05e bcm27xx: add 6.12 patches from RPi repo
These patches were generated from:
https://github.com/raspberrypi/linux/commits/rpi-6.12.y
With the following command:
git format-patch -N v6.12.27..HEAD
(HEAD -> 8d3206ee456a5ecdf9ddbfd8e5e231e4f0cd716e)

Exceptions:
- (def)configs patches
- github workflows patches
- applied & reverted patches
- readme patches
- wireless patches

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2025-06-20 17:01:06 +08:00

28 lines
939 B
Diff

From 532fc50f78c39fc56c1256ba1b11ec7d45adf214 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.com>
Date: Thu, 12 Sep 2024 10:06:50 +0100
Subject: [PATCH] mm/vmscan: Maintain TLB coherency in LRU code
As a workaround (and possibly a fix) for CPU spins observed on BCM2837,
use ptep_clear_flush_young instead of ptep_test_and_clear_young inside
lru_gen_look_around in order to expose PTE changes to the MMU. Note that
on architectures that don't require an explicit flush,
ptep_clear_flush_young just calls ptep_test_and_clear_young.
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
---
mm/vmscan.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -4128,7 +4128,7 @@ bool lru_gen_look_around(struct page_vma
if (!folio)
continue;
- if (!ptep_clear_young_notify(vma, addr, pte + i))
+ if (!ptep_clear_flush_young_notify(vma, addr, pte + i))
continue;
young++;