[PATCH 07/12] mm: enable MMU_GATHER_RCU_TABLE_FREE for m68k-coldfire
From: Lorenzo Stoakes (ARM)
Date: Tue Sep 01 2026 - 07:12:50 EST
Similar to sun3, the coldfire variant of m68k uses 2-level page tables.
Update its __pte_free_tlb() function to use tlb_remove_ptdesc() in order
that, with CONFIG_MMU_GATHER_RCU_TABLE_FREE, page tables are freed under
RCU.
The page tables occupy a page each and have no odd semantics, so this
change suffices to allow enabling of CONFIG_MMU_GATHER_RCU_TABLE_FREE for
m68k-coldfire, so do so.
This forms part of an overall effort to switch every architecture to this
mode.
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@xxxxxxxxxx>
---
arch/m68k/Kconfig | 2 +-
arch/m68k/include/asm/mcf_pgalloc.h | 5 +----
2 files changed, 2 insertions(+), 5 deletions(-)
diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index e29610fd1240..6b8ec67c86fd 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -36,7 +36,7 @@ config M68K
select HAVE_MOD_ARCH_SPECIFIC
select HAVE_UID16
select MMU_GATHER_NO_RANGE if MMU
- select MMU_GATHER_RCU_TABLE_FREE if MMU && SUN3
+ select MMU_GATHER_RCU_TABLE_FREE if MMU && (SUN3 || COLDFIRE)
select MODULES_USE_ELF_REL
select MODULES_USE_ELF_RELA
select NO_DMA if !MMU && !COLDFIRE
diff --git a/arch/m68k/include/asm/mcf_pgalloc.h b/arch/m68k/include/asm/mcf_pgalloc.h
index fc5454d37da3..b53ff0950db2 100644
--- a/arch/m68k/include/asm/mcf_pgalloc.h
+++ b/arch/m68k/include/asm/mcf_pgalloc.h
@@ -39,10 +39,7 @@ extern inline pmd_t *pmd_alloc_kernel(pgd_t *pgd, unsigned long address)
static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pgtable,
unsigned long address)
{
- struct ptdesc *ptdesc = virt_to_ptdesc(pgtable);
-
- pagetable_dtor(ptdesc);
- pagetable_free(ptdesc);
+ tlb_remove_ptdesc(tlb, virt_to_ptdesc(pgtable));
}
static inline pgtable_t pte_alloc_one(struct mm_struct *mm)
--
2.55.0