[PATCH v6 12/14] sparc/mm: replace batch->active with is_lazy_mmu_mode_active()

Kevin Brodsky
2025-12-15T15:04:45Z

A per-CPU batch struct is activated when entering lazy MMU mode; its
lifetime is the same as the lazy MMU section (it is deactivated when
leaving the mode). Preemption is disabled in that interval to ensure
that the per-CPU reference remains valid.

The generic lazy_mmu layer now tracks whether a task is in lazy MMU
mode. We can therefore use the generic helper
is_lazy_mmu_mode_active() to tell whether a batch struct is active
instead of tracking it explicitly.

Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
---
arch/sparc/include/asm/tlbflush_64.h | 1 -
arch/sparc/mm/tlb.c | 9 +--------
2 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/arch/sparc/include/asm/tlbflush_64.h b/arch/sparc/include/asm/tlbflush_64.h
index 4e1036728e2f..6133306ba59a 100644
--- a/arch/sparc/include/asm/tlbflush_64.h
+++ b/arch/sparc/include/asm/tlbflush_64.h
@@ -12,7 +12,6 @@ struct tlb_batch {
unsigned int hugepage_shift;
struct mm_struct *mm;
unsigned long tlb_nr;
- unsigned long active;
unsigned long vaddrs[TLB_BATCH_NR];
};

diff --git a/arch/sparc/mm/tlb.c b/arch/sparc/mm/tlb.c
index 7b5dfcdb1243..3a852071d260 100644
--- a/arch/sparc/mm/tlb.c
+++ b/arch/sparc/mm/tlb.c
@@ -52,11 +52,7 @@ void flush_tlb_pending(void)

void arch_enter_lazy_mmu_mode(void)
{
- struct tlb_batch *tb;
-
preempt_disable();
- tb = this_cpu_ptr(&tlb_batch);
- tb->active = 1;
}

void arch_flush_lazy_mmu_mode(void)
@@ -69,10 +65,7 @@ void arch_flush_lazy_mmu_mode(void)

void arch_leave_lazy_mmu_mode(void)
{
- struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
-
arch_flush_lazy_mmu_mode();
- tb->active = 0;
preempt_enable();
}

@@ -93,7 +86,7 @@ static void tlb_batch_add_one(struct mm_struct *mm, unsigned long vaddr,
nr = 0;
}

- if (!tb->active) {
+ if (!is_lazy_mmu_mode_active()) {
flush_tsb_user_page(mm, vaddr, hugepage_shift);
global_flush_tlb_page(mm, vaddr);
goto out;
--
2.51.2