+ sparc-mm-replace-batch-active-with-is_lazy_mmu_mode_active.patch added to mm-new branch

+ sparc-mm-replace-batch-active-with-is_lazy_mmu_mode_active.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: sparc/mm: replace batch->active with is_lazy_mmu_mode_active()
has been added to the -mm mm-new branch.  Its filename is
     sparc-mm-replace-batch-active-with-is_lazy_mmu_mode_active.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/sparc-mm-replace-batch-active-with-is_lazy_mmu_mode_active.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: Kevin Brodsky <kevin.brodsky@arm.com>
Subject: sparc/mm: replace batch->active with is_lazy_mmu_mode_active()
Date: Mon, 15 Dec 2025 15:03:21 +0000

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.

Link: https://lkml.kernel.org/r/20251215150323.2218608-13-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Hildenbrand <david@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Juegren Gross <jgross@suse.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/sparc/include/asm/tlbflush_64.h |    1 -
 arch/sparc/mm/tlb.c                  |    9 +--------
 2 files changed, 1 insertion(+), 9 deletions(-)

--- a/arch/sparc/include/asm/tlbflush_64.h~sparc-mm-replace-batch-active-with-is_lazy_mmu_mode_active
+++ a/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];
 };
 
--- a/arch/sparc/mm/tlb.c~sparc-mm-replace-batch-active-with-is_lazy_mmu_mode_active
+++ a/arch/sparc/mm/tlb.c
@@ -52,11 +52,7 @@ out:
 
 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_
 		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;
_

Patches currently in -mm which might be from kevin.brodsky@arm.com are

x86-xen-simplify-flush_lazy_mmu.patch
powerpc-mm-implement-arch_flush_lazy_mmu_mode.patch
sparc-mm-implement-arch_flush_lazy_mmu_mode.patch
mm-clarify-lazy_mmu-sleeping-constraints.patch
mm-introduce-config_arch_has_lazy_mmu_mode.patch
mm-introduce-generic-lazy_mmu-helpers.patch
mm-bail-out-of-lazy_mmu_mode_-in-interrupt-context.patch
mm-enable-lazy_mmu-sections-to-nest.patch
arm64-mm-replace-tif_lazy_mmu-with-is_lazy_mmu_mode_active.patch
powerpc-mm-replace-batch-active-with-is_lazy_mmu_mode_active.patch
sparc-mm-replace-batch-active-with-is_lazy_mmu_mode_active.patch
x86-xen-use-lazy_mmu_state-when-context-switching.patch
mm-add-basic-tests-for-lazy_mmu.patch