+ powerpc-mm-implement-arch_flush_lazy_mmu_mode.patch added to mm-new branch

+ powerpc-mm-implement-arch_flush_lazy_mmu_mode.patch added to mm-new branch

[Andrew Morton]

The patch titled
     Subject: powerpc/mm: implement arch_flush_lazy_mmu_mode()
has been added to the -mm mm-new branch.  Its filename is
     powerpc-mm-implement-arch_flush_lazy_mmu_mode.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/powerpc-mm-implement-arch_flush_lazy_mmu_mode.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: powerpc/mm: implement arch_flush_lazy_mmu_mode()
Date: Mon, 15 Dec 2025 15:03:12 +0000

Upcoming changes to the lazy_mmu API will cause arch_flush_lazy_mmu_mode()
to be called when leaving a nested lazy_mmu section.

Move the relevant logic from arch_leave_lazy_mmu_mode() to
arch_flush_lazy_mmu_mode() and have the former call the latter.  The
radix_enabled() check is required in both as arch_flush_lazy_mmu_mode()
will be called directly from the generic layer in a subsequent patch.

Note: the additional this_cpu_ptr() and radix_enabled() calls on the
arch_leave_lazy_mmu_mode() path will be removed in a subsequent patch.

Link: https://lkml.kernel.org/r/20251215150323.2218608-4-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
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 (Red Hat) <david@kernel.org>
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: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/powerpc/include/asm/book3s/64/tlbflush-hash.h |   15 ++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

--- a/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h~powerpc-mm-implement-arch_flush_lazy_mmu_mode
+++ a/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h
@@ -41,7 +41,7 @@ static inline void arch_enter_lazy_mmu_m
 	batch->active = 1;
 }
 
-static inline void arch_leave_lazy_mmu_mode(void)
+static inline void arch_flush_lazy_mmu_mode(void)
 {
 	struct ppc64_tlb_batch *batch;
 
@@ -51,12 +51,21 @@ static inline void arch_leave_lazy_mmu_m
 
 	if (batch->index)
 		__flush_tlb_pending(batch);
+}
+
+static inline void arch_leave_lazy_mmu_mode(void)
+{
+	struct ppc64_tlb_batch *batch;
+
+	if (radix_enabled())
+		return;
+	batch = this_cpu_ptr(&ppc64_tlb_batch);
+
+	arch_flush_lazy_mmu_mode();
 	batch->active = 0;
 	preempt_enable();
 }
 
-#define arch_flush_lazy_mmu_mode()      do {} while (0)
-
 extern void hash__tlbiel_all(unsigned int action);
 
 extern void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize,
_

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