torvalds/linux
torvalds/linux
2
0
Fork 0
mirror of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-09-04 20:19:47 +08:00
Code

mm: remove arch_flush_tlb_batched_pending() arch helper

Browse Source 
Since commit 4b63491838 ("arm64/mm: Close theoretical race where stale
TLB entry remains valid"), all arches that use tlbbatch for reclaim
(arm64, riscv, x86) implement arch_flush_tlb_batched_pending() with a
flush_tlb_mm().

So let's simplify by removing the unnecessary abstraction and doing the
flush_tlb_mm() directly in flush_tlb_batched_pending().  This effectively
reverts commit db6c1f6f23 ("mm/tlbbatch: introduce
arch_flush_tlb_batched_pending()").

Link: https://lkml.kernel.org/r/20250609103132.447370-1-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Suggested-by: Will Deacon <will@kernel.org>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Ryan Roberts 2025-06-09 11:31:30 +01:00 committed by Andrew Morton
parent 441413d2a9
commit a9e056de66
5 changed files with 1 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
arch/arm64/include/asm/tlbflush.h
View File

@ -322,17 +322,6 @@ static inline bool arch_tlbbatch_should_defer(struct mm_struct *mm)
return true;
}
/*
* If mprotect/munmap/etc occurs during TLB batched flushing, we need to ensure
* all the previously issued TLBIs targeting mm have completed. But since we
* can be executing on a remote CPU, a DSB cannot guarantee this like it can
* for arch_tlbbatch_flush(). Our only option is to flush the entire mm.
*/
static inline void arch_flush_tlb_batched_pending(struct mm_struct *mm)
{
flush_tlb_mm(mm);
}
/*
* To support TLB batched flush for multiple pages unmapping, we only send
* the TLBI for each page in arch_tlbbatch_add_pending() and wait for the

1
arch/riscv/include/asm/tlbflush.h
View File

@ -63,7 +63,6 @@ void flush_pud_tlb_range(struct vm_area_struct *vma, unsigned long start,
bool arch_tlbbatch_should_defer(struct mm_struct *mm);
void arch_tlbbatch_add_pending(struct arch_tlbflush_unmap_batch *batch,
struct mm_struct *mm, unsigned long start, unsigned long end);
void arch_flush_tlb_batched_pending(struct mm_struct *mm);
void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch);
extern unsigned long tlb_flush_all_threshold;

5
arch/riscv/mm/tlbflush.c
View File

@ -234,11 +234,6 @@ void arch_tlbbatch_add_pending(struct arch_tlbflush_unmap_batch *batch,
mmu_notifier_arch_invalidate_secondary_tlbs(mm, start, end);
}
void arch_flush_tlb_batched_pending(struct mm_struct *mm)
{
flush_tlb_mm(mm);
}
void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch)
{
__flush_tlb_range(NULL, &batch->cpumask,

5
arch/x86/include/asm/tlbflush.h
View File

@ -356,11 +356,6 @@ static inline void arch_tlbbatch_add_pending(struct arch_tlbflush_unmap_batch *b
mmu_notifier_arch_invalidate_secondary_tlbs(mm, 0, -1UL);
}
static inline void arch_flush_tlb_batched_pending(struct mm_struct *mm)
{
flush_tlb_mm(mm);
}
extern void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch);
static inline bool pte_flags_need_flush(unsigned long oldflags,

2
mm/rmap.c
View File

@ -746,7 +746,7 @@ void flush_tlb_batched_pending(struct mm_struct *mm)
int flushed = batch >> TLB_FLUSH_BATCH_FLUSHED_SHIFT;
if (pending != flushed) {
arch_flush_tlb_batched_pending(mm);
flush_tlb_mm(mm);
/*
* If the new TLB flushing is pending during flushing, leave
* mm->tlb_flush_batched as is, to avoid losing flushing.