6.6-stable review patch. If anyone has any objections, please let me know.
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From: Alexandre Ghiti alexghiti@rivosinc.com
[ Upstream commit 5e22bfd520ea8740e9a20314d2a890baf304c9d2 ]
This function used to simply flush the whole tlb of all harts, be more subtile and try to only flush the range.
The problem is that we can only use PAGE_SIZE as stride since we don't know the size of the underlying mapping and then this function will be improved only if the size of the region to flush is < threshold * PAGE_SIZE.
Signed-off-by: Alexandre Ghiti alexghiti@rivosinc.com Reviewed-by: Andrew Jones ajones@ventanamicro.com Tested-by: Lad Prabhakar prabhakar.mahadev-lad.rj@bp.renesas.com # On RZ/Five SMARC Reviewed-by: Samuel Holland samuel.holland@sifive.com Tested-by: Samuel Holland samuel.holland@sifive.com Link: https://lore.kernel.org/r/20231030133027.19542-5-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Stable-dep-of: d9807d60c145 ("riscv: mm: execute local TLB flush after populating vmemmap") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/include/asm/tlbflush.h | 11 +++++----- arch/riscv/mm/tlbflush.c | 34 ++++++++++++++++++++++--------- 2 files changed, 30 insertions(+), 15 deletions(-)
diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h index 170a49c531c6..8f3418c5f172 100644 --- a/arch/riscv/include/asm/tlbflush.h +++ b/arch/riscv/include/asm/tlbflush.h @@ -40,6 +40,7 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr); void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end); +void flush_tlb_kernel_range(unsigned long start, unsigned long end); #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE void flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start, @@ -56,15 +57,15 @@ static inline void flush_tlb_range(struct vm_area_struct *vma, local_flush_tlb_all(); }
-#define flush_tlb_mm(mm) flush_tlb_all() -#define flush_tlb_mm_range(mm, start, end, page_size) flush_tlb_all() -#endif /* !CONFIG_SMP || !CONFIG_MMU */ - /* Flush a range of kernel pages */ static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end) { - flush_tlb_all(); + local_flush_tlb_all(); }
+#define flush_tlb_mm(mm) flush_tlb_all() +#define flush_tlb_mm_range(mm, start, end, page_size) flush_tlb_all() +#endif /* !CONFIG_SMP || !CONFIG_MMU */ + #endif /* _ASM_RISCV_TLBFLUSH_H */ diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c index 88fa8b18ca22..8723adc884c7 100644 --- a/arch/riscv/mm/tlbflush.c +++ b/arch/riscv/mm/tlbflush.c @@ -96,20 +96,27 @@ static void __flush_tlb_range(struct mm_struct *mm, unsigned long start, unsigned long size, unsigned long stride) { struct flush_tlb_range_data ftd; - struct cpumask *cmask = mm_cpumask(mm); + const struct cpumask *cmask; unsigned long asid = FLUSH_TLB_NO_ASID; - unsigned int cpuid; bool broadcast;
- if (cpumask_empty(cmask)) - return; + if (mm) { + unsigned int cpuid; + + cmask = mm_cpumask(mm); + if (cpumask_empty(cmask)) + return;
- cpuid = get_cpu(); - /* check if the tlbflush needs to be sent to other CPUs */ - broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids; + cpuid = get_cpu(); + /* check if the tlbflush needs to be sent to other CPUs */ + broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
- if (static_branch_unlikely(&use_asid_allocator)) - asid = atomic_long_read(&mm->context.id) & asid_mask; + if (static_branch_unlikely(&use_asid_allocator)) + asid = atomic_long_read(&mm->context.id) & asid_mask; + } else { + cmask = cpu_online_mask; + broadcast = true; + }
if (broadcast) { if (riscv_use_ipi_for_rfence()) { @@ -127,7 +134,8 @@ static void __flush_tlb_range(struct mm_struct *mm, unsigned long start, local_flush_tlb_range_asid(start, size, stride, asid); }
- put_cpu(); + if (mm) + put_cpu(); }
void flush_tlb_mm(struct mm_struct *mm) @@ -152,6 +160,12 @@ void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, { __flush_tlb_range(vma->vm_mm, start, end - start, PAGE_SIZE); } + +void flush_tlb_kernel_range(unsigned long start, unsigned long end) +{ + __flush_tlb_range(NULL, start, end - start, PAGE_SIZE); +} + #ifdef CONFIG_TRANSPARENT_HUGEPAGE void flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)