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riscv: mm: Combine the SMP and UP TLB flush code

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In SMP configurations, all TLB flushing narrower than flush_tlb_all()
goes through __flush_tlb_range(). Do the same in UP configurations.

This allows UP configurations to take advantage of recent improvements
to the code in tlbflush.c, such as support for huge pages and flushing
multiple-page ranges.

Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Yunhui Cui <cuiyunhui@bytedance.com>
Link: https://lore.kernel.org/r/20240327045035.368512-7-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Samuel Holland 2024-03-26 21:49:47 -07:00 committed by Palmer Dabbelt
parent 9546f00410
commit c6026d35b6
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GPG key ID: 2E1319F35FBB1889
3 changed files with 5 additions and 33 deletions
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2
arch/riscv/Kconfig
View file

@ -60,7 +60,7 @@ config RISCV
select ARCH_USE_MEMTEST
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USES_CFI_TRAPS if CFI_CLANG
select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP && MMU
select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
select ARCH_WANT_FRAME_POINTERS
select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT

31
arch/riscv/include/asm/tlbflush.h
View file

@ -27,12 +27,7 @@ static inline void local_flush_tlb_page(unsigned long addr)
{
ALT_FLUSH_TLB_PAGE(__asm__ __volatile__ ("sfence.vma %0" : : "r" (addr) : "memory"));
}
#else /* CONFIG_MMU */
#define local_flush_tlb_all() do { } while (0)
#define local_flush_tlb_page(addr) do { } while (0)
#endif /* CONFIG_MMU */
#if defined(CONFIG_SMP) && defined(CONFIG_MMU)
void flush_tlb_all(void);
void flush_tlb_mm(struct mm_struct *mm);
void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
@ -54,28 +49,8 @@ void arch_tlbbatch_add_pending(struct arch_tlbflush_unmap_batch *batch,
unsigned long uaddr);
void arch_flush_tlb_batched_pending(struct mm_struct *mm);
void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch);
#else /* CONFIG_SMP && CONFIG_MMU */
#define flush_tlb_all() local_flush_tlb_all()
#define flush_tlb_page(vma, addr) local_flush_tlb_page(addr)
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
local_flush_tlb_all();
}
/* Flush a range of kernel pages */
static inline void flush_tlb_kernel_range(unsigned long start,
unsigned long end)
{
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()
#define local_flush_tlb_kernel_range(start, end) flush_tlb_all()
#endif /* !CONFIG_SMP || !CONFIG_MMU */
#else /* CONFIG_MMU */
#define local_flush_tlb_all() do { } while (0)
#endif /* CONFIG_MMU */
#endif /* _ASM_RISCV_TLBFLUSH_H */

5
arch/riscv/mm/Makefile
View file

@ -13,14 +13,11 @@ endif
KCOV_INSTRUMENT_init.o := n
obj-y += init.o
obj-$(CONFIG_MMU) += extable.o fault.o pageattr.o pgtable.o
obj-$(CONFIG_MMU) += extable.o fault.o pageattr.o pgtable.o tlbflush.o
obj-y += cacheflush.o
obj-y += context.o
obj-y += pmem.o
ifeq ($(CONFIG_MMU),y)
obj-$(CONFIG_SMP) += tlbflush.o
endif
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_PTDUMP_CORE) += ptdump.o
obj-$(CONFIG_KASAN) += kasan_init.o