[PATCH 0/7] riscv: ASID-related and UP-related TLB flush enhancements

From: Samuel Holland
Date: Sat Sep 09 2023 - 16:17:34 EST


While reviewing Alexandre Ghiti's "riscv: tlb flush improvements"
series[1], I noticed that the TLB flushing functions mostly end up as
flush_tlb_all() when SMP is disabled. This series resolves that. Along
the way, I realized that we should be using single-ASID flushes wherever
possible, so I implemented that as well. This series is mostly
orthogonal to Alexandre's series, though it does remove the non-ASID
code path from tlbflush.c, which turns out to be required for
flush_tlb_kernel_range().

[1]: https://lore.kernel.org/linux-riscv/20230801085402.1168351-1-alexghiti@xxxxxxxxxxxx/


Samuel Holland (7):
riscv: Apply SiFive CIP-1200 workaround to single-ASID sfence.vma
riscv: mm: Introduce cntx2asid/cntx2version helper macros
riscv: mm: Use a fixed layout for the MM context ID
riscv: mm: Make asid_bits a local variable
riscv: mm: Preserve global TLB entries when switching contexts
riscv: mm: Always flush a single MM context by ASID
riscv: mm: Combine the SMP and non-SMP TLB flushing code

arch/riscv/include/asm/errata_list.h | 12 +++-
arch/riscv/include/asm/mmu.h | 3 +
arch/riscv/include/asm/mmu_context.h | 2 -
arch/riscv/include/asm/tlbflush.h | 41 ++++++-------
arch/riscv/mm/Makefile | 5 +-
arch/riscv/mm/context.c | 26 ++++----
arch/riscv/mm/tlbflush.c | 92 +++++++---------------------
7 files changed, 67 insertions(+), 114 deletions(-)

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2.41.0