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author | Guo Ren <guoren@linux.alibaba.com> | 2021-06-06 17:20:50 +0200 |
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committer | Palmer Dabbelt <palmerdabbelt@google.com> | 2021-06-30 20:55:39 -0700 |
commit | 3f1e782998cdf6dac037588b99b10b787b00810a (patch) | |
tree | c8b733eb062e7763841a9411b8c4acd9506f0fe6 /arch/riscv/mm/tlbflush.c | |
parent | 70c7605c08c5979e5148085903bfed5feac09406 (diff) | |
download | lwn-3f1e782998cdf6dac037588b99b10b787b00810a.tar.gz lwn-3f1e782998cdf6dac037588b99b10b787b00810a.zip |
riscv: add ASID-based tlbflushing methods
Implement optimized version of the tlb flushing routines for systems
using ASIDs. These are behind the use_asid_allocator static branch to
not affect existing systems not using ASIDs.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
[hch: rebased on top of previous cleanups, use the same algorithm as
the non-ASID based code for local vs global flushes, keep functions
as local as possible]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Diffstat (limited to 'arch/riscv/mm/tlbflush.c')
-rw-r--r-- | arch/riscv/mm/tlbflush.c | 47 |
1 files changed, 40 insertions, 7 deletions
diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c index b458949fa8df..64f8201237c2 100644 --- a/arch/riscv/mm/tlbflush.c +++ b/arch/riscv/mm/tlbflush.c @@ -4,6 +4,24 @@ #include <linux/smp.h> #include <linux/sched.h> #include <asm/sbi.h> +#include <asm/mmu_context.h> + +static inline void local_flush_tlb_all_asid(unsigned long asid) +{ + __asm__ __volatile__ ("sfence.vma x0, %0" + : + : "r" (asid) + : "memory"); +} + +static inline void local_flush_tlb_page_asid(unsigned long addr, + unsigned long asid) +{ + __asm__ __volatile__ ("sfence.vma %0, %1" + : + : "r" (addr), "r" (asid) + : "memory"); +} void flush_tlb_all(void) { @@ -16,21 +34,36 @@ static void __sbi_tlb_flush_range(struct mm_struct *mm, unsigned long start, struct cpumask *cmask = mm_cpumask(mm); struct cpumask hmask; unsigned int cpuid; + bool broadcast; 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; + if (static_branch_unlikely(&use_asid_allocator)) { + unsigned long asid = atomic_long_read(&mm->context.id); - if (cpumask_any_but(cmask, cpuid) >= nr_cpu_ids) { - /* local cpu is the only cpu present in cpumask */ - if (size <= stride) + if (broadcast) { + riscv_cpuid_to_hartid_mask(cmask, &hmask); + sbi_remote_sfence_vma_asid(cpumask_bits(&hmask), + start, size, asid); + } else if (size <= stride) { + local_flush_tlb_page_asid(start, asid); + } else { + local_flush_tlb_all_asid(asid); + } + } else { + if (broadcast) { + riscv_cpuid_to_hartid_mask(cmask, &hmask); + sbi_remote_sfence_vma(cpumask_bits(&hmask), + start, size); + } else if (size <= stride) { local_flush_tlb_page(start); - else + } else { local_flush_tlb_all(); - } else { - riscv_cpuid_to_hartid_mask(cmask, &hmask); - sbi_remote_sfence_vma(cpumask_bits(&hmask), start, size); + } } put_cpu(); |