Re: [v2 PATCH] RISC-V: Optimize tlb flush path.

Andreas Schwab
2019-08-20T08:51:15Z

On Aug 20 2019, Atish Patra <Atish.Patra@wdc.com> wrote:

> +
> + cpuid = get_cpu();
> + if (!cmask) {
> + riscv_cpuid_to_hartid_mask(cpu_online_mask, &hmask);
> + goto issue_sfence;
> + }
> +
> +
> + if (cpumask_test_cpu(cpuid, cmask) && cpumask_weight(cmask) ==
> 1) {
> + /* Save trap cost by issuing a local tlb flush here */
> + if ((start == 0 && size == -1) || (size > PAGE_SIZE))
> + local_flush_tlb_all();
> + else if (size == PAGE_SIZE)
> + local_flush_tlb_page(start);
> + goto done;
> + }
> +
> riscv_cpuid_to_hartid_mask(cmask, &hmask);
> +
> +issue_sfence:
> sbi_remote_sfence_vma(hmask.bits, start, size);
> +done:
> + put_cpu();
> }
>
> This is much simpler than what I had done in v2. I will address the if
> condition around size as well.

I still think that this function should be moved out of the header.

Andreas.

--
Andreas Schwab, schwab@linux-m68k.org
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