Re: [v3 1/5] RISC-V: Fix counter restart during overflow for RV32

From: Guo Ren
Date: Mon Jul 11 2022 - 21:45:21 EST


Reviewed-by: Guo Ren <guoren@xxxxxxxxxx>

On Tue, Jul 12, 2022 at 1:46 AM Atish Patra <atishp@xxxxxxxxxxxx> wrote:
>
> Pass the upper half of the initial value of the counter correctly
> for RV32.
>
> Fixes: 4905ec2fb7e6 ("RISC-V: Add sscofpmf extension support")
>
> Signed-off-by: Atish Patra <atishp@xxxxxxxxxxxx>
> ---
> drivers/perf/riscv_pmu_sbi.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
> index dca3537a8dcc..0cb694b794ae 100644
> --- a/drivers/perf/riscv_pmu_sbi.c
> +++ b/drivers/perf/riscv_pmu_sbi.c
> @@ -525,8 +525,13 @@ static inline void pmu_sbi_start_overflow_mask(struct riscv_pmu *pmu,
> hwc = &event->hw;
> max_period = riscv_pmu_ctr_get_width_mask(event);
> init_val = local64_read(&hwc->prev_count) & max_period;
> +#if defined(CONFIG_32BIT)
> + sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1,
> + flag, init_val, init_val >> 32, 0);
> +#else
> sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1,
> flag, init_val, 0, 0);
> +#endif
> }
> ctr_ovf_mask = ctr_ovf_mask >> 1;
> idx++;
> --
> 2.25.1
>


--
Best Regards
Guo Ren