Re: [PATCH 12/13] riscv/irq: use seq_put_decimal_ull_width() for decimal values

[Alexandre Ghiti]

Hi David,

On 08/11/2024 17:25, David Wang wrote:
> Performance improvement for reading /proc/interrupts on arch riscv
>
> Signed-off-by: David Wang <00107082@xxxxxxx>
> ---
>   arch/riscv/kernel/smp.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
> index c180a647a30e..f1e9c3db094c 100644
> --- a/arch/riscv/kernel/smp.c
> +++ b/arch/riscv/kernel/smp.c
> @@ -226,7 +226,8 @@ void show_ipi_stats(struct seq_file *p, int prec)
>   		seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
>   			   prec >= 4 ? " " : "");
>   		for_each_online_cpu(cpu)
> -			seq_printf(p, "%10u ", irq_desc_kstat_cpu(ipi_desc[i], cpu));
> +			seq_put_decimal_ull_width(p, " ",
> +						  irq_desc_kstat_cpu(ipi_desc[i], cpu), 10);
>   		seq_printf(p, " %s\n", ipi_names[i]);
>   	}
>   }


Very late answer sorry!

I don't have the same output before and after your patch because 
seq_put_decimal_ull_width() second argument is placed *before* the 
number, not after as it was before.

The following diff fixes the issue:

diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c index 
f1e9c3db094c3..4b80ee4e5b2c0 100644 --- a/arch/riscv/kernel/smp.c +++ 
b/arch/riscv/kernel/smp.c @@ -225,9 +225,11 @@ void 
show_ipi_stats(struct seq_file *p, int prec) for (i = 0; i < IPI_MAX; 
i++) { seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i, prec >= 4 ? " " : 
""); - for_each_online_cpu(cpu) - seq_put_decimal_ull_width(p, " ", + 
for_each_online_cpu(cpu) { + seq_put_decimal_ull_width(p, NULL, 
irq_desc_kstat_cpu(ipi_desc[i], cpu), 10); + seq_putc(p, ' '); + } 
seq_printf(p, " %s\n", ipi_names[i]); } }

Will you respin a new version?

Thanks,

Alex