On Sat, 2016-10-22 at 21:58 +0200, SF Markus Elfring wrote:
> Some data were printed into a sequence by two separate function calls.
> Print the same data by a single function call instead.
[]
> diff --git a/arch/ia64/sn/kernel/sn2/sn2_smp.c b/arch/ia64/sn/kernel/sn2/sn2_smp.c
[]
> @@ -494,12 +494,11 @@ static int sn2_ptc_seq_show(struct seq_file *file, void *data)
> int cpu;
>
> cpu = *(loff_t *) data;
> -
> - if (!cpu) {
> + if (!cpu)
> seq_printf(file,
> - "# cpu ptc_l newrid ptc_flushes nodes_flushed deadlocks lock_nsec shub_nsec shub_nsec_max not_my_mm deadlock2 ipi_fluches ipi_nsec\n");
> - seq_printf(file, "# ptctest %d, flushopt %d\n", sn2_ptctest, sn2_flush_opt);
> - }
> + "# cpu ptc_l newrid ptc_flushes nodes_flushed deadlocks lock_nsec shub_nsec shub_nsec_max not_my_mm deadlock2 ipi_fluches ipi_nsec\n"
> + "# ptctest %d, flushopt %d\n",
> + sn2_ptctest, sn2_flush_opt);
>
> if (cpu < nr_cpu_ids && cpu_online(cpu)) {
> stat = &per_cpu(ptcstats, cpu);
Please think more.
printf has to inspect character by character looking for
a vsprintf % character and 0 termination.
seq_puts does a strlen then memcpy.
Which is faster?
When is it better to call 2 functions?
When does readability matter more than efficiency?
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