Re: [PATCH v7 03/17] tracing: add MIPS specific trace_clock_local()

David Daney
2009-11-10T17:49:34Z

Wu Zhangjin wrote:
[...]
> + * trace_clock_local(): the simplest and least coherent tracing clock.
> + *
> + * Useful for tracing that does not cross to other CPUs nor
> + * does it go through idle events.
> + */
> +u64 trace_clock_local(void)
> +{
> + unsigned long flags;
> + u64 clock;
> +
> + raw_local_irq_save(flags);
> +
> + clock = mips_timecounter_read();
> +
> + raw_local_irq_restore(flags);
> +
> + return clock;
> +}

Why disable interrupts?

Also you call the new function mips_timecounter_read(). Since
sched_clock() is a weak function, you can override the definition with a
more accurate version when possible. Then you could just directly call
it here, instead of adding the new mips_timecounter_read() that the
'[PATCH v7 02/17] tracing: add mips_timecounter_read() for MIPS' adds.

David Daney