Re: [PATCH 04/16] perf tools: Add a thread stack for synthesizing call chains

From: Namhyung Kim
Date: Fri Oct 24 2014 - 01:41:11 EST


On Thu, 23 Oct 2014 13:45:12 +0300, Adrian Hunter wrote:
> +static void thread_stack__pop(struct thread_stack *ts, u64 ret_addr)
> +{
> + if (!ts->cnt)
> + return;
> +
> + if (ts->stack[ts->cnt - 1].ret_addr == ret_addr) {
> + ts->cnt -= 1;
> + } else {
> + size_t i = ts->cnt - 1;
> +
> + while (i--) {
> + if (ts->stack[i].ret_addr == ret_addr) {
> + ts->cnt = i;
> + return;
> + }
> + }
> + }
> +}

Why not making it a single loop like:

int i;

for (i = ts->cnt - 1; i >= 0; i--) {
if (ts->stack[i].ret_addr == ret_addr) {
ts->cnt = i;
return;
}
}

Thanks,
Namhyung
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/