Re: [PATCH 1/3] timer: Optimize fastpath_timer_check()

[Jason Low <jason.low2@hp.com>]

On Wed, 2015-08-26 at 12:57 -0400, George Spelvin wrote:
> > 	if (!task_cputime_zero(&tsk->cputime_expires)) {
> >+		struct task_cputime task_sample;
> >+		cputime_t utime, stime;
> >+
> >+		task_cputime(tsk, &utime, &stime);
> >+		task_sample.utime = utime;
> >+		task_sample.stime = stime;
> >+		task_sample.sum_exec_runtime = tsk->se.sum_exec_runtime;
> 
> Er, task_sample.[us]time are already the correct types.
> Whay are the local variables necessary?  How about:
> 
>  	if (!task_cputime_zero(&tsk->cputime_expires)) {
> +		struct task_cputime task_sample;
> +
> +		task_cputime(tsk, &task_simple.utime, &task_simple.stime);
> +		task_sample.sum_exec_runtime = tsk->se.sum_exec_runtime;

Yes, good point. Now that we're moving the task_cputime() call to after
the task_sample structure is declared, the utime and stime local
variables are not required anymore.