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

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  Re: [PATCH 1/3] timer: Optimize fastpath_timer_check() "George Spelvin" <linux@horizon.com> - 2015-08-26 19:00 +0200
    Re: [PATCH 1/3] timer: Optimize fastpath_timer_check() Jason Low <jason.low2@hp.com> - 2015-08-26 19:40 +0200

#1214039 — Re: [PATCH 1/3] timer: Optimize fastpath_timer_check()

> 	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;
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#1214068

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.

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