Re: [PATCH 2/2] sched: make sched_param arugment static variablesin some sched_setscheduler() caller

From: Steven Rostedt
Date: Tue Jul 06 2010 - 18:14:14 EST


On Tue, 2010-07-06 at 09:51 +0900, KOSAKI Motohiro wrote:
> Andrew Morton pointed out almost sched_setscheduler() caller are
> using fixed parameter and it can be converted static. it reduce
> runtume memory waste a bit.

We are replacing runtime waste with permanent waste?

>
> Reported-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>



> --- a/kernel/trace/trace_selftest.c
> +++ b/kernel/trace/trace_selftest.c
> @@ -560,7 +560,7 @@ trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr)
> static int trace_wakeup_test_thread(void *data)
> {
> /* Make this a RT thread, doesn't need to be too high */
> - struct sched_param param = { .sched_priority = 5 };
> + static struct sched_param param = { .sched_priority = 5 };
> struct completion *x = data;
>

This is a thread that runs on boot up to test the sched_wakeup tracer.
Then it is deleted and all memory is reclaimed.

Thus, this patch just took memory that was usable at run time and
removed it permanently.

Please Cc me on all tracing changes.

-- Steve


--
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/