lkml.org 
[lkml]   [2018]   [Apr]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/7] sched/core: uclamp: add CPU clamp groups accounting
On Mon, Apr 09, 2018 at 05:56:09PM +0100, Patrick Bellasi wrote:
> +struct uclamp_group {
> + /* Utilization clamp value for tasks on this clamp group */
> + int value;
> + /* Number of RUNNABLE tasks on this clamp group */
> + int tasks;
> +};

> +struct uclamp_cpu {
> + /* Utilization clamp value for a CPU */
> + int value;
> + /* Utilization clamp groups affecting this CPU */
> + struct uclamp_group group[CONFIG_UCLAMP_GROUPS_COUNT + 1];
> +};

> @@ -811,6 +885,11 @@ struct rq {
> unsigned long cpu_capacity;
> unsigned long cpu_capacity_orig;
>
> +#ifdef CONFIG_UCLAMP_TASK
> + /* util_{min,max} clamp values based on CPU's active tasks */
> + struct uclamp_cpu uclamp[UCLAMP_CNT];
> +#endif
> +
> struct callback_head *balance_callback;
>
> unsigned char idle_balance;

So that is:

struct rq {

struct uclamp_cpu {
int value;

/* 4 byte hole */

struct uclamp_group {
int value;
int tasks;
} [COUNT + 1]; // size: COUNT+2 * 8 [bytes]

} [2]; // size: 2 * COUNT+2 * 8 [bytes]

};

Which for the default (4) ends up being 96 bytes, or at least 2 lines.
Do you want some alignment such that we don't span more lines?

Which touch extra on enqueue/dequeue, at least it's only for tasks that
have a clamp set.

\
 
 \ /
  Last update: 2018-04-13 11:31    [W:0.673 / U:0.040 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site