Re: [ RFC, PATCH 2/5 ] CPU controller - Define group operations

[Jiri Slaby <jirislaby@gmail.com>]

Srivatsa Vaddagiri wrote:
> Define these operations for a task-group:
> 
> 	- create new group
> 	- destroy existing group
> 	- assign bandwidth (quota) for a group
> 	- get bandwidth (quota) of a group
> 
> 
> Signed-off-by : Srivatsa Vaddagiri <vatsa@in.ibm.com>
> 
> 
> 
>  include/linux/sched.h |   12 +++++++
>  kernel/sched.c        |   79 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 91 insertions(+)
> 
> diff -puN kernel/sched.c~cpu_ctlr_grp_ops kernel/sched.c
> --- linux-2.6.18-rc3/kernel/sched.c~cpu_ctlr_grp_ops	2006-08-04 07:58:50.000000000 +0530
> +++ linux-2.6.18-rc3-root/kernel/sched.c	2006-08-04 07:58:50.000000000 +0530
> @@ -7063,3 +7063,82 @@ void set_curr_task(int cpu, struct task_
>  }
>  
>  #endif
> +
> +#ifdef CONFIG_CPUMETER
> +
> +/* Allocate runqueue structures for the new task-group */
> +void *sched_alloc_group(void)
> +{
> +	struct task_grp *tg;
> +	struct task_grp_rq *tgrq;
> +	int i;
> +
> +	tg = kzalloc(sizeof(*tg), GFP_KERNEL);
> +	if (!tg)
> +		return NULL;
> +
> +	tg->ticks = -1;		/* No limit */
> +
> +	for_each_possible_cpu(i) {
> +		tgrq = kzalloc(sizeof(*tgrq), GFP_KERNEL);
> +		if (!tgrq)
> +			goto oom;
> +		tg->rq[i] = tgrq;
> +		task_grp_rq_init(tgrq, tg->ticks);
> +	}
> +
> +	return (void *)tg;

unneeded cast

> +oom:
> +	while (i--)
> +		kfree(tg->rq[i]);
> +
> +	kfree(tg);
> +	return NULL;
> +}
> +
> +/* Deallocate runqueue structures */
> +void sched_dealloc_group(void *grp)
> +{
> +	struct task_grp *tg = (struct task_grp *)grp;

again

> +	int i;
> +
> +	for_each_possible_cpu(i)
> +		kfree(tg->rq[i]);
> +
> +	kfree(tg);
> +}
> +
> +/* Assign quota to this group */
> +void sched_assign_quota(void *grp, int quota)
> +{
> +	struct task_grp *tg = (struct task_grp *)grp;

and one more time

> +	int i;
> +
> +	tg->ticks = (quota * 5 * HZ) / 100;
> +
> +	for_each_possible_cpu(i)
> +		tg->rq[i]->ticks = tg->ticks;
> +
> +}
> +
> +/* Return assigned quota for this group */
> +int sched_get_quota(void *grp)
> +{
> +	struct task_grp *tg = (struct task_grp *)grp;

...

> +	int quota;
> +
> +	quota = (tg->ticks * 100) / (5 * HZ);
> +
> +	return quota;

what about to just
return (tg->ticks * 100) / (5 * HZ);

regards,
-- 
<a href="http://www.fi.muni.cz/~xslaby/">Jiri Slaby</a>
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E