On Mon, Jul 22, 2019 at 01:33:43PM -0400, Rik van Riel wrote:
> Refactor enqueue_entity, dequeue_entity, and update_load_avg, in order
> to split out the things we still want to happen at every level in the
> cgroup hierarchy with a flat runqueue from the things we only need to
> happen once.
>
> No functional changes.
> @@ -3500,7 +3500,7 @@ static void detach_entity_load_avg(struct cfs_rq
> *cfs_rq, struct sched_entity *s
> #define DO_ATTACH 0x4
>
> /* Update task and its cfs_rq load average */
> -static inline void update_load_avg(struct cfs_rq *cfs_rq, struct
> sched_entity *se, int flags)
> +static inline bool update_load_avg(struct cfs_rq *cfs_rq, struct
> sched_entity *se, int flags)
> {
> u64 now = cfs_rq_clock_pelt(cfs_rq);
> int decayed;
> @@ -3529,6 +3529,8 @@ static inline void update_load_avg(struct cfs_rq
> *cfs_rq, struct sched_entity *s
>
> } else if (decayed && (flags & UPDATE_TG))
> update_tg_load_avg(cfs_rq, 0);
> +
> + return decayed;
> }
>
> #ifndef CONFIG_64BIT
> @@ -3745,9 +3747,10 @@ static inline void update_misfit_status(struct
> task_struct *p, struct rq *rq)
> #define SKIP_AGE_LOAD 0x0
> #define DO_ATTACH 0x0
>
> -static inline void update_load_avg(struct cfs_rq *cfs_rq, struct
> sched_entity *se, int not_used1)
> +static inline bool update_load_avg(struct cfs_rq *cfs_rq, struct
> sched_entity *se, int not_used1)
> {
> cfs_rq_util_change(cfs_rq, 0);
> + return false;
> }
>
> static inline void remove_entity_load_avg(struct sched_entity *se) {}
> @@ -3870,6 +3873,24 @@ static inline void check_schedstat_required(void)
> * CPU and an up-to-date min_vruntime on the destination CPU.
> */
>
> +static bool
> +enqueue_entity_groups(struct cfs_rq *cfs_rq, struct sched_entity *se, int
> flags)
> +{
> + /*
> + * When enqueuing a sched_entity, we must:
> + * - Update loads to have both entity and cfs_rq synced with now.
> + * - Add its load to cfs_rq->runnable_avg
> + * - For group_entity, update its weight to reflect the new share of
> + * its group cfs_rq
> + * - Add its new weight to cfs_rq->load.weight
> + */
> + if (!update_load_avg(cfs_rq, se, UPDATE_TG | DO_ATTACH))
> + return false;
> +
> + update_cfs_group(se);
> + return true;
> +}
> +
> static void
> enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
> {
> @@ -3894,16 +3915,6 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct
> sched_entity *se, int flags)
> if (renorm && !curr)
> se->vruntime += cfs_rq->min_vruntime;
>
> - /*
> - * When enqueuing a sched_entity, we must:
> - * - Update loads to have both entity and cfs_rq synced with now.
> - * - Add its load to cfs_rq->runnable_avg
> - * - For group_entity, update its weight to reflect the new share of
> - * its group cfs_rq
> - * - Add its new weight to cfs_rq->load.weight
> - */
> - update_load_avg(cfs_rq, se, UPDATE_TG | DO_ATTACH);
> - update_cfs_group(se);
> enqueue_runnable_load_avg(cfs_rq, se);
> account_entity_enqueue(cfs_rq, se);
>
No functional, but you did make update_cfs_group() conditional. Now that
looks OK, but maybe you can do that part in a separate patch with a
little justification of its own.
