[patch 3/5] sched: simplify update_cfs_shares parameters

Paul Turner
2011-01-22T05:05:15Z

[-- Attachment #1: sched-clean_update_shares.patch --]
[-- Type: text/plain, Size: 3992 bytes --]

Re-visiting this: Since update_cfs_shares will now only ever re-weight an
entity that is a relative parent of the current entity in enqueue_entity; we
can safely issue the account_entity_enqueue relative to that cfs_rq and avoid
the requirement for special handling of the enqueue case in update_cfs_shares.

Signed-off-by: Paul Turner <pjt@google.com>

---
kernel/sched.c | 2 +-
kernel/sched_fair.c | 22 +++++++++++-----------
2 files changed, 12 insertions(+), 12 deletions(-)

Index: tip3/kernel/sched_fair.c
===================================================================
--- tip3.orig/kernel/sched_fair.c
+++ tip3/kernel/sched_fair.c
@@ -540,7 +540,7 @@ static u64 sched_vslice(struct cfs_rq *c
}

static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update);
-static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta);
+static void update_cfs_shares(struct cfs_rq *cfs_rq);

/*
* Update the current task's runtime statistics. Skip current tasks that
@@ -778,7 +778,7 @@ static void reweight_entity(struct cfs_r
account_entity_enqueue(cfs_rq, se);
}

-static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
+static void update_cfs_shares(struct cfs_rq *cfs_rq)
{
struct task_group *tg;
struct sched_entity *se;
@@ -789,11 +789,11 @@ static void update_cfs_shares(struct cfs
if (!se)
return;

- load = cfs_rq->load.weight + weight_delta;
+ load = cfs_rq->load.weight;

load_weight = atomic_read(&tg->load_weight);
- load_weight -= cfs_rq->load_contribution;
load_weight += load;
+ load_weight -= cfs_rq->load_contribution;

shares = (tg->shares * load);
if (load_weight)
@@ -811,7 +811,7 @@ static void update_entity_shares_tick(st
{
if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) {
update_cfs_load(cfs_rq, 0);
- update_cfs_shares(cfs_rq, 0);
+ update_cfs_shares(cfs_rq);
}
}
#else /* CONFIG_FAIR_GROUP_SCHED */
@@ -819,7 +819,7 @@ static void update_cfs_load(struct cfs_r
{
}

-static inline void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
+static inline void update_cfs_shares(struct cfs_rq *cfs_rq)
{
}

@@ -950,8 +950,8 @@ enqueue_entity(struct cfs_rq *cfs_rq, st
*/
update_curr(cfs_rq);
update_cfs_load(cfs_rq, 0);
- update_cfs_shares(cfs_rq, se->load.weight);
account_entity_enqueue(cfs_rq, se);
+ update_cfs_shares(cfs_rq);

if (flags & ENQUEUE_WAKEUP) {
place_entity(cfs_rq, se, 0);
@@ -1013,7 +1013,7 @@ dequeue_entity(struct cfs_rq *cfs_rq, st
update_cfs_load(cfs_rq, 0);
account_entity_dequeue(cfs_rq, se);
update_min_vruntime(cfs_rq);
- update_cfs_shares(cfs_rq, 0);
+ update_cfs_shares(cfs_rq);

/*
* Normalize the entity after updating the min_vruntime because the
@@ -1254,7 +1254,7 @@ enqueue_task_fair(struct rq *rq, struct
struct cfs_rq *cfs_rq = cfs_rq_of(se);

update_cfs_load(cfs_rq, 0);
- update_cfs_shares(cfs_rq, 0);
+ update_cfs_shares(cfs_rq);
}

hrtick_update(rq);
@@ -1284,7 +1284,7 @@ static void dequeue_task_fair(struct rq
struct cfs_rq *cfs_rq = cfs_rq_of(se);

update_cfs_load(cfs_rq, 0);
- update_cfs_shares(cfs_rq, 0);
+ update_cfs_shares(cfs_rq);
}

hrtick_update(rq);
@@ -2095,7 +2095,7 @@ static int update_shares_cpu(struct task
* We need to update shares after updating tg->load_weight in
* order to adjust the weight of groups with long running tasks.
*/
- update_cfs_shares(cfs_rq, 0);
+ update_cfs_shares(cfs_rq);

raw_spin_unlock_irqrestore(&rq->lock, flags);

Index: tip3/kernel/sched.c
===================================================================
--- tip3.orig/kernel/sched.c
+++ tip3/kernel/sched.c
@@ -8510,7 +8510,7 @@ int sched_group_set_shares(struct task_g
/* Propagate contribution to hierarchy */
raw_spin_lock_irqsave(&rq->lock, flags);
for_each_sched_entity(se)
- update_cfs_shares(group_cfs_rq(se), 0);
+ update_cfs_shares(group_cfs_rq(se));
raw_spin_unlock_irqrestore(&rq->lock, flags);
}