sched: fix sched_domain aggregation
Keeping the aggregate on the first cpu of the sched domain has two problems:
- it could collide between different sched domains on different cpus
- it could slow things down because of the remote accesses
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched.c b/kernel/sched.c
index 7d282c5..160d3c2 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1480,12 +1480,12 @@
*/
static inline struct aggregate_struct *
-aggregate(struct task_group *tg, struct sched_domain *sd)
+aggregate(struct task_group *tg, int cpu)
{
- return &tg->cfs_rq[sd->first_cpu]->aggregate;
+ return &tg->cfs_rq[cpu]->aggregate;
}
-typedef void (*aggregate_func)(struct task_group *, struct sched_domain *);
+typedef void (*aggregate_func)(struct task_group *, int, struct sched_domain *);
/*
* Iterate the full tree, calling @down when first entering a node and @up when
@@ -1493,14 +1493,14 @@
*/
static
void aggregate_walk_tree(aggregate_func down, aggregate_func up,
- struct sched_domain *sd)
+ int cpu, struct sched_domain *sd)
{
struct task_group *parent, *child;
rcu_read_lock();
parent = &root_task_group;
down:
- (*down)(parent, sd);
+ (*down)(parent, cpu, sd);
list_for_each_entry_rcu(child, &parent->children, siblings) {
parent = child;
goto down;
@@ -1508,7 +1508,7 @@
up:
continue;
}
- (*up)(parent, sd);
+ (*up)(parent, cpu, sd);
child = parent;
parent = parent->parent;
@@ -1520,8 +1520,8 @@
/*
* Calculate the aggregate runqueue weight.
*/
-static
-void aggregate_group_weight(struct task_group *tg, struct sched_domain *sd)
+static void
+aggregate_group_weight(struct task_group *tg, int cpu, struct sched_domain *sd)
{
unsigned long rq_weight = 0;
unsigned long task_weight = 0;
@@ -1532,15 +1532,15 @@
task_weight += tg->cfs_rq[i]->task_weight;
}
- aggregate(tg, sd)->rq_weight = rq_weight;
- aggregate(tg, sd)->task_weight = task_weight;
+ aggregate(tg, cpu)->rq_weight = rq_weight;
+ aggregate(tg, cpu)->task_weight = task_weight;
}
/*
* Compute the weight of this group on the given cpus.
*/
-static
-void aggregate_group_shares(struct task_group *tg, struct sched_domain *sd)
+static void
+aggregate_group_shares(struct task_group *tg, int cpu, struct sched_domain *sd)
{
unsigned long shares = 0;
int i;
@@ -1548,18 +1548,18 @@
for_each_cpu_mask(i, sd->span)
shares += tg->cfs_rq[i]->shares;
- if ((!shares && aggregate(tg, sd)->rq_weight) || shares > tg->shares)
+ if ((!shares && aggregate(tg, cpu)->rq_weight) || shares > tg->shares)
shares = tg->shares;
- aggregate(tg, sd)->shares = shares;
+ aggregate(tg, cpu)->shares = shares;
}
/*
* Compute the load fraction assigned to this group, relies on the aggregate
* weight and this group's parent's load, i.e. top-down.
*/
-static
-void aggregate_group_load(struct task_group *tg, struct sched_domain *sd)
+static void
+aggregate_group_load(struct task_group *tg, int cpu, struct sched_domain *sd)
{
unsigned long load;
@@ -1571,17 +1571,17 @@
load += cpu_rq(i)->load.weight;
} else {
- load = aggregate(tg->parent, sd)->load;
+ load = aggregate(tg->parent, cpu)->load;
/*
* shares is our weight in the parent's rq so
* shares/parent->rq_weight gives our fraction of the load
*/
- load *= aggregate(tg, sd)->shares;
- load /= aggregate(tg->parent, sd)->rq_weight + 1;
+ load *= aggregate(tg, cpu)->shares;
+ load /= aggregate(tg->parent, cpu)->rq_weight + 1;
}
- aggregate(tg, sd)->load = load;
+ aggregate(tg, cpu)->load = load;
}
static void __set_se_shares(struct sched_entity *se, unsigned long shares);
@@ -1590,8 +1590,8 @@
* Calculate and set the cpu's group shares.
*/
static void
-__update_group_shares_cpu(struct task_group *tg, struct sched_domain *sd,
- int tcpu)
+__update_group_shares_cpu(struct task_group *tg, int cpu,
+ struct sched_domain *sd, int tcpu)
{
int boost = 0;
unsigned long shares;
@@ -1618,8 +1618,8 @@
* \Sum rq_weight
*
*/
- shares = aggregate(tg, sd)->shares * rq_weight;
- shares /= aggregate(tg, sd)->rq_weight + 1;
+ shares = aggregate(tg, cpu)->shares * rq_weight;
+ shares /= aggregate(tg, cpu)->rq_weight + 1;
/*
* record the actual number of shares, not the boosted amount.
@@ -1639,15 +1639,15 @@
* task went to.
*/
static void
-__move_group_shares(struct task_group *tg, struct sched_domain *sd,
+__move_group_shares(struct task_group *tg, int cpu, struct sched_domain *sd,
int scpu, int dcpu)
{
unsigned long shares;
shares = tg->cfs_rq[scpu]->shares + tg->cfs_rq[dcpu]->shares;
- __update_group_shares_cpu(tg, sd, scpu);
- __update_group_shares_cpu(tg, sd, dcpu);
+ __update_group_shares_cpu(tg, cpu, sd, scpu);
+ __update_group_shares_cpu(tg, cpu, sd, dcpu);
/*
* ensure we never loose shares due to rounding errors in the
@@ -1663,19 +1663,19 @@
* we need to walk up the tree and change all shares until we hit the root.
*/
static void
-move_group_shares(struct task_group *tg, struct sched_domain *sd,
+move_group_shares(struct task_group *tg, int cpu, struct sched_domain *sd,
int scpu, int dcpu)
{
while (tg) {
- __move_group_shares(tg, sd, scpu, dcpu);
+ __move_group_shares(tg, cpu, sd, scpu, dcpu);
tg = tg->parent;
}
}
-static
-void aggregate_group_set_shares(struct task_group *tg, struct sched_domain *sd)
+static void
+aggregate_group_set_shares(struct task_group *tg, int cpu, struct sched_domain *sd)
{
- unsigned long shares = aggregate(tg, sd)->shares;
+ unsigned long shares = aggregate(tg, cpu)->shares;
int i;
for_each_cpu_mask(i, sd->span) {
@@ -1683,20 +1683,20 @@
unsigned long flags;
spin_lock_irqsave(&rq->lock, flags);
- __update_group_shares_cpu(tg, sd, i);
+ __update_group_shares_cpu(tg, cpu, sd, i);
spin_unlock_irqrestore(&rq->lock, flags);
}
- aggregate_group_shares(tg, sd);
+ aggregate_group_shares(tg, cpu, sd);
/*
* ensure we never loose shares due to rounding errors in the
* above redistribution.
*/
- shares -= aggregate(tg, sd)->shares;
+ shares -= aggregate(tg, cpu)->shares;
if (shares) {
- tg->cfs_rq[sd->first_cpu]->shares += shares;
- aggregate(tg, sd)->shares += shares;
+ tg->cfs_rq[cpu]->shares += shares;
+ aggregate(tg, cpu)->shares += shares;
}
}
@@ -1704,21 +1704,21 @@
* Calculate the accumulative weight and recursive load of each task group
* while walking down the tree.
*/
-static
-void aggregate_get_down(struct task_group *tg, struct sched_domain *sd)
+static void
+aggregate_get_down(struct task_group *tg, int cpu, struct sched_domain *sd)
{
- aggregate_group_weight(tg, sd);
- aggregate_group_shares(tg, sd);
- aggregate_group_load(tg, sd);
+ aggregate_group_weight(tg, cpu, sd);
+ aggregate_group_shares(tg, cpu, sd);
+ aggregate_group_load(tg, cpu, sd);
}
/*
* Rebalance the cpu shares while walking back up the tree.
*/
-static
-void aggregate_get_up(struct task_group *tg, struct sched_domain *sd)
+static void
+aggregate_get_up(struct task_group *tg, int cpu, struct sched_domain *sd)
{
- aggregate_group_set_shares(tg, sd);
+ aggregate_group_set_shares(tg, cpu, sd);
}
static DEFINE_PER_CPU(spinlock_t, aggregate_lock);
@@ -1731,18 +1731,18 @@
spin_lock_init(&per_cpu(aggregate_lock, i));
}
-static int get_aggregate(struct sched_domain *sd)
+static int get_aggregate(int cpu, struct sched_domain *sd)
{
- if (!spin_trylock(&per_cpu(aggregate_lock, sd->first_cpu)))
+ if (!spin_trylock(&per_cpu(aggregate_lock, cpu)))
return 0;
- aggregate_walk_tree(aggregate_get_down, aggregate_get_up, sd);
+ aggregate_walk_tree(aggregate_get_down, aggregate_get_up, cpu, sd);
return 1;
}
-static void put_aggregate(struct sched_domain *sd)
+static void put_aggregate(int cpu, struct sched_domain *sd)
{
- spin_unlock(&per_cpu(aggregate_lock, sd->first_cpu));
+ spin_unlock(&per_cpu(aggregate_lock, cpu));
}
static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
@@ -1756,12 +1756,12 @@
{
}
-static inline int get_aggregate(struct sched_domain *sd)
+static inline int get_aggregate(int cpu, struct sched_domain *sd)
{
return 0;
}
-static inline void put_aggregate(struct sched_domain *sd)
+static inline void put_aggregate(int cpu, struct sched_domain *sd)
{
}
#endif
@@ -3539,7 +3539,7 @@
cpus_setall(*cpus);
- unlock_aggregate = get_aggregate(sd);
+ unlock_aggregate = get_aggregate(this_cpu, sd);
/*
* When power savings policy is enabled for the parent domain, idle
@@ -3678,7 +3678,7 @@
ld_moved = 0;
out:
if (unlock_aggregate)
- put_aggregate(sd);
+ put_aggregate(this_cpu, sd);
return ld_moved;
}
@@ -7292,7 +7292,6 @@
SD_INIT(sd, ALLNODES);
set_domain_attribute(sd, attr);
sd->span = *cpu_map;
- sd->first_cpu = first_cpu(sd->span);
cpu_to_allnodes_group(i, cpu_map, &sd->groups, tmpmask);
p = sd;
sd_allnodes = 1;
@@ -7303,7 +7302,6 @@
SD_INIT(sd, NODE);
set_domain_attribute(sd, attr);
sched_domain_node_span(cpu_to_node(i), &sd->span);
- sd->first_cpu = first_cpu(sd->span);
sd->parent = p;
if (p)
p->child = sd;
@@ -7315,7 +7313,6 @@
SD_INIT(sd, CPU);
set_domain_attribute(sd, attr);
sd->span = *nodemask;
- sd->first_cpu = first_cpu(sd->span);
sd->parent = p;
if (p)
p->child = sd;
@@ -7327,7 +7324,6 @@
SD_INIT(sd, MC);
set_domain_attribute(sd, attr);
sd->span = cpu_coregroup_map(i);
- sd->first_cpu = first_cpu(sd->span);
cpus_and(sd->span, sd->span, *cpu_map);
sd->parent = p;
p->child = sd;
@@ -7340,7 +7336,6 @@
SD_INIT(sd, SIBLING);
set_domain_attribute(sd, attr);
sd->span = per_cpu(cpu_sibling_map, i);
- sd->first_cpu = first_cpu(sd->span);
cpus_and(sd->span, sd->span, *cpu_map);
sd->parent = p;
p->child = sd;
