sched: extract walk_tg_tree()
Extract walk_tg_tree() and make it a little more generic so we can use it
in the schedulablity test.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched.c b/kernel/sched.c
index c1bee5f..8c019a1 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1387,6 +1387,51 @@
update_load_sub(&rq->load, load);
}
+#if (defined(CONFIG_SMP) && defined(CONFIG_FAIR_GROUP_SCHED))
+typedef int (*tg_visitor)(struct task_group *, void *);
+
+/*
+ * Iterate the full tree, calling @down when first entering a node and @up when
+ * leaving it for the final time.
+ */
+static int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
+{
+ struct task_group *parent, *child;
+ int ret;
+
+ rcu_read_lock();
+ parent = &root_task_group;
+down:
+ ret = (*down)(parent, data);
+ if (ret)
+ goto out_unlock;
+ list_for_each_entry_rcu(child, &parent->children, siblings) {
+ parent = child;
+ goto down;
+
+up:
+ continue;
+ }
+ ret = (*up)(parent, data);
+ if (ret)
+ goto out_unlock;
+
+ child = parent;
+ parent = parent->parent;
+ if (parent)
+ goto up;
+out_unlock:
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static int tg_nop(struct task_group *tg, void *data)
+{
+ return 0;
+}
+#endif
+
#ifdef CONFIG_SMP
static unsigned long source_load(int cpu, int type);
static unsigned long target_load(int cpu, int type);
@@ -1404,37 +1449,6 @@
#ifdef CONFIG_FAIR_GROUP_SCHED
-typedef void (*tg_visitor)(struct task_group *, int, struct sched_domain *);
-
-/*
- * Iterate the full tree, calling @down when first entering a node and @up when
- * leaving it for the final time.
- */
-static void
-walk_tg_tree(tg_visitor down, tg_visitor up, int cpu, struct sched_domain *sd)
-{
- struct task_group *parent, *child;
-
- rcu_read_lock();
- parent = &root_task_group;
-down:
- (*down)(parent, cpu, sd);
- list_for_each_entry_rcu(child, &parent->children, siblings) {
- parent = child;
- goto down;
-
-up:
- continue;
- }
- (*up)(parent, cpu, sd);
-
- child = parent;
- parent = parent->parent;
- if (parent)
- goto up;
- rcu_read_unlock();
-}
-
static void __set_se_shares(struct sched_entity *se, unsigned long shares);
/*
@@ -1493,11 +1507,11 @@
* This needs to be done in a bottom-up fashion because the rq weight of a
* parent group depends on the shares of its child groups.
*/
-static void
-tg_shares_up(struct task_group *tg, int cpu, struct sched_domain *sd)
+static int tg_shares_up(struct task_group *tg, void *data)
{
unsigned long rq_weight = 0;
unsigned long shares = 0;
+ struct sched_domain *sd = data;
int i;
for_each_cpu_mask(i, sd->span) {
@@ -1522,6 +1536,8 @@
__update_group_shares_cpu(tg, i, shares, rq_weight);
spin_unlock_irqrestore(&rq->lock, flags);
}
+
+ return 0;
}
/*
@@ -1529,10 +1545,10 @@
* This needs to be done in a top-down fashion because the load of a child
* group is a fraction of its parents load.
*/
-static void
-tg_load_down(struct task_group *tg, int cpu, struct sched_domain *sd)
+static int tg_load_down(struct task_group *tg, void *data)
{
unsigned long load;
+ long cpu = (long)data;
if (!tg->parent) {
load = cpu_rq(cpu)->load.weight;
@@ -1543,11 +1559,8 @@
}
tg->cfs_rq[cpu]->h_load = load;
-}
-static void
-tg_nop(struct task_group *tg, int cpu, struct sched_domain *sd)
-{
+ return 0;
}
static void update_shares(struct sched_domain *sd)
@@ -1557,7 +1570,7 @@
if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
sd->last_update = now;
- walk_tg_tree(tg_nop, tg_shares_up, 0, sd);
+ walk_tg_tree(tg_nop, tg_shares_up, sd);
}
}
@@ -1568,9 +1581,9 @@
spin_lock(&rq->lock);
}
-static void update_h_load(int cpu)
+static void update_h_load(long cpu)
{
- walk_tg_tree(tg_load_down, tg_nop, cpu, NULL);
+ walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
}
#else