[tip:sched/core] sched: Remove the sched_class load_balance methods

tip-bot for Peter Zijlstra
2010-01-21T13:53:12Z

Commit-ID: 3d45fd804a95055ecab5b3eed81f5ab2dbb047a2
Gitweb: http://git.kernel.org/tip/3d45fd804a95055ecab5b3eed81f5ab2dbb047a2
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Thu, 17 Dec 2009 17:12:46 +0100
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 21 Jan 2010 13:40:09 +0100

sched: Remove the sched_class load_balance methods

Take out the sched_class methods for load-balancing.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
include/linux/sched.h | 8 -----
kernel/sched.c | 26 ------------------
kernel/sched_fair.c | 66 ++++++++++++++++++++++++++--------------------
kernel/sched_idletask.c | 21 ---------------
kernel/sched_rt.c | 20 --------------
5 files changed, 37 insertions(+), 104 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index f2f842d..50d685c 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1087,14 +1087,6 @@ struct sched_class {
#ifdef CONFIG_SMP
int (*select_task_rq)(struct task_struct *p, int sd_flag, int flags);

- unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
- struct rq *busiest, unsigned long max_load_move,
- struct sched_domain *sd, enum cpu_idle_type idle,
- int *all_pinned, int *this_best_prio);
-
- int (*move_one_task) (struct rq *this_rq, int this_cpu,
- struct rq *busiest, struct sched_domain *sd,
- enum cpu_idle_type idle);
void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
void (*post_schedule) (struct rq *this_rq);
void (*task_waking) (struct rq *this_rq, struct task_struct *task);
diff --git a/kernel/sched.c b/kernel/sched.c
index 13a2acf..c0be079 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1390,32 +1390,6 @@ static const u32 prio_to_wmult[40] = {
/* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
};

-static void activate_task(struct rq *rq, struct task_struct *p, int wakeup);
-
-/*
- * runqueue iterator, to support SMP load-balancing between different
- * scheduling classes, without having to expose their internal data
- * structures to the load-balancing proper:
- */
-struct rq_iterator {
- void *arg;
- struct task_struct *(*start)(void *);
- struct task_struct *(*next)(void *);
-};
-
-#ifdef CONFIG_SMP
-static unsigned long
-balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
- unsigned long max_load_move, struct sched_domain *sd,
- enum cpu_idle_type idle, int *all_pinned,
- int *this_best_prio, struct rq_iterator *iterator);
-
-static int
-iter_move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
- struct sched_domain *sd, enum cpu_idle_type idle,
- struct rq_iterator *iterator);
-#endif
-
/* Time spent by the tasks of the cpu accounting group executing in ... */
enum cpuacct_stat_index {
CPUACCT_STAT_USER, /* ... user mode */
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 5116b81..faf9a2f 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1851,6 +1851,24 @@ static struct task_struct *load_balance_next_fair(void *arg)
return __load_balance_iterator(cfs_rq, cfs_rq->balance_iterator);
}

+/*
+ * runqueue iterator, to support SMP load-balancing between different
+ * scheduling classes, without having to expose their internal data
+ * structures to the load-balancing proper:
+ */
+struct rq_iterator {
+ void *arg;
+ struct task_struct *(*start)(void *);
+ struct task_struct *(*next)(void *);
+};
+
+static unsigned long
+balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
+ unsigned long max_load_move, struct sched_domain *sd,
+ enum cpu_idle_type idle, int *all_pinned,
+ int *this_best_prio, struct rq_iterator *iterator);
+
+
static unsigned long
__load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move, struct sched_domain *sd,
@@ -1929,8 +1947,20 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
#endif

static int
-move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
- struct sched_domain *sd, enum cpu_idle_type idle)
+iter_move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
+ struct sched_domain *sd, enum cpu_idle_type idle,
+ struct rq_iterator *iterator);
+
+/*
+ * move_one_task tries to move exactly one task from busiest to this_rq, as
+ * part of active balancing operations within "domain".
+ * Returns 1 if successful and 0 otherwise.
+ *
+ * Called with both runqueues locked.
+ */
+static int
+move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
+ struct sched_domain *sd, enum cpu_idle_type idle)
{
struct cfs_rq *busy_cfs_rq;
struct rq_iterator cfs_rq_iterator;
@@ -2094,16 +2124,15 @@ static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
struct sched_domain *sd, enum cpu_idle_type idle,
int *all_pinned)
{
- const struct sched_class *class = sched_class_highest;
- unsigned long total_load_moved = 0;
+ unsigned long total_load_moved = 0, load_moved;
int this_best_prio = this_rq->curr->prio;

do {
- total_load_moved +=
- class->load_balance(this_rq, this_cpu, busiest,
+ load_moved = load_balance_fair(this_rq, this_cpu, busiest,
max_load_move - total_load_moved,
sd, idle, all_pinned, &this_best_prio);
- class = class->next;
+
+ total_load_moved += load_moved;

#ifdef CONFIG_PREEMPT
/*
@@ -2114,7 +2143,7 @@ static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
if (idle == CPU_NEWLY_IDLE && this_rq->nr_running)
break;
#endif
- } while (class && max_load_move > total_load_moved);
+ } while (load_moved && max_load_move > total_load_moved);

return total_load_moved > 0;
}
@@ -2145,25 +2174,6 @@ iter_move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
return 0;
}

-/*
- * move_one_task tries to move exactly one task from busiest to this_rq, as
- * part of active balancing operations within "domain".
- * Returns 1 if successful and 0 otherwise.
- *
- * Called with both runqueues locked.
- */
-static int move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
- struct sched_domain *sd, enum cpu_idle_type idle)
-{
- const struct sched_class *class;
-
- for_each_class(class) {
- if (class->move_one_task(this_rq, this_cpu, busiest, sd, idle))
- return 1;
- }
-
- return 0;
-}
/********** Helpers for find_busiest_group ************************/
/*
* sd_lb_stats - Structure to store the statistics of a sched_domain
@@ -3873,8 +3883,6 @@ static const struct sched_class fair_sched_class = {
#ifdef CONFIG_SMP
.select_task_rq = select_task_rq_fair,

- .load_balance = load_balance_fair,
- .move_one_task = move_one_task_fair,
.rq_online = rq_online_fair,
.rq_offline = rq_offline_fair,

diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c
index 01332bf..a8a6d8a 100644
--- a/kernel/sched_idletask.c
+++ b/kernel/sched_idletask.c
@@ -44,24 +44,6 @@ static void put_prev_task_idle(struct rq *rq, struct task_struct *prev)
{
}

-#ifdef CONFIG_SMP
-static unsigned long
-load_balance_idle(struct rq *this_rq, int this_cpu, struct rq *busiest,
- unsigned long max_load_move,
- struct sched_domain *sd, enum cpu_idle_type idle,
- int *all_pinned, int *this_best_prio)
-{
- return 0;
-}
-
-static int
-move_one_task_idle(struct rq *this_rq, int this_cpu, struct rq *busiest,
- struct sched_domain *sd, enum cpu_idle_type idle)
-{
- return 0;
-}
-#endif
-
static void task_tick_idle(struct rq *rq, struct task_struct *curr, int queued)
{
}
@@ -119,9 +101,6 @@ static const struct sched_class idle_sched_class = {

#ifdef CONFIG_SMP
.select_task_rq = select_task_rq_idle,
-
- .load_balance = load_balance_idle,
- .move_one_task = move_one_task_idle,
#endif

.set_curr_task = set_curr_task_idle,
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 072b3fc..502bb61 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1481,24 +1481,6 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p)
push_rt_tasks(rq);
}

-static unsigned long
-load_balance_rt(struct rq *this_rq, int this_cpu, struct rq *busiest,
- unsigned long max_load_move,
- struct sched_domain *sd, enum cpu_idle_type idle,
- int *all_pinned, int *this_best_prio)
-{
- /* don't touch RT tasks */
- return 0;
-}
-
-static int
-move_one_task_rt(struct rq *this_rq, int this_cpu, struct rq *busiest,
- struct sched_domain *sd, enum cpu_idle_type idle)
-{
- /* don't touch RT tasks */
- return 0;
-}
-
static void set_cpus_allowed_rt(struct task_struct *p,
const struct cpumask *new_mask)
{
@@ -1746,8 +1728,6 @@ static const struct sched_class rt_sched_class = {
#ifdef CONFIG_SMP
.select_task_rq = select_task_rq_rt,

- .load_balance = load_balance_rt,
- .move_one_task = move_one_task_rt,
.set_cpus_allowed = set_cpus_allowed_rt,
.rq_online = rq_online_rt,
.rq_offline = rq_offline_rt,