[PATCH v1 16/19] sched: update move_task() and helper functions to use u64 for weights

From: Nikhil Rao
Date: Sun May 01 2011 - 21:22:44 EST


This patch updates move_task() and helper functions to use u64 to handle load
weight related calculations.

Signed-off-by: Nikhil Rao <ncrao@xxxxxxxxxx>
---
kernel/sched_fair.c | 41 +++++++++++++++++++----------------------
1 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 850e41b..813bcf0 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -2099,14 +2099,14 @@ move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
return 0;
}

-static unsigned long
+static u64
balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
- unsigned long max_load_move, struct sched_domain *sd,
+ u64 max_load_move, struct sched_domain *sd,
enum cpu_idle_type idle, int *all_pinned,
int *this_best_prio, struct cfs_rq *busiest_cfs_rq)
{
int loops = 0, pulled = 0;
- long rem_load_move = max_load_move;
+ s64 rem_load_move = max_load_move;
struct task_struct *p, *n;

if (max_load_move == 0)
@@ -2199,13 +2199,12 @@ static void update_shares(int cpu)
rcu_read_unlock();
}

-static unsigned long
+static u64
load_balance_fair(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)
+ u64 max_load_move, struct sched_domain *sd,
+ enum cpu_idle_type idle, int *all_pinned, int *this_best_prio)
{
- long rem_load_move = max_load_move;
+ s64 rem_load_move = max_load_move;
int busiest_cpu = cpu_of(busiest);
struct task_group *tg;

@@ -2214,8 +2213,8 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,

list_for_each_entry_rcu(tg, &task_groups, list) {
struct cfs_rq *busiest_cfs_rq = tg->cfs_rq[busiest_cpu];
- unsigned long busiest_h_load = busiest_cfs_rq->h_load;
- unsigned long busiest_weight = busiest_cfs_rq->load.weight;
+ u64 busiest_h_load = busiest_cfs_rq->h_load;
+ u64 busiest_weight = busiest_cfs_rq->load.weight;
u64 rem_load, moved_load;

/*
@@ -2224,8 +2223,8 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
if (!busiest_cfs_rq->task_weight)
continue;

- rem_load = (u64)rem_load_move * busiest_weight;
- rem_load = div_u64(rem_load, busiest_h_load + 1);
+ rem_load = div64_u64(busiest_weight * rem_load_move,
+ busiest_h_load + 1);

moved_load = balance_tasks(this_rq, this_cpu, busiest,
rem_load, sd, idle, all_pinned, this_best_prio,
@@ -2234,8 +2233,8 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
if (!moved_load)
continue;

- moved_load *= busiest_h_load;
- moved_load = div_u64(moved_load, busiest_weight + 1);
+ moved_load = div64_u64(moved_load * busiest_h_load,
+ busiest_weight + 1);

rem_load_move -= moved_load;
if (rem_load_move < 0)
@@ -2250,11 +2249,10 @@ static inline void update_shares(int cpu)
{
}

-static unsigned long
+static u64
load_balance_fair(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)
+ u64 max_load_move, struct sched_domain *sd,
+ enum cpu_idle_type idle, int *all_pinned, int *this_best_prio)
{
return balance_tasks(this_rq, this_cpu, busiest,
max_load_move, sd, idle, all_pinned,
@@ -2270,11 +2268,10 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
* Called with both runqueues locked.
*/
static int move_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)
+ u64 max_load_move, struct sched_domain *sd,
+ enum cpu_idle_type idle, int *all_pinned)
{
- unsigned long total_load_moved = 0, load_moved;
+ u64 total_load_moved = 0, load_moved;
int this_best_prio = this_rq->curr->prio;

do {
--
1.7.3.1

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