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authorLinus Torvalds <torvalds@linux-foundation.org>2011-05-23 12:53:48 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-05-23 12:53:48 -0700
commit15a3d11b0f2ebdfb3591e411e268aa81998d4723 (patch)
tree56e1d7715653871f015341c7edabd08045f5fc28 /kernel/sched.c
parent1f3a8e093f470ef193b0ca6011d90180331c8b53 (diff)
parentc8b281161dfa4bb5d5be63fb036ce19347b88c63 (diff)
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: Increase SCHED_LOAD_SCALE resolution sched: Introduce SCHED_POWER_SCALE to scale cpu_power calculations sched: Cleanup set_load_weight()
Diffstat (limited to 'kernel/sched.c')
-rw-r--r--kernel/sched.c39
1 files changed, 27 insertions, 12 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 0516af41508..2d12893b8b0 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -293,7 +293,7 @@ static DEFINE_SPINLOCK(task_group_lock);
* limitation from this.)
*/
#define MIN_SHARES 2
-#define MAX_SHARES (1UL << 18)
+#define MAX_SHARES (1UL << (18 + SCHED_LOAD_RESOLUTION))
static int root_task_group_load = ROOT_TASK_GROUP_LOAD;
#endif
@@ -1330,13 +1330,25 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight,
{
u64 tmp;
- tmp = (u64)delta_exec * weight;
+ /*
+ * weight can be less than 2^SCHED_LOAD_RESOLUTION for task group sched
+ * entities since MIN_SHARES = 2. Treat weight as 1 if less than
+ * 2^SCHED_LOAD_RESOLUTION.
+ */
+ if (likely(weight > (1UL << SCHED_LOAD_RESOLUTION)))
+ tmp = (u64)delta_exec * scale_load_down(weight);
+ else
+ tmp = (u64)delta_exec;
if (!lw->inv_weight) {
- if (BITS_PER_LONG > 32 && unlikely(lw->weight >= WMULT_CONST))
+ unsigned long w = scale_load_down(lw->weight);
+
+ if (BITS_PER_LONG > 32 && unlikely(w >= WMULT_CONST))
lw->inv_weight = 1;
+ else if (unlikely(!w))
+ lw->inv_weight = WMULT_CONST;
else
- lw->inv_weight = WMULT_CONST / lw->weight;
+ lw->inv_weight = WMULT_CONST / w;
}
/*
@@ -1778,17 +1790,20 @@ static void dec_nr_running(struct rq *rq)
static void set_load_weight(struct task_struct *p)
{
+ int prio = p->static_prio - MAX_RT_PRIO;
+ struct load_weight *load = &p->se.load;
+
/*
* SCHED_IDLE tasks get minimal weight:
*/
if (p->policy == SCHED_IDLE) {
- p->se.load.weight = WEIGHT_IDLEPRIO;
- p->se.load.inv_weight = WMULT_IDLEPRIO;
+ load->weight = scale_load(WEIGHT_IDLEPRIO);
+ load->inv_weight = WMULT_IDLEPRIO;
return;
}
- p->se.load.weight = prio_to_weight[p->static_prio - MAX_RT_PRIO];
- p->se.load.inv_weight = prio_to_wmult[p->static_prio - MAX_RT_PRIO];
+ load->weight = scale_load(prio_to_weight[prio]);
+ load->inv_weight = prio_to_wmult[prio];
}
static void enqueue_task(struct rq *rq, struct task_struct *p, int flags)
@@ -6527,7 +6542,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group));
printk(KERN_CONT " %s", str);
- if (group->cpu_power != SCHED_LOAD_SCALE) {
+ if (group->cpu_power != SCHED_POWER_SCALE) {
printk(KERN_CONT " (cpu_power = %d)",
group->cpu_power);
}
@@ -7902,7 +7917,7 @@ void __init sched_init(void)
#ifdef CONFIG_SMP
rq->sd = NULL;
rq->rd = NULL;
- rq->cpu_power = SCHED_LOAD_SCALE;
+ rq->cpu_power = SCHED_POWER_SCALE;
rq->post_schedule = 0;
rq->active_balance = 0;
rq->next_balance = jiffies;
@@ -8806,14 +8821,14 @@ cpu_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
static int cpu_shares_write_u64(struct cgroup *cgrp, struct cftype *cftype,
u64 shareval)
{
- return sched_group_set_shares(cgroup_tg(cgrp), shareval);
+ return sched_group_set_shares(cgroup_tg(cgrp), scale_load(shareval));
}
static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
{
struct task_group *tg = cgroup_tg(cgrp);
- return (u64) tg->shares;
+ return (u64) scale_load_down(tg->shares);
}
#endif /* CONFIG_FAIR_GROUP_SCHED */