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sched: Break out cpu_power from the sched_group structure
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In order to prepare for non-unique sched_groups per domain, we need to
carry the cpu_power elsewhere, so put a level of indirection in.

Reported-and-tested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-qkho2byuhe4482fuknss40ad@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Peter Zijlstra authored and Ingo Molnar committed Jul 20, 2011
1 parent e6625fa commit 9c3f75c
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Showing 3 changed files with 58 additions and 34 deletions.
14 changes: 9 additions & 5 deletions include/linux/sched.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -893,16 +893,20 @@ static inline int sd_power_saving_flags(void)
return 0;
}

struct sched_group {
struct sched_group *next; /* Must be a circular list */
atomic_t ref;

struct sched_group_power {
/*
* CPU power of this group, SCHED_LOAD_SCALE being max power for a
* single CPU.
*/
unsigned int cpu_power, cpu_power_orig;
unsigned int power, power_orig;
};

struct sched_group {
struct sched_group *next; /* Must be a circular list */
atomic_t ref;

unsigned int group_weight;
struct sched_group_power *sgp;

/*
* The CPUs this group covers.
Expand Down
32 changes: 26 additions & 6 deletions kernel/sched.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -6557,7 +6557,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
break;
}

if (!group->cpu_power) {
if (!group->sgp->power) {
printk(KERN_CONT "\n");
printk(KERN_ERR "ERROR: domain->cpu_power not "
"set\n");
Expand All @@ -6581,9 +6581,9 @@ 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_POWER_SCALE) {
if (group->sgp->power != SCHED_POWER_SCALE) {
printk(KERN_CONT " (cpu_power = %d)",
group->cpu_power);
group->sgp->power);
}

group = group->next;
Expand Down Expand Up @@ -6777,8 +6777,10 @@ static struct root_domain *alloc_rootdomain(void)
static void free_sched_domain(struct rcu_head *rcu)
{
struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu);
if (atomic_dec_and_test(&sd->groups->ref))
if (atomic_dec_and_test(&sd->groups->ref)) {
kfree(sd->groups->sgp);
kfree(sd->groups);
}
kfree(sd);
}

Expand Down Expand Up @@ -6945,6 +6947,7 @@ int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
struct sd_data {
struct sched_domain **__percpu sd;
struct sched_group **__percpu sg;
struct sched_group_power **__percpu sgp;
};

struct s_data {
Expand Down Expand Up @@ -6981,8 +6984,10 @@ static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg)
if (child)
cpu = cpumask_first(sched_domain_span(child));

if (sg)
if (sg) {
*sg = *per_cpu_ptr(sdd->sg, cpu);
(*sg)->sgp = *per_cpu_ptr(sdd->sgp, cpu);
}

return cpu;
}
Expand Down Expand Up @@ -7020,7 +7025,7 @@ build_sched_groups(struct sched_domain *sd)
continue;

cpumask_clear(sched_group_cpus(sg));
sg->cpu_power = 0;
sg->sgp->power = 0;

for_each_cpu(j, span) {
if (get_group(j, sdd, NULL) != group)
Expand Down Expand Up @@ -7185,6 +7190,7 @@ static void claim_allocations(int cpu, struct sched_domain *sd)
if (cpu == cpumask_first(sched_group_cpus(sg))) {
WARN_ON_ONCE(*per_cpu_ptr(sdd->sg, cpu) != sg);
*per_cpu_ptr(sdd->sg, cpu) = NULL;
*per_cpu_ptr(sdd->sgp, cpu) = NULL;
}
}

Expand Down Expand Up @@ -7234,9 +7240,14 @@ static int __sdt_alloc(const struct cpumask *cpu_map)
if (!sdd->sg)
return -ENOMEM;

sdd->sgp = alloc_percpu(struct sched_group_power *);
if (!sdd->sgp)
return -ENOMEM;

for_each_cpu(j, cpu_map) {
struct sched_domain *sd;
struct sched_group *sg;
struct sched_group_power *sgp;

sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(),
GFP_KERNEL, cpu_to_node(j));
Expand All @@ -7251,6 +7262,13 @@ static int __sdt_alloc(const struct cpumask *cpu_map)
return -ENOMEM;

*per_cpu_ptr(sdd->sg, j) = sg;

sgp = kzalloc_node(sizeof(struct sched_group_power),
GFP_KERNEL, cpu_to_node(j));
if (!sgp)
return -ENOMEM;

*per_cpu_ptr(sdd->sgp, j) = sgp;
}
}

Expand All @@ -7268,9 +7286,11 @@ static void __sdt_free(const struct cpumask *cpu_map)
for_each_cpu(j, cpu_map) {
kfree(*per_cpu_ptr(sdd->sd, j));
kfree(*per_cpu_ptr(sdd->sg, j));
kfree(*per_cpu_ptr(sdd->sgp, j));
}
free_percpu(sdd->sd);
free_percpu(sdd->sg);
free_percpu(sdd->sgp);
}
}

Expand Down
46 changes: 23 additions & 23 deletions kernel/sched_fair.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1585,7 +1585,7 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
}

/* Adjust by relative CPU power of the group */
avg_load = (avg_load * SCHED_POWER_SCALE) / group->cpu_power;
avg_load = (avg_load * SCHED_POWER_SCALE) / group->sgp->power;

if (local_group) {
this_load = avg_load;
Expand Down Expand Up @@ -2631,7 +2631,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
power >>= SCHED_POWER_SHIFT;
}

sdg->cpu_power_orig = power;
sdg->sgp->power_orig = power;

if (sched_feat(ARCH_POWER))
power *= arch_scale_freq_power(sd, cpu);
Expand All @@ -2647,7 +2647,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
power = 1;

cpu_rq(cpu)->cpu_power = power;
sdg->cpu_power = power;
sdg->sgp->power = power;
}

static void update_group_power(struct sched_domain *sd, int cpu)
Expand All @@ -2665,11 +2665,11 @@ static void update_group_power(struct sched_domain *sd, int cpu)

group = child->groups;
do {
power += group->cpu_power;
power += group->sgp->power;
group = group->next;
} while (group != child->groups);

sdg->cpu_power = power;
sdg->sgp->power = power;
}

/*
Expand All @@ -2691,7 +2691,7 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
/*
* If ~90% of the cpu_power is still there, we're good.
*/
if (group->cpu_power * 32 > group->cpu_power_orig * 29)
if (group->sgp->power * 32 > group->sgp->power_orig * 29)
return 1;

return 0;
Expand Down Expand Up @@ -2771,7 +2771,7 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
}

/* Adjust by relative CPU power of the group */
sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->cpu_power;
sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->sgp->power;

/*
* Consider the group unbalanced when the imbalance is larger
Expand All @@ -2788,7 +2788,7 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
if ((max_cpu_load - min_cpu_load) >= avg_load_per_task && max_nr_running > 1)
sgs->group_imb = 1;

sgs->group_capacity = DIV_ROUND_CLOSEST(group->cpu_power,
sgs->group_capacity = DIV_ROUND_CLOSEST(group->sgp->power,
SCHED_POWER_SCALE);
if (!sgs->group_capacity)
sgs->group_capacity = fix_small_capacity(sd, group);
Expand Down Expand Up @@ -2877,7 +2877,7 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
return;

sds->total_load += sgs.group_load;
sds->total_pwr += sg->cpu_power;
sds->total_pwr += sg->sgp->power;

/*
* In case the child domain prefers tasks go to siblings
Expand Down Expand Up @@ -2962,7 +2962,7 @@ static int check_asym_packing(struct sched_domain *sd,
if (this_cpu > busiest_cpu)
return 0;

*imbalance = DIV_ROUND_CLOSEST(sds->max_load * sds->busiest->cpu_power,
*imbalance = DIV_ROUND_CLOSEST(sds->max_load * sds->busiest->sgp->power,
SCHED_POWER_SCALE);
return 1;
}
Expand Down Expand Up @@ -2993,7 +2993,7 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,

scaled_busy_load_per_task = sds->busiest_load_per_task
* SCHED_POWER_SCALE;
scaled_busy_load_per_task /= sds->busiest->cpu_power;
scaled_busy_load_per_task /= sds->busiest->sgp->power;

if (sds->max_load - sds->this_load + scaled_busy_load_per_task >=
(scaled_busy_load_per_task * imbn)) {
Expand All @@ -3007,28 +3007,28 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
* moving them.
*/

pwr_now += sds->busiest->cpu_power *
pwr_now += sds->busiest->sgp->power *
min(sds->busiest_load_per_task, sds->max_load);
pwr_now += sds->this->cpu_power *
pwr_now += sds->this->sgp->power *
min(sds->this_load_per_task, sds->this_load);
pwr_now /= SCHED_POWER_SCALE;

/* Amount of load we'd subtract */
tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
sds->busiest->cpu_power;
sds->busiest->sgp->power;
if (sds->max_load > tmp)
pwr_move += sds->busiest->cpu_power *
pwr_move += sds->busiest->sgp->power *
min(sds->busiest_load_per_task, sds->max_load - tmp);

/* Amount of load we'd add */
if (sds->max_load * sds->busiest->cpu_power <
if (sds->max_load * sds->busiest->sgp->power <
sds->busiest_load_per_task * SCHED_POWER_SCALE)
tmp = (sds->max_load * sds->busiest->cpu_power) /
sds->this->cpu_power;
tmp = (sds->max_load * sds->busiest->sgp->power) /
sds->this->sgp->power;
else
tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
sds->this->cpu_power;
pwr_move += sds->this->cpu_power *
sds->this->sgp->power;
pwr_move += sds->this->sgp->power *
min(sds->this_load_per_task, sds->this_load + tmp);
pwr_move /= SCHED_POWER_SCALE;

Expand Down Expand Up @@ -3074,7 +3074,7 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,

load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_POWER_SCALE);

load_above_capacity /= sds->busiest->cpu_power;
load_above_capacity /= sds->busiest->sgp->power;
}

/*
Expand All @@ -3090,8 +3090,8 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
max_pull = min(sds->max_load - sds->avg_load, load_above_capacity);

/* How much load to actually move to equalise the imbalance */
*imbalance = min(max_pull * sds->busiest->cpu_power,
(sds->avg_load - sds->this_load) * sds->this->cpu_power)
*imbalance = min(max_pull * sds->busiest->sgp->power,
(sds->avg_load - sds->this_load) * sds->this->sgp->power)
/ SCHED_POWER_SCALE;

/*
Expand Down

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