From: Nikhil Rao <ncrao@google.com>
To: Ingo Molnar <mingo@elte.hu>,
Peter Zijlstra <peterz@infradead.org>,
Mike Galbraith <efault@gmx.de>
Cc: linux-kernel@vger.kernel.org,
"Nikunj A. Dadhania" <nikunj@linux.vnet.ibm.com>,
Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
Stephan Barwolf <stephan.baerwolf@tu-ilmenau.de>,
Nikhil Rao <ncrao@google.com>
Subject: [PATCH v1 01/19] sched: introduce SCHED_POWER_SCALE to scale cpu_power calculations
Date: Sun, 1 May 2011 18:18:59 -0700 [thread overview]
Message-ID: <1304299157-25769-2-git-send-email-ncrao@google.com> (raw)
In-Reply-To: <1304299157-25769-1-git-send-email-ncrao@google.com>
SCHED_LOAD_SCALE is used to increase nice resolution and to scale cpu_power
calculations in the scheduler. This patch introduces SCHED_POWER_SCALE and
converts all uses of SCHED_LOAD_SCALE for scaling cpu_power to use
SCHED_POWER_SCALE instead.
This is a preparatory patch for increasing the resolution of SCHED_LOAD_SCALE,
and there is no need to increase resolution for cpu_power calculations.
Signed-off-by: Nikhil Rao <ncrao@google.com>
---
include/linux/sched.h | 13 +++++++----
kernel/sched.c | 11 ++++-----
kernel/sched_fair.c | 52 +++++++++++++++++++++++++-----------------------
3 files changed, 40 insertions(+), 36 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 18d63ce..8d1ff2b 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -792,17 +792,20 @@ enum cpu_idle_type {
};
/*
- * sched-domains (multiprocessor balancing) declarations:
- */
-
-/*
* Increase resolution of nice-level calculations:
*/
#define SCHED_LOAD_SHIFT 10
#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
-#define SCHED_LOAD_SCALE_FUZZ SCHED_LOAD_SCALE
+/*
+ * Increase resolution of cpu_power calculations
+ */
+#define SCHED_POWER_SHIFT 10
+#define SCHED_POWER_SCALE (1L << SCHED_POWER_SHIFT)
+/*
+ * sched-domains (multiprocessor balancing) declarations:
+ */
#ifdef CONFIG_SMP
#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */
#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */
diff --git a/kernel/sched.c b/kernel/sched.c
index 312f8b9..f4b4679 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1302,8 +1302,7 @@ static void sched_avg_update(struct rq *rq)
* delta *= weight / lw
*/
static unsigned long
-calc_delta_mine(unsigned long delta_exec, unsigned long weight,
- struct load_weight *lw)
+calc_delta_mine(unsigned long delta_exec, u64 weight, struct load_weight *lw)
{
u64 tmp;
@@ -6468,7 +6467,7 @@ 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);
}
@@ -7176,7 +7175,7 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
sd->groups->cpu_power = 0;
if (!child) {
- power = SCHED_LOAD_SCALE;
+ power = SCHED_POWER_SCALE;
weight = cpumask_weight(sched_domain_span(sd));
/*
* SMT siblings share the power of a single core.
@@ -7187,7 +7186,7 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
power *= sd->smt_gain;
power /= weight;
- power >>= SCHED_LOAD_SHIFT;
+ power >>= SCHED_POWER_SHIFT;
}
sd->groups->cpu_power += power;
return;
@@ -8224,7 +8223,7 @@ 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;
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 6fa833a..1a9340c 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1557,7 +1557,7 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
}
/* Adjust by relative CPU power of the group */
- avg_load = (avg_load * SCHED_LOAD_SCALE) / group->cpu_power;
+ avg_load = (avg_load * SCHED_POWER_SCALE) / group->cpu_power;
if (local_group) {
this_load = avg_load;
@@ -1692,7 +1692,7 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_
nr_running += cpu_rq(i)->cfs.nr_running;
}
- capacity = DIV_ROUND_CLOSEST(power, SCHED_LOAD_SCALE);
+ capacity = DIV_ROUND_CLOSEST(power, SCHED_POWER_SCALE);
if (tmp->flags & SD_POWERSAVINGS_BALANCE)
nr_running /= 2;
@@ -2534,7 +2534,7 @@ static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu)
{
- return SCHED_LOAD_SCALE;
+ return SCHED_POWER_SCALE;
}
unsigned long __weak arch_scale_freq_power(struct sched_domain *sd, int cpu)
@@ -2571,10 +2571,10 @@ unsigned long scale_rt_power(int cpu)
available = total - rq->rt_avg;
}
- if (unlikely((s64)total < SCHED_LOAD_SCALE))
- total = SCHED_LOAD_SCALE;
+ if (unlikely((s64)total < SCHED_POWER_SCALE))
+ total = SCHED_POWER_SCALE;
- total >>= SCHED_LOAD_SHIFT;
+ total >>= SCHED_POWER_SHIFT;
return div_u64(available, total);
}
@@ -2582,7 +2582,7 @@ unsigned long scale_rt_power(int cpu)
static void update_cpu_power(struct sched_domain *sd, int cpu)
{
unsigned long weight = sd->span_weight;
- unsigned long power = SCHED_LOAD_SCALE;
+ unsigned long power = SCHED_POWER_SCALE;
struct sched_group *sdg = sd->groups;
if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
@@ -2591,7 +2591,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
else
power *= default_scale_smt_power(sd, cpu);
- power >>= SCHED_LOAD_SHIFT;
+ power >>= SCHED_POWER_SHIFT;
}
sdg->cpu_power_orig = power;
@@ -2601,10 +2601,10 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
else
power *= default_scale_freq_power(sd, cpu);
- power >>= SCHED_LOAD_SHIFT;
+ power >>= SCHED_POWER_SHIFT;
power *= scale_rt_power(cpu);
- power >>= SCHED_LOAD_SHIFT;
+ power >>= SCHED_POWER_SHIFT;
if (!power)
power = 1;
@@ -2646,7 +2646,7 @@ static inline int
fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
{
/*
- * Only siblings can have significantly less than SCHED_LOAD_SCALE
+ * Only siblings can have significantly less than SCHED_POWER_SCALE
*/
if (sd->level != SD_LV_SIBLING)
return 0;
@@ -2734,7 +2734,7 @@ 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_LOAD_SCALE) / group->cpu_power;
+ sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->cpu_power;
/*
* Consider the group unbalanced when the imbalance is larger
@@ -2751,7 +2751,8 @@ 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, SCHED_LOAD_SCALE);
+ sgs->group_capacity = DIV_ROUND_CLOSEST(group->cpu_power,
+ SCHED_POWER_SCALE);
if (!sgs->group_capacity)
sgs->group_capacity = fix_small_capacity(sd, group);
sgs->group_weight = group->group_weight;
@@ -2925,7 +2926,7 @@ static int check_asym_packing(struct sched_domain *sd,
return 0;
*imbalance = DIV_ROUND_CLOSEST(sds->max_load * sds->busiest->cpu_power,
- SCHED_LOAD_SCALE);
+ SCHED_POWER_SCALE);
return 1;
}
@@ -2954,7 +2955,7 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
cpu_avg_load_per_task(this_cpu);
scaled_busy_load_per_task = sds->busiest_load_per_task
- * SCHED_LOAD_SCALE;
+ * SCHED_POWER_SCALE;
scaled_busy_load_per_task /= sds->busiest->cpu_power;
if (sds->max_load - sds->this_load + scaled_busy_load_per_task >=
@@ -2973,10 +2974,10 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
min(sds->busiest_load_per_task, sds->max_load);
pwr_now += sds->this->cpu_power *
min(sds->this_load_per_task, sds->this_load);
- pwr_now /= SCHED_LOAD_SCALE;
+ pwr_now /= SCHED_POWER_SCALE;
/* Amount of load we'd subtract */
- tmp = (sds->busiest_load_per_task * SCHED_LOAD_SCALE) /
+ tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
sds->busiest->cpu_power;
if (sds->max_load > tmp)
pwr_move += sds->busiest->cpu_power *
@@ -2984,15 +2985,15 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
/* Amount of load we'd add */
if (sds->max_load * sds->busiest->cpu_power <
- sds->busiest_load_per_task * SCHED_LOAD_SCALE)
+ sds->busiest_load_per_task * SCHED_POWER_SCALE)
tmp = (sds->max_load * sds->busiest->cpu_power) /
sds->this->cpu_power;
else
- tmp = (sds->busiest_load_per_task * SCHED_LOAD_SCALE) /
+ tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
sds->this->cpu_power;
pwr_move += sds->this->cpu_power *
min(sds->this_load_per_task, sds->this_load + tmp);
- pwr_move /= SCHED_LOAD_SCALE;
+ pwr_move /= SCHED_POWER_SCALE;
/* Move if we gain throughput */
if (pwr_move > pwr_now)
@@ -3034,7 +3035,7 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
load_above_capacity = (sds->busiest_nr_running -
sds->busiest_group_capacity);
- load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_LOAD_SCALE);
+ load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_POWER_SCALE);
load_above_capacity /= sds->busiest->cpu_power;
}
@@ -3054,7 +3055,7 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
/* 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)
- / SCHED_LOAD_SCALE;
+ / SCHED_POWER_SCALE;
/*
* if *imbalance is less than the average load per runnable task
@@ -3123,7 +3124,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
if (!sds.busiest || sds.busiest_nr_running == 0)
goto out_balanced;
- sds.avg_load = (SCHED_LOAD_SCALE * sds.total_load) / sds.total_pwr;
+ sds.avg_load = (SCHED_POWER_SCALE * sds.total_load) / sds.total_pwr;
/*
* If the busiest group is imbalanced the below checks don't
@@ -3202,7 +3203,8 @@ find_busiest_queue(struct sched_domain *sd, struct sched_group *group,
for_each_cpu(i, sched_group_cpus(group)) {
unsigned long power = power_of(i);
- unsigned long capacity = DIV_ROUND_CLOSEST(power, SCHED_LOAD_SCALE);
+ unsigned long capacity = DIV_ROUND_CLOSEST(power,
+ SCHED_POWER_SCALE);
unsigned long wl;
if (!capacity)
@@ -3227,7 +3229,7 @@ find_busiest_queue(struct sched_domain *sd, struct sched_group *group,
* the load can be moved away from the cpu that is potentially
* running at a lower capacity.
*/
- wl = (wl * SCHED_LOAD_SCALE) / power;
+ wl = (wl * SCHED_POWER_SCALE) / power;
if (wl > max_load) {
max_load = wl;
--
1.7.3.1
next prev parent reply other threads:[~2011-05-02 1:23 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-02 1:18 [PATCH v1 00/19] Increase resolution of load weights Nikhil Rao
2011-05-02 1:18 ` Nikhil Rao [this message]
2011-05-02 1:19 ` [PATCH v1 02/19] sched: increase SCHED_LOAD_SCALE resolution Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 03/19] sched: use u64 for load_weight fields Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 04/19] sched: update cpu_load to be u64 Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 05/19] sched: update this_cpu_load() to return u64 value Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 06/19] sched: update source_load(), target_load() and weighted_cpuload() to use u64 Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 07/19] sched: update find_idlest_cpu() to use u64 for load Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 08/19] sched: update find_idlest_group() to use u64 Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 09/19] sched: update division in cpu_avg_load_per_task to use div_u64 Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 10/19] sched: update wake_affine path to use u64, s64 for weights Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 11/19] sched: update update_sg_lb_stats() to use u64 Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 12/19] sched: Update update_sd_lb_stats() " Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 13/19] sched: update f_b_g() to use u64 for weights Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 14/19] sched: change type of imbalance to be u64 Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 15/19] sched: update h_load to use u64 Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 16/19] sched: update move_task() and helper functions to use u64 for weights Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 17/19] sched: update f_b_q() to use u64 for weighted cpuload Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 18/19] sched: update shares distribution to use u64 Nikhil Rao
2011-05-02 1:19 ` [PATCH v1 19/19] sched: convert atomic ops in shares update to use atomic64_t ops Nikhil Rao
2011-05-02 6:14 ` [PATCH v1 00/19] Increase resolution of load weights Ingo Molnar
2011-05-04 0:58 ` Nikhil Rao
2011-05-04 1:07 ` Nikhil Rao
2011-05-04 11:13 ` Ingo Molnar
2011-05-06 1:29 ` Nikhil Rao
2011-05-06 6:59 ` Ingo Molnar
2011-05-11 0:14 ` Nikhil Rao
2011-05-11 6:59 ` Ingo Molnar
2011-05-12 8:56 ` Nikhil Rao
2011-05-12 10:55 ` Ingo Molnar
2011-05-12 18:44 ` Nikhil Rao
2011-05-12 9:08 ` Peter Zijlstra
2011-05-12 17:30 ` Nikhil Rao
2011-05-13 7:19 ` Peter Zijlstra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1304299157-25769-2-git-send-email-ncrao@google.com \
--to=ncrao@google.com \
--cc=efault@gmx.de \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=nikunj@linux.vnet.ibm.com \
--cc=peterz@infradead.org \
--cc=stephan.baerwolf@tu-ilmenau.de \
--cc=vatsa@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.