1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
/* Copyright (c) 2012, 2015-2017, 2018 The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
/*
* Scheduler hook for average runqueue determination
*/
#include <linux/module.h>
#include <linux/percpu.h>
#include <linux/hrtimer.h>
#include <linux/sched.h>
#include <linux/math64.h>
#include "sched.h"
#include <trace/events/sched.h>
static DEFINE_PER_CPU(u64, nr_prod_sum);
static DEFINE_PER_CPU(u64, last_time);
static DEFINE_PER_CPU(u64, nr_big_prod_sum);
static DEFINE_PER_CPU(u64, nr);
static DEFINE_PER_CPU(u64, nr_max);
static DEFINE_PER_CPU(unsigned long, iowait_prod_sum);
static DEFINE_PER_CPU(spinlock_t, nr_lock) = __SPIN_LOCK_UNLOCKED(nr_lock);
static s64 last_get_time;
#define DIV64_U64_ROUNDUP(X, Y) div64_u64((X) + (Y - 1), Y)
/**
* sched_get_nr_running_avg
* @return: Average nr_running, iowait and nr_big_tasks value since last poll.
* Returns the avg * 100 to return up to two decimal points
* of accuracy.
*
* Obtains the average nr_running value since the last poll.
* This function may not be called concurrently with itself
*/
void sched_get_nr_running_avg(int *avg, int *iowait_avg, int *big_avg,
unsigned int *max_nr, unsigned int *big_max_nr)
{
int cpu;
u64 curr_time = sched_clock();
u64 diff = curr_time - last_get_time;
u64 tmp_avg = 0, tmp_iowait = 0, tmp_big_avg = 0;
*avg = 0;
*iowait_avg = 0;
*big_avg = 0;
*max_nr = 0;
*big_max_nr = 0;
if (!diff)
return;
/* read and reset nr_running counts */
for_each_possible_cpu(cpu) {
unsigned long flags;
spin_lock_irqsave(&per_cpu(nr_lock, cpu), flags);
curr_time = sched_clock();
diff = curr_time - per_cpu(last_time, cpu);
BUG_ON((s64)diff < 0);
tmp_avg += per_cpu(nr_prod_sum, cpu);
tmp_avg += per_cpu(nr, cpu) * diff;
tmp_big_avg += per_cpu(nr_big_prod_sum, cpu);
tmp_big_avg += nr_eligible_big_tasks(cpu) * diff;
tmp_iowait += per_cpu(iowait_prod_sum, cpu);
tmp_iowait += nr_iowait_cpu(cpu) * diff;
per_cpu(last_time, cpu) = curr_time;
per_cpu(nr_prod_sum, cpu) = 0;
per_cpu(nr_big_prod_sum, cpu) = 0;
per_cpu(iowait_prod_sum, cpu) = 0;
if (*max_nr < per_cpu(nr_max, cpu))
*max_nr = per_cpu(nr_max, cpu);
if (is_max_capacity_cpu(cpu)) {
if (*big_max_nr < per_cpu(nr_max, cpu))
*big_max_nr = per_cpu(nr_max, cpu);
}
per_cpu(nr_max, cpu) = per_cpu(nr, cpu);
spin_unlock_irqrestore(&per_cpu(nr_lock, cpu), flags);
}
diff = curr_time - last_get_time;
last_get_time = curr_time;
/*
* Any task running on BIG cluster and BIG tasks running on little
* cluster contributes to big_avg. Small or medium tasks can also
* run on BIG cluster when co-location and scheduler boost features
* are activated. We don't want these tasks to downmigrate to little
* cluster when BIG CPUs are available but isolated. Round up the
* average values so that core_ctl aggressively unisolate BIG CPUs.
*/
*avg = (int)DIV64_U64_ROUNDUP(tmp_avg, diff);
*big_avg = (int)DIV64_U64_ROUNDUP(tmp_big_avg, diff);
*iowait_avg = (int)DIV64_U64_ROUNDUP(tmp_iowait, diff);
trace_sched_get_nr_running_avg(*avg, *big_avg, *iowait_avg,
*max_nr, *big_max_nr);
BUG_ON(*avg < 0 || *big_avg < 0 || *iowait_avg < 0);
pr_debug("%s - avg:%d big_avg:%d iowait_avg:%d\n",
__func__, *avg, *big_avg, *iowait_avg);
}
EXPORT_SYMBOL(sched_get_nr_running_avg);
static DEFINE_PER_CPU(atomic64_t, last_busy_time) = ATOMIC64_INIT(0);
#define BUSY_NR_RUN 3
#define BUSY_LOAD_FACTOR 10
#ifdef CONFIG_SCHED_HMP
static inline void update_last_busy_time(int cpu, bool dequeue,
unsigned long prev_nr_run, u64 curr_time)
{
bool nr_run_trigger = false, load_trigger = false;
if (!hmp_capable() || is_min_capacity_cpu(cpu))
return;
if (prev_nr_run >= BUSY_NR_RUN && per_cpu(nr, cpu) < BUSY_NR_RUN)
nr_run_trigger = true;
if (dequeue) {
u64 load;
load = cpu_rq(cpu)->hmp_stats.cumulative_runnable_avg;
load = scale_load_to_cpu(load, cpu);
if (load * BUSY_LOAD_FACTOR > sched_ravg_window)
load_trigger = true;
}
if (nr_run_trigger || load_trigger)
atomic64_set(&per_cpu(last_busy_time, cpu), curr_time);
}
#else
static inline void update_last_busy_time(int cpu, bool dequeue,
unsigned long prev_nr_run, u64 curr_time)
{
}
#endif
/**
* sched_update_nr_prod
* @cpu: The core id of the nr running driver.
* @delta: Adjust nr by 'delta' amount
* @inc: Whether we are increasing or decreasing the count
* @return: N/A
*
* Update average with latest nr_running value for CPU
*/
void sched_update_nr_prod(int cpu, long delta, bool inc)
{
u64 diff;
u64 curr_time;
unsigned long flags, nr_running;
spin_lock_irqsave(&per_cpu(nr_lock, cpu), flags);
nr_running = per_cpu(nr, cpu);
curr_time = sched_clock();
diff = curr_time - per_cpu(last_time, cpu);
BUG_ON((s64)diff < 0);
per_cpu(last_time, cpu) = curr_time;
per_cpu(nr, cpu) = nr_running + (inc ? delta : -delta);
BUG_ON((s64)per_cpu(nr, cpu) < 0);
if (per_cpu(nr, cpu) > per_cpu(nr_max, cpu))
per_cpu(nr_max, cpu) = per_cpu(nr, cpu);
update_last_busy_time(cpu, !inc, nr_running, curr_time);
per_cpu(nr_prod_sum, cpu) += nr_running * diff;
per_cpu(nr_big_prod_sum, cpu) += nr_eligible_big_tasks(cpu) * diff;
per_cpu(iowait_prod_sum, cpu) += nr_iowait_cpu(cpu) * diff;
spin_unlock_irqrestore(&per_cpu(nr_lock, cpu), flags);
}
EXPORT_SYMBOL(sched_update_nr_prod);
u64 sched_get_cpu_last_busy_time(int cpu)
{
return atomic64_read(&per_cpu(last_busy_time, cpu));
}
|