mirror of
https://github.com/torvalds/linux.git
synced 2024-11-15 16:41:58 +00:00
10dd8573b0
Currently, most CPUFreq governors are registered at the core_initcall
time when the given governor is the default one, and the module_init
time otherwise.
In preparation for letting users specify the default governor on the
kernel command line, change all of them to be registered at the
core_initcall unconditionally, as it is already the case for the
schedutil and performance governors. This will allow us to assume
that builtin governors have been registered before the built-in
CPUFreq drivers probe.
And since all governors have similar init/exit patterns now, introduce
two new macros, cpufreq_governor_{init,exit}(), to factorize the code.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
134 lines
3.3 KiB
C
134 lines
3.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* spu aware cpufreq governor for the cell processor
|
|
*
|
|
* © Copyright IBM Corporation 2006-2008
|
|
*
|
|
* Author: Christian Krafft <krafft@de.ibm.com>
|
|
*/
|
|
|
|
#include <linux/cpufreq.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/sched/loadavg.h>
|
|
#include <linux/module.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/atomic.h>
|
|
#include <asm/machdep.h>
|
|
#include <asm/spu.h>
|
|
|
|
#define POLL_TIME 100000 /* in µs */
|
|
#define EXP 753 /* exp(-1) in fixed-point */
|
|
|
|
struct spu_gov_info_struct {
|
|
unsigned long busy_spus; /* fixed-point */
|
|
struct cpufreq_policy *policy;
|
|
struct delayed_work work;
|
|
unsigned int poll_int; /* µs */
|
|
};
|
|
static DEFINE_PER_CPU(struct spu_gov_info_struct, spu_gov_info);
|
|
|
|
static int calc_freq(struct spu_gov_info_struct *info)
|
|
{
|
|
int cpu;
|
|
int busy_spus;
|
|
|
|
cpu = info->policy->cpu;
|
|
busy_spus = atomic_read(&cbe_spu_info[cpu_to_node(cpu)].busy_spus);
|
|
|
|
info->busy_spus = calc_load(info->busy_spus, EXP, busy_spus * FIXED_1);
|
|
pr_debug("cpu %d: busy_spus=%d, info->busy_spus=%ld\n",
|
|
cpu, busy_spus, info->busy_spus);
|
|
|
|
return info->policy->max * info->busy_spus / FIXED_1;
|
|
}
|
|
|
|
static void spu_gov_work(struct work_struct *work)
|
|
{
|
|
struct spu_gov_info_struct *info;
|
|
int delay;
|
|
unsigned long target_freq;
|
|
|
|
info = container_of(work, struct spu_gov_info_struct, work.work);
|
|
|
|
/* after cancel_delayed_work_sync we unset info->policy */
|
|
BUG_ON(info->policy == NULL);
|
|
|
|
target_freq = calc_freq(info);
|
|
__cpufreq_driver_target(info->policy, target_freq, CPUFREQ_RELATION_H);
|
|
|
|
delay = usecs_to_jiffies(info->poll_int);
|
|
schedule_delayed_work_on(info->policy->cpu, &info->work, delay);
|
|
}
|
|
|
|
static void spu_gov_init_work(struct spu_gov_info_struct *info)
|
|
{
|
|
int delay = usecs_to_jiffies(info->poll_int);
|
|
INIT_DEFERRABLE_WORK(&info->work, spu_gov_work);
|
|
schedule_delayed_work_on(info->policy->cpu, &info->work, delay);
|
|
}
|
|
|
|
static void spu_gov_cancel_work(struct spu_gov_info_struct *info)
|
|
{
|
|
cancel_delayed_work_sync(&info->work);
|
|
}
|
|
|
|
static int spu_gov_start(struct cpufreq_policy *policy)
|
|
{
|
|
unsigned int cpu = policy->cpu;
|
|
struct spu_gov_info_struct *info = &per_cpu(spu_gov_info, cpu);
|
|
struct spu_gov_info_struct *affected_info;
|
|
int i;
|
|
|
|
if (!cpu_online(cpu)) {
|
|
printk(KERN_ERR "cpu %d is not online\n", cpu);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!policy->cur) {
|
|
printk(KERN_ERR "no cpu specified in policy\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* initialize spu_gov_info for all affected cpus */
|
|
for_each_cpu(i, policy->cpus) {
|
|
affected_info = &per_cpu(spu_gov_info, i);
|
|
affected_info->policy = policy;
|
|
}
|
|
|
|
info->poll_int = POLL_TIME;
|
|
|
|
/* setup timer */
|
|
spu_gov_init_work(info);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void spu_gov_stop(struct cpufreq_policy *policy)
|
|
{
|
|
unsigned int cpu = policy->cpu;
|
|
struct spu_gov_info_struct *info = &per_cpu(spu_gov_info, cpu);
|
|
int i;
|
|
|
|
/* cancel timer */
|
|
spu_gov_cancel_work(info);
|
|
|
|
/* clean spu_gov_info for all affected cpus */
|
|
for_each_cpu (i, policy->cpus) {
|
|
info = &per_cpu(spu_gov_info, i);
|
|
info->policy = NULL;
|
|
}
|
|
}
|
|
|
|
static struct cpufreq_governor spu_governor = {
|
|
.name = "spudemand",
|
|
.start = spu_gov_start,
|
|
.stop = spu_gov_stop,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
cpufreq_governor_init(spu_governor);
|
|
cpufreq_governor_exit(spu_governor);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Christian Krafft <krafft@de.ibm.com>");
|