Evolution-X-Devices/kernel_google_wahoo
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

cpufreq: interactive: adjust load for changes in speed

Browse Source 
Add notifier for speed transitions.  Keep a count of CPU active
microseconds times current frequency, converted to a percentage relative
to the current frequency when load is evaluated.

Change-Id: I5c27adb11081c50490219784ca57cc46e97fc28c
Signed-off-by: Todd Poynor <toddpoynor@google.com>
This commit is contained in:
Todd Poynor
2012-12-11 16:05:03 -08:00
committed by John Stultz
parent 482f37e3d8
commit 2c2b492e77
1 changed files with 71 additions and 16 deletions
Download Patch File Download Diff File Expand all files Collapse all files

87
drivers/cpufreq/cpufreq_interactive.c
View File

@@ -41,8 +41,11 @@ static atomic_t active_count = ATOMIC_INIT(0);
struct cpufreq_interactive_cpuinfo {
struct timer_list cpu_timer;
int timer_idlecancel;
spinlock_t load_lock; /* protects the next 4 fields */
u64 time_in_idle;
u64 time_in_idle_timestamp;
u64 cputime_speedadj;
u64 cputime_speedadj_timestamp;
struct cpufreq_policy *policy;
struct cpufreq_frequency_table *freq_table;
unsigned int target_freq;
@@ -121,9 +124,13 @@ static void cpufreq_interactive_timer_resched(
{
mod_timer_pinned(&pcpu->cpu_timer,
jiffies + usecs_to_jiffies(timer_rate));
spin_lock(&pcpu->load_lock);
pcpu->time_in_idle =
get_cpu_idle_time_us(smp_processor_id(),
&pcpu->time_in_idle_timestamp);
pcpu->cputime_speedadj = 0;
pcpu->cputime_speedadj_timestamp = pcpu->time_in_idle_timestamp;
spin_unlock(&pcpu->load_lock);
}
static unsigned int freq_to_targetload(unsigned int freq)
@@ -148,10 +155,9 @@ static unsigned int freq_to_targetload(unsigned int freq)
*/
static unsigned int choose_freq(
struct cpufreq_interactive_cpuinfo *pcpu, unsigned int curload)
struct cpufreq_interactive_cpuinfo *pcpu, unsigned int loadadjfreq)
{
unsigned int freq = pcpu->policy->cur;
unsigned int loadadjfreq = freq * curload;
unsigned int prevfreq, freqmin, freqmax;
unsigned int tl;
int index;
@@ -230,16 +236,36 @@ static unsigned int choose_freq(
return freq;
}
static u64 update_load(int cpu)
{
struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
u64 now;
u64 now_idle;
unsigned int delta_idle;
unsigned int delta_time;
u64 active_time;
now_idle = get_cpu_idle_time_us(cpu, &now);
delta_idle = (unsigned int)(now_idle - pcpu->time_in_idle);
delta_time = (unsigned int)(now - pcpu->time_in_idle_timestamp);
active_time = delta_time - delta_idle;
pcpu->cputime_speedadj += active_time * pcpu->policy->cur;
pcpu->time_in_idle = now_idle;
pcpu->time_in_idle_timestamp = now;
return now;
}
static void cpufreq_interactive_timer(unsigned long data)
{
u64 now;
unsigned int delta_idle;
unsigned int delta_time;
u64 cputime_speedadj;
int cpu_load;
struct cpufreq_interactive_cpuinfo *pcpu =
&per_cpu(cpuinfo, data);
u64 now_idle;
unsigned int new_freq;
unsigned int loadadjfreq;
unsigned int index;
unsigned long flags;
@@ -248,26 +274,24 @@ static void cpufreq_interactive_timer(unsigned long data)
if (!pcpu->governor_enabled)
goto exit;
now_idle = get_cpu_idle_time_us(data, &now);
delta_idle = (unsigned int)(now_idle - pcpu->time_in_idle);
delta_time = (unsigned int)(now - pcpu->time_in_idle_timestamp);
spin_lock(&pcpu->load_lock);
now = update_load(data);
delta_time = (unsigned int)(now - pcpu->cputime_speedadj_timestamp);
cputime_speedadj = pcpu->cputime_speedadj;
spin_unlock(&pcpu->load_lock);
/*
* If timer ran less than 1ms after short-term sample started, retry.
*/
if (delta_time < 1000)
if (WARN_ON_ONCE(!delta_time))
goto rearm;
if (delta_idle > delta_time)
cpu_load = 0;
else
cpu_load = 100 * (delta_time - delta_idle) / delta_time;
do_div(cputime_speedadj, delta_time);
loadadjfreq = (unsigned int)cputime_speedadj * 100;
cpu_load = loadadjfreq / pcpu->target_freq;
if ((cpu_load >= go_hispeed_load || boost_val) &&
pcpu->target_freq < hispeed_freq)
new_freq = hispeed_freq;
else
new_freq = choose_freq(pcpu, cpu_load);
new_freq = choose_freq(pcpu, loadadjfreq);
if (pcpu->target_freq >= hispeed_freq &&
new_freq > pcpu->target_freq &&
@@ -498,6 +522,32 @@ static void cpufreq_interactive_boost(void)
wake_up_process(speedchange_task);
}
static int cpufreq_interactive_notifier(
struct notifier_block *nb, unsigned long val, void *data)
{
struct cpufreq_freqs *freq = data;
struct cpufreq_interactive_cpuinfo *pcpu;
int cpu;
if (val == CPUFREQ_POSTCHANGE) {
pcpu = &per_cpu(cpuinfo, freq->cpu);
for_each_cpu(cpu, pcpu->policy->cpus) {
struct cpufreq_interactive_cpuinfo *pjcpu =
&per_cpu(cpuinfo, cpu);
spin_lock(&pjcpu->load_lock);
update_load(cpu);
spin_unlock(&pjcpu->load_lock);
}
}
return 0;
}
static struct notifier_block cpufreq_notifier_block = {
.notifier_call = cpufreq_interactive_notifier,
};
static ssize_t show_target_loads(
struct kobject *kobj, struct attribute *attr, char *buf)
{
@@ -817,6 +867,8 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
return rc;
idle_notifier_register(&cpufreq_interactive_idle_nb);
cpufreq_register_notifier(
&cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
break;
case CPUFREQ_GOV_STOP:
@@ -830,6 +882,8 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
if (atomic_dec_return(&active_count) > 0)
return 0;
cpufreq_unregister_notifier(
&cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
idle_notifier_unregister(&cpufreq_interactive_idle_nb);
sysfs_remove_group(cpufreq_global_kobject,
&interactive_attr_group);
@@ -868,6 +922,7 @@ static int __init cpufreq_interactive_init(void)
init_timer_deferrable(&pcpu->cpu_timer);
pcpu->cpu_timer.function = cpufreq_interactive_timer;
pcpu->cpu_timer.data = i;
spin_lock_init(&pcpu->load_lock);
}
spin_lock_init(&target_loads_lock);