system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-10-04 18:33:42 +00:00
Code Issues Packages Projects Releases Wiki Activity

Merge branches 'pm-cpuidle' and 'pm-cpufreq'

Browse source 
Merge CPU power management updates for 6.6-rc1:

 - Rework the menu and teo cpuidle governors to avoid calling
   tick_nohz_get_sleep_length(), which is likely to become quite
   expensive going forward, too often and improve making decisions
   regarding whether or not to stop the scheduler tick in the teo
   governor (Rafael Wysocki).

 - Improve the performance of cpufreq_stats_create_table() in some
   cases (Liao Chang).

 - Fix two issues in the amd-pstate-ut cpufreq driver (Swapnil Sapkal).

 - Use clamp() helper macro to improve the code readability in
   cpufreq_verify_within_limits() (Liao Chang).

 - Set stale CPU frequency to minimum in intel_pstate (Doug Smythies).

* pm-cpuidle:
  cpuidle: teo: Avoid unnecessary variable assignments
  cpuidle: menu: Skip tick_nohz_get_sleep_length() call in some cases
  cpuidle: teo: Gather statistics regarding whether or not to stop the tick
  cpuidle: teo: Skip tick_nohz_get_sleep_length() call in some cases
  cpuidle: teo: Do not call tick_nohz_get_sleep_length() upfront
  cpuidle: teo: Drop utilized from struct teo_cpu
  cpuidle: teo: Avoid stopping the tick unnecessarily when bailing out
  cpuidle: teo: Update idle duration estimate when choosing shallower state

* pm-cpufreq:
  cpufreq: amd-pstate-ut: Fix kernel panic when loading the driver
  cpufreq: amd-pstate-ut: Remove module parameter access
  cpufreq: Use clamp() helper macro to improve the code readability
  cpufreq: intel_pstate: set stale CPU frequency to minimum
  cpufreq: stats: Improve the performance of cpufreq_stats_create_table()
This commit is contained in:
Rafael J. Wysocki 2023-08-25 21:15:56 +02:00
parent e26a99dd15 78aabcb321 60dd283804
commit 1201c50c1e
7 changed files with 232 additions and 152 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

46
drivers/cpufreq/amd-pstate-ut.c
View file

@ -64,27 +64,9 @@ static struct amd_pstate_ut_struct amd_pstate_ut_cases[] = {
static bool get_shared_mem(void)
{
bool result = false;
char path[] = "/sys/module/amd_pstate/parameters/shared_mem";
char buf[5] = {0};
struct file *filp = NULL;
loff_t pos = 0;
ssize_t ret;
if (!boot_cpu_has(X86_FEATURE_CPPC)) {
filp = filp_open(path, O_RDONLY, 0);
if (IS_ERR(filp))
pr_err("%s unable to open %s file!\n", __func__, path);
else {
ret = kernel_read(filp, &buf, sizeof(buf), &pos);
if (ret < 0)
pr_err("%s read %s file fail ret=%ld!\n",
__func__, path, (long)ret);
filp_close(filp, NULL);
}
if ('Y' == *buf)
result = true;
}
if (!boot_cpu_has(X86_FEATURE_CPPC))
result = true;
return result;
}
@ -158,7 +140,7 @@ static void amd_pstate_ut_check_perf(u32 index)
if (ret) {
amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
pr_err("%s cppc_get_perf_caps ret=%d error!\n", __func__, ret);
return;
goto skip_test;
}
nominal_perf = cppc_perf.nominal_perf;
@ -169,7 +151,7 @@ static void amd_pstate_ut_check_perf(u32 index)
if (ret) {
amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
pr_err("%s read CPPC_CAP1 ret=%d error!\n", __func__, ret);
return;
goto skip_test;
}
nominal_perf = AMD_CPPC_NOMINAL_PERF(cap1);
@ -187,7 +169,7 @@ static void amd_pstate_ut_check_perf(u32 index)
nominal_perf, cpudata->nominal_perf,
lowest_nonlinear_perf, cpudata->lowest_nonlinear_perf,
lowest_perf, cpudata->lowest_perf);
return;
goto skip_test;
}
if (!((highest_perf >= nominal_perf) &&
@ -198,11 +180,15 @@ static void amd_pstate_ut_check_perf(u32 index)
pr_err("%s cpu%d highest=%d >= nominal=%d > lowest_nonlinear=%d > lowest=%d > 0, the formula is incorrect!\n",
__func__, cpu, highest_perf, nominal_perf,
lowest_nonlinear_perf, lowest_perf);
return;
goto skip_test;
}
cpufreq_cpu_put(policy);
}
amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
return;
skip_test:
cpufreq_cpu_put(policy);
}
/*
@ -230,14 +216,14 @@ static void amd_pstate_ut_check_freq(u32 index)
pr_err("%s cpu%d max=%d >= nominal=%d > lowest_nonlinear=%d > min=%d > 0, the formula is incorrect!\n",
__func__, cpu, cpudata->max_freq, cpudata->nominal_freq,
cpudata->lowest_nonlinear_freq, cpudata->min_freq);
return;
goto skip_test;
}
if (cpudata->min_freq != policy->min) {
amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
pr_err("%s cpu%d cpudata_min_freq=%d policy_min=%d, they should be equal!\n",
__func__, cpu, cpudata->min_freq, policy->min);
return;
goto skip_test;
}
if (cpudata->boost_supported) {
@ -249,16 +235,20 @@ static void amd_pstate_ut_check_freq(u32 index)
pr_err("%s cpu%d policy_max=%d should be equal cpu_max=%d or cpu_nominal=%d !\n",
__func__, cpu, policy->max, cpudata->max_freq,
cpudata->nominal_freq);
return;
goto skip_test;
}
} else {
amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_FAIL;
pr_err("%s cpu%d must support boost!\n", __func__, cpu);
return;
goto skip_test;
}
cpufreq_cpu_put(policy);
}
amd_pstate_ut_cases[index].result = AMD_PSTATE_UT_RESULT_PASS;
return;
skip_test:
cpufreq_cpu_put(policy);
}
static int __init amd_pstate_ut_init(void)

3
drivers/cpufreq/cpufreq_stats.c
View file

@ -243,7 +243,8 @@ void cpufreq_stats_create_table(struct cpufreq_policy *policy)
/* Find valid-unique entries */
cpufreq_for_each_valid_entry(pos, policy->freq_table)
if (freq_table_get_index(stats, pos->frequency) == -1)
if (policy->freq_table_sorted != CPUFREQ_TABLE_UNSORTED ||
freq_table_get_index(stats, pos->frequency) == -1)
stats->freq_table[i++] = pos->frequency;
stats->state_num = i;

5
drivers/cpufreq/intel_pstate.c
View file

@ -2609,6 +2609,11 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
intel_pstate_clear_update_util_hook(policy->cpu);
intel_pstate_hwp_set(policy->cpu);
}
/*
* policy->cur is never updated with the intel_pstate driver, but it
* is used as a stale frequency value. So, keep it within limits.
*/
policy->cur = policy->min;
mutex_unlock(&intel_pstate_limits_lock);

14
drivers/cpuidle/governors/gov.h Normal file
View file

@ -0,0 +1,14 @@
/* SPDX-License-Identifier: GPL-2.0 */
/* Common definitions for cpuidle governors. */
#ifndef __CPUIDLE_GOVERNOR_H
#define __CPUIDLE_GOVERNOR_H
/*
* Idle state target residency threshold used for deciding whether or not to
* check the time till the closest expected timer event.
*/
#define RESIDENCY_THRESHOLD_NS (15 * NSEC_PER_USEC)
#endif /* __CPUIDLE_GOVERNOR_H */

65
drivers/cpuidle/governors/menu.c
View file

@ -19,6 +19,8 @@
#include <linux/sched/stat.h>
#include <linux/math64.h>
#include "gov.h"
#define BUCKETS 12
#define INTERVAL_SHIFT 3
#define INTERVALS (1UL << INTERVAL_SHIFT)
@ -166,8 +168,7 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev);
* of points is below a threshold. If it is... then use the
* average of these 8 points as the estimated value.
*/
static unsigned int get_typical_interval(struct menu_device *data,
unsigned int predicted_us)
static unsigned int get_typical_interval(struct menu_device *data)
{
int i, divisor;
unsigned int min, max, thresh, avg;
@ -195,11 +196,7 @@ static unsigned int get_typical_interval(struct menu_device *data,
}
}
/*
* If the result of the computation is going to be discarded anyway,
* avoid the computation altogether.
*/
if (min >= predicted_us)
if (!max)
return UINT_MAX;
if (divisor == INTERVALS)
@ -267,7 +264,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
{
struct menu_device *data = this_cpu_ptr(&menu_devices);
s64 latency_req = cpuidle_governor_latency_req(dev->cpu);
unsigned int predicted_us;
u64 predicted_ns;
u64 interactivity_req;
unsigned int nr_iowaiters;
@ -279,16 +275,41 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
data->needs_update = 0;
}
/* determine the expected residency time, round up */
delta = tick_nohz_get_sleep_length(&delta_tick);
if (unlikely(delta < 0)) {
delta = 0;
delta_tick = 0;
}
data->next_timer_ns = delta;
nr_iowaiters = nr_iowait_cpu(dev->cpu);
data->bucket = which_bucket(data->next_timer_ns, nr_iowaiters);
/* Find the shortest expected idle interval. */
predicted_ns = get_typical_interval(data) * NSEC_PER_USEC;
if (predicted_ns > RESIDENCY_THRESHOLD_NS) {
unsigned int timer_us;
/* Determine the time till the closest timer. */
delta = tick_nohz_get_sleep_length(&delta_tick);
if (unlikely(delta < 0)) {
delta = 0;
delta_tick = 0;
}
data->next_timer_ns = delta;
data->bucket = which_bucket(data->next_timer_ns, nr_iowaiters);
/* Round up the result for half microseconds. */
timer_us = div_u64((RESOLUTION * DECAY * NSEC_PER_USEC) / 2 +
data->next_timer_ns *
data->correction_factor[data->bucket],
RESOLUTION * DECAY * NSEC_PER_USEC);
/* Use the lowest expected idle interval to pick the idle state. */
predicted_ns = min((u64)timer_us * NSEC_PER_USEC, predicted_ns);
} else {
/*
* Because the next timer event is not going to be determined
* in this case, assume that without the tick the closest timer
* will be in distant future and that the closest tick will occur
* after 1/2 of the tick period.
*/
data->next_timer_ns = KTIME_MAX;
delta_tick = TICK_NSEC / 2;
data->bucket = which_bucket(KTIME_MAX, nr_iowaiters);
}
if (unlikely(drv->state_count <= 1 || latency_req == 0) ||
((data->next_timer_ns < drv->states[1].target_residency_ns ||
@ -303,16 +324,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
return 0;
}
/* Round up the result for half microseconds. */
predicted_us = div_u64(data->next_timer_ns *
data->correction_factor[data->bucket] +
(RESOLUTION * DECAY * NSEC_PER_USEC) / 2,
RESOLUTION * DECAY * NSEC_PER_USEC);
/* Use the lowest expected idle interval to pick the idle state. */
predicted_ns = (u64)min(predicted_us,
get_typical_interval(data, predicted_us)) *
NSEC_PER_USEC;
if (tick_nohz_tick_stopped()) {
/*
* If the tick is already stopped, the cost of possible short

237
drivers/cpuidle/governors/teo.c
View file

@ -140,6 +140,8 @@
#include <linux/sched/topology.h>
#include <linux/tick.h>
#include "gov.h"
/*
* The number of bits to shift the CPU's capacity by in order to determine
* the utilized threshold.
@ -152,7 +154,6 @@
*/
#define UTIL_THRESHOLD_SHIFT 6
/*
* The PULSE value is added to metrics when they grow and the DECAY_SHIFT value
* is used for decreasing metrics on a regular basis.
@ -186,8 +187,8 @@ struct teo_bin {
* @total: Grand total of the "intercepts" and "hits" metrics for all bins.
* @next_recent_idx: Index of the next @recent_idx entry to update.
* @recent_idx: Indices of bins corresponding to recent "intercepts".
* @tick_hits: Number of "hits" after TICK_NSEC.
* @util_threshold: Threshold above which the CPU is considered utilized
* @utilized: Whether the last sleep on the CPU happened while utilized
*/
struct teo_cpu {
s64 time_span_ns;
@ -196,8 +197,8 @@ struct teo_cpu {
unsigned int total;
int next_recent_idx;
int recent_idx[NR_RECENT];
unsigned int tick_hits;
unsigned long util_threshold;
bool utilized;
};
static DEFINE_PER_CPU(struct teo_cpu, teo_cpus);
@ -228,6 +229,7 @@ static void teo_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
{
struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu);
int i, idx_timer = 0, idx_duration = 0;
s64 target_residency_ns;
u64 measured_ns;
if (cpu_data->time_span_ns >= cpu_data->sleep_length_ns) {
@ -268,7 +270,6 @@ static void teo_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
* fall into.
*/
for (i = 0; i < drv->state_count; i++) {
s64 target_residency_ns = drv->states[i].target_residency_ns;
struct teo_bin *bin = &cpu_data->state_bins[i];
bin->hits -= bin->hits >> DECAY_SHIFT;
@ -276,6 +277,8 @@ static void teo_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
cpu_data->total += bin->hits + bin->intercepts;
target_residency_ns = drv->states[i].target_residency_ns;
if (target_residency_ns <= cpu_data->sleep_length_ns) {
idx_timer = i;
if (target_residency_ns <= measured_ns)
@ -290,6 +293,26 @@ static void teo_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
if (cpu_data->recent_idx[i] >= 0)
cpu_data->state_bins[cpu_data->recent_idx[i]].recent--;
/*
* If the deepest state's target residency is below the tick length,
* make a record of it to help teo_select() decide whether or not
* to stop the tick. This effectively adds an extra hits-only bin
* beyond the last state-related one.
*/
if (target_residency_ns < TICK_NSEC) {
cpu_data->tick_hits -= cpu_data->tick_hits >> DECAY_SHIFT;
cpu_data->total += cpu_data->tick_hits;
if (TICK_NSEC <= cpu_data->sleep_length_ns) {
idx_timer = drv->state_count;
if (TICK_NSEC <= measured_ns) {
cpu_data->tick_hits += PULSE;
goto end;
}
}
}
/*
* If the measured idle duration falls into the same bin as the sleep
* length, this is a "hit", so update the "hits" metric for that bin.
@ -305,18 +328,14 @@ static void teo_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
cpu_data->recent_idx[i] = idx_duration;
}
end:
cpu_data->total += PULSE;
}
static bool teo_time_ok(u64 interval_ns)
static bool teo_state_ok(int i, struct cpuidle_driver *drv)
{
return !tick_nohz_tick_stopped() || interval_ns >= TICK_NSEC;
}
static s64 teo_middle_of_bin(int idx, struct cpuidle_driver *drv)
{
return (drv->states[idx].target_residency_ns +
drv->states[idx+1].target_residency_ns) / 2;
return !tick_nohz_tick_stopped() ||
drv->states[i].target_residency_ns >= TICK_NSEC;
}
/**
@ -356,6 +375,8 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
{
struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu);
s64 latency_req = cpuidle_governor_latency_req(dev->cpu);
ktime_t delta_tick = TICK_NSEC / 2;
unsigned int tick_intercept_sum = 0;
unsigned int idx_intercept_sum = 0;
unsigned int intercept_sum = 0;
unsigned int idx_recent_sum = 0;
@ -365,7 +386,7 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
int constraint_idx = 0;
int idx0 = 0, idx = -1;
bool alt_intercepts, alt_recent;
ktime_t delta_tick;
bool cpu_utilized;
s64 duration_ns;
int i;
@ -375,44 +396,48 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
}
cpu_data->time_span_ns = local_clock();
duration_ns = tick_nohz_get_sleep_length(&delta_tick);
cpu_data->sleep_length_ns = duration_ns;
/*
* Set the expected sleep length to infinity in case of an early
* return.
*/
cpu_data->sleep_length_ns = KTIME_MAX;
/* Check if there is any choice in the first place. */
if (drv->state_count < 2) {
idx = 0;
goto end;
}
if (!dev->states_usage[0].disable) {
idx = 0;
if (drv->states[1].target_residency_ns > duration_ns)
goto end;
goto out_tick;
}
cpu_data->utilized = teo_cpu_is_utilized(dev->cpu, cpu_data);
if (!dev->states_usage[0].disable)
idx = 0;
cpu_utilized = teo_cpu_is_utilized(dev->cpu, cpu_data);
/*
* If the CPU is being utilized over the threshold and there are only 2
* states to choose from, the metrics need not be considered, so choose
* the shallowest non-polling state and exit.
*/
if (drv->state_count < 3 && cpu_data->utilized) {
for (i = 0; i < drv->state_count; ++i) {
if (!dev->states_usage[i].disable &&
!(drv->states[i].flags & CPUIDLE_FLAG_POLLING)) {
idx = i;
goto end;
}
if (drv->state_count < 3 && cpu_utilized) {
/*
* If state 0 is enabled and it is not a polling one, select it
* right away unless the scheduler tick has been stopped, in
* which case care needs to be taken to leave the CPU in a deep
* enough state in case it is not woken up any time soon after
* all. If state 1 is disabled, though, state 0 must be used
* anyway.
*/
if ((!idx && !(drv->states[0].flags & CPUIDLE_FLAG_POLLING) &&
teo_state_ok(0, drv)) || dev->states_usage[1].disable) {
idx = 0;
goto out_tick;
}
/* Assume that state 1 is not a polling one and use it. */
idx = 1;
duration_ns = drv->states[1].target_residency_ns;
goto end;
}
/*
* Find the deepest idle state whose target residency does not exceed
* the current sleep length and the deepest idle state not deeper than
* the former whose exit latency does not exceed the current latency
* constraint. Compute the sums of metrics for early wakeup pattern
* detection.
*/
/* Compute the sums of metrics for early wakeup pattern detection. */
for (i = 1; i < drv->state_count; i++) {
struct teo_bin *prev_bin = &cpu_data->state_bins[i-1];
struct cpuidle_state *s = &drv->states[i];
@ -428,19 +453,15 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
if (dev->states_usage[i].disable)
continue;
if (idx < 0) {
idx = i; /* first enabled state */
idx0 = i;
}
if (s->target_residency_ns > duration_ns)
break;
if (idx < 0)
idx0 = i; /* first enabled state */
idx = i;
if (s->exit_latency_ns <= latency_req)
constraint_idx = i;
/* Save the sums for the current state. */
idx_intercept_sum = intercept_sum;
idx_hit_sum = hit_sum;
idx_recent_sum = recent_sum;
@ -449,11 +470,21 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
/* Avoid unnecessary overhead. */
if (idx < 0) {
idx = 0; /* No states enabled, must use 0. */
goto end;
} else if (idx == idx0) {
goto out_tick;
}
if (idx == idx0) {
/*
* Only one idle state is enabled, so use it, but do not
* allow the tick to be stopped it is shallow enough.
*/
duration_ns = drv->states[idx].target_residency_ns;
goto end;
}
tick_intercept_sum = intercept_sum +
cpu_data->state_bins[drv->state_count-1].intercepts;
/*
* If the sum of the intercepts metric for all of the idle states
* shallower than the current candidate one (idx) is greater than the
@ -461,13 +492,11 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
* all of the deeper states, or the sum of the numbers of recent
* intercepts over all of the states shallower than the candidate one
* is greater than a half of the number of recent events taken into
* account, the CPU is likely to wake up early, so find an alternative
* idle state to select.
* account, a shallower idle state is likely to be a better choice.
*/
alt_intercepts = 2 * idx_intercept_sum > cpu_data->total - idx_hit_sum;
alt_recent = idx_recent_sum > NR_RECENT / 2;
if (alt_recent || alt_intercepts) {
s64 first_suitable_span_ns = duration_ns;
int first_suitable_idx = idx;
/*
@ -476,44 +505,39 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
* cases (both with respect to intercepts overall and with
* respect to the recent intercepts only) in the past.
*
* Take the possible latency constraint and duration limitation
* present if the tick has been stopped already into account.
* Take the possible duration limitation present if the tick
* has been stopped already into account.
*/
intercept_sum = 0;
recent_sum = 0;
for (i = idx - 1; i >= 0; i--) {
struct teo_bin *bin = &cpu_data->state_bins[i];
s64 span_ns;
intercept_sum += bin->intercepts;
recent_sum += bin->recent;
span_ns = teo_middle_of_bin(i, drv);
if ((!alt_recent || 2 * recent_sum > idx_recent_sum) &&
(!alt_intercepts ||
2 * intercept_sum > idx_intercept_sum)) {
if (teo_time_ok(span_ns) &&
!dev->states_usage[i].disable) {
/*
* Use the current state unless it is too
* shallow or disabled, in which case take the
* first enabled state that is deep enough.
*/
if (teo_state_ok(i, drv) &&
!dev->states_usage[i].disable)
idx = i;
duration_ns = span_ns;
} else {
/*
* The current state is too shallow or
* disabled, so take the first enabled
* deeper state with suitable time span.
*/
else
idx = first_suitable_idx;
duration_ns = first_suitable_span_ns;
}
break;
}
if (dev->states_usage[i].disable)
continue;
if (!teo_time_ok(span_ns)) {
if (!teo_state_ok(i, drv)) {
/*
* The current state is too shallow, but if an
* alternative candidate state has been found,
@ -525,7 +549,6 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
break;
}
first_suitable_span_ns = span_ns;
first_suitable_idx = i;
}
}
@ -539,31 +562,75 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
/*
* If the CPU is being utilized over the threshold, choose a shallower
* non-polling state to improve latency
* non-polling state to improve latency, unless the scheduler tick has
* been stopped already and the shallower state's target residency is
* not sufficiently large.
*/
if (cpu_data->utilized)
idx = teo_find_shallower_state(drv, dev, idx, duration_ns, true);
if (cpu_utilized) {
i = teo_find_shallower_state(drv, dev, idx, KTIME_MAX, true);
if (teo_state_ok(i, drv))
idx = i;
}
/*
* Skip the timers check if state 0 is the current candidate one,
* because an immediate non-timer wakeup is expected in that case.
*/
if (!idx)
goto out_tick;
/*
* If state 0 is a polling one, check if the target residency of
* the current candidate state is low enough and skip the timers
* check in that case too.
*/
if ((drv->states[0].flags & CPUIDLE_FLAG_POLLING) &&
drv->states[idx].target_residency_ns < RESIDENCY_THRESHOLD_NS)
goto out_tick;
duration_ns = tick_nohz_get_sleep_length(&delta_tick);
cpu_data->sleep_length_ns = duration_ns;
/*
* If the closest expected timer is before the terget residency of the
* candidate state, a shallower one needs to be found.
*/
if (drv->states[idx].target_residency_ns > duration_ns) {
i = teo_find_shallower_state(drv, dev, idx, duration_ns, false);
if (teo_state_ok(i, drv))
idx = i;
}
/*
* If the selected state's target residency is below the tick length
* and intercepts occurring before the tick length are the majority of
* total wakeup events, do not stop the tick.
*/
if (drv->states[idx].target_residency_ns < TICK_NSEC &&
tick_intercept_sum > cpu_data->total / 2 + cpu_data->total / 8)
duration_ns = TICK_NSEC / 2;
end:
/*
* Don't stop the tick if the selected state is a polling one or if the
* expected idle duration is shorter than the tick period length.
* Allow the tick to be stopped unless the selected state is a polling
* one or the expected idle duration is shorter than the tick period
* length.
*/
if (((drv->states[idx].flags & CPUIDLE_FLAG_POLLING) ||
duration_ns < TICK_NSEC) && !tick_nohz_tick_stopped()) {
*stop_tick = false;
if ((!(drv->states[idx].flags & CPUIDLE_FLAG_POLLING) &&
duration_ns >= TICK_NSEC) || tick_nohz_tick_stopped())
return idx;
/*
* The tick is not going to be stopped, so if the target
* residency of the state to be returned is not within the time
* till the closest timer including the tick, try to correct
* that.
*/
if (idx > idx0 &&
drv->states[idx].target_residency_ns > delta_tick)
idx = teo_find_shallower_state(drv, dev, idx, delta_tick, false);
}
/*
* The tick is not going to be stopped, so if the target residency of
* the state to be returned is not within the time till the closest
* timer including the tick, try to correct that.
*/
if (idx > idx0 &&
drv->states[idx].target_residency_ns > delta_tick)
idx = teo_find_shallower_state(drv, dev, idx, delta_tick, false);
out_tick:
*stop_tick = false;
return idx;
}

14
include/linux/cpufreq.h
View file

@ -19,6 +19,7 @@
#include <linux/pm_qos.h>
#include <linux/spinlock.h>
#include <linux/sysfs.h>
#include <linux/minmax.h>
/*********************************************************************
* CPUFREQ INTERFACE *
@ -467,17 +468,8 @@ static inline void cpufreq_verify_within_limits(struct cpufreq_policy_data *poli
unsigned int min,
unsigned int max)
{
if (policy->min < min)
policy->min = min;
if (policy->max < min)
policy->max = min;
if (policy->min > max)
policy->min = max;
if (policy->max > max)
policy->max = max;
if (policy->min > policy->max)
policy->min = policy->max;
return;
policy->max = clamp(policy->max, min, max);
policy->min = clamp(policy->min, min, policy->max);
}
static inline void