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-rw-r--r--drivers/cpuidle/governors/menu.c25
-rw-r--r--include/linux/sched/stat.h1
-rw-r--r--kernel/hung_task.c30
-rw-r--r--kernel/sched/core.c34
4 files changed, 48 insertions, 42 deletions
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 575a68f31761..76df4f947f07 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -134,11 +134,6 @@ struct menu_device {
#define LOAD_INT(x) ((x) >> FSHIFT)
#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
-static inline int get_loadavg(unsigned long load)
-{
- return LOAD_INT(load) * 10 + LOAD_FRAC(load) / 10;
-}
-
static inline int which_bucket(unsigned int duration, unsigned long nr_iowaiters)
{
int bucket = 0;
@@ -172,18 +167,10 @@ static inline int which_bucket(unsigned int duration, unsigned long nr_iowaiters
* to be, the higher this multiplier, and thus the higher
* the barrier to go to an expensive C state.
*/
-static inline int performance_multiplier(unsigned long nr_iowaiters, unsigned long load)
+static inline int performance_multiplier(unsigned long nr_iowaiters)
{
- int mult = 1;
-
- /* for higher loadavg, we are more reluctant */
-
- mult += 2 * get_loadavg(load);
-
- /* for IO wait tasks (per cpu!) we add 5x each */
- mult += 10 * nr_iowaiters;
-
- return mult;
+ /* for IO wait tasks (per cpu!) we add 10x each */
+ return 1 + 10 * nr_iowaiters;
}
static DEFINE_PER_CPU(struct menu_device, menu_devices);
@@ -301,7 +288,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
int idx;
unsigned int interactivity_req;
unsigned int predicted_us;
- unsigned long nr_iowaiters, cpu_load;
+ unsigned long nr_iowaiters;
ktime_t delta_next;
if (data->needs_update) {
@@ -312,7 +299,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
/* determine the expected residency time, round up */
data->next_timer_us = ktime_to_us(tick_nohz_get_sleep_length(&delta_next));
- get_iowait_load(&nr_iowaiters, &cpu_load);
+ nr_iowaiters = nr_iowait_cpu(dev->cpu);
data->bucket = which_bucket(data->next_timer_us, nr_iowaiters);
if (unlikely(drv->state_count <= 1 || latency_req == 0) ||
@@ -356,7 +343,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
* Use the performance multiplier and the user-configurable
* latency_req to determine the maximum exit latency.
*/
- interactivity_req = predicted_us / performance_multiplier(nr_iowaiters, cpu_load);
+ interactivity_req = predicted_us / performance_multiplier(nr_iowaiters);
if (latency_req > interactivity_req)
latency_req = interactivity_req;
}
diff --git a/include/linux/sched/stat.h b/include/linux/sched/stat.h
index 04f1321d14c4..f30954cc059d 100644
--- a/include/linux/sched/stat.h
+++ b/include/linux/sched/stat.h
@@ -20,7 +20,6 @@ extern unsigned long nr_running(void);
extern bool single_task_running(void);
extern unsigned long nr_iowait(void);
extern unsigned long nr_iowait_cpu(int cpu);
-extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
static inline int sched_info_on(void)
{
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index b9132d1269ef..cb8e3e8ac7b9 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -15,6 +15,7 @@
#include <linux/lockdep.h>
#include <linux/export.h>
#include <linux/sysctl.h>
+#include <linux/suspend.h>
#include <linux/utsname.h>
#include <linux/sched/signal.h>
#include <linux/sched/debug.h>
@@ -242,6 +243,28 @@ void reset_hung_task_detector(void)
}
EXPORT_SYMBOL_GPL(reset_hung_task_detector);
+static bool hung_detector_suspended;
+
+static int hungtask_pm_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ switch (action) {
+ case PM_SUSPEND_PREPARE:
+ case PM_HIBERNATION_PREPARE:
+ case PM_RESTORE_PREPARE:
+ hung_detector_suspended = true;
+ break;
+ case PM_POST_SUSPEND:
+ case PM_POST_HIBERNATION:
+ case PM_POST_RESTORE:
+ hung_detector_suspended = false;
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
+
/*
* kthread which checks for tasks stuck in D state
*/
@@ -261,7 +284,8 @@ static int watchdog(void *dummy)
interval = min_t(unsigned long, interval, timeout);
t = hung_timeout_jiffies(hung_last_checked, interval);
if (t <= 0) {
- if (!atomic_xchg(&reset_hung_task, 0))
+ if (!atomic_xchg(&reset_hung_task, 0) &&
+ !hung_detector_suspended)
check_hung_uninterruptible_tasks(timeout);
hung_last_checked = jiffies;
continue;
@@ -275,6 +299,10 @@ static int watchdog(void *dummy)
static int __init hung_task_init(void)
{
atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
+
+ /* Disable hung task detector on suspend */
+ pm_notifier(hungtask_pm_notify, 0);
+
watchdog_task = kthread_run(watchdog, NULL, "khungtaskd");
return 0;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index fe0223121883..c8d5c279be14 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2876,6 +2876,18 @@ unsigned long long nr_context_switches(void)
}
/*
+ * Consumers of these two interfaces, like for example the cpuidle menu
+ * governor, are using nonsensical data. Preferring shallow idle state selection
+ * for a CPU that has IO-wait which might not even end up running the task when
+ * it does become runnable.
+ */
+
+unsigned long nr_iowait_cpu(int cpu)
+{
+ return atomic_read(&cpu_rq(cpu)->nr_iowait);
+}
+
+/*
* IO-wait accounting, and how its mostly bollocks (on SMP).
*
* The idea behind IO-wait account is to account the idle time that we could
@@ -2910,31 +2922,11 @@ unsigned long nr_iowait(void)
unsigned long i, sum = 0;
for_each_possible_cpu(i)
- sum += atomic_read(&cpu_rq(i)->nr_iowait);
+ sum += nr_iowait_cpu(i);
return sum;
}
-/*
- * Consumers of these two interfaces, like for example the cpuidle menu
- * governor, are using nonsensical data. Preferring shallow idle state selection
- * for a CPU that has IO-wait which might not even end up running the task when
- * it does become runnable.
- */
-
-unsigned long nr_iowait_cpu(int cpu)
-{
- struct rq *this = cpu_rq(cpu);
- return atomic_read(&this->nr_iowait);
-}
-
-void get_iowait_load(unsigned long *nr_waiters, unsigned long *load)
-{
- struct rq *rq = this_rq();
- *nr_waiters = atomic_read(&rq->nr_iowait);
- *load = rq->load.weight;
-}
-
#ifdef CONFIG_SMP
/*