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-rw-r--r--MAINTAINERS3
-rw-r--r--drivers/cpuidle/cpuidle-powernv.c2
-rw-r--r--drivers/cpuidle/cpuidle.c13
-rw-r--r--drivers/cpuidle/dt_idle_states.c6
-rw-r--r--drivers/cpuidle/governor.c4
-rw-r--r--drivers/cpuidle/governors/ladder.c2
-rw-r--r--drivers/cpuidle/governors/menu.c2
-rw-r--r--include/linux/cpu.h2
-rw-r--r--include/linux/cpuidle.h9
-rw-r--r--include/linux/sched.h3
-rw-r--r--kernel/fork.c2
-rw-r--r--kernel/sched/core.c1
-rw-r--r--kernel/sched/idle.c175
13 files changed, 143 insertions, 81 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index 8d4148406923..3c7348536c56 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3380,6 +3380,7 @@ M: Daniel Lezcano <daniel.lezcano@linaro.org>
L: linux-pm@vger.kernel.org
S: Maintained
T: git git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git
+B: https://bugzilla.kernel.org
F: drivers/cpuidle/*
F: include/linux/cpuidle.h
@@ -6289,9 +6290,11 @@ S: Maintained
F: drivers/platform/x86/intel-vbtn.c
INTEL IDLE DRIVER
+M: Jacob Pan <jacob.jun.pan@linux.intel.com>
M: Len Brown <lenb@kernel.org>
L: linux-pm@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux.git
+B: https://bugzilla.kernel.org
S: Supported
F: drivers/idle/intel_idle.c
diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c
index 7fe442ca38f4..0835a37a5f3a 100644
--- a/drivers/cpuidle/cpuidle-powernv.c
+++ b/drivers/cpuidle/cpuidle-powernv.c
@@ -22,7 +22,7 @@
#define POWERNV_THRESHOLD_LATENCY_NS 200000
-struct cpuidle_driver powernv_idle_driver = {
+static struct cpuidle_driver powernv_idle_driver = {
.name = "powernv_idle",
.owner = THIS_MODULE,
};
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index c73207abb5a4..afc005b917fe 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -97,7 +97,17 @@ static int find_deepest_state(struct cpuidle_driver *drv,
return ret;
}
-#ifdef CONFIG_SUSPEND
+/* Set the current cpu to use the deepest idle state, override governors */
+void cpuidle_use_deepest_state(bool enable)
+{
+ struct cpuidle_device *dev;
+
+ preempt_disable();
+ dev = cpuidle_get_device();
+ dev->use_deepest_state = enable;
+ preempt_enable();
+}
+
/**
* cpuidle_find_deepest_state - Find the deepest available idle state.
* @drv: cpuidle driver for the given CPU.
@@ -109,6 +119,7 @@ int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
return find_deepest_state(drv, dev, UINT_MAX, 0, false);
}
+#ifdef CONFIG_SUSPEND
static void enter_freeze_proper(struct cpuidle_driver *drv,
struct cpuidle_device *dev, int index)
{
diff --git a/drivers/cpuidle/dt_idle_states.c b/drivers/cpuidle/dt_idle_states.c
index a5c111b67f37..ffca4fc0061d 100644
--- a/drivers/cpuidle/dt_idle_states.c
+++ b/drivers/cpuidle/dt_idle_states.c
@@ -38,6 +38,12 @@ static int init_state_node(struct cpuidle_state *idle_state,
* state enter function.
*/
idle_state->enter = match_id->data;
+ /*
+ * Since this is not a "coupled" state, it's safe to assume interrupts
+ * won't be enabled when it exits allowing the tick to be frozen
+ * safely. So enter() can be also enter_freeze() callback.
+ */
+ idle_state->enter_freeze = match_id->data;
err = of_property_read_u32(state_node, "wakeup-latency-us",
&idle_state->exit_latency);
diff --git a/drivers/cpuidle/governor.c b/drivers/cpuidle/governor.c
index fb9f511cca23..4e78263e34a4 100644
--- a/drivers/cpuidle/governor.c
+++ b/drivers/cpuidle/governor.c
@@ -9,7 +9,6 @@
*/
#include <linux/mutex.h>
-#include <linux/module.h>
#include <linux/cpuidle.h>
#include "cpuidle.h"
@@ -53,14 +52,11 @@ int cpuidle_switch_governor(struct cpuidle_governor *gov)
if (cpuidle_curr_governor) {
list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
cpuidle_disable_device(dev);
- module_put(cpuidle_curr_governor->owner);
}
cpuidle_curr_governor = gov;
if (gov) {
- if (!try_module_get(cpuidle_curr_governor->owner))
- return -EINVAL;
list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
cpuidle_enable_device(dev);
cpuidle_install_idle_handler();
diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c
index 63bd5a403e22..fe8f08948fcb 100644
--- a/drivers/cpuidle/governors/ladder.c
+++ b/drivers/cpuidle/governors/ladder.c
@@ -15,7 +15,6 @@
#include <linux/kernel.h>
#include <linux/cpuidle.h>
#include <linux/pm_qos.h>
-#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/tick.h>
@@ -177,7 +176,6 @@ static struct cpuidle_governor ladder_governor = {
.enable = ladder_enable_device,
.select = ladder_select_state,
.reflect = ladder_reflect,
- .owner = THIS_MODULE,
};
/**
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 03d38c291de6..d9b5b9398a0f 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -19,7 +19,6 @@
#include <linux/tick.h>
#include <linux/sched.h>
#include <linux/math64.h>
-#include <linux/module.h>
/*
* Please note when changing the tuning values:
@@ -484,7 +483,6 @@ static struct cpuidle_governor menu_governor = {
.enable = menu_enable_device,
.select = menu_select,
.reflect = menu_reflect,
- .owner = THIS_MODULE,
};
/**
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index b886dc17f2f3..ac0efae38072 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -245,6 +245,8 @@ void arch_cpu_idle_dead(void);
int cpu_report_state(int cpu);
int cpu_check_up_prepare(int cpu);
void cpu_set_state_online(int cpu);
+void play_idle(unsigned long duration_ms);
+
#ifdef CONFIG_HOTPLUG_CPU
bool cpu_wait_death(unsigned int cpu, int seconds);
bool cpu_report_death(void);
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index bb31373c3478..da346f2817a8 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -74,6 +74,7 @@ struct cpuidle_driver_kobj;
struct cpuidle_device {
unsigned int registered:1;
unsigned int enabled:1;
+ unsigned int use_deepest_state:1;
unsigned int cpu;
int last_residency;
@@ -192,11 +193,12 @@ static inline struct cpuidle_driver *cpuidle_get_cpu_driver(
static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; }
#endif
-#if defined(CONFIG_CPU_IDLE) && defined(CONFIG_SUSPEND)
+#ifdef CONFIG_CPU_IDLE
extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
struct cpuidle_device *dev);
extern int cpuidle_enter_freeze(struct cpuidle_driver *drv,
struct cpuidle_device *dev);
+extern void cpuidle_use_deepest_state(bool enable);
#else
static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
struct cpuidle_device *dev)
@@ -204,6 +206,9 @@ static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
static inline int cpuidle_enter_freeze(struct cpuidle_driver *drv,
struct cpuidle_device *dev)
{return -ENODEV; }
+static inline void cpuidle_use_deepest_state(bool enable)
+{
+}
#endif
/* kernel/sched/idle.c */
@@ -235,8 +240,6 @@ struct cpuidle_governor {
int (*select) (struct cpuidle_driver *drv,
struct cpuidle_device *dev);
void (*reflect) (struct cpuidle_device *dev, int index);
-
- struct module *owner;
};
#ifdef CONFIG_CPU_IDLE
diff --git a/include/linux/sched.h b/include/linux/sched.h
index e9c009dc3a4a..a3d338e15b17 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2254,6 +2254,7 @@ extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut,
/*
* Per process flags
*/
+#define PF_IDLE 0x00000002 /* I am an IDLE thread */
#define PF_EXITING 0x00000004 /* getting shut down */
#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
@@ -2611,7 +2612,7 @@ extern struct task_struct *idle_task(int cpu);
*/
static inline bool is_idle_task(const struct task_struct *p)
{
- return p->pid == 0;
+ return !!(p->flags & PF_IDLE);
}
extern struct task_struct *curr_task(int cpu);
extern void ia64_set_curr_task(int cpu, struct task_struct *p);
diff --git a/kernel/fork.c b/kernel/fork.c
index 997ac1d584f7..a8eb821d1d4b 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1540,7 +1540,7 @@ static __latent_entropy struct task_struct *copy_process(
goto bad_fork_cleanup_count;
delayacct_tsk_init(p); /* Must remain after dup_task_struct() */
- p->flags &= ~(PF_SUPERPRIV | PF_WQ_WORKER);
+ p->flags &= ~(PF_SUPERPRIV | PF_WQ_WORKER | PF_IDLE);
p->flags |= PF_FORKNOEXEC;
INIT_LIST_HEAD(&p->children);
INIT_LIST_HEAD(&p->sibling);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 154fd689fe02..c95fbcd9fe1f 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5279,6 +5279,7 @@ void init_idle(struct task_struct *idle, int cpu)
__sched_fork(0, idle);
idle->state = TASK_RUNNING;
idle->se.exec_start = sched_clock();
+ idle->flags |= PF_IDLE;
kasan_unpoison_task_stack(idle);
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 1d8718d5300d..6a4bae0a649d 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -164,11 +164,14 @@ static void cpuidle_idle_call(void)
* timekeeping to prevent timer interrupts from kicking us out of idle
* until a proper wakeup interrupt happens.
*/
- if (idle_should_freeze()) {
- entered_state = cpuidle_enter_freeze(drv, dev);
- if (entered_state > 0) {
- local_irq_enable();
- goto exit_idle;
+
+ if (idle_should_freeze() || dev->use_deepest_state) {
+ if (idle_should_freeze()) {
+ entered_state = cpuidle_enter_freeze(drv, dev);
+ if (entered_state > 0) {
+ local_irq_enable();
+ goto exit_idle;
+ }
}
next_state = cpuidle_find_deepest_state(drv, dev);
@@ -202,76 +205,65 @@ exit_idle:
*
* Called with polling cleared.
*/
-static void cpu_idle_loop(void)
+static void do_idle(void)
{
- int cpu = smp_processor_id();
-
- while (1) {
- /*
- * If the arch has a polling bit, we maintain an invariant:
- *
- * Our polling bit is clear if we're not scheduled (i.e. if
- * rq->curr != rq->idle). This means that, if rq->idle has
- * the polling bit set, then setting need_resched is
- * guaranteed to cause the cpu to reschedule.
- */
-
- __current_set_polling();
- quiet_vmstat();
- tick_nohz_idle_enter();
+ /*
+ * If the arch has a polling bit, we maintain an invariant:
+ *
+ * Our polling bit is clear if we're not scheduled (i.e. if rq->curr !=
+ * rq->idle). This means that, if rq->idle has the polling bit set,
+ * then setting need_resched is guaranteed to cause the CPU to
+ * reschedule.
+ */
- while (!need_resched()) {
- check_pgt_cache();
- rmb();
+ __current_set_polling();
+ tick_nohz_idle_enter();
- if (cpu_is_offline(cpu)) {
- cpuhp_report_idle_dead();
- arch_cpu_idle_dead();
- }
+ while (!need_resched()) {
+ check_pgt_cache();
+ rmb();
- local_irq_disable();
- arch_cpu_idle_enter();
-
- /*
- * In poll mode we reenable interrupts and spin.
- *
- * Also if we detected in the wakeup from idle
- * path that the tick broadcast device expired
- * for us, we don't want to go deep idle as we
- * know that the IPI is going to arrive right
- * away
- */
- if (cpu_idle_force_poll || tick_check_broadcast_expired())
- cpu_idle_poll();
- else
- cpuidle_idle_call();
-
- arch_cpu_idle_exit();
+ if (cpu_is_offline(smp_processor_id())) {
+ cpuhp_report_idle_dead();
+ arch_cpu_idle_dead();
}
- /*
- * Since we fell out of the loop above, we know
- * TIF_NEED_RESCHED must be set, propagate it into
- * PREEMPT_NEED_RESCHED.
- *
- * This is required because for polling idle loops we will
- * not have had an IPI to fold the state for us.
- */
- preempt_set_need_resched();
- tick_nohz_idle_exit();
- __current_clr_polling();
+ local_irq_disable();
+ arch_cpu_idle_enter();
/*
- * We promise to call sched_ttwu_pending and reschedule
- * if need_resched is set while polling is set. That
- * means that clearing polling needs to be visible
- * before doing these things.
+ * In poll mode we reenable interrupts and spin. Also if we
+ * detected in the wakeup from idle path that the tick
+ * broadcast device expired for us, we don't want to go deep
+ * idle as we know that the IPI is going to arrive right away.
*/
- smp_mb__after_atomic();
-
- sched_ttwu_pending();
- schedule_preempt_disabled();
+ if (cpu_idle_force_poll || tick_check_broadcast_expired())
+ cpu_idle_poll();
+ else
+ cpuidle_idle_call();
+ arch_cpu_idle_exit();
}
+
+ /*
+ * Since we fell out of the loop above, we know TIF_NEED_RESCHED must
+ * be set, propagate it into PREEMPT_NEED_RESCHED.
+ *
+ * This is required because for polling idle loops we will not have had
+ * an IPI to fold the state for us.
+ */
+ preempt_set_need_resched();
+ tick_nohz_idle_exit();
+ __current_clr_polling();
+
+ /*
+ * We promise to call sched_ttwu_pending() and reschedule if
+ * need_resched() is set while polling is set. That means that clearing
+ * polling needs to be visible before doing these things.
+ */
+ smp_mb__after_atomic();
+
+ sched_ttwu_pending();
+ schedule_preempt_disabled();
}
bool cpu_in_idle(unsigned long pc)
@@ -280,6 +272,56 @@ bool cpu_in_idle(unsigned long pc)
pc < (unsigned long)__cpuidle_text_end;
}
+struct idle_timer {
+ struct hrtimer timer;
+ int done;
+};
+
+static enum hrtimer_restart idle_inject_timer_fn(struct hrtimer *timer)
+{
+ struct idle_timer *it = container_of(timer, struct idle_timer, timer);
+
+ WRITE_ONCE(it->done, 1);
+ set_tsk_need_resched(current);
+
+ return HRTIMER_NORESTART;
+}
+
+void play_idle(unsigned long duration_ms)
+{
+ struct idle_timer it;
+
+ /*
+ * Only FIFO tasks can disable the tick since they don't need the forced
+ * preemption.
+ */
+ WARN_ON_ONCE(current->policy != SCHED_FIFO);
+ WARN_ON_ONCE(current->nr_cpus_allowed != 1);
+ WARN_ON_ONCE(!(current->flags & PF_KTHREAD));
+ WARN_ON_ONCE(!(current->flags & PF_NO_SETAFFINITY));
+ WARN_ON_ONCE(!duration_ms);
+
+ rcu_sleep_check();
+ preempt_disable();
+ current->flags |= PF_IDLE;
+ cpuidle_use_deepest_state(true);
+
+ it.done = 0;
+ hrtimer_init_on_stack(&it.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ it.timer.function = idle_inject_timer_fn;
+ hrtimer_start(&it.timer, ms_to_ktime(duration_ms), HRTIMER_MODE_REL_PINNED);
+
+ while (!READ_ONCE(it.done))
+ do_idle();
+
+ cpuidle_use_deepest_state(false);
+ current->flags &= ~PF_IDLE;
+
+ preempt_fold_need_resched();
+ preempt_enable();
+}
+EXPORT_SYMBOL_GPL(play_idle);
+
void cpu_startup_entry(enum cpuhp_state state)
{
/*
@@ -299,5 +341,6 @@ void cpu_startup_entry(enum cpuhp_state state)
#endif
arch_cpu_idle_prepare();
cpuhp_online_idle(state);
- cpu_idle_loop();
+ while (1)
+ do_idle();
}