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-rw-r--r--kernel/drivers/base/power/domain.c830
1 files changed, 208 insertions, 622 deletions
diff --git a/kernel/drivers/base/power/domain.c b/kernel/drivers/base/power/domain.c
index 2327613d4..65f50eccd 100644
--- a/kernel/drivers/base/power/domain.c
+++ b/kernel/drivers/base/power/domain.c
@@ -6,6 +6,7 @@
* This file is released under the GPLv2.
*/
+#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/platform_device.h>
@@ -19,6 +20,8 @@
#include <linux/suspend.h>
#include <linux/export.h>
+#define GENPD_RETRY_MAX_MS 250 /* Approximate */
+
#define GENPD_DEV_CALLBACK(genpd, type, callback, dev) \
({ \
type (*__routine)(struct device *__d); \
@@ -31,43 +34,9 @@
__ret; \
})
-#define GENPD_DEV_TIMED_CALLBACK(genpd, type, callback, dev, field, name) \
-({ \
- ktime_t __start = ktime_get(); \
- type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev); \
- s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start)); \
- struct gpd_timing_data *__td = &dev_gpd_data(dev)->td; \
- if (!__retval && __elapsed > __td->field) { \
- __td->field = __elapsed; \
- dev_dbg(dev, name " latency exceeded, new value %lld ns\n", \
- __elapsed); \
- genpd->max_off_time_changed = true; \
- __td->constraint_changed = true; \
- } \
- __retval; \
-})
-
static LIST_HEAD(gpd_list);
static DEFINE_MUTEX(gpd_list_lock);
-static struct generic_pm_domain *pm_genpd_lookup_name(const char *domain_name)
-{
- struct generic_pm_domain *genpd = NULL, *gpd;
-
- if (IS_ERR_OR_NULL(domain_name))
- return NULL;
-
- mutex_lock(&gpd_list_lock);
- list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
- if (!strcmp(gpd->name, domain_name)) {
- genpd = gpd;
- break;
- }
- }
- mutex_unlock(&gpd_list_lock);
- return genpd;
-}
-
/*
* Get the generic PM domain for a particular struct device.
* This validates the struct device pointer, the PM domain pointer,
@@ -107,14 +76,12 @@ static struct generic_pm_domain *dev_to_genpd(struct device *dev)
static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
{
- return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev,
- stop_latency_ns, "stop");
+ return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
}
static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev)
{
- return GENPD_DEV_TIMED_CALLBACK(genpd, int, start, dev,
- start_latency_ns, "start");
+ return GENPD_DEV_CALLBACK(genpd, int, start, dev);
}
static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
@@ -133,55 +100,7 @@ static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
smp_mb__after_atomic();
}
-static void genpd_acquire_lock(struct generic_pm_domain *genpd)
-{
- DEFINE_WAIT(wait);
-
- mutex_lock(&genpd->lock);
- /*
- * Wait for the domain to transition into either the active,
- * or the power off state.
- */
- for (;;) {
- prepare_to_wait(&genpd->status_wait_queue, &wait,
- TASK_UNINTERRUPTIBLE);
- if (genpd->status == GPD_STATE_ACTIVE
- || genpd->status == GPD_STATE_POWER_OFF)
- break;
- mutex_unlock(&genpd->lock);
-
- schedule();
-
- mutex_lock(&genpd->lock);
- }
- finish_wait(&genpd->status_wait_queue, &wait);
-}
-
-static void genpd_release_lock(struct generic_pm_domain *genpd)
-{
- mutex_unlock(&genpd->lock);
-}
-
-static void genpd_set_active(struct generic_pm_domain *genpd)
-{
- if (genpd->resume_count == 0)
- genpd->status = GPD_STATE_ACTIVE;
-}
-
-static void genpd_recalc_cpu_exit_latency(struct generic_pm_domain *genpd)
-{
- s64 usecs64;
-
- if (!genpd->cpuidle_data)
- return;
-
- usecs64 = genpd->power_on_latency_ns;
- do_div(usecs64, NSEC_PER_USEC);
- usecs64 += genpd->cpuidle_data->saved_exit_latency;
- genpd->cpuidle_data->idle_state->exit_latency = usecs64;
-}
-
-static int genpd_power_on(struct generic_pm_domain *genpd)
+static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
{
ktime_t time_start;
s64 elapsed_ns;
@@ -190,6 +109,9 @@ static int genpd_power_on(struct generic_pm_domain *genpd)
if (!genpd->power_on)
return 0;
+ if (!timed)
+ return genpd->power_on(genpd);
+
time_start = ktime_get();
ret = genpd->power_on(genpd);
if (ret)
@@ -201,14 +123,13 @@ static int genpd_power_on(struct generic_pm_domain *genpd)
genpd->power_on_latency_ns = elapsed_ns;
genpd->max_off_time_changed = true;
- genpd_recalc_cpu_exit_latency(genpd);
pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
genpd->name, "on", elapsed_ns);
return ret;
}
-static int genpd_power_off(struct generic_pm_domain *genpd)
+static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
{
ktime_t time_start;
s64 elapsed_ns;
@@ -217,6 +138,9 @@ static int genpd_power_off(struct generic_pm_domain *genpd)
if (!genpd->power_off)
return 0;
+ if (!timed)
+ return genpd->power_off(genpd);
+
time_start = ktime_get();
ret = genpd->power_off(genpd);
if (ret == -EBUSY)
@@ -235,49 +159,35 @@ static int genpd_power_off(struct generic_pm_domain *genpd)
}
/**
- * __pm_genpd_poweron - Restore power to a given PM domain and its masters.
+ * genpd_queue_power_off_work - Queue up the execution of genpd_poweroff().
+ * @genpd: PM domait to power off.
+ *
+ * Queue up the execution of genpd_poweroff() unless it's already been done
+ * before.
+ */
+static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
+{
+ queue_work(pm_wq, &genpd->power_off_work);
+}
+
+static int genpd_poweron(struct generic_pm_domain *genpd);
+
+/**
+ * __genpd_poweron - Restore power to a given PM domain and its masters.
* @genpd: PM domain to power up.
*
* Restore power to @genpd and all of its masters so that it is possible to
* resume a device belonging to it.
*/
-static int __pm_genpd_poweron(struct generic_pm_domain *genpd)
- __releases(&genpd->lock) __acquires(&genpd->lock)
+static int __genpd_poweron(struct generic_pm_domain *genpd)
{
struct gpd_link *link;
- DEFINE_WAIT(wait);
int ret = 0;
- /* If the domain's master is being waited for, we have to wait too. */
- for (;;) {
- prepare_to_wait(&genpd->status_wait_queue, &wait,
- TASK_UNINTERRUPTIBLE);
- if (genpd->status != GPD_STATE_WAIT_MASTER)
- break;
- mutex_unlock(&genpd->lock);
-
- schedule();
-
- mutex_lock(&genpd->lock);
- }
- finish_wait(&genpd->status_wait_queue, &wait);
-
if (genpd->status == GPD_STATE_ACTIVE
|| (genpd->prepared_count > 0 && genpd->suspend_power_off))
return 0;
- if (genpd->status != GPD_STATE_POWER_OFF) {
- genpd_set_active(genpd);
- return 0;
- }
-
- if (genpd->cpuidle_data) {
- cpuidle_pause_and_lock();
- genpd->cpuidle_data->idle_state->disabled = true;
- cpuidle_resume_and_unlock();
- goto out;
- }
-
/*
* The list is guaranteed not to change while the loop below is being
* executed, unless one of the masters' .power_on() callbacks fiddles
@@ -285,85 +195,55 @@ static int __pm_genpd_poweron(struct generic_pm_domain *genpd)
*/
list_for_each_entry(link, &genpd->slave_links, slave_node) {
genpd_sd_counter_inc(link->master);
- genpd->status = GPD_STATE_WAIT_MASTER;
- mutex_unlock(&genpd->lock);
-
- ret = pm_genpd_poweron(link->master);
-
- mutex_lock(&genpd->lock);
-
- /*
- * The "wait for parent" status is guaranteed not to change
- * while the master is powering on.
- */
- genpd->status = GPD_STATE_POWER_OFF;
- wake_up_all(&genpd->status_wait_queue);
+ ret = genpd_poweron(link->master);
if (ret) {
genpd_sd_counter_dec(link->master);
goto err;
}
}
- ret = genpd_power_on(genpd);
+ ret = genpd_power_on(genpd, true);
if (ret)
goto err;
- out:
- genpd_set_active(genpd);
-
+ genpd->status = GPD_STATE_ACTIVE;
return 0;
err:
- list_for_each_entry_continue_reverse(link, &genpd->slave_links, slave_node)
+ list_for_each_entry_continue_reverse(link,
+ &genpd->slave_links,
+ slave_node) {
genpd_sd_counter_dec(link->master);
+ genpd_queue_power_off_work(link->master);
+ }
return ret;
}
/**
- * pm_genpd_poweron - Restore power to a given PM domain and its masters.
+ * genpd_poweron - Restore power to a given PM domain and its masters.
* @genpd: PM domain to power up.
*/
-int pm_genpd_poweron(struct generic_pm_domain *genpd)
+static int genpd_poweron(struct generic_pm_domain *genpd)
{
int ret;
mutex_lock(&genpd->lock);
- ret = __pm_genpd_poweron(genpd);
+ ret = __genpd_poweron(genpd);
mutex_unlock(&genpd->lock);
return ret;
}
-/**
- * pm_genpd_name_poweron - Restore power to a given PM domain and its masters.
- * @domain_name: Name of the PM domain to power up.
- */
-int pm_genpd_name_poweron(const char *domain_name)
-{
- struct generic_pm_domain *genpd;
-
- genpd = pm_genpd_lookup_name(domain_name);
- return genpd ? pm_genpd_poweron(genpd) : -EINVAL;
-}
-
-static int genpd_start_dev_no_timing(struct generic_pm_domain *genpd,
- struct device *dev)
-{
- return GENPD_DEV_CALLBACK(genpd, int, start, dev);
-}
-
static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
{
- return GENPD_DEV_TIMED_CALLBACK(genpd, int, save_state, dev,
- save_state_latency_ns, "state save");
+ return GENPD_DEV_CALLBACK(genpd, int, save_state, dev);
}
-static int genpd_restore_dev(struct generic_pm_domain *genpd, struct device *dev)
+static int genpd_restore_dev(struct generic_pm_domain *genpd,
+ struct device *dev)
{
- return GENPD_DEV_TIMED_CALLBACK(genpd, int, restore_state, dev,
- restore_state_latency_ns,
- "state restore");
+ return GENPD_DEV_CALLBACK(genpd, int, restore_state, dev);
}
static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
@@ -407,133 +287,31 @@ static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
}
/**
- * __pm_genpd_save_device - Save the pre-suspend state of a device.
- * @pdd: Domain data of the device to save the state of.
- * @genpd: PM domain the device belongs to.
- */
-static int __pm_genpd_save_device(struct pm_domain_data *pdd,
- struct generic_pm_domain *genpd)
- __releases(&genpd->lock) __acquires(&genpd->lock)
-{
- struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
- struct device *dev = pdd->dev;
- int ret = 0;
-
- if (gpd_data->need_restore > 0)
- return 0;
-
- /*
- * If the value of the need_restore flag is still unknown at this point,
- * we trust that pm_genpd_poweroff() has verified that the device is
- * already runtime PM suspended.
- */
- if (gpd_data->need_restore < 0) {
- gpd_data->need_restore = 1;
- return 0;
- }
-
- mutex_unlock(&genpd->lock);
-
- genpd_start_dev(genpd, dev);
- ret = genpd_save_dev(genpd, dev);
- genpd_stop_dev(genpd, dev);
-
- mutex_lock(&genpd->lock);
-
- if (!ret)
- gpd_data->need_restore = 1;
-
- return ret;
-}
-
-/**
- * __pm_genpd_restore_device - Restore the pre-suspend state of a device.
- * @pdd: Domain data of the device to restore the state of.
- * @genpd: PM domain the device belongs to.
- */
-static void __pm_genpd_restore_device(struct pm_domain_data *pdd,
- struct generic_pm_domain *genpd)
- __releases(&genpd->lock) __acquires(&genpd->lock)
-{
- struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
- struct device *dev = pdd->dev;
- int need_restore = gpd_data->need_restore;
-
- gpd_data->need_restore = 0;
- mutex_unlock(&genpd->lock);
-
- genpd_start_dev(genpd, dev);
-
- /*
- * Call genpd_restore_dev() for recently added devices too (need_restore
- * is negative then).
- */
- if (need_restore)
- genpd_restore_dev(genpd, dev);
-
- mutex_lock(&genpd->lock);
-}
-
-/**
- * genpd_abort_poweroff - Check if a PM domain power off should be aborted.
- * @genpd: PM domain to check.
- *
- * Return true if a PM domain's status changed to GPD_STATE_ACTIVE during
- * a "power off" operation, which means that a "power on" has occured in the
- * meantime, or if its resume_count field is different from zero, which means
- * that one of its devices has been resumed in the meantime.
- */
-static bool genpd_abort_poweroff(struct generic_pm_domain *genpd)
-{
- return genpd->status == GPD_STATE_WAIT_MASTER
- || genpd->status == GPD_STATE_ACTIVE || genpd->resume_count > 0;
-}
-
-/**
- * genpd_queue_power_off_work - Queue up the execution of pm_genpd_poweroff().
- * @genpd: PM domait to power off.
- *
- * Queue up the execution of pm_genpd_poweroff() unless it's already been done
- * before.
- */
-static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
-{
- queue_work(pm_wq, &genpd->power_off_work);
-}
-
-/**
- * pm_genpd_poweroff - Remove power from a given PM domain.
+ * genpd_poweroff - Remove power from a given PM domain.
* @genpd: PM domain to power down.
+ * @is_async: PM domain is powered down from a scheduled work
*
* If all of the @genpd's devices have been suspended and all of its subdomains
- * have been powered down, run the runtime suspend callbacks provided by all of
- * the @genpd's devices' drivers and remove power from @genpd.
+ * have been powered down, remove power from @genpd.
*/
-static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
- __releases(&genpd->lock) __acquires(&genpd->lock)
+static int genpd_poweroff(struct generic_pm_domain *genpd, bool is_async)
{
struct pm_domain_data *pdd;
struct gpd_link *link;
- unsigned int not_suspended;
- int ret = 0;
+ unsigned int not_suspended = 0;
- start:
/*
* Do not try to power off the domain in the following situations:
* (1) The domain is already in the "power off" state.
- * (2) The domain is waiting for its master to power up.
- * (3) One of the domain's devices is being resumed right now.
- * (4) System suspend is in progress.
+ * (2) System suspend is in progress.
*/
if (genpd->status == GPD_STATE_POWER_OFF
- || genpd->status == GPD_STATE_WAIT_MASTER
- || genpd->resume_count > 0 || genpd->prepared_count > 0)
+ || genpd->prepared_count > 0)
return 0;
if (atomic_read(&genpd->sd_count) > 0)
return -EBUSY;
- not_suspended = 0;
list_for_each_entry(pdd, &genpd->dev_list, list_node) {
enum pm_qos_flags_status stat;
@@ -543,83 +321,35 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
if (stat > PM_QOS_FLAGS_NONE)
return -EBUSY;
- if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
- || pdd->dev->power.irq_safe))
+ if (!pm_runtime_suspended(pdd->dev) || pdd->dev->power.irq_safe)
not_suspended++;
}
- if (not_suspended > genpd->in_progress)
+ if (not_suspended > 1 || (not_suspended == 1 && is_async))
return -EBUSY;
- if (genpd->poweroff_task) {
- /*
- * Another instance of pm_genpd_poweroff() is executing
- * callbacks, so tell it to start over and return.
- */
- genpd->status = GPD_STATE_REPEAT;
- return 0;
- }
-
if (genpd->gov && genpd->gov->power_down_ok) {
if (!genpd->gov->power_down_ok(&genpd->domain))
return -EAGAIN;
}
- genpd->status = GPD_STATE_BUSY;
- genpd->poweroff_task = current;
-
- list_for_each_entry_reverse(pdd, &genpd->dev_list, list_node) {
- ret = atomic_read(&genpd->sd_count) == 0 ?
- __pm_genpd_save_device(pdd, genpd) : -EBUSY;
-
- if (genpd_abort_poweroff(genpd))
- goto out;
-
- if (ret) {
- genpd_set_active(genpd);
- goto out;
- }
-
- if (genpd->status == GPD_STATE_REPEAT) {
- genpd->poweroff_task = NULL;
- goto start;
- }
- }
-
- if (genpd->cpuidle_data) {
- /*
- * If cpuidle_data is set, cpuidle should turn the domain off
- * when the CPU in it is idle. In that case we don't decrement
- * the subdomain counts of the master domains, so that power is
- * not removed from the current domain prematurely as a result
- * of cutting off the masters' power.
- */
- genpd->status = GPD_STATE_POWER_OFF;
- cpuidle_pause_and_lock();
- genpd->cpuidle_data->idle_state->disabled = false;
- cpuidle_resume_and_unlock();
- goto out;
- }
-
if (genpd->power_off) {
- if (atomic_read(&genpd->sd_count) > 0) {
- ret = -EBUSY;
- goto out;
- }
+ int ret;
+
+ if (atomic_read(&genpd->sd_count) > 0)
+ return -EBUSY;
/*
* If sd_count > 0 at this point, one of the subdomains hasn't
- * managed to call pm_genpd_poweron() for the master yet after
- * incrementing it. In that case pm_genpd_poweron() will wait
+ * managed to call genpd_poweron() for the master yet after
+ * incrementing it. In that case genpd_poweron() will wait
* for us to drop the lock, so we can call .power_off() and let
- * the pm_genpd_poweron() restore power for us (this shouldn't
+ * the genpd_poweron() restore power for us (this shouldn't
* happen very often).
*/
- ret = genpd_power_off(genpd);
- if (ret == -EBUSY) {
- genpd_set_active(genpd);
- goto out;
- }
+ ret = genpd_power_off(genpd, true);
+ if (ret)
+ return ret;
}
genpd->status = GPD_STATE_POWER_OFF;
@@ -629,10 +359,7 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
genpd_queue_power_off_work(link->master);
}
- out:
- genpd->poweroff_task = NULL;
- wake_up_all(&genpd->status_wait_queue);
- return ret;
+ return 0;
}
/**
@@ -645,9 +372,9 @@ static void genpd_power_off_work_fn(struct work_struct *work)
genpd = container_of(work, struct generic_pm_domain, power_off_work);
- genpd_acquire_lock(genpd);
- pm_genpd_poweroff(genpd);
- genpd_release_lock(genpd);
+ mutex_lock(&genpd->lock);
+ genpd_poweroff(genpd, true);
+ mutex_unlock(&genpd->lock);
}
/**
@@ -661,8 +388,11 @@ static void genpd_power_off_work_fn(struct work_struct *work)
static int pm_genpd_runtime_suspend(struct device *dev)
{
struct generic_pm_domain *genpd;
- struct generic_pm_domain_data *gpd_data;
bool (*stop_ok)(struct device *__dev);
+ struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
+ bool runtime_pm = pm_runtime_enabled(dev);
+ ktime_t time_start;
+ s64 elapsed_ns;
int ret;
dev_dbg(dev, "%s()\n", __func__);
@@ -671,14 +401,42 @@ static int pm_genpd_runtime_suspend(struct device *dev)
if (IS_ERR(genpd))
return -EINVAL;
+ /*
+ * A runtime PM centric subsystem/driver may re-use the runtime PM
+ * callbacks for other purposes than runtime PM. In those scenarios
+ * runtime PM is disabled. Under these circumstances, we shall skip
+ * validating/measuring the PM QoS latency.
+ */
stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
- if (stop_ok && !stop_ok(dev))
+ if (runtime_pm && stop_ok && !stop_ok(dev))
return -EBUSY;
- ret = genpd_stop_dev(genpd, dev);
+ /* Measure suspend latency. */
+ if (runtime_pm)
+ time_start = ktime_get();
+
+ ret = genpd_save_dev(genpd, dev);
if (ret)
return ret;
+ ret = genpd_stop_dev(genpd, dev);
+ if (ret) {
+ genpd_restore_dev(genpd, dev);
+ return ret;
+ }
+
+ /* Update suspend latency value if the measured time exceeds it. */
+ if (runtime_pm) {
+ elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
+ if (elapsed_ns > td->suspend_latency_ns) {
+ td->suspend_latency_ns = elapsed_ns;
+ dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
+ elapsed_ns);
+ genpd->max_off_time_changed = true;
+ td->constraint_changed = true;
+ }
+ }
+
/*
* If power.irq_safe is set, this routine will be run with interrupts
* off, so it can't use mutexes.
@@ -687,19 +445,7 @@ static int pm_genpd_runtime_suspend(struct device *dev)
return 0;
mutex_lock(&genpd->lock);
-
- /*
- * If we have an unknown state of the need_restore flag, it means none
- * of the runtime PM callbacks has been invoked yet. Let's update the
- * flag to reflect that the current state is active.
- */
- gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
- if (gpd_data->need_restore < 0)
- gpd_data->need_restore = 0;
-
- genpd->in_progress++;
- pm_genpd_poweroff(genpd);
- genpd->in_progress--;
+ genpd_poweroff(genpd, false);
mutex_unlock(&genpd->lock);
return 0;
@@ -716,8 +462,12 @@ static int pm_genpd_runtime_suspend(struct device *dev)
static int pm_genpd_runtime_resume(struct device *dev)
{
struct generic_pm_domain *genpd;
- DEFINE_WAIT(wait);
+ struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
+ bool runtime_pm = pm_runtime_enabled(dev);
+ ktime_t time_start;
+ s64 elapsed_ns;
int ret;
+ bool timed = true;
dev_dbg(dev, "%s()\n", __func__);
@@ -726,39 +476,37 @@ static int pm_genpd_runtime_resume(struct device *dev)
return -EINVAL;
/* If power.irq_safe, the PM domain is never powered off. */
- if (dev->power.irq_safe)
- return genpd_start_dev_no_timing(genpd, dev);
+ if (dev->power.irq_safe) {
+ timed = false;
+ goto out;
+ }
mutex_lock(&genpd->lock);
- ret = __pm_genpd_poweron(genpd);
- if (ret) {
- mutex_unlock(&genpd->lock);
+ ret = __genpd_poweron(genpd);
+ mutex_unlock(&genpd->lock);
+
+ if (ret)
return ret;
- }
- genpd->status = GPD_STATE_BUSY;
- genpd->resume_count++;
- for (;;) {
- prepare_to_wait(&genpd->status_wait_queue, &wait,
- TASK_UNINTERRUPTIBLE);
- /*
- * If current is the powering off task, we have been called
- * reentrantly from one of the device callbacks, so we should
- * not wait.
- */
- if (!genpd->poweroff_task || genpd->poweroff_task == current)
- break;
- mutex_unlock(&genpd->lock);
- schedule();
+ out:
+ /* Measure resume latency. */
+ if (timed && runtime_pm)
+ time_start = ktime_get();
- mutex_lock(&genpd->lock);
+ genpd_start_dev(genpd, dev);
+ genpd_restore_dev(genpd, dev);
+
+ /* Update resume latency value if the measured time exceeds it. */
+ if (timed && runtime_pm) {
+ elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
+ if (elapsed_ns > td->resume_latency_ns) {
+ td->resume_latency_ns = elapsed_ns;
+ dev_dbg(dev, "resume latency exceeded, %lld ns\n",
+ elapsed_ns);
+ genpd->max_off_time_changed = true;
+ td->constraint_changed = true;
+ }
}
- finish_wait(&genpd->status_wait_queue, &wait);
- __pm_genpd_restore_device(dev->power.subsys_data->domain_data, genpd);
- genpd->resume_count--;
- genpd_set_active(genpd);
- wake_up_all(&genpd->status_wait_queue);
- mutex_unlock(&genpd->lock);
return 0;
}
@@ -772,15 +520,15 @@ static int __init pd_ignore_unused_setup(char *__unused)
__setup("pd_ignore_unused", pd_ignore_unused_setup);
/**
- * pm_genpd_poweroff_unused - Power off all PM domains with no devices in use.
+ * genpd_poweroff_unused - Power off all PM domains with no devices in use.
*/
-void pm_genpd_poweroff_unused(void)
+static int __init genpd_poweroff_unused(void)
{
struct generic_pm_domain *genpd;
if (pd_ignore_unused) {
pr_warn("genpd: Not disabling unused power domains\n");
- return;
+ return 0;
}
mutex_lock(&gpd_list_lock);
@@ -789,11 +537,7 @@ void pm_genpd_poweroff_unused(void)
genpd_queue_power_off_work(genpd);
mutex_unlock(&gpd_list_lock);
-}
-static int __init genpd_poweroff_unused(void)
-{
- pm_genpd_poweroff_unused();
return 0;
}
late_initcall(genpd_poweroff_unused);
@@ -827,6 +571,7 @@ static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
/**
* pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
* @genpd: PM domain to power off, if possible.
+ * @timed: True if latency measurements are allowed.
*
* Check if the given PM domain can be powered off (during system suspend or
* hibernation) and do that if so. Also, in that case propagate to its masters.
@@ -836,7 +581,8 @@ static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
* executed sequentially, so it is guaranteed that it will never run twice in
* parallel).
*/
-static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd)
+static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd,
+ bool timed)
{
struct gpd_link *link;
@@ -847,38 +593,40 @@ static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd)
|| atomic_read(&genpd->sd_count) > 0)
return;
- genpd_power_off(genpd);
+ genpd_power_off(genpd, timed);
genpd->status = GPD_STATE_POWER_OFF;
list_for_each_entry(link, &genpd->slave_links, slave_node) {
genpd_sd_counter_dec(link->master);
- pm_genpd_sync_poweroff(link->master);
+ pm_genpd_sync_poweroff(link->master, timed);
}
}
/**
* pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
* @genpd: PM domain to power on.
+ * @timed: True if latency measurements are allowed.
*
* This function is only called in "noirq" and "syscore" stages of system power
* transitions, so it need not acquire locks (all of the "noirq" callbacks are
* executed sequentially, so it is guaranteed that it will never run twice in
* parallel).
*/
-static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd)
+static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd,
+ bool timed)
{
struct gpd_link *link;
- if (genpd->status != GPD_STATE_POWER_OFF)
+ if (genpd->status == GPD_STATE_ACTIVE)
return;
list_for_each_entry(link, &genpd->slave_links, slave_node) {
- pm_genpd_sync_poweron(link->master);
+ pm_genpd_sync_poweron(link->master, timed);
genpd_sd_counter_inc(link->master);
}
- genpd_power_on(genpd);
+ genpd_power_on(genpd, timed);
genpd->status = GPD_STATE_ACTIVE;
}
@@ -947,14 +695,14 @@ static int pm_genpd_prepare(struct device *dev)
if (resume_needed(dev, genpd))
pm_runtime_resume(dev);
- genpd_acquire_lock(genpd);
+ mutex_lock(&genpd->lock);
if (genpd->prepared_count++ == 0) {
genpd->suspended_count = 0;
genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
}
- genpd_release_lock(genpd);
+ mutex_unlock(&genpd->lock);
if (genpd->suspend_power_off) {
pm_runtime_put_noidle(dev);
@@ -963,7 +711,7 @@ static int pm_genpd_prepare(struct device *dev)
/*
* The PM domain must be in the GPD_STATE_ACTIVE state at this point,
- * so pm_genpd_poweron() will return immediately, but if the device
+ * so genpd_poweron() will return immediately, but if the device
* is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
* to make it operational.
*/
@@ -1056,7 +804,7 @@ static int pm_genpd_suspend_noirq(struct device *dev)
* the same PM domain, so it is not necessary to use locking here.
*/
genpd->suspended_count++;
- pm_genpd_sync_poweroff(genpd);
+ pm_genpd_sync_poweroff(genpd, true);
return 0;
}
@@ -1086,7 +834,7 @@ static int pm_genpd_resume_noirq(struct device *dev)
* guaranteed that this function will never run twice in parallel for
* the same PM domain, so it is not necessary to use locking here.
*/
- pm_genpd_sync_poweron(genpd);
+ pm_genpd_sync_poweron(genpd, true);
genpd->suspended_count--;
return genpd_start_dev(genpd, dev);
@@ -1217,7 +965,8 @@ static int pm_genpd_thaw_noirq(struct device *dev)
if (IS_ERR(genpd))
return -EINVAL;
- return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev);
+ return genpd->suspend_power_off ?
+ 0 : genpd_start_dev(genpd, dev);
}
/**
@@ -1300,7 +1049,7 @@ static int pm_genpd_restore_noirq(struct device *dev)
* If the domain was off before the hibernation, make
* sure it will be off going forward.
*/
- genpd_power_off(genpd);
+ genpd_power_off(genpd, true);
return 0;
}
@@ -1309,7 +1058,7 @@ static int pm_genpd_restore_noirq(struct device *dev)
if (genpd->suspend_power_off)
return 0;
- pm_genpd_sync_poweron(genpd);
+ pm_genpd_sync_poweron(genpd, true);
return genpd_start_dev(genpd, dev);
}
@@ -1367,9 +1116,9 @@ static void genpd_syscore_switch(struct device *dev, bool suspend)
if (suspend) {
genpd->suspended_count++;
- pm_genpd_sync_poweroff(genpd);
+ pm_genpd_sync_poweroff(genpd, false);
} else {
- pm_genpd_sync_poweron(genpd);
+ pm_genpd_sync_poweron(genpd, false);
genpd->suspended_count--;
}
}
@@ -1427,7 +1176,6 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
gpd_data->td = *td;
gpd_data->base.dev = dev;
- gpd_data->need_restore = -1;
gpd_data->td.constraint_changed = true;
gpd_data->td.effective_constraint_ns = -1;
gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
@@ -1489,7 +1237,7 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
if (IS_ERR(gpd_data))
return PTR_ERR(gpd_data);
- genpd_acquire_lock(genpd);
+ mutex_lock(&genpd->lock);
if (genpd->prepared_count > 0) {
ret = -EAGAIN;
@@ -1506,7 +1254,7 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
out:
- genpd_release_lock(genpd);
+ mutex_unlock(&genpd->lock);
if (ret)
genpd_free_dev_data(dev, gpd_data);
@@ -1517,18 +1265,6 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
}
/**
- * __pm_genpd_name_add_device - Find I/O PM domain and add a device to it.
- * @domain_name: Name of the PM domain to add the device to.
- * @dev: Device to be added.
- * @td: Set of PM QoS timing parameters to attach to the device.
- */
-int __pm_genpd_name_add_device(const char *domain_name, struct device *dev,
- struct gpd_timing_data *td)
-{
- return __pm_genpd_add_device(pm_genpd_lookup_name(domain_name), dev, td);
-}
-
-/**
* pm_genpd_remove_device - Remove a device from an I/O PM domain.
* @genpd: PM domain to remove the device from.
* @dev: Device to be removed.
@@ -1550,7 +1286,7 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
gpd_data = to_gpd_data(pdd);
dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
- genpd_acquire_lock(genpd);
+ mutex_lock(&genpd->lock);
if (genpd->prepared_count > 0) {
ret = -EAGAIN;
@@ -1565,14 +1301,14 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
list_del_init(&pdd->list_node);
- genpd_release_lock(genpd);
+ mutex_unlock(&genpd->lock);
genpd_free_dev_data(dev, gpd_data);
return 0;
out:
- genpd_release_lock(genpd);
+ mutex_unlock(&genpd->lock);
dev_pm_qos_add_notifier(dev, &gpd_data->nb);
return ret;
@@ -1586,23 +1322,19 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *subdomain)
{
- struct gpd_link *link;
+ struct gpd_link *link, *itr;
int ret = 0;
if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
|| genpd == subdomain)
return -EINVAL;
- start:
- genpd_acquire_lock(genpd);
- mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
+ link = kzalloc(sizeof(*link), GFP_KERNEL);
+ if (!link)
+ return -ENOMEM;
- if (subdomain->status != GPD_STATE_POWER_OFF
- && subdomain->status != GPD_STATE_ACTIVE) {
- mutex_unlock(&subdomain->lock);
- genpd_release_lock(genpd);
- goto start;
- }
+ mutex_lock(&genpd->lock);
+ mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
if (genpd->status == GPD_STATE_POWER_OFF
&& subdomain->status != GPD_STATE_POWER_OFF) {
@@ -1610,18 +1342,13 @@ int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
goto out;
}
- list_for_each_entry(link, &genpd->master_links, master_node) {
- if (link->slave == subdomain && link->master == genpd) {
+ list_for_each_entry(itr, &genpd->master_links, master_node) {
+ if (itr->slave == subdomain && itr->master == genpd) {
ret = -EINVAL;
goto out;
}
}
- link = kzalloc(sizeof(*link), GFP_KERNEL);
- if (!link) {
- ret = -ENOMEM;
- goto out;
- }
link->master = genpd;
list_add_tail(&link->master_node, &genpd->master_links);
link->slave = subdomain;
@@ -1631,39 +1358,12 @@ int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
out:
mutex_unlock(&subdomain->lock);
- genpd_release_lock(genpd);
-
+ mutex_unlock(&genpd->lock);
+ if (ret)
+ kfree(link);
return ret;
}
-
-/**
- * pm_genpd_add_subdomain_names - Add a subdomain to an I/O PM domain.
- * @master_name: Name of the master PM domain to add the subdomain to.
- * @subdomain_name: Name of the subdomain to be added.
- */
-int pm_genpd_add_subdomain_names(const char *master_name,
- const char *subdomain_name)
-{
- struct generic_pm_domain *master = NULL, *subdomain = NULL, *gpd;
-
- if (IS_ERR_OR_NULL(master_name) || IS_ERR_OR_NULL(subdomain_name))
- return -EINVAL;
-
- mutex_lock(&gpd_list_lock);
- list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
- if (!master && !strcmp(gpd->name, master_name))
- master = gpd;
-
- if (!subdomain && !strcmp(gpd->name, subdomain_name))
- subdomain = gpd;
-
- if (master && subdomain)
- break;
- }
- mutex_unlock(&gpd_list_lock);
-
- return pm_genpd_add_subdomain(master, subdomain);
-}
+EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
/**
* pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
@@ -1679,8 +1379,14 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
return -EINVAL;
- start:
- genpd_acquire_lock(genpd);
+ mutex_lock(&genpd->lock);
+
+ if (!list_empty(&subdomain->slave_links) || subdomain->device_count) {
+ pr_warn("%s: unable to remove subdomain %s\n", genpd->name,
+ subdomain->name);
+ ret = -EBUSY;
+ goto out;
+ }
list_for_each_entry(link, &genpd->master_links, master_node) {
if (link->slave != subdomain)
@@ -1688,13 +1394,6 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
- if (subdomain->status != GPD_STATE_POWER_OFF
- && subdomain->status != GPD_STATE_ACTIVE) {
- mutex_unlock(&subdomain->lock);
- genpd_release_lock(genpd);
- goto start;
- }
-
list_del(&link->master_node);
list_del(&link->slave_node);
kfree(link);
@@ -1707,128 +1406,12 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
break;
}
- genpd_release_lock(genpd);
-
- return ret;
-}
-
-/**
- * pm_genpd_attach_cpuidle - Connect the given PM domain with cpuidle.
- * @genpd: PM domain to be connected with cpuidle.
- * @state: cpuidle state this domain can disable/enable.
- *
- * Make a PM domain behave as though it contained a CPU core, that is, instead
- * of calling its power down routine it will enable the given cpuidle state so
- * that the cpuidle subsystem can power it down (if possible and desirable).
- */
-int pm_genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state)
-{
- struct cpuidle_driver *cpuidle_drv;
- struct gpd_cpuidle_data *cpuidle_data;
- struct cpuidle_state *idle_state;
- int ret = 0;
-
- if (IS_ERR_OR_NULL(genpd) || state < 0)
- return -EINVAL;
-
- genpd_acquire_lock(genpd);
-
- if (genpd->cpuidle_data) {
- ret = -EEXIST;
- goto out;
- }
- cpuidle_data = kzalloc(sizeof(*cpuidle_data), GFP_KERNEL);
- if (!cpuidle_data) {
- ret = -ENOMEM;
- goto out;
- }
- cpuidle_drv = cpuidle_driver_ref();
- if (!cpuidle_drv) {
- ret = -ENODEV;
- goto err_drv;
- }
- if (cpuidle_drv->state_count <= state) {
- ret = -EINVAL;
- goto err;
- }
- idle_state = &cpuidle_drv->states[state];
- if (!idle_state->disabled) {
- ret = -EAGAIN;
- goto err;
- }
- cpuidle_data->idle_state = idle_state;
- cpuidle_data->saved_exit_latency = idle_state->exit_latency;
- genpd->cpuidle_data = cpuidle_data;
- genpd_recalc_cpu_exit_latency(genpd);
-
- out:
- genpd_release_lock(genpd);
- return ret;
-
- err:
- cpuidle_driver_unref();
-
- err_drv:
- kfree(cpuidle_data);
- goto out;
-}
-
-/**
- * pm_genpd_name_attach_cpuidle - Find PM domain and connect cpuidle to it.
- * @name: Name of the domain to connect to cpuidle.
- * @state: cpuidle state this domain can manipulate.
- */
-int pm_genpd_name_attach_cpuidle(const char *name, int state)
-{
- return pm_genpd_attach_cpuidle(pm_genpd_lookup_name(name), state);
-}
-
-/**
- * pm_genpd_detach_cpuidle - Remove the cpuidle connection from a PM domain.
- * @genpd: PM domain to remove the cpuidle connection from.
- *
- * Remove the cpuidle connection set up by pm_genpd_attach_cpuidle() from the
- * given PM domain.
- */
-int pm_genpd_detach_cpuidle(struct generic_pm_domain *genpd)
-{
- struct gpd_cpuidle_data *cpuidle_data;
- struct cpuidle_state *idle_state;
- int ret = 0;
-
- if (IS_ERR_OR_NULL(genpd))
- return -EINVAL;
-
- genpd_acquire_lock(genpd);
-
- cpuidle_data = genpd->cpuidle_data;
- if (!cpuidle_data) {
- ret = -ENODEV;
- goto out;
- }
- idle_state = cpuidle_data->idle_state;
- if (!idle_state->disabled) {
- ret = -EAGAIN;
- goto out;
- }
- idle_state->exit_latency = cpuidle_data->saved_exit_latency;
- cpuidle_driver_unref();
- genpd->cpuidle_data = NULL;
- kfree(cpuidle_data);
+out:
+ mutex_unlock(&genpd->lock);
- out:
- genpd_release_lock(genpd);
return ret;
}
-
-/**
- * pm_genpd_name_detach_cpuidle - Find PM domain and disconnect cpuidle from it.
- * @name: Name of the domain to disconnect cpuidle from.
- */
-int pm_genpd_name_detach_cpuidle(const char *name)
-{
- return pm_genpd_detach_cpuidle(pm_genpd_lookup_name(name));
-}
+EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
/* Default device callbacks for generic PM domains. */
@@ -1896,12 +1479,8 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
mutex_init(&genpd->lock);
genpd->gov = gov;
INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
- genpd->in_progress = 0;
atomic_set(&genpd->sd_count, 0);
genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
- init_waitqueue_head(&genpd->status_wait_queue);
- genpd->poweroff_task = NULL;
- genpd->resume_count = 0;
genpd->device_count = 0;
genpd->max_off_time_ns = -1;
genpd->max_off_time_changed = true;
@@ -1939,6 +1518,7 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
list_add(&genpd->gpd_list_node, &gpd_list);
mutex_unlock(&gpd_list_lock);
}
+EXPORT_SYMBOL_GPL(pm_genpd_init);
#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
/*
@@ -2112,7 +1692,7 @@ EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
/**
* genpd_dev_pm_detach - Detach a device from its PM domain.
- * @dev: Device to attach.
+ * @dev: Device to detach.
* @power_off: Currently not used
*
* Try to locate a corresponding generic PM domain, which the device was
@@ -2121,6 +1701,7 @@ EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
static void genpd_dev_pm_detach(struct device *dev, bool power_off)
{
struct generic_pm_domain *pd;
+ unsigned int i;
int ret = 0;
pd = pm_genpd_lookup_dev(dev);
@@ -2129,10 +1710,12 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off)
dev_dbg(dev, "removing from PM domain %s\n", pd->name);
- while (1) {
+ for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
ret = pm_genpd_remove_device(pd, dev);
if (ret != -EAGAIN)
break;
+
+ mdelay(i);
cond_resched();
}
@@ -2167,12 +1750,16 @@ static void genpd_dev_pm_sync(struct device *dev)
* Both generic and legacy Samsung-specific DT bindings are supported to keep
* backwards compatibility with existing DTBs.
*
- * Returns 0 on successfully attached PM domain or negative error code.
+ * Returns 0 on successfully attached PM domain or negative error code. Note
+ * that if a power-domain exists for the device, but it cannot be found or
+ * turned on, then return -EPROBE_DEFER to ensure that the device is not
+ * probed and to re-try again later.
*/
int genpd_dev_pm_attach(struct device *dev)
{
struct of_phandle_args pd_args;
struct generic_pm_domain *pd;
+ unsigned int i;
int ret;
if (!dev->of_node)
@@ -2199,34 +1786,36 @@ int genpd_dev_pm_attach(struct device *dev)
}
pd = of_genpd_get_from_provider(&pd_args);
+ of_node_put(pd_args.np);
if (IS_ERR(pd)) {
dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
__func__, PTR_ERR(pd));
- of_node_put(dev->of_node);
- return PTR_ERR(pd);
+ return -EPROBE_DEFER;
}
dev_dbg(dev, "adding to PM domain %s\n", pd->name);
- while (1) {
+ for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
ret = pm_genpd_add_device(pd, dev);
if (ret != -EAGAIN)
break;
+
+ mdelay(i);
cond_resched();
}
if (ret < 0) {
dev_err(dev, "failed to add to PM domain %s: %d",
pd->name, ret);
- of_node_put(dev->of_node);
- return ret;
+ goto out;
}
dev->pm_domain->detach = genpd_dev_pm_detach;
dev->pm_domain->sync = genpd_dev_pm_sync;
- pm_genpd_poweron(pd);
+ ret = genpd_poweron(pd);
- return 0;
+out:
+ return ret ? -EPROBE_DEFER : 0;
}
EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
@@ -2274,9 +1863,6 @@ static int pm_genpd_summary_one(struct seq_file *s,
{
static const char * const status_lookup[] = {
[GPD_STATE_ACTIVE] = "on",
- [GPD_STATE_WAIT_MASTER] = "wait-master",
- [GPD_STATE_BUSY] = "busy",
- [GPD_STATE_REPEAT] = "off-in-progress",
[GPD_STATE_POWER_OFF] = "off"
};
struct pm_domain_data *pm_data;
@@ -2290,7 +1876,7 @@ static int pm_genpd_summary_one(struct seq_file *s,
if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
goto exit;
- seq_printf(s, "%-30s %-15s ", genpd->name, status_lookup[genpd->status]);
+ seq_printf(s, "%-30s %-15s ", genpd->name, status_lookup[genpd->status]);
/*
* Modifications on the list require holding locks on both
@@ -2325,8 +1911,8 @@ static int pm_genpd_summary_show(struct seq_file *s, void *data)
struct generic_pm_domain *genpd;
int ret = 0;
- seq_puts(s, " domain status slaves\n");
- seq_puts(s, " /device runtime status\n");
+ seq_puts(s, "domain status slaves\n");
+ seq_puts(s, " /device runtime status\n");
seq_puts(s, "----------------------------------------------------------------------\n");
ret = mutex_lock_interruptible(&gpd_list_lock);