In analogy with commits 5af84b82701a and 97df8c12995,
using asynchronous threads can improve the overall
suspend time significantly.
This patch is for dpm_prepare phase.
Signed-off-by: Chuansheng Liu <chuansheng....@intel.com>
Signed-off-by: xiaoming wang <xiaoming.w...@intel.com>
---
drivers/base/power/main.c | 57 +++++++++++++++++++++++++++++++++++++++++----
1 files changed, 52 insertions(+), 5 deletions(-)
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index b67d9ae..f9fe1b3 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -1531,15 +1531,24 @@ int dpm_suspend(pm_message_t state)
* Execute the ->prepare() callback(s) for given device. No new children of
the
* device may be registered after this function has returned.
*/
-static int device_prepare(struct device *dev, pm_message_t state)
+static int __device_prepare(struct device *dev, pm_message_t state, bool async)
{
int (*callback)(struct device *) = NULL;
char *info = NULL;
int ret = 0;
+ if (async_error)
+ goto Complete;
+
+ if (pm_wakeup_pending()) {
+ async_error = -EBUSY;
+ goto Complete;
+ }
+
if (dev->power.syscore)
- return 0;
+ goto Complete;
+ dpm_wait_for_children(dev, async);
/*
* If a device's parent goes into runtime suspend at the wrong time,
* it won't be possible to resume the device. To prevent this we
@@ -1582,7 +1591,7 @@ static int device_prepare(struct device *dev,
pm_message_t state)
if (ret < 0) {
suspend_report_result(callback, ret);
pm_runtime_put(dev);
- return ret;
+ goto Complete;
}
/*
* A positive return value from ->prepare() means "this device appears
@@ -1594,9 +1603,40 @@ static int device_prepare(struct device *dev,
pm_message_t state)
spin_lock_irq(&dev->power.lock);
dev->power.direct_complete = ret > 0 && state.event == PM_EVENT_SUSPEND;
spin_unlock_irq(&dev->power.lock);
- return 0;
+
+Complete:
+ complete_all(&dev->power.completion);
+ if (ret)
+ async_error = ret;
+
+ return ret;
+}
+
+static void async_prepare(void *data, async_cookie_t cookie)
+{
+ struct device *dev = (struct device *)data;
+ int error;
+
+ error = __device_prepare(dev, pm_transition, true);
+ if (error) {
+ dpm_save_failed_dev(dev_name(dev));
+ pm_dev_err(dev, pm_transition, " async", error);
+ }
+ put_device(dev);
+}
+
+static int device_prepare(struct device *dev)
+{
+ reinit_completion(&dev->power.completion);
+ if (pm_async_enabled && dev->power.async_suspend) {
+ get_device(dev);
+ async_schedule(async_prepare, dev);
+ return 0;
+ }
+ return __device_prepare(dev, pm_transition, false);
}
+
/**
* dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
* @state: PM transition of the system being carried out.
@@ -1611,13 +1651,15 @@ int dpm_prepare(pm_message_t state)
might_sleep();
mutex_lock(&dpm_list_mtx);
+ pm_transition = state;
+ async_error = 0;
while (!list_empty(&dpm_list)) {
struct device *dev = to_device(dpm_list.next);
get_device(dev);
mutex_unlock(&dpm_list_mtx);
- error = device_prepare(dev, state);
+ error = device_prepare(dev);
mutex_lock(&dpm_list_mtx);
if (error) {
@@ -1636,8 +1678,13 @@ int dpm_prepare(pm_message_t state)
if (!list_empty(&dev->power.entry))
list_move_tail(&dev->power.entry, &dpm_prepared_list);
put_device(dev);
+ if (async_error)
+ break;
}
mutex_unlock(&dpm_list_mtx);
+ async_synchronize_full();
+ if (!error)
+ error = async_error;
trace_suspend_resume(TPS("dpm_prepare"), state.event, false);
return error;
}
--
1.7.1
--
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