From: Rafael J. Wysocki <rjw@xxxxxxx> Instead of keeping all devices in the same list during system suspend and resume, regardless of what suspend-resume callbacks have been executed for them already, use separate lists of devices that have had their ->prepare(), ->suspend() and ->suspend_noirq() callbacks executed. This will allow us to simplify the core device suspend and resume routines. Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> --- drivers/base/power/main.c | 53 ++++++++++++++++------------------------------ 1 file changed, 19 insertions(+), 34 deletions(-) Index: linux-2.6/drivers/base/power/main.c =================================================================== --- linux-2.6.orig/drivers/base/power/main.c +++ linux-2.6/drivers/base/power/main.c @@ -42,6 +42,9 @@ */ LIST_HEAD(dpm_list); +LIST_HEAD(dpm_prepared_list); +LIST_HEAD(dpm_suspended_list); +LIST_HEAD(dpm_noirq_list); static DEFINE_MUTEX(dpm_list_mtx); static pm_message_t pm_transition; @@ -476,14 +479,12 @@ End: */ void dpm_resume_noirq(pm_message_t state) { - struct list_head list; ktime_t starttime = ktime_get(); - INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); transition_started = false; - while (!list_empty(&dpm_list)) { - struct device *dev = to_device(dpm_list.next); + while (!list_empty(&dpm_noirq_list)) { + struct device *dev = to_device(dpm_noirq_list.next); get_device(dev); if (dev->power.status > DPM_OFF) { @@ -499,10 +500,9 @@ void dpm_resume_noirq(pm_message_t state pm_dev_err(dev, state, " early", error); } if (!list_empty(&dev->power.entry)) - list_move_tail(&dev->power.entry, &list); + list_move_tail(&dev->power.entry, &dpm_suspended_list); put_device(dev); } - list_splice(&list, &dpm_list); mutex_unlock(&dpm_list_mtx); dpm_show_time(starttime, state, "early"); resume_device_irqs(); @@ -611,16 +611,14 @@ static bool is_async(struct device *dev) */ static void dpm_resume(pm_message_t state) { - struct list_head list; struct device *dev; ktime_t starttime = ktime_get(); - INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); pm_transition = state; async_error = 0; - list_for_each_entry(dev, &dpm_list, power.entry) { + list_for_each_entry(dev, &dpm_suspended_list, power.entry) { if (dev->power.status < DPM_OFF) continue; @@ -631,8 +629,8 @@ static void dpm_resume(pm_message_t stat } } - while (!list_empty(&dpm_list)) { - dev = to_device(dpm_list.next); + while (!list_empty(&dpm_suspended_list)) { + dev = to_device(dpm_suspended_list.next); get_device(dev); if (dev->power.status >= DPM_OFF && !is_async(dev)) { int error; @@ -644,15 +642,11 @@ static void dpm_resume(pm_message_t stat mutex_lock(&dpm_list_mtx); if (error) pm_dev_err(dev, state, "", error); - } else if (dev->power.status == DPM_SUSPENDING) { - /* Allow new children of the device to be registered */ - dev->power.status = DPM_RESUMING; } if (!list_empty(&dev->power.entry)) - list_move_tail(&dev->power.entry, &list); + list_move_tail(&dev->power.entry, &dpm_prepared_list); put_device(dev); } - list_splice(&list, &dpm_list); mutex_unlock(&dpm_list_mtx); async_synchronize_full(); dpm_show_time(starttime, state, NULL); @@ -699,8 +693,8 @@ static void dpm_complete(pm_message_t st INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); transition_started = false; - while (!list_empty(&dpm_list)) { - struct device *dev = to_device(dpm_list.prev); + while (!list_empty(&dpm_prepared_list)) { + struct device *dev = to_device(dpm_prepared_list.prev); get_device(dev); if (dev->power.status > DPM_ON) { @@ -803,15 +797,13 @@ End: */ int dpm_suspend_noirq(pm_message_t state) { - struct list_head list; ktime_t starttime = ktime_get(); int error = 0; - INIT_LIST_HEAD(&list); suspend_device_irqs(); mutex_lock(&dpm_list_mtx); - while (!list_empty(&dpm_list)) { - struct device *dev = to_device(dpm_list.prev); + while (!list_empty(&dpm_suspended_list)) { + struct device *dev = to_device(dpm_suspended_list.prev); get_device(dev); mutex_unlock(&dpm_list_mtx); @@ -826,10 +818,9 @@ int dpm_suspend_noirq(pm_message_t state } dev->power.status = DPM_OFF_IRQ; if (!list_empty(&dev->power.entry)) - list_move(&dev->power.entry, &list); + list_move(&dev->power.entry, &dpm_noirq_list); put_device(dev); } - list_splice_tail(&list, &dpm_list); mutex_unlock(&dpm_list_mtx); if (error) dpm_resume_noirq(resume_event(state)); @@ -957,16 +948,14 @@ static int device_suspend(struct device */ static int dpm_suspend(pm_message_t state) { - struct list_head list; ktime_t starttime = ktime_get(); int error = 0; - INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); pm_transition = state; async_error = 0; - while (!list_empty(&dpm_list)) { - struct device *dev = to_device(dpm_list.prev); + while (!list_empty(&dpm_prepared_list)) { + struct device *dev = to_device(dpm_prepared_list.prev); get_device(dev); mutex_unlock(&dpm_list_mtx); @@ -980,12 +969,11 @@ static int dpm_suspend(pm_message_t stat break; } if (!list_empty(&dev->power.entry)) - list_move(&dev->power.entry, &list); + list_move(&dev->power.entry, &dpm_suspended_list); put_device(dev); if (async_error) break; } - list_splice(&list, dpm_list.prev); mutex_unlock(&dpm_list_mtx); async_synchronize_full(); if (!error) @@ -1044,10 +1032,8 @@ static int device_prepare(struct device */ static int dpm_prepare(pm_message_t state) { - struct list_head list; int error = 0; - INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); transition_started = true; while (!list_empty(&dpm_list)) { @@ -1084,10 +1070,9 @@ static int dpm_prepare(pm_message_t stat } dev->power.status = DPM_SUSPENDING; if (!list_empty(&dev->power.entry)) - list_move_tail(&dev->power.entry, &list); + list_move_tail(&dev->power.entry, &dpm_prepared_list); put_device(dev); } - list_splice(&list, &dpm_list); mutex_unlock(&dpm_list_mtx); return error; } _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm