PM / sleep: Use valid_state() for platform-dependent sleep states only

commit 43e8317b0bba1d6eb85f38a4a233d82d7c20d732 upstream.

Use the observation that, for platform-dependent sleep states
(PM_SUSPEND_STANDBY, PM_SUSPEND_MEM), a given state is either
always supported or always unsupported and store that information
in pm_states[] instead of calling valid_state() every time we
need to check it.

Also do not use valid_state() for PM_SUSPEND_FREEZE, which is always
valid, and move the pm_test_level validity check for PM_SUSPEND_FREEZE
directly into enter_state().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/kernel/power/main.c b/kernel/power/main.c
index ddad61f..3ae41cd 100644 (file)
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -296,7 +296,7 @@ static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
        suspend_state_t i;
 
        for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
-               if (valid_state(i))
+               if (pm_states[i].state)
                        s += sprintf(s,"%s ", pm_states[i].label);
 
 #endif
@@ -328,8 +328,9 @@ static suspend_state_t decode_state(const char *buf, size_t n)
 
 #ifdef CONFIG_SUSPEND
        for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++)
-               if (len == strlen(s->label) && !strncmp(buf, s->label, len))
-                       return state;
+               if (s->state && len == strlen(s->label)
+                   && !strncmp(buf, s->label, len))
+                       return s->state;
 #endif
 
        return PM_SUSPEND_ON;
@@ -447,7 +448,7 @@ static ssize_t autosleep_show(struct kobject *kobj,
 
 #ifdef CONFIG_SUSPEND
        if (state < PM_SUSPEND_MAX)
-               return sprintf(buf, "%s\n", valid_state(state) ?
+               return sprintf(buf, "%s\n", pm_states[state].state ?
                                        pm_states[state].label : "error");
 #endif
 #ifdef CONFIG_HIBERNATION

diff --git a/kernel/power/power.h b/kernel/power/power.h
index 10d9075..f770cad 100644 (file)
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -183,14 +183,12 @@ struct pm_sleep_state {
 /* kernel/power/suspend.c */
 extern struct pm_sleep_state pm_states[];
 
-extern bool valid_state(suspend_state_t state);
 extern int suspend_devices_and_enter(suspend_state_t state);
 #else /* !CONFIG_SUSPEND */
 static inline int suspend_devices_and_enter(suspend_state_t state)
 {
        return -ENOSYS;
 }
-static inline bool valid_state(suspend_state_t state) { return false; }
 #endif /* !CONFIG_SUSPEND */
 
 #ifdef CONFIG_PM_TEST_SUSPEND

diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 222ea9d..5455d5c 100644 (file)
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -30,9 +30,9 @@
 #include "power.h"
 
 struct pm_sleep_state pm_states[PM_SUSPEND_MAX] = {
-       [PM_SUSPEND_FREEZE] = { "freeze", PM_SUSPEND_FREEZE },
-       [PM_SUSPEND_STANDBY] = { "standby", PM_SUSPEND_STANDBY },
-       [PM_SUSPEND_MEM] = { "mem", PM_SUSPEND_MEM },
+       [PM_SUSPEND_FREEZE] = { .label = "freeze", .state = PM_SUSPEND_FREEZE },
+       [PM_SUSPEND_STANDBY] = { .label = "standby", },
+       [PM_SUSPEND_MEM] = { .label = "mem", },
 };
 
 static const struct platform_suspend_ops *suspend_ops;
@@ -62,42 +62,34 @@ void freeze_wake(void)
 }
 EXPORT_SYMBOL_GPL(freeze_wake);
 
+static bool valid_state(suspend_state_t state)
+{
+       /*
+        * PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
+        * support and need to be valid to the low level
+        * implementation, no valid callback implies that none are valid.
+        */
+       return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
+}
+
 /**
  * suspend_set_ops - Set the global suspend method table.
  * @ops: Suspend operations to use.
  */
 void suspend_set_ops(const struct platform_suspend_ops *ops)
 {
+       suspend_state_t i;
+
        lock_system_sleep();
+
        suspend_ops = ops;
+       for (i = PM_SUSPEND_STANDBY; i <= PM_SUSPEND_MEM; i++)
+               pm_states[i].state = valid_state(i) ? i : 0;
+
        unlock_system_sleep();
 }
 EXPORT_SYMBOL_GPL(suspend_set_ops);
 
-bool valid_state(suspend_state_t state)
-{
-       if (state == PM_SUSPEND_FREEZE) {
-#ifdef CONFIG_PM_DEBUG
-               if (pm_test_level != TEST_NONE &&
-                   pm_test_level != TEST_FREEZER &&
-                   pm_test_level != TEST_DEVICES &&
-                   pm_test_level != TEST_PLATFORM) {
-                       printk(KERN_WARNING "Unsupported pm_test mode for "
-                                       "freeze state, please choose "
-                                       "none/freezer/devices/platform.\n");
-                       return false;
-               }
-#endif
-                       return true;
-       }
-       /*
-        * PM_SUSPEND_STANDBY and PM_SUSPEND_MEMORY states need lowlevel
-        * support and need to be valid to the lowlevel
-        * implementation, no valid callback implies that none are valid.
-        */
-       return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
-}
-
 /**
  * suspend_valid_only_mem - Generic memory-only valid callback.
  *
@@ -324,9 +316,17 @@ static int enter_state(suspend_state_t state)
 {
        int error;
 
-       if (!valid_state(state))
-               return -ENODEV;
-
+       if (state == PM_SUSPEND_FREEZE) {
+#ifdef CONFIG_PM_DEBUG
+               if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
+                       pr_warning("PM: Unsupported test mode for freeze state,"
+                                  "please choose none/freezer/devices/platform.\n");
+                       return -EAGAIN;
+               }
+#endif
+       } else if (!valid_state(state)) {
+               return -EINVAL;
+       }
        if (!mutex_trylock(&pm_mutex))
                return -EBUSY;
 

diff --git a/kernel/power/suspend_test.c b/kernel/power/suspend_test.c
index d4e3ab1..269b097 100644 (file)
--- a/kernel/power/suspend_test.c
+++ b/kernel/power/suspend_test.c
@@ -162,7 +162,7 @@ static int __init test_suspend(void)
        /* PM is initialized by now; is that state testable? */
        if (test_state == PM_SUSPEND_ON)
                goto done;
-       if (!valid_state(test_state)) {
+       if (!pm_states[test_state].state) {
                printk(warn_bad_state, pm_states[test_state].label);
                goto done;
        }