tracing: Adjust conditional expression latency formatting.
[linux-2.6.git] / kernel / power / main.c
index d0cedaa..7018530 100644 (file)
@@ -8,19 +8,10 @@
  *
  */
 
-#include <linux/module.h>
-#include <linux/suspend.h>
 #include <linux/kobject.h>
 #include <linux/string.h>
-#include <linux/delay.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-#include <linux/console.h>
-#include <linux/cpu.h>
 #include <linux/resume-trace.h>
-#include <linux/freezer.h>
-#include <linux/vmstat.h>
-#include <linux/syscalls.h>
+#include <linux/workqueue.h>
 
 #include "power.h"
 
@@ -53,23 +44,35 @@ int pm_notifier_call_chain(unsigned long val)
                        == NOTIFY_BAD) ? -EINVAL : 0;
 }
 
-#endif /* CONFIG_PM_SLEEP */
-
-#ifdef CONFIG_SUSPEND
+/* If set, devices may be suspended and resumed asynchronously. */
+int pm_async_enabled = 1;
 
-#ifdef CONFIG_PM_DEBUG
-int pm_test_level = TEST_NONE;
+static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
+                            char *buf)
+{
+       return sprintf(buf, "%d\n", pm_async_enabled);
+}
 
-static int suspend_test(int level)
+static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
+                             const char *buf, size_t n)
 {
-       if (pm_test_level == level) {
-               printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n");
-               mdelay(5000);
-               return 1;
-       }
-       return 0;
+       unsigned long val;
+
+       if (strict_strtoul(buf, 10, &val))
+               return -EINVAL;
+
+       if (val > 1)
+               return -EINVAL;
+
+       pm_async_enabled = val;
+       return n;
 }
 
+power_attr(pm_async);
+
+#ifdef CONFIG_PM_DEBUG
+int pm_test_level = TEST_NONE;
+
 static const char * const pm_tests[__TEST_AFTER_LAST] = {
        [TEST_NONE] = "none",
        [TEST_CORE] = "core",
@@ -128,272 +131,9 @@ static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
 }
 
 power_attr(pm_test);
-#else /* !CONFIG_PM_DEBUG */
-static inline int suspend_test(int level) { return 0; }
-#endif /* !CONFIG_PM_DEBUG */
-
-
-#ifdef CONFIG_SUSPEND
-
-/* This is just an arbitrary number */
-#define FREE_PAGE_NUMBER (100)
-
-static struct platform_suspend_ops *suspend_ops;
-
-/**
- *     suspend_set_ops - Set the global suspend method table.
- *     @ops:   Pointer to ops structure.
- */
-
-void suspend_set_ops(struct platform_suspend_ops *ops)
-{
-       mutex_lock(&pm_mutex);
-       suspend_ops = ops;
-       mutex_unlock(&pm_mutex);
-}
-
-/**
- * suspend_valid_only_mem - generic memory-only valid callback
- *
- * Platform drivers that implement mem suspend only and only need
- * to check for that in their .valid callback can use this instead
- * of rolling their own .valid callback.
- */
-int suspend_valid_only_mem(suspend_state_t state)
-{
-       return state == PM_SUSPEND_MEM;
-}
-
-/**
- *     suspend_prepare - Do prep work before entering low-power state.
- *
- *     This is common code that is called for each state that we're entering.
- *     Run suspend notifiers, allocate a console and stop all processes.
- */
-static int suspend_prepare(void)
-{
-       int error;
-       unsigned int free_pages;
-
-       if (!suspend_ops || !suspend_ops->enter)
-               return -EPERM;
+#endif /* CONFIG_PM_DEBUG */
 
-       error = pm_notifier_call_chain(PM_SUSPEND_PREPARE);
-       if (error)
-               goto Finish;
-
-       pm_prepare_console();
-
-       if (freeze_processes()) {
-               error = -EAGAIN;
-               goto Thaw;
-       }
-
-       free_pages = global_page_state(NR_FREE_PAGES);
-       if (free_pages < FREE_PAGE_NUMBER) {
-               pr_debug("PM: free some memory\n");
-               shrink_all_memory(FREE_PAGE_NUMBER - free_pages);
-               if (nr_free_pages() < FREE_PAGE_NUMBER) {
-                       error = -ENOMEM;
-                       printk(KERN_ERR "PM: No enough memory\n");
-               }
-       }
-       if (!error)
-               return 0;
-
- Thaw:
-       thaw_processes();
-       pm_restore_console();
- Finish:
-       pm_notifier_call_chain(PM_POST_SUSPEND);
-       return error;
-}
-
-/* default implementation */
-void __attribute__ ((weak)) arch_suspend_disable_irqs(void)
-{
-       local_irq_disable();
-}
-
-/* default implementation */
-void __attribute__ ((weak)) arch_suspend_enable_irqs(void)
-{
-       local_irq_enable();
-}
-
-/**
- *     suspend_enter - enter the desired system sleep state.
- *     @state:         state to enter
- *
- *     This function should be called after devices have been suspended.
- */
-static int suspend_enter(suspend_state_t state)
-{
-       int error = 0;
-
-       arch_suspend_disable_irqs();
-       BUG_ON(!irqs_disabled());
-
-       if ((error = device_power_down(PMSG_SUSPEND))) {
-               printk(KERN_ERR "Some devices failed to power down\n");
-               goto Done;
-       }
-
-       if (!suspend_test(TEST_CORE))
-               error = suspend_ops->enter(state);
-
-       device_power_up();
- Done:
-       arch_suspend_enable_irqs();
-       BUG_ON(irqs_disabled());
-       return error;
-}
-
-/**
- *     suspend_devices_and_enter - suspend devices and enter the desired system
- *                                 sleep state.
- *     @state:           state to enter
- */
-int suspend_devices_and_enter(suspend_state_t state)
-{
-       int error;
-
-       if (!suspend_ops)
-               return -ENOSYS;
-
-       if (suspend_ops->set_target) {
-               error = suspend_ops->set_target(state);
-               if (error)
-                       return error;
-       }
-       suspend_console();
-       error = device_suspend(PMSG_SUSPEND);
-       if (error) {
-               printk(KERN_ERR "Some devices failed to suspend\n");
-               goto Resume_console;
-       }
-
-       if (suspend_test(TEST_DEVICES))
-               goto Resume_devices;
-
-       if (suspend_ops->prepare) {
-               error = suspend_ops->prepare();
-               if (error)
-                       goto Resume_devices;
-       }
-
-       if (suspend_test(TEST_PLATFORM))
-               goto Finish;
-
-       error = disable_nonboot_cpus();
-       if (!error && !suspend_test(TEST_CPUS))
-               suspend_enter(state);
-
-       enable_nonboot_cpus();
- Finish:
-       if (suspend_ops->finish)
-               suspend_ops->finish();
- Resume_devices:
-       device_resume();
- Resume_console:
-       resume_console();
-       return error;
-}
-
-/**
- *     suspend_finish - Do final work before exiting suspend sequence.
- *
- *     Call platform code to clean up, restart processes, and free the 
- *     console that we've allocated. This is not called for suspend-to-disk.
- */
-static void suspend_finish(void)
-{
-       thaw_processes();
-       pm_restore_console();
-       pm_notifier_call_chain(PM_POST_SUSPEND);
-}
-
-
-
-
-static const char * const pm_states[PM_SUSPEND_MAX] = {
-       [PM_SUSPEND_STANDBY]    = "standby",
-       [PM_SUSPEND_MEM]        = "mem",
-};
-
-static inline int valid_state(suspend_state_t state)
-{
-       /* All states need lowlevel support and need to be valid
-        * to the lowlevel implementation, no valid callback
-        * implies that none are valid. */
-       if (!suspend_ops || !suspend_ops->valid || !suspend_ops->valid(state))
-               return 0;
-       return 1;
-}
-
-
-/**
- *     enter_state - Do common work of entering low-power state.
- *     @state:         pm_state structure for state we're entering.
- *
- *     Make sure we're the only ones trying to enter a sleep state. Fail
- *     if someone has beat us to it, since we don't want anything weird to
- *     happen when we wake up.
- *     Then, do the setup for suspend, enter the state, and cleaup (after
- *     we've woken up).
- */
-static int enter_state(suspend_state_t state)
-{
-       int error;
-
-       if (!valid_state(state))
-               return -ENODEV;
-
-       if (!mutex_trylock(&pm_mutex))
-               return -EBUSY;
-
-       printk("Syncing filesystems ... ");
-       sys_sync();
-       printk("done.\n");
-
-       pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]);
-       error = suspend_prepare();
-       if (error)
-               goto Unlock;
-
-       if (suspend_test(TEST_FREEZER))
-               goto Finish;
-
-       pr_debug("PM: Entering %s sleep\n", pm_states[state]);
-       error = suspend_devices_and_enter(state);
-
- Finish:
-       pr_debug("PM: Finishing wakeup.\n");
-       suspend_finish();
- Unlock:
-       mutex_unlock(&pm_mutex);
-       return error;
-}
-
-
-/**
- *     pm_suspend - Externally visible function for suspending system.
- *     @state:         Enumerated value of state to enter.
- *
- *     Determine whether or not value is within range, get state 
- *     structure, and enter (above).
- */
-
-int pm_suspend(suspend_state_t state)
-{
-       if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX)
-               return enter_state(state);
-       return -EINVAL;
-}
-
-EXPORT_SYMBOL(pm_suspend);
-
-#endif /* CONFIG_SUSPEND */
+#endif /* CONFIG_PM_SLEEP */
 
 struct kobject *power_kobj;
 
@@ -407,7 +147,6 @@ struct kobject *power_kobj;
  *     store() accepts one of those strings, translates it into the 
  *     proper enumerated value, and initiates a suspend transition.
  */
-
 static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
                          char *buf)
 {
@@ -465,6 +204,60 @@ static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
 
 power_attr(state);
 
+#ifdef CONFIG_PM_SLEEP
+/*
+ * The 'wakeup_count' attribute, along with the functions defined in
+ * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
+ * handled in a non-racy way.
+ *
+ * If a wakeup event occurs when the system is in a sleep state, it simply is
+ * woken up.  In turn, if an event that would wake the system up from a sleep
+ * state occurs when it is undergoing a transition to that sleep state, the
+ * transition should be aborted.  Moreover, if such an event occurs when the
+ * system is in the working state, an attempt to start a transition to the
+ * given sleep state should fail during certain period after the detection of
+ * the event.  Using the 'state' attribute alone is not sufficient to satisfy
+ * these requirements, because a wakeup event may occur exactly when 'state'
+ * is being written to and may be delivered to user space right before it is
+ * frozen, so the event will remain only partially processed until the system is
+ * woken up by another event.  In particular, it won't cause the transition to
+ * a sleep state to be aborted.
+ *
+ * This difficulty may be overcome if user space uses 'wakeup_count' before
+ * writing to 'state'.  It first should read from 'wakeup_count' and store
+ * the read value.  Then, after carrying out its own preparations for the system
+ * transition to a sleep state, it should write the stored value to
+ * 'wakeup_count'.  If that fails, at least one wakeup event has occured since
+ * 'wakeup_count' was read and 'state' should not be written to.  Otherwise, it
+ * is allowed to write to 'state', but the transition will be aborted if there
+ * are any wakeup events detected after 'wakeup_count' was written to.
+ */
+
+static ssize_t wakeup_count_show(struct kobject *kobj,
+                               struct kobj_attribute *attr,
+                               char *buf)
+{
+       unsigned int val;
+
+       return pm_get_wakeup_count(&val) ? sprintf(buf, "%u\n", val) : -EINTR;
+}
+
+static ssize_t wakeup_count_store(struct kobject *kobj,
+                               struct kobj_attribute *attr,
+                               const char *buf, size_t n)
+{
+       unsigned int val;
+
+       if (sscanf(buf, "%u", &val) == 1) {
+               if (pm_save_wakeup_count(val))
+                       return n;
+       }
+       return -EINVAL;
+}
+
+power_attr(wakeup_count);
+#endif /* CONFIG_PM_SLEEP */
+
 #ifdef CONFIG_PM_TRACE
 int pm_trace_enabled;
 
@@ -488,16 +281,38 @@ pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
 }
 
 power_attr(pm_trace);
+
+static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
+                                      struct kobj_attribute *attr,
+                                      char *buf)
+{
+       return show_trace_dev_match(buf, PAGE_SIZE);
+}
+
+static ssize_t
+pm_trace_dev_match_store(struct kobject *kobj, struct kobj_attribute *attr,
+                        const char *buf, size_t n)
+{
+       return -EINVAL;
+}
+
+power_attr(pm_trace_dev_match);
+
 #endif /* CONFIG_PM_TRACE */
 
 static struct attribute * g[] = {
        &state_attr.attr,
 #ifdef CONFIG_PM_TRACE
        &pm_trace_attr.attr,
+       &pm_trace_dev_match_attr.attr,
 #endif
+#ifdef CONFIG_PM_SLEEP
+       &pm_async_attr.attr,
+       &wakeup_count_attr.attr,
 #ifdef CONFIG_PM_DEBUG
        &pm_test_attr.attr,
 #endif
+#endif
        NULL,
 };
 
@@ -505,9 +320,26 @@ static struct attribute_group attr_group = {
        .attrs = g,
 };
 
+#ifdef CONFIG_PM_RUNTIME
+struct workqueue_struct *pm_wq;
+EXPORT_SYMBOL_GPL(pm_wq);
+
+static int __init pm_start_workqueue(void)
+{
+       pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
+
+       return pm_wq ? 0 : -ENOMEM;
+}
+#else
+static inline int pm_start_workqueue(void) { return 0; }
+#endif
 
 static int __init pm_init(void)
 {
+       int error = pm_start_workqueue();
+       if (error)
+               return error;
+       hibernate_image_size_init();
        power_kobj = kobject_create_and_add("power", NULL);
        if (!power_kobj)
                return -ENOMEM;