Suspend: Testing facility (rev. 2)

Introduce sysfs attribute /sys/power/pm_test allowing one to test the suspend
core code.  Namely, writing one of the strings:

freezer
devices
platform
processors
core

to this file causes the suspend code to work in one of the test modes defined as
follows:

freezer
- test the freezing of processes

devices
- test the freezing of processes and suspending of devices

platform
- test the freezing of processes, suspending of devices and platform global
  control methods(*)

processors
- test the freezing of processes, suspending of devices, platform global
  control methods and the disabling of nonboot CPUs

core
- test the freezing of processes, suspending of devices, platform global
  control methods, the disabling of nonboot CPUs and suspending of
  platform/system devices

(*) These are ACPI global control methods on ACPI systems

Then, if a suspend is started by normal means, the suspend core will perform
its normal operations up to the point indicated by given test level.  Next, it
will wait for 5 seconds and carry out the resume operations needed to transition
the system back to the fully functional state.

Writing "none" to /sys/power/pm_test turns the testing off.

When open for reading, /sys/power/pm_test contains a space-separated list of all
available tests (including "none" that represents the normal functionality) in
which the current test level is indicated by square brackets.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Rafael J. Wysocki 2007-11-19 23:41:19 +01:00 committed by Len Brown
parent c3e94d899c
commit 0e7d56e3d9
2 changed files with 117 additions and 9 deletions

View File

@ -31,6 +31,79 @@ DEFINE_MUTEX(pm_mutex);
unsigned int pm_flags;
EXPORT_SYMBOL(pm_flags);
#ifdef CONFIG_PM_DEBUG
int pm_test_level = TEST_NONE;
static int suspend_test(int level)
{
if (pm_test_level == level) {
printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n");
mdelay(5000);
return 1;
}
return 0;
}
static const char * const pm_tests[__TEST_AFTER_LAST] = {
[TEST_NONE] = "none",
[TEST_CORE] = "core",
[TEST_CPUS] = "processors",
[TEST_PLATFORM] = "platform",
[TEST_DEVICES] = "devices",
[TEST_FREEZER] = "freezer",
};
static ssize_t pm_test_show(struct kset *kset, char *buf)
{
char *s = buf;
int level;
for (level = TEST_FIRST; level <= TEST_MAX; level++)
if (pm_tests[level]) {
if (level == pm_test_level)
s += sprintf(s, "[%s] ", pm_tests[level]);
else
s += sprintf(s, "%s ", pm_tests[level]);
}
if (s != buf)
/* convert the last space to a newline */
*(s-1) = '\n';
return (s - buf);
}
static ssize_t pm_test_store(struct kset *kset, const char *buf, size_t n)
{
const char * const *s;
int level;
char *p;
int len;
int error = -EINVAL;
p = memchr(buf, '\n', n);
len = p ? p - buf : n;
mutex_lock(&pm_mutex);
level = TEST_FIRST;
for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
pm_test_level = level;
error = 0;
break;
}
mutex_unlock(&pm_mutex);
return error ? error : n;
}
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 */
@ -136,7 +209,10 @@ static int suspend_enter(suspend_state_t state)
printk(KERN_ERR "Some devices failed to power down\n");
goto Done;
}
error = suspend_ops->enter(state);
if (!suspend_test(TEST_CORE))
error = suspend_ops->enter(state);
device_power_up();
Done:
arch_suspend_enable_irqs();
@ -167,16 +243,25 @@ int suspend_devices_and_enter(suspend_state_t state)
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)
if (!error && !suspend_test(TEST_CPUS))
suspend_enter(state);
enable_nonboot_cpus();
Finish:
if (suspend_ops->finish)
suspend_ops->finish();
Resume_devices:
@ -243,12 +328,17 @@ static int enter_state(suspend_state_t state)
printk("done.\n");
pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]);
if ((error = suspend_prepare()))
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:
@ -369,18 +459,18 @@ pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
}
power_attr(pm_trace);
#endif /* CONFIG_PM_TRACE */
static struct attribute * g[] = {
&state_attr.attr,
#ifdef CONFIG_PM_TRACE
&pm_trace_attr.attr,
#endif
#ifdef CONFIG_PM_DEBUG
&pm_test_attr.attr,
#endif
NULL,
};
#else
static struct attribute * g[] = {
&state_attr.attr,
NULL,
};
#endif /* CONFIG_PM_TRACE */
static struct attribute_group attr_group = {
.attrs = g,

View File

@ -188,3 +188,21 @@ int restore_highmem(void);
static inline unsigned int count_highmem_pages(void) { return 0; }
static inline int restore_highmem(void) { return 0; }
#endif
/*
* Suspend test levels
*/
enum {
/* keep first */
TEST_NONE,
TEST_CORE,
TEST_CPUS,
TEST_PLATFORM,
TEST_DEVICES,
TEST_FREEZER,
/* keep last */
__TEST_AFTER_LAST
};
#define TEST_FIRST TEST_NONE
#define TEST_MAX (__TEST_AFTER_LAST - 1)