#include "power.h"
+/*This is just an arbitrary number */
+#define FREE_PAGE_NUMBER (100)
+
DECLARE_MUTEX(pm_sem);
struct pm_ops * pm_ops = NULL;
static int suspend_prepare(suspend_state_t state)
{
int error = 0;
+ unsigned int free_pages;
if (!pm_ops || !pm_ops->enter)
return -EPERM;
pm_prepare_console();
+ disable_nonboot_cpus();
+
+ if (num_online_cpus() != 1) {
+ error = -EPERM;
+ goto Enable_cpu;
+ }
+
if (freeze_processes()) {
error = -EAGAIN;
goto Thaw;
}
+ if ((free_pages = nr_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");
+ goto Thaw;
+ }
+ }
+
if (pm_ops->prepare) {
if ((error = pm_ops->prepare(state)))
goto Thaw;
pm_ops->finish(state);
Thaw:
thaw_processes();
+ Enable_cpu:
+ enable_nonboot_cpus();
pm_restore_console();
return error;
}
if (pm_ops && pm_ops->finish)
pm_ops->finish(state);
thaw_processes();
+ enable_nonboot_cpus();
pm_restore_console();
}
goto Unlock;
}
- /* Suspend is hard to get right on SMP. */
- if (num_online_cpus() != 1) {
- error = -EPERM;
- goto Unlock;
- }
-
pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]);
if ((error = suspend_prepare(state)))
goto Unlock;
int pm_suspend(suspend_state_t state)
{
- if (state > PM_SUSPEND_ON && state < PM_SUSPEND_MAX)
+ if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX)
return enter_state(state);
return -EINVAL;
}