X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=kernel%2Fpower%2Fmain.c;h=4d403323a7bb709c6384f7a5085f3cdb0872c360;hb=e0ff8aa1acd079b70e796571917ae0449b7c465b;hp=0f78207cfb5737caed34784dd38264441a7eff2b;hpb=6a77f38946aaee1cd85eeec6cf4229b204c15071;p=linux-2.6.git diff --git a/kernel/power/main.c b/kernel/power/main.c index 0f78207cf..4d403323a 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -15,13 +15,17 @@ #include #include #include - +#include +#include #include "power.h" +/*This is just an arbitrary number */ +#define FREE_PAGE_NUMBER (100) + DECLARE_MUTEX(pm_sem); -struct pm_ops * pm_ops = NULL; +struct pm_ops *pm_ops; suspend_disk_method_t pm_disk_mode = PM_DISK_SHUTDOWN; /** @@ -48,45 +52,67 @@ void pm_set_ops(struct pm_ops * ops) static int suspend_prepare(suspend_state_t state) { - int error = 0; + int error; + unsigned int free_pages; if (!pm_ops || !pm_ops->enter) return -EPERM; pm_prepare_console(); + error = disable_nonboot_cpus(); + if (error) + 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; } - if ((error = device_suspend(PMSG_SUSPEND))) + suspend_console(); + if ((error = device_suspend(PMSG_SUSPEND))) { + printk(KERN_ERR "Some devices failed to suspend\n"); goto Finish; + } return 0; Finish: if (pm_ops->finish) pm_ops->finish(state); Thaw: thaw_processes(); + Enable_cpu: + enable_nonboot_cpus(); pm_restore_console(); return error; } -static int suspend_enter(suspend_state_t state) +int suspend_enter(suspend_state_t state) { int error = 0; unsigned long flags; local_irq_save(flags); - if ((error = device_power_down(PMSG_SUSPEND))) + if ((error = device_power_down(PMSG_SUSPEND))) { + printk(KERN_ERR "Some devices failed to power down\n"); goto Done; + } error = pm_ops->enter(state); device_power_up(); Done: @@ -106,22 +132,37 @@ static int suspend_enter(suspend_state_t state) static void suspend_finish(suspend_state_t state) { device_resume(); + resume_console(); + thaw_processes(); + enable_nonboot_cpus(); if (pm_ops && pm_ops->finish) pm_ops->finish(state); - thaw_processes(); pm_restore_console(); } -char * pm_states[] = { +static const char * const pm_states[PM_SUSPEND_MAX] = { [PM_SUSPEND_STANDBY] = "standby", [PM_SUSPEND_MEM] = "mem", +#ifdef CONFIG_SOFTWARE_SUSPEND [PM_SUSPEND_DISK] = "disk", - NULL, +#endif }; +static inline int valid_state(suspend_state_t state) +{ + /* Suspend-to-disk does not really need low-level support. + * It can work with reboot if needed. */ + if (state == PM_SUSPEND_DISK) + return 1; + + if (pm_ops && pm_ops->valid && !pm_ops->valid(state)) + return 0; + return 1; +} + /** * enter_state - Do common work of entering low-power state. @@ -138,6 +179,8 @@ static int enter_state(suspend_state_t state) { int error; + if (!valid_state(state)) + return -ENODEV; if (down_trylock(&pm_sem)) return -EBUSY; @@ -146,20 +189,14 @@ static int enter_state(suspend_state_t state) 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 suspend\n"); + pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); if ((error = suspend_prepare(state))) goto Unlock; - pr_debug("PM: Entering state.\n"); + pr_debug("PM: Entering %s sleep\n", pm_states[state]); error = suspend_enter(state); - pr_debug("PM: Finishing up.\n"); + pr_debug("PM: Finishing wakeup.\n"); suspend_finish(state); Unlock: up(&pm_sem); @@ -186,7 +223,7 @@ int software_suspend(void) 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; } @@ -213,8 +250,8 @@ static ssize_t state_show(struct subsystem * subsys, char * buf) char * s = buf; for (i = 0; i < PM_SUSPEND_MAX; i++) { - if (pm_states[i]) - s += sprintf(s,"%s ",pm_states[i]); + if (pm_states[i] && valid_state(i)) + s += sprintf(s,"%s ", pm_states[i]); } s += sprintf(s,"\n"); return (s - buf); @@ -223,7 +260,7 @@ static ssize_t state_show(struct subsystem * subsys, char * buf) static ssize_t state_store(struct subsystem * subsys, const char * buf, size_t n) { suspend_state_t state = PM_SUSPEND_STANDBY; - char ** s; + const char * const *s; char *p; int error; int len; @@ -235,7 +272,7 @@ static ssize_t state_store(struct subsystem * subsys, const char * buf, size_t n if (*s && !strncmp(buf, *s, len)) break; } - if (*s) + if (state < PM_SUSPEND_MAX && *s) error = enter_state(state); else error = -EINVAL;