X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=kernel%2Fpower%2Fmain.c;h=ff3a6182f5f0df3fb479cbd56092dd0ee8e1ff2e;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=4cdebc972ff2a55c7fdac702dca0c36f81905558;hpb=f7f1b0f1e2fbadeab12d24236000e778aa9b1ead;p=linux-2.6.git diff --git a/kernel/power/main.c b/kernel/power/main.c index 4cdebc972..ff3a6182f 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -8,6 +8,7 @@ * */ +#include #include #include #include @@ -15,14 +16,20 @@ #include #include #include - +#include +#include +#include +#include #include "power.h" -DECLARE_MUTEX(pm_sem); +/*This is just an arbitrary number */ +#define FREE_PAGE_NUMBER (100) + +DEFINE_MUTEX(pm_mutex); -struct pm_ops * pm_ops = NULL; -suspend_disk_method_t pm_disk_mode = PM_DISK_SHUTDOWN; +struct pm_ops *pm_ops; +suspend_disk_method_t pm_disk_mode = PM_DISK_PLATFORM; /** * pm_set_ops - Set the global power method table. @@ -31,9 +38,9 @@ suspend_disk_method_t pm_disk_mode = PM_DISK_SHUTDOWN; void pm_set_ops(struct pm_ops * ops) { - down(&pm_sem); + mutex_lock(&pm_mutex); pm_ops = ops; - up(&pm_sem); + mutex_unlock(&pm_mutex); } @@ -48,23 +55,39 @@ 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; } + suspend_console(); if ((error = device_suspend(PMSG_SUSPEND))) { printk(KERN_ERR "Some devices failed to suspend\n"); goto Finish; @@ -75,12 +98,14 @@ static int suspend_prepare(suspend_state_t state) 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; @@ -110,22 +135,37 @@ 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(); } -static 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. @@ -142,7 +182,9 @@ static int enter_state(suspend_state_t state) { int error; - if (down_trylock(&pm_sem)) + if (!valid_state(state)) + return -ENODEV; + if (!mutex_trylock(&pm_mutex)) return -EBUSY; if (state == PM_SUSPEND_DISK) { @@ -150,12 +192,6 @@ 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 %s sleep\n", pm_states[state]); if ((error = suspend_prepare(state))) goto Unlock; @@ -166,7 +202,7 @@ static int enter_state(suspend_state_t state) pr_debug("PM: Finishing wakeup.\n"); suspend_finish(state); Unlock: - up(&pm_sem); + mutex_unlock(&pm_mutex); return error; } @@ -190,12 +226,12 @@ 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; } - +EXPORT_SYMBOL(pm_suspend); decl_subsys(power,NULL,NULL); @@ -217,8 +253,8 @@ 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); @@ -227,7 +263,7 @@ 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; @@ -239,7 +275,7 @@ 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; @@ -248,10 +284,39 @@ static ssize_t state_store(struct subsystem * subsys, const char * buf, size_t n power_attr(state); +#ifdef CONFIG_PM_TRACE +int pm_trace_enabled; + +static ssize_t pm_trace_show(struct subsystem * subsys, char * buf) +{ + return sprintf(buf, "%d\n", pm_trace_enabled); +} + +static ssize_t +pm_trace_store(struct subsystem * subsys, const char * buf, size_t n) +{ + int val; + + if (sscanf(buf, "%d", &val) == 1) { + pm_trace_enabled = !!val; + return n; + } + return -EINVAL; +} + +power_attr(pm_trace); + +static struct attribute * g[] = { + &state_attr.attr, + &pm_trace_attr.attr, + NULL, +}; +#else static struct attribute * g[] = { &state_attr.attr, NULL, }; +#endif /* CONFIG_PM_TRACE */ static struct attribute_group attr_group = { .attrs = g,