diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/power/Kconfig | 6 | ||||
| -rw-r--r-- | kernel/power/Makefile | 6 | ||||
| -rw-r--r-- | kernel/power/disk.c | 35 | ||||
| -rw-r--r-- | kernel/power/main.c | 16 | ||||
| -rw-r--r-- | kernel/power/smp.c | 89 | ||||
| -rw-r--r-- | kernel/power/swsusp.c | 2 |
6 files changed, 72 insertions, 82 deletions
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index 696387ffe49..fdb37763650 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -28,7 +28,7 @@ config PM_DEBUG config SOFTWARE_SUSPEND bool "Software Suspend (EXPERIMENTAL)" - depends on EXPERIMENTAL && PM && SWAP + depends on EXPERIMENTAL && PM && SWAP && (SUSPEND_SMP || !SMP) ---help--- Enable the possibility of suspending the machine. It doesn't need APM. @@ -72,3 +72,7 @@ config PM_STD_PARTITION suspended image to. It will simply pick the first available swap device. +config SUSPEND_SMP + bool + depends on HOTPLUG_CPU && X86 && PM + default y diff --git a/kernel/power/Makefile b/kernel/power/Makefile index fbdc634135a..2f438d0eaa1 100644 --- a/kernel/power/Makefile +++ b/kernel/power/Makefile @@ -3,9 +3,9 @@ ifeq ($(CONFIG_PM_DEBUG),y) EXTRA_CFLAGS += -DDEBUG endif -swsusp-smp-$(CONFIG_SMP) += smp.o - obj-y := main.o process.o console.o pm.o -obj-$(CONFIG_SOFTWARE_SUSPEND) += swsusp.o $(swsusp-smp-y) disk.o +obj-$(CONFIG_SOFTWARE_SUSPEND) += swsusp.o disk.o + +obj-$(CONFIG_SUSPEND_SMP) += smp.o obj-$(CONFIG_MAGIC_SYSRQ) += poweroff.o diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 02b6764034d..fb8de63c291 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -117,8 +117,8 @@ static void finish(void) { device_resume(); platform_finish(); - enable_nonboot_cpus(); thaw_processes(); + enable_nonboot_cpus(); pm_restore_console(); } @@ -131,28 +131,35 @@ static int prepare_processes(void) sys_sync(); + disable_nonboot_cpus(); + if (freeze_processes()) { error = -EBUSY; - return error; + goto thaw; } if (pm_disk_mode == PM_DISK_PLATFORM) { if (pm_ops && pm_ops->prepare) { if ((error = pm_ops->prepare(PM_SUSPEND_DISK))) - return error; + goto thaw; } } /* Free memory before shutting down devices. */ free_some_memory(); - return 0; +thaw: + thaw_processes(); + enable_nonboot_cpus(); + pm_restore_console(); + return error; } static void unprepare_processes(void) { - enable_nonboot_cpus(); + platform_finish(); thaw_processes(); + enable_nonboot_cpus(); pm_restore_console(); } @@ -160,15 +167,9 @@ static int prepare_devices(void) { int error; - disable_nonboot_cpus(); - if ((error = device_suspend(PMSG_FREEZE))) { + if ((error = device_suspend(PMSG_FREEZE))) printk("Some devices failed to suspend\n"); - platform_finish(); - enable_nonboot_cpus(); - return error; - } - - return 0; + return error; } /** @@ -185,9 +186,9 @@ int pm_suspend_disk(void) int error; error = prepare_processes(); - if (!error) { - error = prepare_devices(); - } + if (error) + return error; + error = prepare_devices(); if (error) { unprepare_processes(); @@ -250,7 +251,7 @@ static int software_resume(void) if ((error = prepare_processes())) { swsusp_close(); - goto Cleanup; + goto Done; } pr_debug("PM: Reading swsusp image.\n"); diff --git a/kernel/power/main.c b/kernel/power/main.c index 4cdebc972ff..c94cb9e9509 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -55,6 +55,13 @@ static int suspend_prepare(suspend_state_t state) pm_prepare_console(); + disable_nonboot_cpus(); + + if (num_online_cpus() != 1) { + error = -EPERM; + goto Enable_cpu; + } + if (freeze_processes()) { error = -EAGAIN; goto Thaw; @@ -75,6 +82,8 @@ 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; } @@ -113,6 +122,7 @@ static void suspend_finish(suspend_state_t state) if (pm_ops && pm_ops->finish) pm_ops->finish(state); thaw_processes(); + enable_nonboot_cpus(); pm_restore_console(); } @@ -150,12 +160,6 @@ 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; diff --git a/kernel/power/smp.c b/kernel/power/smp.c index 457c2302ed4..bbe23079c62 100644 --- a/kernel/power/smp.c +++ b/kernel/power/smp.c @@ -13,73 +13,52 @@ #include <linux/interrupt.h> #include <linux/suspend.h> #include <linux/module.h> +#include <linux/cpu.h> #include <asm/atomic.h> #include <asm/tlbflush.h> -static atomic_t cpu_counter, freeze; - - -static void smp_pause(void * data) -{ - struct saved_context ctxt; - __save_processor_state(&ctxt); - printk("Sleeping in:\n"); - dump_stack(); - atomic_inc(&cpu_counter); - while (atomic_read(&freeze)) { - /* FIXME: restore takes place at random piece inside this. - This should probably be written in assembly, and - preserve general-purpose registers, too - - What about stack? We may need to move to new stack here. - - This should better be ran with interrupts disabled. - */ - cpu_relax(); - barrier(); - } - atomic_dec(&cpu_counter); - __restore_processor_state(&ctxt); -} - -static cpumask_t oldmask; +/* This is protected by pm_sem semaphore */ +static cpumask_t frozen_cpus; void disable_nonboot_cpus(void) { - oldmask = current->cpus_allowed; - set_cpus_allowed(current, cpumask_of_cpu(0)); - printk("Freezing CPUs (at %d)", raw_smp_processor_id()); - current->state = TASK_INTERRUPTIBLE; - schedule_timeout(HZ); - printk("..."); - BUG_ON(raw_smp_processor_id() != 0); - - /* FIXME: for this to work, all the CPUs must be running - * "idle" thread (or we deadlock). Is that guaranteed? */ + int cpu, error; - atomic_set(&cpu_counter, 0); - atomic_set(&freeze, 1); - smp_call_function(smp_pause, NULL, 0, 0); - while (atomic_read(&cpu_counter) < (num_online_cpus() - 1)) { - cpu_relax(); - barrier(); + error = 0; + cpus_clear(frozen_cpus); + printk("Freezing cpus ...\n"); + for_each_online_cpu(cpu) { + if (cpu == 0) + continue; + error = cpu_down(cpu); + if (!error) { + cpu_set(cpu, frozen_cpus); + printk("CPU%d is down\n", cpu); + continue; + } + printk("Error taking cpu %d down: %d\n", cpu, error); } - printk("ok\n"); + BUG_ON(smp_processor_id() != 0); + if (error) + panic("cpus not sleeping"); } void enable_nonboot_cpus(void) { - printk("Restarting CPUs"); - atomic_set(&freeze, 0); - while (atomic_read(&cpu_counter)) { - cpu_relax(); - barrier(); - } - printk("..."); - set_cpus_allowed(current, oldmask); - schedule(); - printk("ok\n"); + int cpu, error; + printk("Thawing cpus ...\n"); + for_each_cpu_mask(cpu, frozen_cpus) { + error = smp_prepare_cpu(cpu); + if (!error) + error = cpu_up(cpu); + if (!error) { + printk("CPU%d is up\n", cpu); + continue; + } + printk("Error taking cpu %d up: %d\n", cpu, error); + panic("Not enough cpus"); + } + cpus_clear(frozen_cpus); } - diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 53f9f8720ee..339b5c3735b 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -1193,8 +1193,10 @@ static const char * sanity_check(void) return "version"; if (strcmp(swsusp_info.uts.machine,system_utsname.machine)) return "machine"; +#if 0 if(swsusp_info.cpus != num_online_cpus()) return "number of cpus"; +#endif return NULL; } |