diff options
Diffstat (limited to 'arch/x86/power/cpu.c')
| -rw-r--r-- | arch/x86/power/cpu.c | 126 |
1 files changed, 109 insertions, 17 deletions
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c index 87bb35e34ef..424f4c97a44 100644 --- a/arch/x86/power/cpu.c +++ b/arch/x86/power/cpu.c @@ -9,7 +9,9 @@ */ #include <linux/suspend.h> +#include <linux/export.h> #include <linux/smp.h> +#include <linux/perf_event.h> #include <asm/pgtable.h> #include <asm/proto.h> @@ -19,18 +21,16 @@ #include <asm/xcr.h> #include <asm/suspend.h> #include <asm/debugreg.h> +#include <asm/fpu-internal.h> /* pcntxt_mask */ +#include <asm/cpu.h> #ifdef CONFIG_X86_32 -static struct saved_context saved_context; - -unsigned long saved_context_ebx; -unsigned long saved_context_esp, saved_context_ebp; -unsigned long saved_context_esi, saved_context_edi; -unsigned long saved_context_eflags; -#else -/* CONFIG_X86_64 */ -struct saved_context saved_context; +__visible unsigned long saved_context_ebx; +__visible unsigned long saved_context_esp, saved_context_ebp; +__visible unsigned long saved_context_esi, saved_context_edi; +__visible unsigned long saved_context_eflags; #endif +struct saved_context saved_context; /** * __save_processor_state - save CPU registers before creating a @@ -58,13 +58,20 @@ static void __save_processor_state(struct saved_context *ctxt) * descriptor tables */ #ifdef CONFIG_X86_32 - store_gdt(&ctxt->gdt); store_idt(&ctxt->idt); #else /* CONFIG_X86_64 */ - store_gdt((struct desc_ptr *)&ctxt->gdt_limit); store_idt((struct desc_ptr *)&ctxt->idt_limit); #endif + /* + * We save it here, but restore it only in the hibernate case. + * For ACPI S3 resume, this is loaded via 'early_gdt_desc' in 64-bit + * mode in "secondary_startup_64". In 32-bit mode it is done via + * 'pmode_gdt' in wakeup_start. + */ + ctxt->gdt_desc.size = GDT_SIZE - 1; + ctxt->gdt_desc.address = (unsigned long)get_cpu_gdt_table(smp_processor_id()); + store_tr(ctxt->tr); /* XMM0..XMM15 should be handled by kernel_fpu_begin(). */ @@ -113,7 +120,7 @@ static void __save_processor_state(struct saved_context *ctxt) void save_processor_state(void) { __save_processor_state(&saved_context); - save_sched_clock_state(); + x86_platform.save_sched_clock_state(); } #ifdef CONFIG_X86_32 EXPORT_SYMBOL(save_processor_state); @@ -131,7 +138,10 @@ static void fix_processor_context(void) { int cpu = smp_processor_id(); struct tss_struct *t = &per_cpu(init_tss, cpu); - +#ifdef CONFIG_X86_64 + struct desc_struct *desc = get_cpu_gdt_table(cpu); + tss_desc tss; +#endif set_tss_desc(cpu, t); /* * This just modifies memory; should not be * necessary. But... This is necessary, because @@ -140,7 +150,9 @@ static void fix_processor_context(void) */ #ifdef CONFIG_X86_64 - get_cpu_gdt_table(cpu)[GDT_ENTRY_TSS].type = 9; + memcpy(&tss, &desc[GDT_ENTRY_TSS], sizeof(tss_desc)); + tss.type = 0x9; /* The available 64-bit TSS (see AMD vol 2, pg 91 */ + write_gdt_entry(desc, GDT_ENTRY_TSS, &tss, DESC_TSS); syscall_init(); /* This sets MSR_*STAR and related */ #endif @@ -179,11 +191,9 @@ static void __restore_processor_state(struct saved_context *ctxt) * ltr is done i fix_processor_context(). */ #ifdef CONFIG_X86_32 - load_gdt(&ctxt->gdt); load_idt(&ctxt->idt); #else /* CONFIG_X86_64 */ - load_gdt((const struct desc_ptr *)&ctxt->gdt_limit); load_idt((const struct desc_ptr *)&ctxt->idt_limit); #endif @@ -223,15 +233,97 @@ static void __restore_processor_state(struct saved_context *ctxt) fix_processor_context(); do_fpu_end(); + x86_platform.restore_sched_clock_state(); mtrr_bp_restore(); + perf_restore_debug_store(); } /* Needed by apm.c */ void restore_processor_state(void) { __restore_processor_state(&saved_context); - restore_sched_clock_state(); } #ifdef CONFIG_X86_32 EXPORT_SYMBOL(restore_processor_state); #endif + +/* + * When bsp_check() is called in hibernate and suspend, cpu hotplug + * is disabled already. So it's unnessary to handle race condition between + * cpumask query and cpu hotplug. + */ +static int bsp_check(void) +{ + if (cpumask_first(cpu_online_mask) != 0) { + pr_warn("CPU0 is offline.\n"); + return -ENODEV; + } + + return 0; +} + +static int bsp_pm_callback(struct notifier_block *nb, unsigned long action, + void *ptr) +{ + int ret = 0; + + switch (action) { + case PM_SUSPEND_PREPARE: + case PM_HIBERNATION_PREPARE: + ret = bsp_check(); + break; +#ifdef CONFIG_DEBUG_HOTPLUG_CPU0 + case PM_RESTORE_PREPARE: + /* + * When system resumes from hibernation, online CPU0 because + * 1. it's required for resume and + * 2. the CPU was online before hibernation + */ + if (!cpu_online(0)) + _debug_hotplug_cpu(0, 1); + break; + case PM_POST_RESTORE: + /* + * When a resume really happens, this code won't be called. + * + * This code is called only when user space hibernation software + * prepares for snapshot device during boot time. So we just + * call _debug_hotplug_cpu() to restore to CPU0's state prior to + * preparing the snapshot device. + * + * This works for normal boot case in our CPU0 hotplug debug + * mode, i.e. CPU0 is offline and user mode hibernation + * software initializes during boot time. + * + * If CPU0 is online and user application accesses snapshot + * device after boot time, this will offline CPU0 and user may + * see different CPU0 state before and after accessing + * the snapshot device. But hopefully this is not a case when + * user debugging CPU0 hotplug. Even if users hit this case, + * they can easily online CPU0 back. + * + * To simplify this debug code, we only consider normal boot + * case. Otherwise we need to remember CPU0's state and restore + * to that state and resolve racy conditions etc. + */ + _debug_hotplug_cpu(0, 0); + break; +#endif + default: + break; + } + return notifier_from_errno(ret); +} + +static int __init bsp_pm_check_init(void) +{ + /* + * Set this bsp_pm_callback as lower priority than + * cpu_hotplug_pm_callback. So cpu_hotplug_pm_callback will be called + * earlier to disable cpu hotplug before bsp online check. + */ + pm_notifier(bsp_pm_callback, -INT_MAX); + return 0; +} + +core_initcall(bsp_pm_check_init); |