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Diffstat (limited to 'arch/i386/kernel/cpu/common.c')
-rw-r--r--arch/i386/kernel/cpu/common.c249
1 files changed, 179 insertions, 70 deletions
diff --git a/arch/i386/kernel/cpu/common.c b/arch/i386/kernel/cpu/common.c
index d9f3e3c31f0..1b34c56f812 100644
--- a/arch/i386/kernel/cpu/common.c
+++ b/arch/i386/kernel/cpu/common.c
@@ -18,14 +18,15 @@
#include <asm/apic.h>
#include <mach_apic.h>
#endif
+#include <asm/pda.h>
#include "cpu.h"
DEFINE_PER_CPU(struct Xgt_desc_struct, cpu_gdt_descr);
EXPORT_PER_CPU_SYMBOL(cpu_gdt_descr);
-DEFINE_PER_CPU(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
-EXPORT_PER_CPU_SYMBOL(cpu_16bit_stack);
+struct i386_pda *_cpu_pda[NR_CPUS] __read_mostly;
+EXPORT_SYMBOL(_cpu_pda);
static int cachesize_override __cpuinitdata = -1;
static int disable_x86_fxsr __cpuinitdata;
@@ -235,29 +236,14 @@ static int __cpuinit have_cpuid_p(void)
return flag_is_changeable_p(X86_EFLAGS_ID);
}
-/* Do minimum CPU detection early.
- Fields really needed: vendor, cpuid_level, family, model, mask, cache alignment.
- The others are not touched to avoid unwanted side effects.
-
- WARNING: this function is only called on the BP. Don't add code here
- that is supposed to run on all CPUs. */
-static void __init early_cpu_detect(void)
+void __init cpu_detect(struct cpuinfo_x86 *c)
{
- struct cpuinfo_x86 *c = &boot_cpu_data;
-
- c->x86_cache_alignment = 32;
-
- if (!have_cpuid_p())
- return;
-
/* Get vendor name */
cpuid(0x00000000, &c->cpuid_level,
(int *)&c->x86_vendor_id[0],
(int *)&c->x86_vendor_id[8],
(int *)&c->x86_vendor_id[4]);
- get_cpu_vendor(c, 1);
-
c->x86 = 4;
if (c->cpuid_level >= 0x00000001) {
u32 junk, tfms, cap0, misc;
@@ -274,6 +260,26 @@ static void __init early_cpu_detect(void)
}
}
+/* Do minimum CPU detection early.
+ Fields really needed: vendor, cpuid_level, family, model, mask, cache alignment.
+ The others are not touched to avoid unwanted side effects.
+
+ WARNING: this function is only called on the BP. Don't add code here
+ that is supposed to run on all CPUs. */
+static void __init early_cpu_detect(void)
+{
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+
+ c->x86_cache_alignment = 32;
+
+ if (!have_cpuid_p())
+ return;
+
+ cpu_detect(c);
+
+ get_cpu_vendor(c, 1);
+}
+
static void __cpuinit generic_identify(struct cpuinfo_x86 * c)
{
u32 tfms, xlvl;
@@ -308,6 +314,8 @@ static void __cpuinit generic_identify(struct cpuinfo_x86 * c)
#else
c->apicid = (ebx >> 24) & 0xFF;
#endif
+ if (c->x86_capability[0] & (1<<19))
+ c->x86_clflush_size = ((ebx >> 8) & 0xff) * 8;
} else {
/* Have CPUID level 0 only - unheard of */
c->x86 = 4;
@@ -372,6 +380,7 @@ void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
c->x86_vendor_id[0] = '\0'; /* Unset */
c->x86_model_id[0] = '\0'; /* Unset */
c->x86_max_cores = 1;
+ c->x86_clflush_size = 32;
memset(&c->x86_capability, 0, sizeof c->x86_capability);
if (!have_cpuid_p()) {
@@ -591,42 +600,24 @@ void __init early_cpu_init(void)
disable_pse = 1;
#endif
}
-/*
- * cpu_init() initializes state that is per-CPU. Some data is already
- * initialized (naturally) in the bootstrap process, such as the GDT
- * and IDT. We reload them nevertheless, this function acts as a
- * 'CPU state barrier', nothing should get across.
- */
-void __cpuinit cpu_init(void)
+
+/* Make sure %gs is initialized properly in idle threads */
+struct pt_regs * __devinit idle_regs(struct pt_regs *regs)
{
- int cpu = smp_processor_id();
- struct tss_struct * t = &per_cpu(init_tss, cpu);
- struct thread_struct *thread = &current->thread;
- struct desc_struct *gdt;
- __u32 stk16_off = (__u32)&per_cpu(cpu_16bit_stack, cpu);
- struct Xgt_desc_struct *cpu_gdt_descr = &per_cpu(cpu_gdt_descr, cpu);
+ memset(regs, 0, sizeof(struct pt_regs));
+ regs->xgs = __KERNEL_PDA;
+ return regs;
+}
- if (cpu_test_and_set(cpu, cpu_initialized)) {
- printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
- for (;;) local_irq_enable();
- }
- printk(KERN_INFO "Initializing CPU#%d\n", cpu);
+static __cpuinit int alloc_gdt(int cpu)
+{
+ struct Xgt_desc_struct *cpu_gdt_descr = &per_cpu(cpu_gdt_descr, cpu);
+ struct desc_struct *gdt;
+ struct i386_pda *pda;
- if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
- clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
- if (tsc_disable && cpu_has_tsc) {
- printk(KERN_NOTICE "Disabling TSC...\n");
- /**** FIX-HPA: DOES THIS REALLY BELONG HERE? ****/
- clear_bit(X86_FEATURE_TSC, boot_cpu_data.x86_capability);
- set_in_cr4(X86_CR4_TSD);
- }
+ gdt = (struct desc_struct *)cpu_gdt_descr->address;
+ pda = cpu_pda(cpu);
- /* The CPU hotplug case */
- if (cpu_gdt_descr->address) {
- gdt = (struct desc_struct *)cpu_gdt_descr->address;
- memset(gdt, 0, PAGE_SIZE);
- goto old_gdt;
- }
/*
* This is a horrible hack to allocate the GDT. The problem
* is that cpu_init() is called really early for the boot CPU
@@ -634,43 +625,130 @@ void __cpuinit cpu_init(void)
* CPUs, when bootmem will have gone away
*/
if (NODE_DATA(0)->bdata->node_bootmem_map) {
- gdt = (struct desc_struct *)alloc_bootmem_pages(PAGE_SIZE);
- /* alloc_bootmem_pages panics on failure, so no check */
+ BUG_ON(gdt != NULL || pda != NULL);
+
+ gdt = alloc_bootmem_pages(PAGE_SIZE);
+ pda = alloc_bootmem(sizeof(*pda));
+ /* alloc_bootmem(_pages) panics on failure, so no check */
+
memset(gdt, 0, PAGE_SIZE);
+ memset(pda, 0, sizeof(*pda));
} else {
- gdt = (struct desc_struct *)get_zeroed_page(GFP_KERNEL);
- if (unlikely(!gdt)) {
- printk(KERN_CRIT "CPU%d failed to allocate GDT\n", cpu);
- for (;;)
- local_irq_enable();
+ /* GDT and PDA might already have been allocated if
+ this is a CPU hotplug re-insertion. */
+ if (gdt == NULL)
+ gdt = (struct desc_struct *)get_zeroed_page(GFP_KERNEL);
+
+ if (pda == NULL)
+ pda = kmalloc_node(sizeof(*pda), GFP_KERNEL, cpu_to_node(cpu));
+
+ if (unlikely(!gdt || !pda)) {
+ free_pages((unsigned long)gdt, 0);
+ kfree(pda);
+ return 0;
}
}
-old_gdt:
+
+ cpu_gdt_descr->address = (unsigned long)gdt;
+ cpu_pda(cpu) = pda;
+
+ return 1;
+}
+
+/* Initial PDA used by boot CPU */
+struct i386_pda boot_pda = {
+ ._pda = &boot_pda,
+ .cpu_number = 0,
+ .pcurrent = &init_task,
+};
+
+static inline void set_kernel_gs(void)
+{
+ /* Set %gs for this CPU's PDA. Memory clobber is to create a
+ barrier with respect to any PDA operations, so the compiler
+ doesn't move any before here. */
+ asm volatile ("mov %0, %%gs" : : "r" (__KERNEL_PDA) : "memory");
+}
+
+/* Initialize the CPU's GDT and PDA. The boot CPU does this for
+ itself, but secondaries find this done for them. */
+__cpuinit int init_gdt(int cpu, struct task_struct *idle)
+{
+ struct Xgt_desc_struct *cpu_gdt_descr = &per_cpu(cpu_gdt_descr, cpu);
+ struct desc_struct *gdt;
+ struct i386_pda *pda;
+
+ /* For non-boot CPUs, the GDT and PDA should already have been
+ allocated. */
+ if (!alloc_gdt(cpu)) {
+ printk(KERN_CRIT "CPU%d failed to allocate GDT or PDA\n", cpu);
+ return 0;
+ }
+
+ gdt = (struct desc_struct *)cpu_gdt_descr->address;
+ pda = cpu_pda(cpu);
+
+ BUG_ON(gdt == NULL || pda == NULL);
+
/*
* Initialize the per-CPU GDT with the boot GDT,
* and set up the GDT descriptor:
*/
memcpy(gdt, cpu_gdt_table, GDT_SIZE);
+ cpu_gdt_descr->size = GDT_SIZE - 1;
- /* Set up GDT entry for 16bit stack */
- *(__u64 *)(&gdt[GDT_ENTRY_ESPFIX_SS]) |=
- ((((__u64)stk16_off) << 16) & 0x000000ffffff0000ULL) |
- ((((__u64)stk16_off) << 32) & 0xff00000000000000ULL) |
- (CPU_16BIT_STACK_SIZE - 1);
+ pack_descriptor((u32 *)&gdt[GDT_ENTRY_PDA].a,
+ (u32 *)&gdt[GDT_ENTRY_PDA].b,
+ (unsigned long)pda, sizeof(*pda) - 1,
+ 0x80 | DESCTYPE_S | 0x2, 0); /* present read-write data segment */
- cpu_gdt_descr->size = GDT_SIZE - 1;
- cpu_gdt_descr->address = (unsigned long)gdt;
+ memset(pda, 0, sizeof(*pda));
+ pda->_pda = pda;
+ pda->cpu_number = cpu;
+ pda->pcurrent = idle;
+
+ return 1;
+}
+
+/* Common CPU init for both boot and secondary CPUs */
+static void __cpuinit _cpu_init(int cpu, struct task_struct *curr)
+{
+ struct tss_struct * t = &per_cpu(init_tss, cpu);
+ struct thread_struct *thread = &curr->thread;
+ struct Xgt_desc_struct *cpu_gdt_descr = &per_cpu(cpu_gdt_descr, cpu);
+ /* Reinit these anyway, even if they've already been done (on
+ the boot CPU, this will transition from the boot gdt+pda to
+ the real ones). */
load_gdt(cpu_gdt_descr);
+ set_kernel_gs();
+
+ if (cpu_test_and_set(cpu, cpu_initialized)) {
+ printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
+ for (;;) local_irq_enable();
+ }
+
+ printk(KERN_INFO "Initializing CPU#%d\n", cpu);
+
+ if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
+ clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
+ if (tsc_disable && cpu_has_tsc) {
+ printk(KERN_NOTICE "Disabling TSC...\n");
+ /**** FIX-HPA: DOES THIS REALLY BELONG HERE? ****/
+ clear_bit(X86_FEATURE_TSC, boot_cpu_data.x86_capability);
+ set_in_cr4(X86_CR4_TSD);
+ }
+
load_idt(&idt_descr);
/*
* Set up and load the per-CPU TSS and LDT
*/
atomic_inc(&init_mm.mm_count);
- current->active_mm = &init_mm;
- BUG_ON(current->mm);
- enter_lazy_tlb(&init_mm, current);
+ curr->active_mm = &init_mm;
+ if (curr->mm)
+ BUG();
+ enter_lazy_tlb(&init_mm, curr);
load_esp0(t, thread);
set_tss_desc(cpu,t);
@@ -682,8 +760,8 @@ old_gdt:
__set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
#endif
- /* Clear %fs and %gs. */
- asm volatile ("movl %0, %%fs; movl %0, %%gs" : : "r" (0));
+ /* Clear %fs. */
+ asm volatile ("mov %0, %%fs" : : "r" (0));
/* Clear all 6 debug registers: */
set_debugreg(0, 0);
@@ -701,6 +779,37 @@ old_gdt:
mxcsr_feature_mask_init();
}
+/* Entrypoint to initialize secondary CPU */
+void __cpuinit secondary_cpu_init(void)
+{
+ int cpu = smp_processor_id();
+ struct task_struct *curr = current;
+
+ _cpu_init(cpu, curr);
+}
+
+/*
+ * cpu_init() initializes state that is per-CPU. Some data is already
+ * initialized (naturally) in the bootstrap process, such as the GDT
+ * and IDT. We reload them nevertheless, this function acts as a
+ * 'CPU state barrier', nothing should get across.
+ */
+void __cpuinit cpu_init(void)
+{
+ int cpu = smp_processor_id();
+ struct task_struct *curr = current;
+
+ /* Set up the real GDT and PDA, so we can transition from the
+ boot versions. */
+ if (!init_gdt(cpu, curr)) {
+ /* failed to allocate something; not much we can do... */
+ for (;;)
+ local_irq_enable();
+ }
+
+ _cpu_init(cpu, curr);
+}
+
#ifdef CONFIG_HOTPLUG_CPU
void __cpuinit cpu_uninit(void)
{