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x86: load new GDT after setting up boot cpu per-cpu area 

Impact: sync 32 and 64-bit code

Merge load_gs_base() into switch_to_new_gdt().  Load the GDT and
per-cpu state for the boot cpu when its new area is set up.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
hifive-unleashed-5.1
Brian Gerst 2009-01-27 12:56:48 +09:00 committed by Tejun Heo
parent 1825b8edc2
commit 2697fbd5fa
3 changed files with 12 additions and 14 deletions
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5
arch/x86/include/asm/processor.h
View File

@ -394,11 +394,6 @@ union irq_stack_union {
DECLARE_PER_CPU(union irq_stack_union, irq_stack_union);
DECLARE_PER_CPU(char *, irq_stack_ptr);
static inline void load_gs_base(int cpu)
{
wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
}
#endif
extern void print_cpu_info(struct cpuinfo_x86 *);

15
arch/x86/kernel/cpu/common.c
View File

@ -258,12 +258,17 @@ __u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata;
void switch_to_new_gdt(void)
{
struct desc_ptr gdt_descr;
int cpu = smp_processor_id();
gdt_descr.address = (long)get_cpu_gdt_table(smp_processor_id());
gdt_descr.address = (long)get_cpu_gdt_table(cpu);
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
/* Reload the per-cpu base */
#ifdef CONFIG_X86_32
asm("mov %0, %%fs" : : "r" (__KERNEL_PERCPU) : "memory");
loadsegment(fs, __KERNEL_PERCPU);
#else
loadsegment(gs, 0);
wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
#endif
}
@ -968,10 +973,6 @@ void __cpuinit cpu_init(void)
struct task_struct *me;
int i;
loadsegment(fs, 0);
loadsegment(gs, 0);
load_gs_base(cpu);
#ifdef CONFIG_NUMA
if (cpu != 0 && percpu_read(node_number) == 0 &&
cpu_to_node(cpu) != NUMA_NO_NODE)
@ -993,6 +994,8 @@ void __cpuinit cpu_init(void)
*/
switch_to_new_gdt();
loadsegment(fs, 0);
load_idt((const struct desc_ptr *)&idt_descr);
memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);

6
arch/x86/kernel/setup_percpu.c
View File

@ -112,14 +112,14 @@ void __init setup_per_cpu_areas(void)
#ifdef CONFIG_NUMA
per_cpu(x86_cpu_to_node_map, cpu) =
early_per_cpu_map(x86_cpu_to_node_map, cpu);
#endif
#endif
/*
* Up to this point, the boot CPU has been using .data.init
* area. Reload %gs offset for the boot CPU.
* area. Reload any changed state for the boot CPU.
*/
if (cpu == boot_cpu_id)
load_gs_base(cpu);
#endif
switch_to_new_gdt();
DBG("PERCPU: cpu %4d %p\n", cpu, ptr);
}