diff options
| -rw-r--r-- | arch/x86/kernel/head64.c | 11 | ||||
| -rw-r--r-- | arch/x86/xen/enlighten.c | 5 | ||||
| -rw-r--r-- | include/asm-x86/percpu.h | 26 | ||||
| -rw-r--r-- | include/asm-x86/setup.h | 1 |
4 files changed, 40 insertions, 3 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index c9781982914..1b318e903bf 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -39,6 +39,13 @@ static struct x8664_pda *__cpu_pda[NR_CPUS] __initdata; static struct x8664_pda *__cpu_pda[NR_CPUS] __read_mostly; #endif +void __init x86_64_init_pda(void) +{ + _cpu_pda = __cpu_pda; + cpu_pda(0) = &_boot_cpu_pda; + pda_init(0); +} + static void __init zap_identity_mappings(void) { pgd_t *pgd = pgd_offset_k(0UL); @@ -102,9 +109,7 @@ void __init x86_64_start_kernel(char * real_mode_data) early_printk("Kernel alive\n"); - _cpu_pda = __cpu_pda; - cpu_pda(0) = &_boot_cpu_pda; - pda_init(0); + x86_64_init_pda(); early_printk("Kernel really alive\n"); diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index a85f447b8d0..f3f11acf785 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -971,6 +971,7 @@ void xen_setup_vcpu_info_placement(void) /* xen_vcpu_setup managed to place the vcpu_info within the percpu area for all cpus, so make use of it */ +#ifdef CONFIG_X86_32 if (have_vcpu_info_placement) { printk(KERN_INFO "Xen: using vcpu_info placement\n"); @@ -980,6 +981,7 @@ void xen_setup_vcpu_info_placement(void) pv_irq_ops.irq_enable = xen_irq_enable_direct; pv_mmu_ops.read_cr2 = xen_read_cr2_direct; } +#endif } static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf, @@ -1000,10 +1002,12 @@ static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf, goto patch_site switch (type) { +#ifdef CONFIG_X86_32 SITE(pv_irq_ops, irq_enable); SITE(pv_irq_ops, irq_disable); SITE(pv_irq_ops, save_fl); SITE(pv_irq_ops, restore_fl); +#endif /* CONFIG_X86_32 */ #undef SITE patch_site: @@ -1323,6 +1327,7 @@ asmlinkage void __init xen_start_kernel(void) #ifdef CONFIG_X86_64 /* Disable until direct per-cpu data access. */ have_vcpu_info_placement = 0; + x86_64_init_pda(); #endif xen_smp_init(); diff --git a/include/asm-x86/percpu.h b/include/asm-x86/percpu.h index 912a3a17b9d..4e91ee1e37a 100644 --- a/include/asm-x86/percpu.h +++ b/include/asm-x86/percpu.h @@ -22,6 +22,32 @@ DECLARE_PER_CPU(struct x8664_pda, pda); +/* + * These are supposed to be implemented as a single instruction which + * operates on the per-cpu data base segment. x86-64 doesn't have + * that yet, so this is a fairly inefficient workaround for the + * meantime. The single instruction is atomic with respect to + * preemption and interrupts, so we need to explicitly disable + * interrupts here to achieve the same effect. However, because it + * can be used from within interrupt-disable/enable, we can't actually + * disable interrupts; disabling preemption is enough. + */ +#define x86_read_percpu(var) \ + ({ \ + typeof(per_cpu_var(var)) __tmp; \ + preempt_disable(); \ + __tmp = __get_cpu_var(var); \ + preempt_enable(); \ + __tmp; \ + }) + +#define x86_write_percpu(var, val) \ + do { \ + preempt_disable(); \ + __get_cpu_var(var) = (val); \ + preempt_enable(); \ + } while(0) + #else /* CONFIG_X86_64 */ #ifdef __ASSEMBLY__ diff --git a/include/asm-x86/setup.h b/include/asm-x86/setup.h index 90ab2225e71..659492624e7 100644 --- a/include/asm-x86/setup.h +++ b/include/asm-x86/setup.h @@ -76,6 +76,7 @@ extern unsigned long init_pg_tables_start; extern unsigned long init_pg_tables_end; #else +void __init x86_64_init_pda(void); void __init x86_64_start_kernel(char *real_mode); void __init x86_64_start_reservations(char *real_mode_data); |