diff options
| -rw-r--r-- | arch/i386/kernel/smp.c | 27 | ||||
| -rw-r--r-- | include/asm-i386/smp.h | 2 |
2 files changed, 29 insertions, 0 deletions
diff --git a/arch/i386/kernel/smp.c b/arch/i386/kernel/smp.c index 465188e2d701..1b080ab8a49f 100644 --- a/arch/i386/kernel/smp.c +++ b/arch/i386/kernel/smp.c @@ -700,3 +700,30 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, return 0; } EXPORT_SYMBOL(smp_call_function_single); + +static int convert_apicid_to_cpu(int apic_id) +{ + int i; + + for (i = 0; i < NR_CPUS; i++) { + if (x86_cpu_to_apicid[i] == apic_id) + return i; + } + return -1; +} + +int safe_smp_processor_id(void) +{ + int apicid, cpuid; + + if (!boot_cpu_has(X86_FEATURE_APIC)) + return 0; + + apicid = hard_smp_processor_id(); + if (apicid == BAD_APICID) + return 0; + + cpuid = convert_apicid_to_cpu(apicid); + + return cpuid >= 0 ? cpuid : 0; +} diff --git a/include/asm-i386/smp.h b/include/asm-i386/smp.h index 915c26a31b79..6aa1206f6e2a 100644 --- a/include/asm-i386/smp.h +++ b/include/asm-i386/smp.h @@ -84,6 +84,7 @@ static inline int hard_smp_processor_id(void) #endif #endif +extern int safe_smp_processor_id(void); extern int __cpu_disable(void); extern void __cpu_die(unsigned int cpu); extern unsigned int num_processors; @@ -92,6 +93,7 @@ extern unsigned int num_processors; #else /* CONFIG_SMP */ +#define safe_smp_processor_id() 0 #define cpu_physical_id(cpu) boot_cpu_physical_apicid #define NO_PROC_ID 0xFF /* No processor magic marker */ |