diff options
author | Fenghua Yu <fenghua.yu@intel.com> | 2012-11-13 19:32:41 (GMT) |
---|---|---|
committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-11-14 17:39:48 (GMT) |
commit | 30106c174311b8cfaaa3186c7f6f9c36c62d17da (patch) | |
tree | 58a0c368ebd8ccc48dddc9b723ed1296b9e741db | |
parent | 4d25031a81d3cd32edc00de6596db76cc4010685 (diff) | |
download | linux-fsl-qoriq-30106c174311b8cfaaa3186c7f6f9c36c62d17da.tar.xz |
x86, hotplug: Support functions for CPU0 online/offline
Add smp_store_boot_cpu_info() to store cpu info for BSP during boot time.
Now smp_store_cpu_info() stores cpu info for bringing up BSP or AP after
it's offline.
Continue to online CPU0 in native_cpu_up().
Continue to offline CPU0 in native_cpu_disable().
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1352835171-3958-5-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
-rw-r--r-- | arch/x86/include/asm/smp.h | 1 | ||||
-rw-r--r-- | arch/x86/kernel/smpboot.c | 38 |
2 files changed, 19 insertions, 20 deletions
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index 4f19a15..b073aae 100644 --- a/arch/x86/include/asm/smp.h +++ b/arch/x86/include/asm/smp.h @@ -166,6 +166,7 @@ void native_send_call_func_ipi(const struct cpumask *mask); void native_send_call_func_single_ipi(int cpu); void x86_idle_thread_init(unsigned int cpu, struct task_struct *idle); +void smp_store_boot_cpu_info(void); void smp_store_cpu_info(int id); #define cpu_physical_id(cpu) per_cpu(x86_cpu_to_apicid, cpu) diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index c80a33b..c297907 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -125,8 +125,8 @@ EXPORT_PER_CPU_SYMBOL(cpu_info); atomic_t init_deasserted; /* - * Report back to the Boot Processor. - * Running on AP. + * Report back to the Boot Processor during boot time or to the caller processor + * during CPU online. */ static void __cpuinit smp_callin(void) { @@ -279,19 +279,30 @@ notrace static void __cpuinit start_secondary(void *unused) cpu_idle(); } +void __init smp_store_boot_cpu_info(void) +{ + int id = 0; /* CPU 0 */ + struct cpuinfo_x86 *c = &cpu_data(id); + + *c = boot_cpu_data; + c->cpu_index = id; +} + /* * The bootstrap kernel entry code has set these up. Save them for * a given CPU */ - void __cpuinit smp_store_cpu_info(int id) { struct cpuinfo_x86 *c = &cpu_data(id); *c = boot_cpu_data; c->cpu_index = id; - if (id != 0) - identify_secondary_cpu(c); + /* + * During boot time, CPU0 has this setup already. Save the info when + * bringing up AP or offlined CPU0. + */ + identify_secondary_cpu(c); } static bool __cpuinit @@ -795,7 +806,7 @@ int __cpuinit native_cpu_up(unsigned int cpu, struct task_struct *tidle) pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu); - if (apicid == BAD_APICID || apicid == boot_cpu_physical_apicid || + if (apicid == BAD_APICID || !physid_isset(apicid, phys_cpu_present_map) || !apic->apic_id_valid(apicid)) { pr_err("%s: bad cpu %d\n", __func__, cpu); @@ -990,7 +1001,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) /* * Setup boot CPU information */ - smp_store_cpu_info(0); /* Final full version of the data */ + smp_store_boot_cpu_info(); /* Final full version of the data */ cpumask_copy(cpu_callin_mask, cpumask_of(0)); mb(); @@ -1214,19 +1225,6 @@ void cpu_disable_common(void) int native_cpu_disable(void) { - int cpu = smp_processor_id(); - - /* - * Perhaps use cpufreq to drop frequency, but that could go - * into generic code. - * - * We won't take down the boot processor on i386 due to some - * interrupts only being able to be serviced by the BSP. - * Especially so if we're not using an IOAPIC -zwane - */ - if (cpu == 0) - return -EBUSY; - clear_local_APIC(); cpu_disable_common(); |