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-rw-r--r--arch/arm/kernel/smp.c178
1 files changed, 162 insertions, 16 deletions
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 2c7217d971d..84f4cbf652e 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -19,14 +19,15 @@
#include <linux/mm.h>
#include <linux/err.h>
#include <linux/cpu.h>
-#include <linux/smp.h>
#include <linux/seq_file.h>
#include <linux/irq.h>
#include <linux/percpu.h>
#include <linux/clockchips.h>
#include <linux/completion.h>
+#include <linux/cpufreq.h>
#include <linux/atomic.h>
+#include <asm/smp.h>
#include <asm/cacheflush.h>
#include <asm/cpu.h>
#include <asm/cputype.h>
@@ -42,6 +43,8 @@
#include <asm/ptrace.h>
#include <asm/localtimer.h>
#include <asm/smp_plat.h>
+#include <asm/virt.h>
+#include <asm/mach/arch.h>
/*
* as from 2.5, kernels no longer have an init_tasks structure
@@ -50,8 +53,15 @@
*/
struct secondary_data secondary_data;
+/*
+ * control for which core is the next to come out of the secondary
+ * boot "holding pen"
+ */
+volatile int __cpuinitdata pen_release = -1;
+
enum ipi_msg_type {
- IPI_TIMER = 2,
+ IPI_WAKEUP,
+ IPI_TIMER,
IPI_RESCHEDULE,
IPI_CALL_FUNC,
IPI_CALL_FUNC_SINGLE,
@@ -60,6 +70,14 @@ enum ipi_msg_type {
static DECLARE_COMPLETION(cpu_running);
+static struct smp_operations smp_ops;
+
+void __init smp_set_ops(struct smp_operations *ops)
+{
+ if (ops)
+ smp_ops = *ops;
+};
+
int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle)
{
int ret;
@@ -100,13 +118,64 @@ int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle)
return ret;
}
+/* platform specific SMP operations */
+void __init smp_init_cpus(void)
+{
+ if (smp_ops.smp_init_cpus)
+ smp_ops.smp_init_cpus();
+}
+
+static void __init platform_smp_prepare_cpus(unsigned int max_cpus)
+{
+ if (smp_ops.smp_prepare_cpus)
+ smp_ops.smp_prepare_cpus(max_cpus);
+}
+
+static void __cpuinit platform_secondary_init(unsigned int cpu)
+{
+ if (smp_ops.smp_secondary_init)
+ smp_ops.smp_secondary_init(cpu);
+}
+
+int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ if (smp_ops.smp_boot_secondary)
+ return smp_ops.smp_boot_secondary(cpu, idle);
+ return -ENOSYS;
+}
+
#ifdef CONFIG_HOTPLUG_CPU
static void percpu_timer_stop(void);
+static int platform_cpu_kill(unsigned int cpu)
+{
+ if (smp_ops.cpu_kill)
+ return smp_ops.cpu_kill(cpu);
+ return 1;
+}
+
+static void platform_cpu_die(unsigned int cpu)
+{
+ if (smp_ops.cpu_die)
+ smp_ops.cpu_die(cpu);
+}
+
+static int platform_cpu_disable(unsigned int cpu)
+{
+ if (smp_ops.cpu_disable)
+ return smp_ops.cpu_disable(cpu);
+
+ /*
+ * By default, allow disabling all CPUs except the first one,
+ * since this is special on a lot of platforms, e.g. because
+ * of clock tick interrupts.
+ */
+ return cpu == 0 ? -EPERM : 0;
+}
/*
* __cpu_disable runs on the processor to be shutdown.
*/
-int __cpu_disable(void)
+int __cpuinit __cpu_disable(void)
{
unsigned int cpu = smp_processor_id();
int ret;
@@ -134,8 +203,11 @@ int __cpu_disable(void)
/*
* Flush user cache and TLB mappings, and then remove this CPU
* from the vm mask set of all processes.
+ *
+ * Caches are flushed to the Level of Unification Inner Shareable
+ * to write-back dirty lines to unified caches shared by all CPUs.
*/
- flush_cache_all();
+ flush_cache_louis();
local_flush_tlb_all();
clear_tasks_mm_cpumask(cpu);
@@ -149,7 +221,7 @@ static DECLARE_COMPLETION(cpu_died);
* called on the thread which is asking for a CPU to be shutdown -
* waits until shutdown has completed, or it is timed out.
*/
-void __cpu_die(unsigned int cpu)
+void __cpuinit __cpu_die(unsigned int cpu)
{
if (!wait_for_completion_timeout(&cpu_died, msecs_to_jiffies(5000))) {
pr_err("CPU%u: cpu didn't die\n", cpu);
@@ -179,7 +251,7 @@ void __ref cpu_die(void)
mb();
/* Tell __cpu_die() that this CPU is now safe to dispose of */
- complete(&cpu_died);
+ RCU_NONIDLE(complete(&cpu_died));
/*
* actual CPU shutdown procedure is at least platform (if not
@@ -209,6 +281,7 @@ static void __cpuinit smp_store_cpu_info(unsigned int cpuid)
struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid);
cpu_info->loops_per_jiffy = loops_per_jiffy;
+ cpu_info->cpuid = read_cpuid_id();
store_cpu_topology(cpuid);
}
@@ -222,22 +295,29 @@ static void percpu_timer_setup(void);
asmlinkage void __cpuinit secondary_start_kernel(void)
{
struct mm_struct *mm = &init_mm;
- unsigned int cpu = smp_processor_id();
+ unsigned int cpu;
+
+ /*
+ * The identity mapping is uncached (strongly ordered), so
+ * switch away from it before attempting any exclusive accesses.
+ */
+ cpu_switch_mm(mm->pgd, mm);
+ enter_lazy_tlb(mm, current);
+ local_flush_tlb_all();
/*
* All kernel threads share the same mm context; grab a
* reference and switch to it.
*/
+ cpu = smp_processor_id();
atomic_inc(&mm->mm_count);
current->active_mm = mm;
cpumask_set_cpu(cpu, mm_cpumask(mm));
- cpu_switch_mm(mm->pgd, mm);
- enter_lazy_tlb(mm, current);
- local_flush_tlb_all();
+
+ cpu_init();
printk("CPU%u: Booted secondary processor\n", cpu);
- cpu_init();
preempt_disable();
trace_hardirqs_off();
@@ -287,10 +367,13 @@ void __init smp_cpus_done(unsigned int max_cpus)
num_online_cpus(),
bogosum / (500000/HZ),
(bogosum / (5000/HZ)) % 100);
+
+ hyp_mode_check();
}
void __init smp_prepare_boot_cpu(void)
{
+ set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
}
void __init smp_prepare_cpus(unsigned int max_cpus)
@@ -341,13 +424,19 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
smp_cross_call(mask, IPI_CALL_FUNC);
}
+void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_WAKEUP);
+}
+
void arch_send_call_function_single_ipi(int cpu)
{
smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
}
static const char *ipi_types[NR_IPI] = {
-#define S(x,s) [x - IPI_TIMER] = s
+#define S(x,s) [x] = s
+ S(IPI_WAKEUP, "CPU wakeup interrupts"),
S(IPI_TIMER, "Timer broadcast interrupts"),
S(IPI_RESCHEDULE, "Rescheduling interrupts"),
S(IPI_CALL_FUNC, "Function call interrupts"),
@@ -362,7 +451,7 @@ void show_ipi_list(struct seq_file *p, int prec)
for (i = 0; i < NR_IPI; i++) {
seq_printf(p, "%*s%u: ", prec - 1, "IPI", i);
- for_each_present_cpu(cpu)
+ for_each_online_cpu(cpu)
seq_printf(p, "%10u ",
__get_irq_stat(cpu, ipi_irqs[i]));
@@ -500,10 +589,13 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
unsigned int cpu = smp_processor_id();
struct pt_regs *old_regs = set_irq_regs(regs);
- if (ipinr >= IPI_TIMER && ipinr < IPI_TIMER + NR_IPI)
- __inc_irq_stat(cpu, ipi_irqs[ipinr - IPI_TIMER]);
+ if (ipinr < NR_IPI)
+ __inc_irq_stat(cpu, ipi_irqs[ipinr]);
switch (ipinr) {
+ case IPI_WAKEUP:
+ break;
+
case IPI_TIMER:
irq_enter();
ipi_timer();
@@ -563,7 +655,8 @@ void smp_send_stop(void)
cpumask_copy(&mask, cpu_online_mask);
cpumask_clear_cpu(smp_processor_id(), &mask);
- smp_cross_call(&mask, IPI_CPU_STOP);
+ if (!cpumask_empty(&mask))
+ smp_cross_call(&mask, IPI_CPU_STOP);
/* Wait up to one second for other CPUs to stop */
timeout = USEC_PER_SEC;
@@ -583,3 +676,56 @@ int setup_profiling_timer(unsigned int multiplier)
{
return -EINVAL;
}
+
+#ifdef CONFIG_CPU_FREQ
+
+static DEFINE_PER_CPU(unsigned long, l_p_j_ref);
+static DEFINE_PER_CPU(unsigned long, l_p_j_ref_freq);
+static unsigned long global_l_p_j_ref;
+static unsigned long global_l_p_j_ref_freq;
+
+static int cpufreq_callback(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ struct cpufreq_freqs *freq = data;
+ int cpu = freq->cpu;
+
+ if (freq->flags & CPUFREQ_CONST_LOOPS)
+ return NOTIFY_OK;
+
+ if (!per_cpu(l_p_j_ref, cpu)) {
+ per_cpu(l_p_j_ref, cpu) =
+ per_cpu(cpu_data, cpu).loops_per_jiffy;
+ per_cpu(l_p_j_ref_freq, cpu) = freq->old;
+ if (!global_l_p_j_ref) {
+ global_l_p_j_ref = loops_per_jiffy;
+ global_l_p_j_ref_freq = freq->old;
+ }
+ }
+
+ if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) ||
+ (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) ||
+ (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) {
+ loops_per_jiffy = cpufreq_scale(global_l_p_j_ref,
+ global_l_p_j_ref_freq,
+ freq->new);
+ per_cpu(cpu_data, cpu).loops_per_jiffy =
+ cpufreq_scale(per_cpu(l_p_j_ref, cpu),
+ per_cpu(l_p_j_ref_freq, cpu),
+ freq->new);
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block cpufreq_notifier = {
+ .notifier_call = cpufreq_callback,
+};
+
+static int __init register_cpufreq_notifier(void)
+{
+ return cpufreq_register_notifier(&cpufreq_notifier,
+ CPUFREQ_TRANSITION_NOTIFIER);
+}
+core_initcall(register_cpufreq_notifier);
+
+#endif