arch/x86/xen/smp.c

   1 #include <linux/smp.h>
   2 #include <linux/slab.h>
   3 #include <linux/cpumask.h>
   4 #include <linux/percpu.h>
   5
   6 #include <xen/events.h>
   7
   8 #include <xen/hvc-console.h>
   9 #include "xen-ops.h"
  10 #include "smp.h"
  11
  12 static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 };
  13 static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
  14 static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
  15 static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };
  16
  17 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
  18 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
  19
  20 /*
  21  * Reschedule call back.
  22  */
  23 static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
  24 {
  25         inc_irq_stat(irq_resched_count);
  26         scheduler_ipi();
  27
  28         return IRQ_HANDLED;
  29 }
  30
  31 void xen_smp_intr_free(unsigned int cpu)
  32 {
  33         if (per_cpu(xen_resched_irq, cpu).irq >= 0) {
  34                 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL);
  35                 per_cpu(xen_resched_irq, cpu).irq = -1;
  36                 kfree(per_cpu(xen_resched_irq, cpu).name);
  37                 per_cpu(xen_resched_irq, cpu).name = NULL;
  38         }
  39         if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) {
  40                 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL);
  41                 per_cpu(xen_callfunc_irq, cpu).irq = -1;
  42                 kfree(per_cpu(xen_callfunc_irq, cpu).name);
  43                 per_cpu(xen_callfunc_irq, cpu).name = NULL;
  44         }
  45         if (per_cpu(xen_debug_irq, cpu).irq >= 0) {
  46                 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL);
  47                 per_cpu(xen_debug_irq, cpu).irq = -1;
  48                 kfree(per_cpu(xen_debug_irq, cpu).name);
  49                 per_cpu(xen_debug_irq, cpu).name = NULL;
  50         }
  51         if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) {
  52                 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq,
  53                                        NULL);
  54                 per_cpu(xen_callfuncsingle_irq, cpu).irq = -1;
  55                 kfree(per_cpu(xen_callfuncsingle_irq, cpu).name);
  56                 per_cpu(xen_callfuncsingle_irq, cpu).name = NULL;
  57         }
  58 }
  59
  60 int xen_smp_intr_init(unsigned int cpu)
  61 {
  62         int rc;
  63         char *resched_name, *callfunc_name, *debug_name;
  64
  65         resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
  66         rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
  67                                     cpu,
  68                                     xen_reschedule_interrupt,
  69                                     IRQF_PERCPU|IRQF_NOBALANCING,
  70                                     resched_name,
  71                                     NULL);
  72         if (rc < 0)
  73                 goto fail;
  74         per_cpu(xen_resched_irq, cpu).irq = rc;
  75         per_cpu(xen_resched_irq, cpu).name = resched_name;
  76
  77         callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
  78         rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
  79                                     cpu,
  80                                     xen_call_function_interrupt,
  81                                     IRQF_PERCPU|IRQF_NOBALANCING,
  82                                     callfunc_name,
  83                                     NULL);
  84         if (rc < 0)
  85                 goto fail;
  86         per_cpu(xen_callfunc_irq, cpu).irq = rc;
  87         per_cpu(xen_callfunc_irq, cpu).name = callfunc_name;
  88
  89         debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
  90         rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
  91                                      IRQF_PERCPU | IRQF_NOBALANCING,
  92                                      debug_name, NULL);
  93         if (rc < 0)
  94                 goto fail;
  95         per_cpu(xen_debug_irq, cpu).irq = rc;
  96         per_cpu(xen_debug_irq, cpu).name = debug_name;
  97
  98         callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
  99         rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
 100                                     cpu,
 101                                     xen_call_function_single_interrupt,
 102                                     IRQF_PERCPU|IRQF_NOBALANCING,
 103                                     callfunc_name,
 104                                     NULL);
 105         if (rc < 0)
 106                 goto fail;
 107         per_cpu(xen_callfuncsingle_irq, cpu).irq = rc;
 108         per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name;
 109
 110         return 0;
 111
 112  fail:
 113         xen_smp_intr_free(cpu);
 114         return rc;
 115 }
 116
 117 void xen_smp_send_reschedule(int cpu)
 118 {
 119         xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
 120 }
 121
 122 static void __xen_send_IPI_mask(const struct cpumask *mask,
 123                               int vector)
 124 {
 125         unsigned cpu;
 126
 127         for_each_cpu_and(cpu, mask, cpu_online_mask)
 128                 xen_send_IPI_one(cpu, vector);
 129 }
 130
 131 void xen_smp_send_call_function_ipi(const struct cpumask *mask)
 132 {
 133         int cpu;
 134
 135         __xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
 136
 137         /* Make sure other vcpus get a chance to run if they need to. */
 138         for_each_cpu(cpu, mask) {
 139                 if (xen_vcpu_stolen(cpu)) {
 140                         HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
 141                         break;
 142                 }
 143         }
 144 }
 145
 146 void xen_smp_send_call_function_single_ipi(int cpu)
 147 {
 148         __xen_send_IPI_mask(cpumask_of(cpu),
 149                           XEN_CALL_FUNCTION_SINGLE_VECTOR);
 150 }
 151
 152 static inline int xen_map_vector(int vector)
 153 {
 154         int xen_vector;
 155
 156         switch (vector) {
 157         case RESCHEDULE_VECTOR:
 158                 xen_vector = XEN_RESCHEDULE_VECTOR;
 159                 break;
 160         case CALL_FUNCTION_VECTOR:
 161                 xen_vector = XEN_CALL_FUNCTION_VECTOR;
 162                 break;
 163         case CALL_FUNCTION_SINGLE_VECTOR:
 164                 xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
 165                 break;
 166         case IRQ_WORK_VECTOR:
 167                 xen_vector = XEN_IRQ_WORK_VECTOR;
 168                 break;
 169 #ifdef CONFIG_X86_64
 170         case NMI_VECTOR:
 171         case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
 172                 xen_vector = XEN_NMI_VECTOR;
 173                 break;
 174 #endif
 175         default:
 176                 xen_vector = -1;
 177                 printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
 178                         vector);
 179         }
 180
 181         return xen_vector;
 182 }
 183
 184 void xen_send_IPI_mask(const struct cpumask *mask,
 185                               int vector)
 186 {
 187         int xen_vector = xen_map_vector(vector);
 188
 189         if (xen_vector >= 0)
 190                 __xen_send_IPI_mask(mask, xen_vector);
 191 }
 192
 193 void xen_send_IPI_all(int vector)
 194 {
 195         int xen_vector = xen_map_vector(vector);
 196
 197         if (xen_vector >= 0)
 198                 __xen_send_IPI_mask(cpu_online_mask, xen_vector);
 199 }
 200
 201 void xen_send_IPI_self(int vector)
 202 {
 203         int xen_vector = xen_map_vector(vector);
 204
 205         if (xen_vector >= 0)
 206                 xen_send_IPI_one(smp_processor_id(), xen_vector);
 207 }
 208
 209 void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
 210                                 int vector)
 211 {
 212         unsigned cpu;
 213         unsigned int this_cpu = smp_processor_id();
 214         int xen_vector = xen_map_vector(vector);
 215
 216         if (!(num_online_cpus() > 1) || (xen_vector < 0))
 217                 return;
 218
 219         for_each_cpu_and(cpu, mask, cpu_online_mask) {
 220                 if (this_cpu == cpu)
 221                         continue;
 222
 223                 xen_send_IPI_one(cpu, xen_vector);
 224         }
 225 }
 226
 227 void xen_send_IPI_allbutself(int vector)
 228 {
 229         xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
 230 }
 231
 232 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
 233 {
 234         irq_enter();
 235         generic_smp_call_function_interrupt();
 236         inc_irq_stat(irq_call_count);
 237         irq_exit();
 238
 239         return IRQ_HANDLED;
 240 }
 241
 242 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
 243 {
 244         irq_enter();
 245         generic_smp_call_function_single_interrupt();
 246         inc_irq_stat(irq_call_count);
 247         irq_exit();
 248
 249         return IRQ_HANDLED;
 250 }