linux/arch/x86/kernel/apic/x2apic_cluster.c
<<
>>
Prefs
   1#include <linux/threads.h>
   2#include <linux/cpumask.h>
   3#include <linux/string.h>
   4#include <linux/kernel.h>
   5#include <linux/ctype.h>
   6#include <linux/dmar.h>
   7#include <linux/cpu.h>
   8
   9#include <asm/smp.h>
  10#include <asm/x2apic.h>
  11
  12static DEFINE_PER_CPU(u32, x86_cpu_to_logical_apicid);
  13static DEFINE_PER_CPU(cpumask_var_t, cpus_in_cluster);
  14static DEFINE_PER_CPU(cpumask_var_t, ipi_mask);
  15
  16static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
  17{
  18        return x2apic_enabled();
  19}
  20
  21static inline u32 x2apic_cluster(int cpu)
  22{
  23        return per_cpu(x86_cpu_to_logical_apicid, cpu) >> 16;
  24}
  25
  26static void
  27__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
  28{
  29        struct cpumask *cpus_in_cluster_ptr;
  30        struct cpumask *ipi_mask_ptr;
  31        unsigned int cpu, this_cpu;
  32        unsigned long flags;
  33        u32 dest;
  34
  35        x2apic_wrmsr_fence();
  36
  37        local_irq_save(flags);
  38
  39        this_cpu = smp_processor_id();
  40
  41        /*
  42         * We are to modify mask, so we need an own copy
  43         * and be sure it's manipulated with irq off.
  44         */
  45        ipi_mask_ptr = __raw_get_cpu_var(ipi_mask);
  46        cpumask_copy(ipi_mask_ptr, mask);
  47
  48        /*
  49         * The idea is to send one IPI per cluster.
  50         */
  51        for_each_cpu(cpu, ipi_mask_ptr) {
  52                unsigned long i;
  53
  54                cpus_in_cluster_ptr = per_cpu(cpus_in_cluster, cpu);
  55                dest = 0;
  56
  57                /* Collect cpus in cluster. */
  58                for_each_cpu_and(i, ipi_mask_ptr, cpus_in_cluster_ptr) {
  59                        if (apic_dest == APIC_DEST_ALLINC || i != this_cpu)
  60                                dest |= per_cpu(x86_cpu_to_logical_apicid, i);
  61                }
  62
  63                if (!dest)
  64                        continue;
  65
  66                __x2apic_send_IPI_dest(dest, vector, apic->dest_logical);
  67                /*
  68                 * Cluster sibling cpus should be discared now so
  69                 * we would not send IPI them second time.
  70                 */
  71                cpumask_andnot(ipi_mask_ptr, ipi_mask_ptr, cpus_in_cluster_ptr);
  72        }
  73
  74        local_irq_restore(flags);
  75}
  76
  77static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
  78{
  79        __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
  80}
  81
  82static void
  83x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
  84{
  85        __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
  86}
  87
  88static void x2apic_send_IPI_allbutself(int vector)
  89{
  90        __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLBUT);
  91}
  92
  93static void x2apic_send_IPI_all(int vector)
  94{
  95        __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
  96}
  97
  98static int
  99x2apic_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
 100                              const struct cpumask *andmask,
 101                              unsigned int *apicid)
 102{
 103        u32 dest = 0;
 104        u16 cluster;
 105        int i;
 106
 107        for_each_cpu_and(i, cpumask, andmask) {
 108                if (!cpumask_test_cpu(i, cpu_online_mask))
 109                        continue;
 110                dest = per_cpu(x86_cpu_to_logical_apicid, i);
 111                cluster = x2apic_cluster(i);
 112                break;
 113        }
 114
 115        if (!dest)
 116                return -EINVAL;
 117
 118        for_each_cpu_and(i, cpumask, andmask) {
 119                if (!cpumask_test_cpu(i, cpu_online_mask))
 120                        continue;
 121                if (cluster != x2apic_cluster(i))
 122                        continue;
 123                dest |= per_cpu(x86_cpu_to_logical_apicid, i);
 124        }
 125
 126        *apicid = dest;
 127
 128        return 0;
 129}
 130
 131static void init_x2apic_ldr(void)
 132{
 133        unsigned int this_cpu = smp_processor_id();
 134        unsigned int cpu;
 135
 136        per_cpu(x86_cpu_to_logical_apicid, this_cpu) = apic_read(APIC_LDR);
 137
 138        __cpu_set(this_cpu, per_cpu(cpus_in_cluster, this_cpu));
 139        for_each_online_cpu(cpu) {
 140                if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu))
 141                        continue;
 142                __cpu_set(this_cpu, per_cpu(cpus_in_cluster, cpu));
 143                __cpu_set(cpu, per_cpu(cpus_in_cluster, this_cpu));
 144        }
 145}
 146
 147 /*
 148  * At CPU state changes, update the x2apic cluster sibling info.
 149  */
 150static int
 151update_clusterinfo(struct notifier_block *nfb, unsigned long action, void *hcpu)
 152{
 153        unsigned int this_cpu = (unsigned long)hcpu;
 154        unsigned int cpu;
 155        int err = 0;
 156
 157        switch (action) {
 158        case CPU_UP_PREPARE:
 159                if (!zalloc_cpumask_var(&per_cpu(cpus_in_cluster, this_cpu),
 160                                        GFP_KERNEL)) {
 161                        err = -ENOMEM;
 162                } else if (!zalloc_cpumask_var(&per_cpu(ipi_mask, this_cpu),
 163                                               GFP_KERNEL)) {
 164                        free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu));
 165                        err = -ENOMEM;
 166                }
 167                break;
 168        case CPU_UP_CANCELED:
 169        case CPU_UP_CANCELED_FROZEN:
 170        case CPU_DEAD:
 171                for_each_online_cpu(cpu) {
 172                        if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu))
 173                                continue;
 174                        __cpu_clear(this_cpu, per_cpu(cpus_in_cluster, cpu));
 175                        __cpu_clear(cpu, per_cpu(cpus_in_cluster, this_cpu));
 176                }
 177                free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu));
 178                free_cpumask_var(per_cpu(ipi_mask, this_cpu));
 179                break;
 180        }
 181
 182        return notifier_from_errno(err);
 183}
 184
 185static struct notifier_block __refdata x2apic_cpu_notifier = {
 186        .notifier_call = update_clusterinfo,
 187};
 188
 189static int x2apic_init_cpu_notifier(void)
 190{
 191        int cpu = smp_processor_id();
 192
 193        zalloc_cpumask_var(&per_cpu(cpus_in_cluster, cpu), GFP_KERNEL);
 194        zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL);
 195
 196        BUG_ON(!per_cpu(cpus_in_cluster, cpu) || !per_cpu(ipi_mask, cpu));
 197
 198        __cpu_set(cpu, per_cpu(cpus_in_cluster, cpu));
 199        register_hotcpu_notifier(&x2apic_cpu_notifier);
 200        return 1;
 201}
 202
 203static int x2apic_cluster_probe(void)
 204{
 205        if (x2apic_mode)
 206                return x2apic_init_cpu_notifier();
 207        else
 208                return 0;
 209}
 210
 211static const struct cpumask *x2apic_cluster_target_cpus(void)
 212{
 213        return cpu_all_mask;
 214}
 215
 216/*
 217 * Each x2apic cluster is an allocation domain.
 218 */
 219static void cluster_vector_allocation_domain(int cpu, struct cpumask *retmask,
 220                                             const struct cpumask *mask)
 221{
 222        /*
 223         * To minimize vector pressure, default case of boot, device bringup
 224         * etc will use a single cpu for the interrupt destination.
 225         *
 226         * On explicit migration requests coming from irqbalance etc,
 227         * interrupts will be routed to the x2apic cluster (cluster-id
 228         * derived from the first cpu in the mask) members specified
 229         * in the mask.
 230         */
 231        if (mask == x2apic_cluster_target_cpus())
 232                cpumask_copy(retmask, cpumask_of(cpu));
 233        else
 234                cpumask_and(retmask, mask, per_cpu(cpus_in_cluster, cpu));
 235}
 236
 237static struct apic apic_x2apic_cluster = {
 238
 239        .name                           = "cluster x2apic",
 240        .probe                          = x2apic_cluster_probe,
 241        .acpi_madt_oem_check            = x2apic_acpi_madt_oem_check,
 242        .apic_id_valid                  = x2apic_apic_id_valid,
 243        .apic_id_registered             = x2apic_apic_id_registered,
 244
 245        .irq_delivery_mode              = dest_LowestPrio,
 246        .irq_dest_mode                  = 1, /* logical */
 247
 248        .target_cpus                    = x2apic_cluster_target_cpus,
 249        .disable_esr                    = 0,
 250        .dest_logical                   = APIC_DEST_LOGICAL,
 251        .check_apicid_used              = NULL,
 252        .check_apicid_present           = NULL,
 253
 254        .vector_allocation_domain       = cluster_vector_allocation_domain,
 255        .init_apic_ldr                  = init_x2apic_ldr,
 256
 257        .ioapic_phys_id_map             = NULL,
 258        .setup_apic_routing             = NULL,
 259        .multi_timer_check              = NULL,
 260        .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 261        .apicid_to_cpu_present          = NULL,
 262        .setup_portio_remap             = NULL,
 263        .check_phys_apicid_present      = default_check_phys_apicid_present,
 264        .enable_apic_mode               = NULL,
 265        .phys_pkg_id                    = x2apic_phys_pkg_id,
 266        .mps_oem_check                  = NULL,
 267
 268        .get_apic_id                    = x2apic_get_apic_id,
 269        .set_apic_id                    = x2apic_set_apic_id,
 270        .apic_id_mask                   = 0xFFFFFFFFu,
 271
 272        .cpu_mask_to_apicid_and         = x2apic_cpu_mask_to_apicid_and,
 273
 274        .send_IPI_mask                  = x2apic_send_IPI_mask,
 275        .send_IPI_mask_allbutself       = x2apic_send_IPI_mask_allbutself,
 276        .send_IPI_allbutself            = x2apic_send_IPI_allbutself,
 277        .send_IPI_all                   = x2apic_send_IPI_all,
 278        .send_IPI_self                  = x2apic_send_IPI_self,
 279
 280        .trampoline_phys_low            = DEFAULT_TRAMPOLINE_PHYS_LOW,
 281        .trampoline_phys_high           = DEFAULT_TRAMPOLINE_PHYS_HIGH,
 282        .wait_for_init_deassert         = NULL,
 283        .smp_callin_clear_local_apic    = NULL,
 284        .inquire_remote_apic            = NULL,
 285
 286        .read                           = native_apic_msr_read,
 287        .write                          = native_apic_msr_write,
 288        .eoi_write                      = native_apic_msr_eoi_write,
 289        .icr_read                       = native_x2apic_icr_read,
 290        .icr_write                      = native_x2apic_icr_write,
 291        .wait_icr_idle                  = native_x2apic_wait_icr_idle,
 292        .safe_wait_icr_idle             = native_safe_x2apic_wait_icr_idle,
 293};
 294
 295apic_driver(apic_x2apic_cluster);
 296