x2apic_cluster.c 6.9 KB

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  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/irq.h>
  8. #include <linux/cpu.h>
  9. #include <asm/smp.h>
  10. #include <asm/x2apic.h>
  11. static DEFINE_PER_CPU(u32, x86_cpu_to_logical_apicid);
  12. static DEFINE_PER_CPU(cpumask_var_t, cpus_in_cluster);
  13. static DEFINE_PER_CPU(cpumask_var_t, ipi_mask);
  14. static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
  15. {
  16. return x2apic_enabled();
  17. }
  18. static inline u32 x2apic_cluster(int cpu)
  19. {
  20. return per_cpu(x86_cpu_to_logical_apicid, cpu) >> 16;
  21. }
  22. static void x2apic_send_IPI(int cpu, int vector)
  23. {
  24. u32 dest = per_cpu(x86_cpu_to_logical_apicid, cpu);
  25. x2apic_wrmsr_fence();
  26. __x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
  27. }
  28. static void
  29. __x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
  30. {
  31. struct cpumask *cpus_in_cluster_ptr;
  32. struct cpumask *ipi_mask_ptr;
  33. unsigned int cpu, this_cpu;
  34. unsigned long flags;
  35. u32 dest;
  36. x2apic_wrmsr_fence();
  37. local_irq_save(flags);
  38. this_cpu = smp_processor_id();
  39. /*
  40. * We are to modify mask, so we need an own copy
  41. * and be sure it's manipulated with irq off.
  42. */
  43. ipi_mask_ptr = this_cpu_cpumask_var_ptr(ipi_mask);
  44. cpumask_copy(ipi_mask_ptr, mask);
  45. /*
  46. * The idea is to send one IPI per cluster.
  47. */
  48. for_each_cpu(cpu, ipi_mask_ptr) {
  49. unsigned long i;
  50. cpus_in_cluster_ptr = per_cpu(cpus_in_cluster, cpu);
  51. dest = 0;
  52. /* Collect cpus in cluster. */
  53. for_each_cpu_and(i, ipi_mask_ptr, cpus_in_cluster_ptr) {
  54. if (apic_dest == APIC_DEST_ALLINC || i != this_cpu)
  55. dest |= per_cpu(x86_cpu_to_logical_apicid, i);
  56. }
  57. if (!dest)
  58. continue;
  59. __x2apic_send_IPI_dest(dest, vector, apic->dest_logical);
  60. /*
  61. * Cluster sibling cpus should be discared now so
  62. * we would not send IPI them second time.
  63. */
  64. cpumask_andnot(ipi_mask_ptr, ipi_mask_ptr, cpus_in_cluster_ptr);
  65. }
  66. local_irq_restore(flags);
  67. }
  68. static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
  69. {
  70. __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
  71. }
  72. static void
  73. x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
  74. {
  75. __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
  76. }
  77. static void x2apic_send_IPI_allbutself(int vector)
  78. {
  79. __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLBUT);
  80. }
  81. static void x2apic_send_IPI_all(int vector)
  82. {
  83. __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
  84. }
  85. static int
  86. x2apic_cpu_mask_to_apicid(const struct cpumask *mask, struct irq_data *irqdata,
  87. unsigned int *apicid)
  88. {
  89. struct cpumask *effmsk = irq_data_get_effective_affinity_mask(irqdata);
  90. unsigned int cpu;
  91. u32 dest = 0;
  92. u16 cluster;
  93. cpu = cpumask_first(mask);
  94. if (cpu >= nr_cpu_ids)
  95. return -EINVAL;
  96. dest = per_cpu(x86_cpu_to_logical_apicid, cpu);
  97. cluster = x2apic_cluster(cpu);
  98. cpumask_clear(effmsk);
  99. for_each_cpu(cpu, mask) {
  100. if (cluster != x2apic_cluster(cpu))
  101. continue;
  102. dest |= per_cpu(x86_cpu_to_logical_apicid, cpu);
  103. cpumask_set_cpu(cpu, effmsk);
  104. }
  105. *apicid = dest;
  106. return 0;
  107. }
  108. static void init_x2apic_ldr(void)
  109. {
  110. unsigned int this_cpu = smp_processor_id();
  111. unsigned int cpu;
  112. per_cpu(x86_cpu_to_logical_apicid, this_cpu) = apic_read(APIC_LDR);
  113. cpumask_set_cpu(this_cpu, per_cpu(cpus_in_cluster, this_cpu));
  114. for_each_online_cpu(cpu) {
  115. if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu))
  116. continue;
  117. cpumask_set_cpu(this_cpu, per_cpu(cpus_in_cluster, cpu));
  118. cpumask_set_cpu(cpu, per_cpu(cpus_in_cluster, this_cpu));
  119. }
  120. }
  121. /*
  122. * At CPU state changes, update the x2apic cluster sibling info.
  123. */
  124. static int x2apic_prepare_cpu(unsigned int cpu)
  125. {
  126. if (!zalloc_cpumask_var(&per_cpu(cpus_in_cluster, cpu), GFP_KERNEL))
  127. return -ENOMEM;
  128. if (!zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL)) {
  129. free_cpumask_var(per_cpu(cpus_in_cluster, cpu));
  130. return -ENOMEM;
  131. }
  132. return 0;
  133. }
  134. static int x2apic_dead_cpu(unsigned int this_cpu)
  135. {
  136. int cpu;
  137. for_each_online_cpu(cpu) {
  138. if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu))
  139. continue;
  140. cpumask_clear_cpu(this_cpu, per_cpu(cpus_in_cluster, cpu));
  141. cpumask_clear_cpu(cpu, per_cpu(cpus_in_cluster, this_cpu));
  142. }
  143. free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu));
  144. free_cpumask_var(per_cpu(ipi_mask, this_cpu));
  145. return 0;
  146. }
  147. static int x2apic_cluster_probe(void)
  148. {
  149. int cpu = smp_processor_id();
  150. int ret;
  151. if (!x2apic_mode)
  152. return 0;
  153. ret = cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "x86/x2apic:prepare",
  154. x2apic_prepare_cpu, x2apic_dead_cpu);
  155. if (ret < 0) {
  156. pr_err("Failed to register X2APIC_PREPARE\n");
  157. return 0;
  158. }
  159. cpumask_set_cpu(cpu, per_cpu(cpus_in_cluster, cpu));
  160. return 1;
  161. }
  162. static const struct cpumask *x2apic_cluster_target_cpus(void)
  163. {
  164. return cpu_all_mask;
  165. }
  166. /*
  167. * Each x2apic cluster is an allocation domain.
  168. */
  169. static void cluster_vector_allocation_domain(int cpu, struct cpumask *retmask,
  170. const struct cpumask *mask)
  171. {
  172. /*
  173. * To minimize vector pressure, default case of boot, device bringup
  174. * etc will use a single cpu for the interrupt destination.
  175. *
  176. * On explicit migration requests coming from irqbalance etc,
  177. * interrupts will be routed to the x2apic cluster (cluster-id
  178. * derived from the first cpu in the mask) members specified
  179. * in the mask.
  180. */
  181. if (mask == x2apic_cluster_target_cpus())
  182. cpumask_copy(retmask, cpumask_of(cpu));
  183. else
  184. cpumask_and(retmask, mask, per_cpu(cpus_in_cluster, cpu));
  185. }
  186. static struct apic apic_x2apic_cluster __ro_after_init = {
  187. .name = "cluster x2apic",
  188. .probe = x2apic_cluster_probe,
  189. .acpi_madt_oem_check = x2apic_acpi_madt_oem_check,
  190. .apic_id_valid = x2apic_apic_id_valid,
  191. .apic_id_registered = x2apic_apic_id_registered,
  192. .irq_delivery_mode = dest_LowestPrio,
  193. .irq_dest_mode = 1, /* logical */
  194. .target_cpus = x2apic_cluster_target_cpus,
  195. .disable_esr = 0,
  196. .dest_logical = APIC_DEST_LOGICAL,
  197. .check_apicid_used = NULL,
  198. .vector_allocation_domain = cluster_vector_allocation_domain,
  199. .init_apic_ldr = init_x2apic_ldr,
  200. .ioapic_phys_id_map = NULL,
  201. .setup_apic_routing = NULL,
  202. .cpu_present_to_apicid = default_cpu_present_to_apicid,
  203. .apicid_to_cpu_present = NULL,
  204. .check_phys_apicid_present = default_check_phys_apicid_present,
  205. .phys_pkg_id = x2apic_phys_pkg_id,
  206. .get_apic_id = x2apic_get_apic_id,
  207. .set_apic_id = x2apic_set_apic_id,
  208. .cpu_mask_to_apicid = x2apic_cpu_mask_to_apicid,
  209. .send_IPI = x2apic_send_IPI,
  210. .send_IPI_mask = x2apic_send_IPI_mask,
  211. .send_IPI_mask_allbutself = x2apic_send_IPI_mask_allbutself,
  212. .send_IPI_allbutself = x2apic_send_IPI_allbutself,
  213. .send_IPI_all = x2apic_send_IPI_all,
  214. .send_IPI_self = x2apic_send_IPI_self,
  215. .inquire_remote_apic = NULL,
  216. .read = native_apic_msr_read,
  217. .write = native_apic_msr_write,
  218. .eoi_write = native_apic_msr_eoi_write,
  219. .icr_read = native_x2apic_icr_read,
  220. .icr_write = native_x2apic_icr_write,
  221. .wait_icr_idle = native_x2apic_wait_icr_idle,
  222. .safe_wait_icr_idle = native_safe_x2apic_wait_icr_idle,
  223. };
  224. apic_driver(apic_x2apic_cluster);