--- /dev/null
+#include <linux/threads.h>
+#include <linux/cpumask.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/dmar.h>
+#include <linux/cpu.h>
+
+#include <asm/smp.h>
+#include <asm/x2apic.h>
+
+static DEFINE_PER_CPU(u32, x86_cpu_to_logical_apicid);
+static DEFINE_PER_CPU(cpumask_var_t, cpus_in_cluster);
+static DEFINE_PER_CPU(cpumask_var_t, ipi_mask);
+
+static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
+{
+ return x2apic_enabled();
+}
+
+static inline u32 x2apic_cluster(int cpu)
+{
+ return per_cpu(x86_cpu_to_logical_apicid, cpu) >> 16;
+}
+
+static void
+__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
+{
+ struct cpumask *cpus_in_cluster_ptr;
+ struct cpumask *ipi_mask_ptr;
+ unsigned int cpu, this_cpu;
+ unsigned long flags;
+ u32 dest;
+
+ x2apic_wrmsr_fence();
+
+ local_irq_save(flags);
+
+ this_cpu = smp_processor_id();
+
+ /*
+ * We are to modify mask, so we need an own copy
+ * and be sure it's manipulated with irq off.
+ */
+ ipi_mask_ptr = this_cpu_cpumask_var_ptr(ipi_mask);
+ cpumask_copy(ipi_mask_ptr, mask);
+
+ /*
+ * The idea is to send one IPI per cluster.
+ */
+ for_each_cpu(cpu, ipi_mask_ptr) {
+ unsigned long i;
+
+ cpus_in_cluster_ptr = per_cpu(cpus_in_cluster, cpu);
+ dest = 0;
+
+ /* Collect cpus in cluster. */
+ for_each_cpu_and(i, ipi_mask_ptr, cpus_in_cluster_ptr) {
+ if (apic_dest == APIC_DEST_ALLINC || i != this_cpu)
+ dest |= per_cpu(x86_cpu_to_logical_apicid, i);
+ }
+
+ if (!dest)
+ continue;
+
+ __x2apic_send_IPI_dest(dest, vector, apic->dest_logical);
+ /*
+ * Cluster sibling cpus should be discared now so
+ * we would not send IPI them second time.
+ */
+ cpumask_andnot(ipi_mask_ptr, ipi_mask_ptr, cpus_in_cluster_ptr);
+ }
+
+ local_irq_restore(flags);
+}
+
+static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
+{
+ __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
+}
+
+static void
+x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
+{
+ __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
+}
+
+static void x2apic_send_IPI_allbutself(int vector)
+{
+ __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLBUT);
+}
+
+static void x2apic_send_IPI_all(int vector)
+{
+ __x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
+}
+
+static int
+x2apic_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
+ const struct cpumask *andmask,
+ unsigned int *apicid)
+{
+ u32 dest = 0;
+ u16 cluster;
+ int i;
+
+ for_each_cpu_and(i, cpumask, andmask) {
+ if (!cpumask_test_cpu(i, cpu_online_mask))
+ continue;
+ dest = per_cpu(x86_cpu_to_logical_apicid, i);
+ cluster = x2apic_cluster(i);
+ break;
+ }
+
+ if (!dest)
+ return -EINVAL;
+
+ for_each_cpu_and(i, cpumask, andmask) {
+ if (!cpumask_test_cpu(i, cpu_online_mask))
+ continue;
+ if (cluster != x2apic_cluster(i))
+ continue;
+ dest |= per_cpu(x86_cpu_to_logical_apicid, i);
+ }
+
+ *apicid = dest;
+
+ return 0;
+}
+
+static void init_x2apic_ldr(void)
+{
+ unsigned int this_cpu = smp_processor_id();
+ unsigned int cpu;
+
+ per_cpu(x86_cpu_to_logical_apicid, this_cpu) = apic_read(APIC_LDR);
+
+ cpumask_set_cpu(this_cpu, per_cpu(cpus_in_cluster, this_cpu));
+ for_each_online_cpu(cpu) {
+ if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu))
+ continue;
+ cpumask_set_cpu(this_cpu, per_cpu(cpus_in_cluster, cpu));
+ cpumask_set_cpu(cpu, per_cpu(cpus_in_cluster, this_cpu));
+ }
+}
+
+ /*
+ * At CPU state changes, update the x2apic cluster sibling info.
+ */
+static int
+update_clusterinfo(struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+ unsigned int this_cpu = (unsigned long)hcpu;
+ unsigned int cpu;
+ int err = 0;
+
+ switch (action) {
+ case CPU_UP_PREPARE:
+ if (!zalloc_cpumask_var(&per_cpu(cpus_in_cluster, this_cpu),
+ GFP_KERNEL)) {
+ err = -ENOMEM;
+ } else if (!zalloc_cpumask_var(&per_cpu(ipi_mask, this_cpu),
+ GFP_KERNEL)) {
+ free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu));
+ err = -ENOMEM;
+ }
+ break;
+ case CPU_UP_CANCELED:
+ case CPU_UP_CANCELED_FROZEN:
+ case CPU_DEAD:
+ for_each_online_cpu(cpu) {
+ if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu))
+ continue;
+ cpumask_clear_cpu(this_cpu, per_cpu(cpus_in_cluster, cpu));
+ cpumask_clear_cpu(cpu, per_cpu(cpus_in_cluster, this_cpu));
+ }
+ free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu));
+ free_cpumask_var(per_cpu(ipi_mask, this_cpu));
+ break;
+ }
+
+ return notifier_from_errno(err);
+}
+
+static struct notifier_block __refdata x2apic_cpu_notifier = {
+ .notifier_call = update_clusterinfo,
+};
+
+static int x2apic_init_cpu_notifier(void)
+{
+ int cpu = smp_processor_id();
+
+ zalloc_cpumask_var(&per_cpu(cpus_in_cluster, cpu), GFP_KERNEL);
+ zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL);
+
+ BUG_ON(!per_cpu(cpus_in_cluster, cpu) || !per_cpu(ipi_mask, cpu));
+
+ cpumask_set_cpu(cpu, per_cpu(cpus_in_cluster, cpu));
+ register_hotcpu_notifier(&x2apic_cpu_notifier);
+ return 1;
+}
+
+static int x2apic_cluster_probe(void)
+{
+ if (x2apic_mode)
+ return x2apic_init_cpu_notifier();
+ else
+ return 0;
+}
+
+static const struct cpumask *x2apic_cluster_target_cpus(void)
+{
+ return cpu_all_mask;
+}
+
+/*
+ * Each x2apic cluster is an allocation domain.
+ */
+static void cluster_vector_allocation_domain(int cpu, struct cpumask *retmask,
+ const struct cpumask *mask)
+{
+ /*
+ * To minimize vector pressure, default case of boot, device bringup
+ * etc will use a single cpu for the interrupt destination.
+ *
+ * On explicit migration requests coming from irqbalance etc,
+ * interrupts will be routed to the x2apic cluster (cluster-id
+ * derived from the first cpu in the mask) members specified
+ * in the mask.
+ */
+ if (mask == x2apic_cluster_target_cpus())
+ cpumask_copy(retmask, cpumask_of(cpu));
+ else
+ cpumask_and(retmask, mask, per_cpu(cpus_in_cluster, cpu));
+}
+
+static struct apic apic_x2apic_cluster = {
+
+ .name = "cluster x2apic",
+ .probe = x2apic_cluster_probe,
+ .acpi_madt_oem_check = x2apic_acpi_madt_oem_check,
+ .apic_id_valid = x2apic_apic_id_valid,
+ .apic_id_registered = x2apic_apic_id_registered,
+
+ .irq_delivery_mode = dest_LowestPrio,
+ .irq_dest_mode = 1, /* logical */
+
+ .target_cpus = x2apic_cluster_target_cpus,
+ .disable_esr = 0,
+ .dest_logical = APIC_DEST_LOGICAL,
+ .check_apicid_used = NULL,
+
+ .vector_allocation_domain = cluster_vector_allocation_domain,
+ .init_apic_ldr = init_x2apic_ldr,
+
+ .ioapic_phys_id_map = NULL,
+ .setup_apic_routing = NULL,
+ .cpu_present_to_apicid = default_cpu_present_to_apicid,
+ .apicid_to_cpu_present = NULL,
+ .check_phys_apicid_present = default_check_phys_apicid_present,
+ .phys_pkg_id = x2apic_phys_pkg_id,
+
+ .get_apic_id = x2apic_get_apic_id,
+ .set_apic_id = x2apic_set_apic_id,
+ .apic_id_mask = 0xFFFFFFFFu,
+
+ .cpu_mask_to_apicid_and = x2apic_cpu_mask_to_apicid_and,
+
+ .send_IPI_mask = x2apic_send_IPI_mask,
+ .send_IPI_mask_allbutself = x2apic_send_IPI_mask_allbutself,
+ .send_IPI_allbutself = x2apic_send_IPI_allbutself,
+ .send_IPI_all = x2apic_send_IPI_all,
+ .send_IPI_self = x2apic_send_IPI_self,
+
+ .wait_for_init_deassert = false,
+ .inquire_remote_apic = NULL,
+
+ .read = native_apic_msr_read,
+ .write = native_apic_msr_write,
+ .eoi_write = native_apic_msr_eoi_write,
+ .icr_read = native_x2apic_icr_read,
+ .icr_write = native_x2apic_icr_write,
+ .wait_icr_idle = native_x2apic_wait_icr_idle,
+ .safe_wait_icr_idle = native_safe_x2apic_wait_icr_idle,
+};
+
+apic_driver(apic_x2apic_cluster);
Code Review / kvmfornfv.git / blobdiff