Initial import

1 files changed, 287 insertions, 0 deletions

diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c
new file mode 100644
index 000000000..ab3219b3f
--- /dev/null
+++ b/arch/x86/kernel/apic/x2apic_cluster.c
@@ -0,0 +1,287 @@
+#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);