v4.19.13 snapshot.
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
new file mode 100644
index 0000000..e8184a1
--- /dev/null
+++ b/arch/s390/kernel/topology.c
@@ -0,0 +1,640 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright IBM Corp. 2007, 2011
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#define KMSG_COMPONENT "cpu"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/workqueue.h>
+#include <linux/bootmem.h>
+#include <linux/uaccess.h>
+#include <linux/sysctl.h>
+#include <linux/cpuset.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/sched/topology.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+#include <linux/nodemask.h>
+#include <linux/node.h>
+#include <asm/sysinfo.h>
+#include <asm/numa.h>
+
+#define PTF_HORIZONTAL (0UL)
+#define PTF_VERTICAL (1UL)
+#define PTF_CHECK (2UL)
+
+enum {
+ TOPOLOGY_MODE_HW,
+ TOPOLOGY_MODE_SINGLE,
+ TOPOLOGY_MODE_PACKAGE,
+ TOPOLOGY_MODE_UNINITIALIZED
+};
+
+struct mask_info {
+ struct mask_info *next;
+ unsigned char id;
+ cpumask_t mask;
+};
+
+static int topology_mode = TOPOLOGY_MODE_UNINITIALIZED;
+static void set_topology_timer(void);
+static void topology_work_fn(struct work_struct *work);
+static struct sysinfo_15_1_x *tl_info;
+
+static DECLARE_WORK(topology_work, topology_work_fn);
+
+/*
+ * Socket/Book linked lists and cpu_topology updates are
+ * protected by "sched_domains_mutex".
+ */
+static struct mask_info socket_info;
+static struct mask_info book_info;
+static struct mask_info drawer_info;
+
+struct cpu_topology_s390 cpu_topology[NR_CPUS];
+EXPORT_SYMBOL_GPL(cpu_topology);
+
+cpumask_t cpus_with_topology;
+
+static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu)
+{
+ cpumask_t mask;
+
+ cpumask_copy(&mask, cpumask_of(cpu));
+ switch (topology_mode) {
+ case TOPOLOGY_MODE_HW:
+ while (info) {
+ if (cpumask_test_cpu(cpu, &info->mask)) {
+ mask = info->mask;
+ break;
+ }
+ info = info->next;
+ }
+ if (cpumask_empty(&mask))
+ cpumask_copy(&mask, cpumask_of(cpu));
+ break;
+ case TOPOLOGY_MODE_PACKAGE:
+ cpumask_copy(&mask, cpu_present_mask);
+ break;
+ default:
+ /* fallthrough */
+ case TOPOLOGY_MODE_SINGLE:
+ cpumask_copy(&mask, cpumask_of(cpu));
+ break;
+ }
+ return mask;
+}
+
+static cpumask_t cpu_thread_map(unsigned int cpu)
+{
+ cpumask_t mask;
+ int i;
+
+ cpumask_copy(&mask, cpumask_of(cpu));
+ if (topology_mode != TOPOLOGY_MODE_HW)
+ return mask;
+ cpu -= cpu % (smp_cpu_mtid + 1);
+ for (i = 0; i <= smp_cpu_mtid; i++)
+ if (cpu_present(cpu + i))
+ cpumask_set_cpu(cpu + i, &mask);
+ return mask;
+}
+
+#define TOPOLOGY_CORE_BITS 64
+
+static void add_cpus_to_mask(struct topology_core *tl_core,
+ struct mask_info *drawer,
+ struct mask_info *book,
+ struct mask_info *socket)
+{
+ struct cpu_topology_s390 *topo;
+ unsigned int core;
+
+ for_each_set_bit(core, &tl_core->mask, TOPOLOGY_CORE_BITS) {
+ unsigned int rcore;
+ int lcpu, i;
+
+ rcore = TOPOLOGY_CORE_BITS - 1 - core + tl_core->origin;
+ lcpu = smp_find_processor_id(rcore << smp_cpu_mt_shift);
+ if (lcpu < 0)
+ continue;
+ for (i = 0; i <= smp_cpu_mtid; i++) {
+ topo = &cpu_topology[lcpu + i];
+ topo->drawer_id = drawer->id;
+ topo->book_id = book->id;
+ topo->socket_id = socket->id;
+ topo->core_id = rcore;
+ topo->thread_id = lcpu + i;
+ topo->dedicated = tl_core->d;
+ cpumask_set_cpu(lcpu + i, &drawer->mask);
+ cpumask_set_cpu(lcpu + i, &book->mask);
+ cpumask_set_cpu(lcpu + i, &socket->mask);
+ cpumask_set_cpu(lcpu + i, &cpus_with_topology);
+ smp_cpu_set_polarization(lcpu + i, tl_core->pp);
+ }
+ }
+}
+
+static void clear_masks(void)
+{
+ struct mask_info *info;
+
+ info = &socket_info;
+ while (info) {
+ cpumask_clear(&info->mask);
+ info = info->next;
+ }
+ info = &book_info;
+ while (info) {
+ cpumask_clear(&info->mask);
+ info = info->next;
+ }
+ info = &drawer_info;
+ while (info) {
+ cpumask_clear(&info->mask);
+ info = info->next;
+ }
+}
+
+static union topology_entry *next_tle(union topology_entry *tle)
+{
+ if (!tle->nl)
+ return (union topology_entry *)((struct topology_core *)tle + 1);
+ return (union topology_entry *)((struct topology_container *)tle + 1);
+}
+
+static void tl_to_masks(struct sysinfo_15_1_x *info)
+{
+ struct mask_info *socket = &socket_info;
+ struct mask_info *book = &book_info;
+ struct mask_info *drawer = &drawer_info;
+ union topology_entry *tle, *end;
+
+ clear_masks();
+ tle = info->tle;
+ end = (union topology_entry *)((unsigned long)info + info->length);
+ while (tle < end) {
+ switch (tle->nl) {
+ case 3:
+ drawer = drawer->next;
+ drawer->id = tle->container.id;
+ break;
+ case 2:
+ book = book->next;
+ book->id = tle->container.id;
+ break;
+ case 1:
+ socket = socket->next;
+ socket->id = tle->container.id;
+ break;
+ case 0:
+ add_cpus_to_mask(&tle->cpu, drawer, book, socket);
+ break;
+ default:
+ clear_masks();
+ return;
+ }
+ tle = next_tle(tle);
+ }
+}
+
+static void topology_update_polarization_simple(void)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ smp_cpu_set_polarization(cpu, POLARIZATION_HRZ);
+}
+
+static int ptf(unsigned long fc)
+{
+ int rc;
+
+ asm volatile(
+ " .insn rre,0xb9a20000,%1,%1\n"
+ " ipm %0\n"
+ " srl %0,28\n"
+ : "=d" (rc)
+ : "d" (fc) : "cc");
+ return rc;
+}
+
+int topology_set_cpu_management(int fc)
+{
+ int cpu, rc;
+
+ if (!MACHINE_HAS_TOPOLOGY)
+ return -EOPNOTSUPP;
+ if (fc)
+ rc = ptf(PTF_VERTICAL);
+ else
+ rc = ptf(PTF_HORIZONTAL);
+ if (rc)
+ return -EBUSY;
+ for_each_possible_cpu(cpu)
+ smp_cpu_set_polarization(cpu, POLARIZATION_UNKNOWN);
+ return rc;
+}
+
+static void update_cpu_masks(void)
+{
+ struct cpu_topology_s390 *topo;
+ int cpu, id;
+
+ for_each_possible_cpu(cpu) {
+ topo = &cpu_topology[cpu];
+ topo->thread_mask = cpu_thread_map(cpu);
+ topo->core_mask = cpu_group_map(&socket_info, cpu);
+ topo->book_mask = cpu_group_map(&book_info, cpu);
+ topo->drawer_mask = cpu_group_map(&drawer_info, cpu);
+ if (topology_mode != TOPOLOGY_MODE_HW) {
+ id = topology_mode == TOPOLOGY_MODE_PACKAGE ? 0 : cpu;
+ topo->thread_id = cpu;
+ topo->core_id = cpu;
+ topo->socket_id = id;
+ topo->book_id = id;
+ topo->drawer_id = id;
+ if (cpu_present(cpu))
+ cpumask_set_cpu(cpu, &cpus_with_topology);
+ }
+ }
+ numa_update_cpu_topology();
+}
+
+void store_topology(struct sysinfo_15_1_x *info)
+{
+ stsi(info, 15, 1, topology_mnest_limit());
+}
+
+static void __arch_update_dedicated_flag(void *arg)
+{
+ if (topology_cpu_dedicated(smp_processor_id()))
+ set_cpu_flag(CIF_DEDICATED_CPU);
+ else
+ clear_cpu_flag(CIF_DEDICATED_CPU);
+}
+
+static int __arch_update_cpu_topology(void)
+{
+ struct sysinfo_15_1_x *info = tl_info;
+ int rc = 0;
+
+ mutex_lock(&smp_cpu_state_mutex);
+ cpumask_clear(&cpus_with_topology);
+ if (MACHINE_HAS_TOPOLOGY) {
+ rc = 1;
+ store_topology(info);
+ tl_to_masks(info);
+ }
+ update_cpu_masks();
+ if (!MACHINE_HAS_TOPOLOGY)
+ topology_update_polarization_simple();
+ mutex_unlock(&smp_cpu_state_mutex);
+ return rc;
+}
+
+int arch_update_cpu_topology(void)
+{
+ struct device *dev;
+ int cpu, rc;
+
+ rc = __arch_update_cpu_topology();
+ on_each_cpu(__arch_update_dedicated_flag, NULL, 0);
+ for_each_online_cpu(cpu) {
+ dev = get_cpu_device(cpu);
+ kobject_uevent(&dev->kobj, KOBJ_CHANGE);
+ }
+ return rc;
+}
+
+static void topology_work_fn(struct work_struct *work)
+{
+ rebuild_sched_domains();
+}
+
+void topology_schedule_update(void)
+{
+ schedule_work(&topology_work);
+}
+
+static void topology_flush_work(void)
+{
+ flush_work(&topology_work);
+}
+
+static void topology_timer_fn(struct timer_list *unused)
+{
+ if (ptf(PTF_CHECK))
+ topology_schedule_update();
+ set_topology_timer();
+}
+
+static struct timer_list topology_timer;
+
+static atomic_t topology_poll = ATOMIC_INIT(0);
+
+static void set_topology_timer(void)
+{
+ if (atomic_add_unless(&topology_poll, -1, 0))
+ mod_timer(&topology_timer, jiffies + HZ / 10);
+ else
+ mod_timer(&topology_timer, jiffies + HZ * 60);
+}
+
+void topology_expect_change(void)
+{
+ if (!MACHINE_HAS_TOPOLOGY)
+ return;
+ /* This is racy, but it doesn't matter since it is just a heuristic.
+ * Worst case is that we poll in a higher frequency for a bit longer.
+ */
+ if (atomic_read(&topology_poll) > 60)
+ return;
+ atomic_add(60, &topology_poll);
+ set_topology_timer();
+}
+
+static int cpu_management;
+
+static ssize_t dispatching_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ ssize_t count;
+
+ mutex_lock(&smp_cpu_state_mutex);
+ count = sprintf(buf, "%d\n", cpu_management);
+ mutex_unlock(&smp_cpu_state_mutex);
+ return count;
+}
+
+static ssize_t dispatching_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ int val, rc;
+ char delim;
+
+ if (sscanf(buf, "%d %c", &val, &delim) != 1)
+ return -EINVAL;
+ if (val != 0 && val != 1)
+ return -EINVAL;
+ rc = 0;
+ get_online_cpus();
+ mutex_lock(&smp_cpu_state_mutex);
+ if (cpu_management == val)
+ goto out;
+ rc = topology_set_cpu_management(val);
+ if (rc)
+ goto out;
+ cpu_management = val;
+ topology_expect_change();
+out:
+ mutex_unlock(&smp_cpu_state_mutex);
+ put_online_cpus();
+ return rc ? rc : count;
+}
+static DEVICE_ATTR_RW(dispatching);
+
+static ssize_t cpu_polarization_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int cpu = dev->id;
+ ssize_t count;
+
+ mutex_lock(&smp_cpu_state_mutex);
+ switch (smp_cpu_get_polarization(cpu)) {
+ case POLARIZATION_HRZ:
+ count = sprintf(buf, "horizontal\n");
+ break;
+ case POLARIZATION_VL:
+ count = sprintf(buf, "vertical:low\n");
+ break;
+ case POLARIZATION_VM:
+ count = sprintf(buf, "vertical:medium\n");
+ break;
+ case POLARIZATION_VH:
+ count = sprintf(buf, "vertical:high\n");
+ break;
+ default:
+ count = sprintf(buf, "unknown\n");
+ break;
+ }
+ mutex_unlock(&smp_cpu_state_mutex);
+ return count;
+}
+static DEVICE_ATTR(polarization, 0444, cpu_polarization_show, NULL);
+
+static struct attribute *topology_cpu_attrs[] = {
+ &dev_attr_polarization.attr,
+ NULL,
+};
+
+static struct attribute_group topology_cpu_attr_group = {
+ .attrs = topology_cpu_attrs,
+};
+
+static ssize_t cpu_dedicated_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int cpu = dev->id;
+ ssize_t count;
+
+ mutex_lock(&smp_cpu_state_mutex);
+ count = sprintf(buf, "%d\n", topology_cpu_dedicated(cpu));
+ mutex_unlock(&smp_cpu_state_mutex);
+ return count;
+}
+static DEVICE_ATTR(dedicated, 0444, cpu_dedicated_show, NULL);
+
+static struct attribute *topology_extra_cpu_attrs[] = {
+ &dev_attr_dedicated.attr,
+ NULL,
+};
+
+static struct attribute_group topology_extra_cpu_attr_group = {
+ .attrs = topology_extra_cpu_attrs,
+};
+
+int topology_cpu_init(struct cpu *cpu)
+{
+ int rc;
+
+ rc = sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group);
+ if (rc || !MACHINE_HAS_TOPOLOGY)
+ return rc;
+ rc = sysfs_create_group(&cpu->dev.kobj, &topology_extra_cpu_attr_group);
+ if (rc)
+ sysfs_remove_group(&cpu->dev.kobj, &topology_cpu_attr_group);
+ return rc;
+}
+
+static const struct cpumask *cpu_thread_mask(int cpu)
+{
+ return &cpu_topology[cpu].thread_mask;
+}
+
+
+const struct cpumask *cpu_coregroup_mask(int cpu)
+{
+ return &cpu_topology[cpu].core_mask;
+}
+
+static const struct cpumask *cpu_book_mask(int cpu)
+{
+ return &cpu_topology[cpu].book_mask;
+}
+
+static const struct cpumask *cpu_drawer_mask(int cpu)
+{
+ return &cpu_topology[cpu].drawer_mask;
+}
+
+static struct sched_domain_topology_level s390_topology[] = {
+ { cpu_thread_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
+ { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
+ { cpu_book_mask, SD_INIT_NAME(BOOK) },
+ { cpu_drawer_mask, SD_INIT_NAME(DRAWER) },
+ { cpu_cpu_mask, SD_INIT_NAME(DIE) },
+ { NULL, },
+};
+
+static void __init alloc_masks(struct sysinfo_15_1_x *info,
+ struct mask_info *mask, int offset)
+{
+ int i, nr_masks;
+
+ nr_masks = info->mag[TOPOLOGY_NR_MAG - offset];
+ for (i = 0; i < info->mnest - offset; i++)
+ nr_masks *= info->mag[TOPOLOGY_NR_MAG - offset - 1 - i];
+ nr_masks = max(nr_masks, 1);
+ for (i = 0; i < nr_masks; i++) {
+ mask->next = memblock_virt_alloc(sizeof(*mask->next), 8);
+ mask = mask->next;
+ }
+}
+
+void __init topology_init_early(void)
+{
+ struct sysinfo_15_1_x *info;
+
+ set_sched_topology(s390_topology);
+ if (topology_mode == TOPOLOGY_MODE_UNINITIALIZED) {
+ if (MACHINE_HAS_TOPOLOGY)
+ topology_mode = TOPOLOGY_MODE_HW;
+ else
+ topology_mode = TOPOLOGY_MODE_SINGLE;
+ }
+ if (!MACHINE_HAS_TOPOLOGY)
+ goto out;
+ tl_info = memblock_virt_alloc(PAGE_SIZE, PAGE_SIZE);
+ info = tl_info;
+ store_topology(info);
+ pr_info("The CPU configuration topology of the machine is: %d %d %d %d %d %d / %d\n",
+ info->mag[0], info->mag[1], info->mag[2], info->mag[3],
+ info->mag[4], info->mag[5], info->mnest);
+ alloc_masks(info, &socket_info, 1);
+ alloc_masks(info, &book_info, 2);
+ alloc_masks(info, &drawer_info, 3);
+out:
+ __arch_update_cpu_topology();
+ __arch_update_dedicated_flag(NULL);
+}
+
+static inline int topology_get_mode(int enabled)
+{
+ if (!enabled)
+ return TOPOLOGY_MODE_SINGLE;
+ return MACHINE_HAS_TOPOLOGY ? TOPOLOGY_MODE_HW : TOPOLOGY_MODE_PACKAGE;
+}
+
+static inline int topology_is_enabled(void)
+{
+ return topology_mode != TOPOLOGY_MODE_SINGLE;
+}
+
+static int __init topology_setup(char *str)
+{
+ bool enabled;
+ int rc;
+
+ rc = kstrtobool(str, &enabled);
+ if (rc)
+ return rc;
+ topology_mode = topology_get_mode(enabled);
+ return 0;
+}
+early_param("topology", topology_setup);
+
+static int topology_ctl_handler(struct ctl_table *ctl, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ int enabled = topology_is_enabled();
+ int new_mode;
+ int zero = 0;
+ int one = 1;
+ int rc;
+ struct ctl_table ctl_entry = {
+ .procname = ctl->procname,
+ .data = &enabled,
+ .maxlen = sizeof(int),
+ .extra1 = &zero,
+ .extra2 = &one,
+ };
+
+ rc = proc_douintvec_minmax(&ctl_entry, write, buffer, lenp, ppos);
+ if (rc < 0 || !write)
+ return rc;
+
+ mutex_lock(&smp_cpu_state_mutex);
+ new_mode = topology_get_mode(enabled);
+ if (topology_mode != new_mode) {
+ topology_mode = new_mode;
+ topology_schedule_update();
+ }
+ mutex_unlock(&smp_cpu_state_mutex);
+ topology_flush_work();
+
+ return rc;
+}
+
+static struct ctl_table topology_ctl_table[] = {
+ {
+ .procname = "topology",
+ .mode = 0644,
+ .proc_handler = topology_ctl_handler,
+ },
+ { },
+};
+
+static struct ctl_table topology_dir_table[] = {
+ {
+ .procname = "s390",
+ .maxlen = 0,
+ .mode = 0555,
+ .child = topology_ctl_table,
+ },
+ { },
+};
+
+static int __init topology_init(void)
+{
+ timer_setup(&topology_timer, topology_timer_fn, TIMER_DEFERRABLE);
+ if (MACHINE_HAS_TOPOLOGY)
+ set_topology_timer();
+ else
+ topology_update_polarization_simple();
+ register_sysctl_table(topology_dir_table);
+ return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching);
+}
+device_initcall(topology_init);