4 files changed, 148 insertions, 17 deletions

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 5448aa87fa23..d1e8e8a3fb66 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -68,7 +68,9 @@ enum s390_cpu_state {
 };
 
 DEFINE_MUTEX(smp_cpu_state_mutex);
+int smp_cpu_polarization[NR_CPUS];
 static int smp_cpu_state[NR_CPUS];
+static int cpu_management;
 
 static DEFINE_PER_CPU(struct cpu, cpu_devices);
 DEFINE_PER_CPU(struct s390_idle_data, s390_idle);
@@ -454,6 +456,7 @@ static int smp_rescan_cpus_sigp(cpumask_t avail)
                 if (cpu_known(cpu_id))
                         continue;
                 __cpu_logical_map[logical_cpu] = cpu_id;
+                smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN;
                 if (!cpu_stopped(logical_cpu))
                         continue;
                 cpu_set(logical_cpu, cpu_present_map);
@@ -487,6 +490,7 @@ static int smp_rescan_cpus_sclp(cpumask_t avail)
                 if (cpu_known(cpu_id))
                         continue;
                 __cpu_logical_map[logical_cpu] = cpu_id;
+                smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN;
                 cpu_set(logical_cpu, cpu_present_map);
                 if (cpu >= info->configured)
                         smp_cpu_state[logical_cpu] = CPU_STATE_STANDBY;
@@ -844,6 +848,7 @@ void __init smp_prepare_boot_cpu(void)
         S390_lowcore.percpu_offset = __per_cpu_offset[0];
         current_set[0] = current;
         smp_cpu_state[0] = CPU_STATE_CONFIGURED;
+        smp_cpu_polarization[0] = POLARIZATION_UNKNWN;
         spin_lock_init(&(&__get_cpu_var(s390_idle))->lock);
 }
 
@@ -895,15 +900,19 @@ static ssize_t cpu_configure_store(struct sys_device *dev, const char *buf,
         case 0:
                 if (smp_cpu_state[cpu] == CPU_STATE_CONFIGURED) {
                         rc = sclp_cpu_deconfigure(__cpu_logical_map[cpu]);
-                        if (!rc)
+                        if (!rc) {
                                 smp_cpu_state[cpu] = CPU_STATE_STANDBY;
+                                smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
+                        }
                 }
                 break;
         case 1:
                 if (smp_cpu_state[cpu] == CPU_STATE_STANDBY) {
                         rc = sclp_cpu_configure(__cpu_logical_map[cpu]);
-                        if (!rc)
+                        if (!rc) {
                                 smp_cpu_state[cpu] = CPU_STATE_CONFIGURED;
+                                smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
+                        }
                 }
                 break;
         default:
@@ -917,6 +926,34 @@ out:
 static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store);
 #endif /* CONFIG_HOTPLUG_CPU */
 
+static ssize_t cpu_polarization_show(struct sys_device *dev, char *buf)
+{
+        int cpu = dev->id;
+        ssize_t count;
+
+        mutex_lock(&smp_cpu_state_mutex);
+        switch (smp_cpu_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 SYSDEV_ATTR(polarization, 0444, cpu_polarization_show, NULL);
+
 static ssize_t show_cpu_address(struct sys_device *dev, char *buf)
 {
         return sprintf(buf, "%d\n", __cpu_logical_map[dev->id]);
@@ -929,6 +966,7 @@ static struct attribute *cpu_common_attrs[] = {
         &attr_configure.attr,
 #endif
         &attr_address.attr,
+        &attr_polarization.attr,
         NULL,
 };
 
@@ -1073,11 +1111,48 @@ static ssize_t __ref rescan_store(struct sys_device *dev,
 out:
         put_online_cpus();
         mutex_unlock(&smp_cpu_state_mutex);
+        if (!cpus_empty(newcpus))
+                topology_schedule_update();
         return rc ? rc : count;
 }
 static SYSDEV_ATTR(rescan, 0200, NULL, rescan_store);
 #endif /* CONFIG_HOTPLUG_CPU */
 
+static ssize_t dispatching_show(struct sys_device *dev, 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 sys_device *dev, 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;
+        mutex_lock(&smp_cpu_state_mutex);
+        get_online_cpus();
+        if (cpu_management == val)
+                goto out;
+        rc = topology_set_cpu_management(val);
+        if (!rc)
+                cpu_management = val;
+out:
+        put_online_cpus();
+        mutex_unlock(&smp_cpu_state_mutex);
+        return rc ? rc : count;
+}
+static SYSDEV_ATTR(dispatching, 0644, dispatching_show, dispatching_store);
+
 static int __init topology_init(void)
 {
         int cpu;
@@ -1091,6 +1166,10 @@ static int __init topology_init(void)
         if (rc)
                 return rc;
 #endif
+        rc = sysfs_create_file(&cpu_sysdev_class.kset.kobj,
+                               &attr_dispatching.attr);
+        if (rc)
+                return rc;
         for_each_present_cpu(cpu) {
                 rc = smp_add_present_cpu(cpu);
                 if (rc)
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index 369dc1c3bd10..12b39b3d9c38 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -1,6 +1,4 @@
 /*
- *  arch/s390/kernel/topology.c
- *
  *    Copyright IBM Corp. 2007
  *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
  */
@@ -19,9 +17,17 @@
 #include <asm/sysinfo.h>
 
 #define CPU_BITS 64
+#define NR_MAG 6
+
+#define PTF_HORIZONTAL  (0UL)
+#define PTF_VERTICAL    (1UL)
+#define PTF_CHECK       (2UL)
 
 struct tl_cpu {
-        unsigned char reserved[6];
+        unsigned char reserved0[4];
+        unsigned char :6;
+        unsigned char pp:2;
+        unsigned char reserved1;
         unsigned short origin;
         unsigned long mask[CPU_BITS / BITS_PER_LONG];
 };
@@ -36,8 +42,6 @@ union tl_entry {
         struct tl_container container;
 };
 
-#define NR_MAG 6
-
 struct tl_info {
         unsigned char reserved0[2];
         unsigned short length;
@@ -96,8 +100,10 @@ static void add_cpus_to_core(struct tl_cpu *tl_cpu, struct core_info *core)
 
                 rcpu = CPU_BITS - 1 - cpu + tl_cpu->origin;
                 for_each_present_cpu(lcpu) {
-                        if (__cpu_logical_map[lcpu] == rcpu)
+                        if (__cpu_logical_map[lcpu] == rcpu) {
                                 cpu_set(lcpu, core->mask);
+                                smp_cpu_polarization[lcpu] = tl_cpu->pp;
+                        }
                 }
         }
 }
@@ -127,7 +133,7 @@ static void tl_to_cores(struct tl_info *info)
 
         mutex_lock(&smp_cpu_state_mutex);
         clear_cores();
-        tle = (union tl_entry *)&info->tle;
+        tle = info->tle;
         end = (union tl_entry *)((unsigned long)info + info->length);
         while (tle < end) {
                 switch (tle->nl) {
@@ -152,7 +158,17 @@ static void tl_to_cores(struct tl_info *info)
         mutex_unlock(&smp_cpu_state_mutex);
 }
 
-static int ptf(void)
+static void topology_update_polarization_simple(void)
+{
+        int cpu;
+
+        mutex_lock(&smp_cpu_state_mutex);
+        for_each_present_cpu(cpu)
+                smp_cpu_polarization[cpu] = POLARIZATION_HRZ;
+        mutex_unlock(&smp_cpu_state_mutex);
+}
+
+static int ptf(unsigned long fc)
 {
         int rc;
 
@@ -161,7 +177,25 @@ static int ptf(void)
                 "       ipm     %0\n"
                 "       srl     %0,28\n"
                 : "=d" (rc)
-                : "d" (2UL)  : "cc");
+                : "d" (fc)  : "cc");
+        return rc;
+}
+
+int topology_set_cpu_management(int fc)
+{
+        int cpu;
+        int rc;
+
+        if (!machine_has_topology)
+                return -EOPNOTSUPP;
+        if (fc)
+                rc = ptf(PTF_VERTICAL);
+        else
+                rc = ptf(PTF_HORIZONTAL);
+        if (rc)
+                return -EBUSY;
+        for_each_present_cpu(cpu)
+                smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
         return rc;
 }
 
@@ -171,9 +205,10 @@ void arch_update_cpu_topology(void)
         struct sys_device *sysdev;
         int cpu;
 
-        if (!machine_has_topology)
+        if (!machine_has_topology) {
+                topology_update_polarization_simple();
                 return;
-        ptf();
+        }
         stsi(info, 15, 1, 2);
         tl_to_cores(info);
         for_each_online_cpu(cpu) {
@@ -187,10 +222,15 @@ static void topology_work_fn(struct work_struct *work)
         arch_reinit_sched_domains();
 }
 
+void topology_schedule_update(void)
+{
+        schedule_work(&topology_work);
+}
+
 static void topology_timer_fn(unsigned long ignored)
 {
-        if (ptf())
-                schedule_work(&topology_work);
+        if (ptf(PTF_CHECK))
+                topology_schedule_update();
         set_topology_timer();
 }
 
@@ -211,9 +251,11 @@ static int __init init_topology_update(void)
 {
         int rc;
 
-        if (!machine_has_topology)
+        if (!machine_has_topology) {
+                topology_update_polarization_simple();
                 return 0;
-        init_timer(&topology_timer);
+        }
+        init_timer_deferrable(&topology_timer);
         if (machine_has_topology_irq) {
                 rc = register_external_interrupt(0x2005, topology_interrupt);
                 if (rc)
diff --git a/include/asm-s390/smp.h b/include/asm-s390/smp.h
index a464a66c65d3..6f3821a6a902 100644
--- a/include/asm-s390/smp.h
+++ b/include/asm-s390/smp.h
@@ -91,6 +91,7 @@ extern void cpu_die (void) __attribute__ ((noreturn));
 extern int __cpu_up (unsigned int cpu);
 
 extern struct mutex smp_cpu_state_mutex;
+extern int smp_cpu_polarization[];
 
 extern int smp_call_function_mask(cpumask_t mask, void (*func)(void *),
         void *info, int wait);
diff --git a/include/asm-s390/topology.h b/include/asm-s390/topology.h
index 3b28a09a2108..8e97b06f298a 100644
--- a/include/asm-s390/topology.h
+++ b/include/asm-s390/topology.h
@@ -7,6 +7,15 @@
 
 cpumask_t cpu_coregroup_map(unsigned int cpu);
 
+int topology_set_cpu_management(int fc);
+void topology_schedule_update(void);
+
+#define POLARIZATION_UNKNWN     (-1)
+#define POLARIZATION_HRZ        (0)
+#define POLARIZATION_VL         (1)
+#define POLARIZATION_VM         (2)
+#define POLARIZATION_VH         (3)
+
 #ifdef CONFIG_SMP
 void s390_init_cpu_topology(void);
 #else