[patch 07/10] Vertical cpu management.

From: Martin Schwidefsky
Date: Wed Mar 12 2008 - 13:34:29 EST


From: Heiko Carstens <heiko.carstens@xxxxxxxxxx>

Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---

arch/s390/kernel/smp.c | 83 ++++++++++++++++++++++++++++++++++++++++++--
arch/s390/kernel/topology.c | 66 +++++++++++++++++++++++++++++-----
include/asm-s390/smp.h | 1
include/asm-s390/topology.h | 9 ++++
4 files changed, 146 insertions(+), 13 deletions(-)

Index: quilt-2.6/arch/s390/kernel/smp.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/smp.c
+++ quilt-2.6/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_
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_
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(struc
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_attr
&attr_configure.attr,
#endif
&attr_address.attr,
+ &attr_polarization.attr,
NULL,
};

@@ -1073,11 +1111,48 @@ static ssize_t __ref rescan_store(struct
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)
Index: quilt-2.6/arch/s390/kernel/topology.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/topology.c
+++ quilt-2.6/arch/s390/kernel/topology.c
@@ -18,9 +18,17 @@
#include <asm/s390_ext.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];
};
@@ -35,8 +43,6 @@ union tl_entry {
struct tl_container container;
};

-#define NR_MAG 6
-
struct tl_info {
unsigned char reserved0[2];
unsigned short length;
@@ -95,8 +101,10 @@ static void add_cpus_to_core(struct tl_c

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;
+ }
}
}
}
@@ -151,7 +159,17 @@ static void tl_to_cores(struct tl_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;

@@ -160,7 +178,25 @@ 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;
}

@@ -170,9 +206,10 @@ 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) {
@@ -186,10 +223,15 @@ static void topology_work_fn(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();
}

@@ -210,8 +252,10 @@ static int __init init_topology_update(v
{
int rc;

- if (!machine_has_topology)
+ if (!machine_has_topology) {
+ topology_update_polarization_simple();
return 0;
+ }
init_timer(&topology_timer);
if (machine_has_topology_irq) {
rc = register_external_interrupt(0x2005, topology_interrupt);
Index: quilt-2.6/include/asm-s390/smp.h
===================================================================
--- quilt-2.6.orig/include/asm-s390/smp.h
+++ quilt-2.6/include/asm-s390/smp.h
@@ -91,6 +91,7 @@ extern void cpu_die (void) __attribute__
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);
Index: quilt-2.6/include/asm-s390/topology.h
===================================================================
--- quilt-2.6.orig/include/asm-s390/topology.h
+++ quilt-2.6/include/asm-s390/topology.h
@@ -9,6 +9,15 @@ cpumask_t cpu_coregroup_map(unsigned int

#define topology_core_siblings(cpu) (cpu_coregroup_map(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

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.

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