Commit dbd70fb4 authored by Heiko Carstens's avatar Heiko Carstens
Browse files

[S390] cpu topology support for s390.



Add s390 backend so we can give the scheduler some hints about the
cpu topology.
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
parent 7b758389
......@@ -3,6 +3,10 @@
# see Documentation/kbuild/kconfig-language.txt.
#
config SCHED_MC
def_bool y
depends on SMP
config MMU
def_bool y
......
......@@ -3,6 +3,7 @@
# Linux kernel version: 2.6.25-rc4
# Wed Mar 5 11:22:59 2008
#
CONFIG_SCHED_MC=y
CONFIG_MMU=y
CONFIG_ZONE_DMA=y
CONFIG_LOCKDEP_SUPPORT=y
......
......@@ -19,7 +19,7 @@ obj-y += $(if $(CONFIG_64BIT),reipl64.o,reipl.o)
extra-y += head.o init_task.o vmlinux.lds
obj-$(CONFIG_MODULES) += s390_ksyms.o module.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_SMP) += smp.o topology.o
obj-$(CONFIG_AUDIT) += audit.o
compat-obj-$(CONFIG_AUDIT) += compat_audit.o
......
......@@ -39,6 +39,7 @@
#include <linux/pfn.h>
#include <linux/ctype.h>
#include <linux/reboot.h>
#include <linux/topology.h>
#include <asm/ipl.h>
#include <asm/uaccess.h>
......@@ -830,6 +831,7 @@ setup_arch(char **cmdline_p)
cpu_init();
__cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
s390_init_cpu_topology();
/*
* Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
......
......@@ -67,9 +67,7 @@ enum s390_cpu_state {
CPU_STATE_CONFIGURED,
};
#ifdef CONFIG_HOTPLUG_CPU
static DEFINE_MUTEX(smp_cpu_state_mutex);
#endif
DEFINE_MUTEX(smp_cpu_state_mutex);
static int smp_cpu_state[NR_CPUS];
static DEFINE_PER_CPU(struct cpu, cpu_devices);
......
/*
* arch/s390/kernel/topology.c
*
* Copyright IBM Corp. 2007
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/bootmem.h>
#include <linux/sched.h>
#include <linux/workqueue.h>
#include <linux/cpu.h>
#include <linux/smp.h>
#include <asm/delay.h>
#include <asm/s390_ext.h>
#include <asm/sysinfo.h>
#define CPU_BITS 64
struct tl_cpu {
unsigned char reserved[6];
unsigned short origin;
unsigned long mask[CPU_BITS / BITS_PER_LONG];
};
struct tl_container {
unsigned char reserved[8];
};
union tl_entry {
unsigned char nl;
struct tl_cpu cpu;
struct tl_container container;
};
#define NR_MAG 6
struct tl_info {
unsigned char reserved0[2];
unsigned short length;
unsigned char mag[NR_MAG];
unsigned char reserved1;
unsigned char mnest;
unsigned char reserved2[4];
union tl_entry tle[0];
};
struct core_info {
struct core_info *next;
cpumask_t mask;
};
static void topology_work_fn(struct work_struct *work);
static struct tl_info *tl_info;
static struct core_info core_info;
static int machine_has_topology;
static int machine_has_topology_irq;
static struct timer_list topology_timer;
static void set_topology_timer(void);
static DECLARE_WORK(topology_work, topology_work_fn);
cpumask_t cpu_coregroup_map(unsigned int cpu)
{
struct core_info *core = &core_info;
cpumask_t mask;
cpus_clear(mask);
if (!machine_has_topology)
return cpu_present_map;
mutex_lock(&smp_cpu_state_mutex);
while (core) {
if (cpu_isset(cpu, core->mask)) {
mask = core->mask;
break;
}
core = core->next;
}
mutex_unlock(&smp_cpu_state_mutex);
if (cpus_empty(mask))
mask = cpumask_of_cpu(cpu);
return mask;
}
static void add_cpus_to_core(struct tl_cpu *tl_cpu, struct core_info *core)
{
unsigned int cpu;
for (cpu = find_first_bit(&tl_cpu->mask[0], CPU_BITS);
cpu < CPU_BITS;
cpu = find_next_bit(&tl_cpu->mask[0], CPU_BITS, cpu + 1))
{
unsigned int rcpu, lcpu;
rcpu = CPU_BITS - 1 - cpu + tl_cpu->origin;
for_each_present_cpu(lcpu) {
if (__cpu_logical_map[lcpu] == rcpu)
cpu_set(lcpu, core->mask);
}
}
}
static void clear_cores(void)
{
struct core_info *core = &core_info;
while (core) {
cpus_clear(core->mask);
core = core->next;
}
}
static union tl_entry *next_tle(union tl_entry *tle)
{
if (tle->nl)
return (union tl_entry *)((struct tl_container *)tle + 1);
else
return (union tl_entry *)((struct tl_cpu *)tle + 1);
}
static void tl_to_cores(struct tl_info *info)
{
union tl_entry *tle, *end;
struct core_info *core = &core_info;
mutex_lock(&smp_cpu_state_mutex);
clear_cores();
tle = (union tl_entry *)&info->tle;
end = (union tl_entry *)((unsigned long)info + info->length);
while (tle < end) {
switch (tle->nl) {
case 5:
case 4:
case 3:
case 2:
break;
case 1:
core = core->next;
break;
case 0:
add_cpus_to_core(&tle->cpu, core);
break;
default:
clear_cores();
machine_has_topology = 0;
return;
}
tle = next_tle(tle);
}
mutex_unlock(&smp_cpu_state_mutex);
}
static int ptf(void)
{
int rc;
asm volatile(
" .insn rre,0xb9a20000,%1,%1\n"
" ipm %0\n"
" srl %0,28\n"
: "=d" (rc)
: "d" (2UL) : "cc");
return rc;
}
void arch_update_cpu_topology(void)
{
struct tl_info *info = tl_info;
struct sys_device *sysdev;
int cpu;
if (!machine_has_topology)
return;
ptf();
stsi(info, 15, 1, 2);
tl_to_cores(info);
for_each_online_cpu(cpu) {
sysdev = get_cpu_sysdev(cpu);
kobject_uevent(&sysdev->kobj, KOBJ_CHANGE);
}
}
static void topology_work_fn(struct work_struct *work)
{
arch_reinit_sched_domains();
}
static void topology_timer_fn(unsigned long ignored)
{
if (ptf())
schedule_work(&topology_work);
set_topology_timer();
}
static void set_topology_timer(void)
{
topology_timer.function = topology_timer_fn;
topology_timer.data = 0;
topology_timer.expires = jiffies + 60 * HZ;
add_timer(&topology_timer);
}
static void topology_interrupt(__u16 code)
{
schedule_work(&topology_work);
}
static int __init init_topology_update(void)
{
int rc;
if (!machine_has_topology)
return 0;
init_timer(&topology_timer);
if (machine_has_topology_irq) {
rc = register_external_interrupt(0x2005, topology_interrupt);
if (rc)
return rc;
ctl_set_bit(0, 8);
}
else
set_topology_timer();
return 0;
}
__initcall(init_topology_update);
void __init s390_init_cpu_topology(void)
{
unsigned long long facility_bits;
struct tl_info *info;
struct core_info *core;
int nr_cores;
int i;
if (stfle(&facility_bits, 1) <= 0)
return;
if (!(facility_bits & (1ULL << 52)) || !(facility_bits & (1ULL << 61)))
return;
machine_has_topology = 1;
if (facility_bits & (1ULL << 51))
machine_has_topology_irq = 1;
tl_info = alloc_bootmem_pages(PAGE_SIZE);
if (!tl_info)
goto error;
info = tl_info;
stsi(info, 15, 1, 2);
nr_cores = info->mag[NR_MAG - 2];
for (i = 0; i < info->mnest - 2; i++)
nr_cores *= info->mag[NR_MAG - 3 - i];
printk(KERN_INFO "CPU topology:");
for (i = 0; i < NR_MAG; i++)
printk(" %d", info->mag[i]);
printk(" / %d\n", info->mnest);
core = &core_info;
for (i = 0; i < nr_cores; i++) {
core->next = alloc_bootmem(sizeof(struct core_info));
core = core->next;
if (!core)
goto error;
}
return;
error:
machine_has_topology = 0;
machine_has_topology_irq = 0;
}
......@@ -90,6 +90,8 @@ extern void __cpu_die (unsigned int cpu);
extern void cpu_die (void) __attribute__ ((noreturn));
extern int __cpu_up (unsigned int cpu);
extern struct mutex smp_cpu_state_mutex;
extern int smp_call_function_mask(cpumask_t mask, void (*func)(void *),
void *info, int wait);
#endif
......
#ifndef _ASM_S390_TOPOLOGY_H
#define _ASM_S390_TOPOLOGY_H
#include <linux/cpumask.h>
#define mc_capable() (1)
cpumask_t cpu_coregroup_map(unsigned int cpu);
#ifdef CONFIG_SMP
void s390_init_cpu_topology(void);
#else
static inline void s390_init_cpu_topology(void)
{
};
#endif
#include <asm-generic/topology.h>
#endif /* _ASM_S390_TOPOLOGY_H */
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