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[S390] Limit cpu detection to 256 physical cpus.

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Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens 2009-09-11 10:29:03 +02:00 committed by Martin Schwidefsky
parent 53f8c573ea
commit 4bb5e07b68
4 changed files with 13 additions and 7 deletions
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6
arch/s390/include/asm/cpu.h Normal file
View file

@ -0,0 +1,6 @@
#ifndef _ASM_S390_CPU_H
#define _ASM_S390_CPU_H
#define MAX_CPU_ADDRESS 255
#endif /* _ASM_S390_CPU_H */

1
arch/s390/kernel/head.S
View file

@ -27,6 +27,7 @@
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/page.h>
#include <asm/cpu.h>
#ifdef CONFIG_64BIT
#define ARCH_OFFSET 4

8
arch/s390/kernel/head64.S
View file

@ -62,9 +62,9 @@ startup_continue:
clr %r11,%r12
je 5f # no more space in prefix array
4:
ahi %r8,1 # next cpu (r8 += 1)
cl %r8,.Llast_cpu-.LPG1(%r13) # is last possible cpu ?
jl 1b # jump if not last cpu
ahi %r8,1 # next cpu (r8 += 1)
chi %r8,MAX_CPU_ADDRESS # is last possible cpu ?
jle 1b # jump if not last cpu
5:
lhi %r1,2 # mode 2 = esame (dump)
j 6f
@ -130,8 +130,6 @@ startup_continue:
#ifdef CONFIG_ZFCPDUMP
.Lcurrent_cpu:
.long 0x0
.Llast_cpu:
.long 0x0000ffff
.Lpref_arr_ptr:
.long zfcpdump_prefix_array
#endif /* CONFIG_ZFCPDUMP */

5
arch/s390/kernel/smp.c
View file

@ -49,6 +49,7 @@
#include <asm/sclp.h>
#include <asm/cputime.h>
#include <asm/vdso.h>
#include <asm/cpu.h>
#include "entry.h"
static struct task_struct *current_set[NR_CPUS];
@ -300,7 +301,7 @@ static int smp_rescan_cpus_sigp(cpumask_t avail)
logical_cpu = cpumask_first(&avail);
if (logical_cpu >= nr_cpu_ids)
return 0;
for (cpu_id = 0; cpu_id <= 65535; cpu_id++) {
for (cpu_id = 0; cpu_id <= MAX_CPU_ADDRESS; cpu_id++) {
if (cpu_known(cpu_id))
continue;
__cpu_logical_map[logical_cpu] = cpu_id;
@ -379,7 +380,7 @@ static void __init smp_detect_cpus(void)
/* Use sigp detection algorithm if sclp doesn't work. */
if (sclp_get_cpu_info(info)) {
smp_use_sigp_detection = 1;
for (cpu = 0; cpu <= 65535; cpu++) {
for (cpu = 0; cpu <= MAX_CPU_ADDRESS; cpu++) {
if (cpu == boot_cpu_addr)
continue;
__cpu_logical_map[CPU_INIT_NO] = cpu;