diff options
| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2009-09-11 10:29:03 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2009-09-11 10:29:55 +0200 |
| commit | 4bb5e07b68565d7983108993aa23eccf5f1b35fe (patch) | |
| tree | a76f2d5933cc8d90878f3df2d29f09fbd952daca /arch/s390 | |
| parent | 53f8c573ea3b54b7e1b81d2cd403373b08103736 (diff) | |
| download | linux-4bb5e07b68565d7983108993aa23eccf5f1b35fe.tar.bz2 | |
[S390] Limit cpu detection to 256 physical cpus.
Saves us more than 65k pointless IPIs.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/include/asm/cpu.h | 6 | ||||
| -rw-r--r-- | arch/s390/kernel/head.S | 1 | ||||
| -rw-r--r-- | arch/s390/kernel/head64.S | 8 | ||||
| -rw-r--r-- | arch/s390/kernel/smp.c | 5 |
4 files changed, 13 insertions, 7 deletions
diff --git a/arch/s390/include/asm/cpu.h b/arch/s390/include/asm/cpu.h new file mode 100644 index 000000000000..702ad46841cf --- /dev/null +++ b/arch/s390/include/asm/cpu.h @@ -0,0 +1,6 @@ +#ifndef _ASM_S390_CPU_H +#define _ASM_S390_CPU_H + +#define MAX_CPU_ADDRESS 255 + +#endif /* _ASM_S390_CPU_H */ diff --git a/arch/s390/kernel/head.S b/arch/s390/kernel/head.S index ec6882348520..c52b4f7742fa 100644 --- a/arch/s390/kernel/head.S +++ b/arch/s390/kernel/head.S @@ -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 diff --git a/arch/s390/kernel/head64.S b/arch/s390/kernel/head64.S index bdcb3f05bcd1..6a250808092b 100644 --- a/arch/s390/kernel/head64.S +++ b/arch/s390/kernel/head64.S @@ -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 */ diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index be2cae083406..9261495ca2c3 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -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; |