[patch 01/14] s390: move machine flags to lowcore

From: Martin Schwidefsky
Date: Tue Apr 14 2009 - 09:54:46 EST

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From: Christian Ehrhardt <ehrhardt@xxxxxxxxxxxxxxxxxx>

Currently the storage of the machine flags is a globally exported unsigned
long long variable. By moving the storage location into the lowcore struct we
allow assembler code to check machine_flags directly even without needing a
register. Addtionally the lowcore and therefore the machine flags too will be
in cache most of the time.

Signed-off-by: Christian Ehrhardt <ehrhardt@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---

arch/s390/include/asm/cpuid.h | 25 +++++++++++++++++++++++++
arch/s390/include/asm/kvm_host.h | 1 +
arch/s390/include/asm/lowcore.h | 12 ++++++++----
arch/s390/include/asm/processor.h | 17 +++--------------
arch/s390/include/asm/ptrace.h | 2 --
arch/s390/include/asm/setup.h | 24 ++++++++++++------------
arch/s390/include/asm/thread_info.h | 3 ++-
arch/s390/kernel/early.c | 3 +++
arch/s390/kernel/setup.c | 4 +---
arch/s390/kernel/smp.c | 1 +
10 files changed, 56 insertions(+), 36 deletions(-)

Index: quilt-2.6/arch/s390/include/asm/cpuid.h
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/include/asm/cpuid.h
@@ -0,0 +1,25 @@
+/*
+ * Copyright IBM Corp. 2000,2009
+ * Author(s): Hartmut Penner <hp@xxxxxxxxxx>,
+ * Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
+ * Christian Ehrhardt <ehrhardt@xxxxxxxxxx>
+ */
+
+#ifndef _ASM_S390_CPUID_H_
+#define _ASM_S390_CPUID_H_
+
+/*
+ * CPU type and hardware bug flags. Kept separately for each CPU.
+ * Members of this structure are referenced in head.S, so think twice
+ * before touching them. [mj]
+ */
+
+typedef struct
+{
+ unsigned int version : 8;
+ unsigned int ident : 24;
+ unsigned int machine : 16;
+ unsigned int unused : 16;
+} __attribute__ ((packed)) cpuid_t;
+
+#endif /* _ASM_S390_CPUID_H_ */
Index: quilt-2.6/arch/s390/include/asm/kvm_host.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/kvm_host.h
+++ quilt-2.6/arch/s390/include/asm/kvm_host.h
@@ -15,6 +15,7 @@
#define ASM_KVM_HOST_H
#include <linux/kvm_host.h>
#include <asm/debug.h>
+#include <asm/cpuid.h>

#define KVM_MAX_VCPUS 64
#define KVM_MEMORY_SLOTS 32
Index: quilt-2.6/arch/s390/include/asm/lowcore.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/lowcore.h
+++ quilt-2.6/arch/s390/include/asm/lowcore.h
@@ -66,6 +66,7 @@
#define __LC_USER_EXEC_ASCE 0x02ac
#define __LC_CPUID 0x02b0
#define __LC_INT_CLOCK 0x02c8
+#define __LC_MACHINE_FLAGS 0x02d8
#define __LC_IRB 0x0300
#define __LC_PFAULT_INTPARM 0x0080
#define __LC_CPU_TIMER_SAVE_AREA 0x00d8
@@ -110,6 +111,7 @@
#define __LC_CPUID 0x0320
#define __LC_INT_CLOCK 0x0340
#define __LC_VDSO_PER_CPU 0x0350
+#define __LC_MACHINE_FLAGS 0x0358
#define __LC_IRB 0x0380
#define __LC_PASTE 0x03c0
#define __LC_PFAULT_INTPARM 0x11b8
@@ -127,9 +129,9 @@

#ifndef __ASSEMBLY__

-#include <asm/processor.h>
+#include <asm/cpuid.h>
+#include <asm/ptrace.h>
#include <linux/types.h>
-#include <asm/sigp.h>

void restart_int_handler(void);
void ext_int_handler(void);
@@ -277,7 +279,8 @@ struct _lowcore
__u32 ext_call_fast; /* 0x02c4 */
__u64 int_clock; /* 0x02c8 */
__u64 clock_comparator; /* 0x02d0 */
- __u8 pad_0x02d8[0x0300-0x02d8]; /* 0x02d8 */
+ __u32 machine_flags; /* 0x02d8 */
+ __u8 pad_0x02dc[0x0300-0x02dc]; /* 0x02dc */

/* Interrupt response block */
__u8 irb[64]; /* 0x0300 */
@@ -381,7 +384,8 @@ struct _lowcore
__u64 int_clock; /* 0x0340 */
__u64 clock_comparator; /* 0x0348 */
__u64 vdso_per_cpu_data; /* 0x0350 */
- __u8 pad_0x0358[0x0380-0x0358]; /* 0x0358 */
+ __u64 machine_flags; /* 0x0358 */
+ __u8 pad_0x0360[0x0380-0x0360]; /* 0x0360 */

/* Interrupt response block. */
__u8 irb[64]; /* 0x0380 */
Index: quilt-2.6/arch/s390/include/asm/processor.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/processor.h
+++ quilt-2.6/arch/s390/include/asm/processor.h
@@ -14,7 +14,10 @@
#define __ASM_S390_PROCESSOR_H

#include <linux/linkage.h>
+#include <asm/cpuid.h>
+#include <asm/page.h>
#include <asm/ptrace.h>
+#include <asm/setup.h>

#ifdef __KERNEL__
/*
@@ -23,20 +26,6 @@
*/
#define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })

-/*
- * CPU type and hardware bug flags. Kept separately for each CPU.
- * Members of this structure are referenced in head.S, so think twice
- * before touching them. [mj]
- */
-
-typedef struct
-{
- unsigned int version : 8;
- unsigned int ident : 24;
- unsigned int machine : 16;
- unsigned int unused : 16;
-} __attribute__ ((packed)) cpuid_t;
-
static inline void get_cpu_id(cpuid_t *ptr)
{
asm volatile("stidp 0(%1)" : "=m" (*ptr) : "a" (ptr));
Index: quilt-2.6/arch/s390/include/asm/ptrace.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/ptrace.h
+++ quilt-2.6/arch/s390/include/asm/ptrace.h
@@ -313,8 +313,6 @@ typedef struct

#ifdef __KERNEL__
-#include <asm/setup.h>
-#include <asm/page.h>

/*
* The pt_regs struct defines the way the registers are stored on
Index: quilt-2.6/arch/s390/include/asm/setup.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/setup.h
+++ quilt-2.6/arch/s390/include/asm/setup.h
@@ -14,6 +14,7 @@

#ifdef __KERNEL__

+#include <asm/lowcore.h>
#include <asm/types.h>

#define PARMAREA 0x10400
@@ -63,7 +64,6 @@ extern unsigned int s390_noexec;
/*
* Machine features detected in head.S
*/
-extern unsigned long machine_flags;

#define MACHINE_FLAG_VM (1UL << 0)
#define MACHINE_FLAG_IEEE (1UL << 1)
@@ -77,28 +77,28 @@ extern unsigned long machine_flags;
#define MACHINE_FLAG_HPAGE (1UL << 10)
#define MACHINE_FLAG_PFMF (1UL << 11)

-#define MACHINE_IS_VM (machine_flags & MACHINE_FLAG_VM)
-#define MACHINE_IS_KVM (machine_flags & MACHINE_FLAG_KVM)
-#define MACHINE_HAS_DIAG9C (machine_flags & MACHINE_FLAG_DIAG9C)
+#define MACHINE_IS_VM (S390_lowcore.machine_flags & MACHINE_FLAG_VM)
+#define MACHINE_IS_KVM (S390_lowcore.machine_flags & MACHINE_FLAG_KVM)
+#define MACHINE_HAS_DIAG9C (S390_lowcore.machine_flags & MACHINE_FLAG_DIAG9C)

#ifndef __s390x__
-#define MACHINE_HAS_IEEE (machine_flags & MACHINE_FLAG_IEEE)
-#define MACHINE_HAS_CSP (machine_flags & MACHINE_FLAG_CSP)
+#define MACHINE_HAS_IEEE (S390_lowcore.machine_flags & MACHINE_FLAG_IEEE)
+#define MACHINE_HAS_CSP (S390_lowcore.machine_flags & MACHINE_FLAG_CSP)
#define MACHINE_HAS_IDTE (0)
#define MACHINE_HAS_DIAG44 (1)
-#define MACHINE_HAS_MVPG (machine_flags & MACHINE_FLAG_MVPG)
+#define MACHINE_HAS_MVPG (S390_lowcore.machine_flags & MACHINE_FLAG_MVPG)
#define MACHINE_HAS_MVCOS (0)
#define MACHINE_HAS_HPAGE (0)
#define MACHINE_HAS_PFMF (0)
#else /* __s390x__ */
#define MACHINE_HAS_IEEE (1)
#define MACHINE_HAS_CSP (1)
-#define MACHINE_HAS_IDTE (machine_flags & MACHINE_FLAG_IDTE)
-#define MACHINE_HAS_DIAG44 (machine_flags & MACHINE_FLAG_DIAG44)
+#define MACHINE_HAS_IDTE (S390_lowcore.machine_flags & MACHINE_FLAG_IDTE)
+#define MACHINE_HAS_DIAG44 (S390_lowcore.machine_flags & MACHINE_FLAG_DIAG44)
#define MACHINE_HAS_MVPG (1)
-#define MACHINE_HAS_MVCOS (machine_flags & MACHINE_FLAG_MVCOS)
-#define MACHINE_HAS_HPAGE (machine_flags & MACHINE_FLAG_HPAGE)
-#define MACHINE_HAS_PFMF (machine_flags & MACHINE_FLAG_PFMF)
+#define MACHINE_HAS_MVCOS (S390_lowcore.machine_flags & MACHINE_FLAG_MVCOS)
+#define MACHINE_HAS_HPAGE (S390_lowcore.machine_flags & MACHINE_FLAG_HPAGE)
+#define MACHINE_HAS_PFMF (S390_lowcore.machine_flags & MACHINE_FLAG_PFMF)
#endif /* __s390x__ */

#define ZFCPDUMP_HSA_SIZE (32UL<<20)
Index: quilt-2.6/arch/s390/include/asm/thread_info.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/thread_info.h
+++ quilt-2.6/arch/s390/include/asm/thread_info.h
@@ -31,8 +31,9 @@
#define ASYNC_SIZE (PAGE_SIZE << ASYNC_ORDER)

#ifndef __ASSEMBLY__
-#include <asm/processor.h>
#include <asm/lowcore.h>
+#include <asm/page.h>
+#include <asm/processor.h>

/*
* low level task data that entry.S needs immediate access to
Index: quilt-2.6/arch/s390/kernel/early.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/early.c
+++ quilt-2.6/arch/s390/kernel/early.c
@@ -34,6 +34,8 @@

char kernel_nss_name[NSS_NAME_SIZE + 1];

+static unsigned long machine_flags;
+
static void __init setup_boot_command_line(void);

@@ -391,5 +393,6 @@ void __init startup_init(void)
setup_hpage();
sclp_facilities_detect();
detect_memory_layout(memory_chunk);
+ S390_lowcore.machine_flags = machine_flags;
lockdep_on();
}
Index: quilt-2.6/arch/s390/kernel/setup.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/setup.c
+++ quilt-2.6/arch/s390/kernel/setup.c
@@ -82,9 +82,6 @@ EXPORT_SYMBOL(console_devno);
unsigned int console_irq = -1;
EXPORT_SYMBOL(console_irq);

-unsigned long machine_flags;
-EXPORT_SYMBOL(machine_flags);
-
unsigned long elf_hwcap = 0;
char elf_platform[ELF_PLATFORM_SIZE];

@@ -426,6 +423,7 @@ setup_lowcore(void)
__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
lc->current_task = (unsigned long) init_thread_union.thread_info.task;
lc->thread_info = (unsigned long) &init_thread_union;
+ lc->machine_flags = S390_lowcore.machine_flags;
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE) {
lc->extended_save_area_addr = (__u32)
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
@@ -571,6 +571,7 @@ int __cpuinit __cpu_up(unsigned int cpu)
cpu_lowcore->current_task = (unsigned long) idle;
cpu_lowcore->cpu_nr = cpu;
cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce;
+ cpu_lowcore->machine_flags = S390_lowcore.machine_flags;
eieio();

while (signal_processor(cpu, sigp_restart) == sigp_busy)

--
blue skies,
Martin.

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

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Next message: Martin Schwidefsky: "[patch 05/14] extend virtual timer interface by mod_virt_timer_periodic"
Previous message: Martin Schwidefsky: "[patch 02/14] wire up preadv/pwritev system calls"
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Next in thread: Martin Schwidefsky: "[patch 05/14] extend virtual timer interface by mod_virt_timer_periodic"
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