s390/idle: consolidate idle functions and definitions

Move the C functions and definitions related to the idle state handling
to arch/s390/include/asm/idle.h and arch/s390/kernel/idle.c. The function
s390_get_idle_time is renamed to arch_cpu_idle_time and vtime_stop_cpu to
enabled_wait.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

12 files changed, 166 insertions, 144 deletions

diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h
index 01887b1fade5..1c016a5fa97e 100644
--- a/arch/s390/include/asm/cputime.h
+++ b/arch/s390/include/asm/cputime.h
@@ -8,8 +8,6 @@
 #define _S390_CPUTIME_H
 
 #include <linux/types.h>
-#include <linux/percpu.h>
-#include <linux/spinlock.h>
 #include <asm/div64.h>
 
 
@@ -165,20 +163,8 @@ static inline clock_t cputime64_to_clock_t(cputime64_t cputime)
         return clock;
 }
 
-struct s390_idle_data {
-        unsigned int sequence;
-        unsigned long long idle_count;
-        unsigned long long idle_time;
-        unsigned long long clock_idle_enter;
-        unsigned long long clock_idle_exit;
-        unsigned long long timer_idle_enter;
-        unsigned long long timer_idle_exit;
-};
+cputime64_t arch_cpu_idle_time(int cpu);
 
-DECLARE_PER_CPU(struct s390_idle_data, s390_idle);
-
-cputime64_t s390_get_idle_time(int cpu);
-
-#define arch_idle_time(cpu) s390_get_idle_time(cpu)
+#define arch_idle_time(cpu) arch_cpu_idle_time(cpu)
 
 #endif /* _S390_CPUTIME_H */
diff --git a/arch/s390/include/asm/idle.h b/arch/s390/include/asm/idle.h
new file mode 100644
index 000000000000..6af037f574b8
--- /dev/null
+++ b/arch/s390/include/asm/idle.h
@@ -0,0 +1,26 @@
+/*
+ *  Copyright IBM Corp. 2014
+ *
+ *  Author: Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#ifndef _S390_IDLE_H
+#define _S390_IDLE_H
+
+#include <linux/types.h>
+#include <linux/device.h>
+
+struct s390_idle_data {
+        unsigned int sequence;
+        unsigned long long idle_count;
+        unsigned long long idle_time;
+        unsigned long long clock_idle_enter;
+        unsigned long long clock_idle_exit;
+        unsigned long long timer_idle_enter;
+        unsigned long long timer_idle_exit;
+};
+
+extern struct device_attribute dev_attr_idle_count;
+extern struct device_attribute dev_attr_idle_time_us;
+
+#endif /* _S390_IDLE_H */
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index bc796d73129b..3d0871058306 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -289,7 +289,12 @@ static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
         return (psw.addr - ilc) & mask;
 #endif
 }
- 
+
+/*
+ * Function to stop a processor until the next interrupt occurs
+ */
+void enabled_wait(void);
+
 /*
  * Function to drop a processor into disabled wait state
  */
diff --git a/arch/s390/include/asm/vtimer.h b/arch/s390/include/asm/vtimer.h
index bfe25d513ad2..10a179af62d8 100644
--- a/arch/s390/include/asm/vtimer.h
+++ b/arch/s390/include/asm/vtimer.h
@@ -28,6 +28,4 @@ extern int del_virt_timer(struct vtimer_list *timer);
 extern void init_cpu_vtimer(void);
 extern void vtime_init(void);
 
-extern void vtime_stop_cpu(void);
-
 #endif /* _ASM_S390_TIMER_H */
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index 3249e1f36d55..c249785669f3 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -28,7 +28,7 @@ CFLAGS_ptrace.o		+= -DUTS_MACHINE='"$(UTS_MACHINE)"'
 
 CFLAGS_sysinfo.o += -Iinclude/math-emu -Iarch/s390/math-emu -w
 
-obj-y   := traps.o time.o process.o base.o early.o setup.o vtime.o
+obj-y   := traps.o time.o process.o base.o early.o setup.o idle.o vtime.o
 obj-y   += processor.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o nmi.o
 obj-y   += debug.o irq.o ipl.o dis.o diag.o sclp.o vdso.o
 obj-y   += sysinfo.o jump_label.o lgr.o os_info.o machine_kexec.o pgm_check.o
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index 3e9e479d9b49..ef279a136801 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -9,7 +9,7 @@
 #include <linux/kbuild.h>
 #include <linux/kvm_host.h>
 #include <linux/sched.h>
-#include <asm/cputime.h>
+#include <asm/idle.h>
 #include <asm/vdso.h>
 #include <asm/pgtable.h>
 
diff --git a/arch/s390/kernel/entry.h b/arch/s390/kernel/entry.h
index 58541633b8d6..cd68869f9504 100644
--- a/arch/s390/kernel/entry.h
+++ b/arch/s390/kernel/entry.h
@@ -4,7 +4,7 @@
 #include <linux/types.h>
 #include <linux/signal.h>
 #include <asm/ptrace.h>
-#include <asm/cputime.h>
+#include <asm/idle.h>
 
 extern void *restart_stack;
 extern unsigned long suspend_zero_pages;
diff --git a/arch/s390/kernel/idle.c b/arch/s390/kernel/idle.c
new file mode 100644
index 000000000000..c846aee7372f
--- /dev/null
+++ b/arch/s390/kernel/idle.c
@@ -0,0 +1,124 @@
+/*
+ * Idle functions for s390.
+ *
+ * Copyright IBM Corp. 2014
+ *
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/kernel_stat.h>
+#include <linux/kprobes.h>
+#include <linux/notifier.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <asm/cputime.h>
+#include <asm/nmi.h>
+#include <asm/smp.h>
+#include "entry.h"
+
+static DEFINE_PER_CPU(struct s390_idle_data, s390_idle);
+
+void __kprobes enabled_wait(void)
+{
+        struct s390_idle_data *idle = &__get_cpu_var(s390_idle);
+        unsigned long long idle_time;
+        unsigned long psw_mask;
+
+        trace_hardirqs_on();
+
+        /* Wait for external, I/O or machine check interrupt. */
+        psw_mask = PSW_KERNEL_BITS | PSW_MASK_WAIT | PSW_MASK_DAT |
+                PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
+        clear_cpu_flag(CIF_NOHZ_DELAY);
+
+        /* Call the assembler magic in entry.S */
+        psw_idle(idle, psw_mask);
+
+        /* Account time spent with enabled wait psw loaded as idle time. */
+        idle->sequence++;
+        smp_wmb();
+        idle_time = idle->clock_idle_exit - idle->clock_idle_enter;
+        idle->clock_idle_enter = idle->clock_idle_exit = 0ULL;
+        idle->idle_time += idle_time;
+        idle->idle_count++;
+        account_idle_time(idle_time);