1 files changed, 3 insertions, 61 deletions

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 1e06436f07c2..b6110bdf8dc2 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -46,7 +46,6 @@
 #include <asm/processor.h>
 #include <asm/irq.h>
 #include <asm/timer.h>
-#include <asm/cpu.h>
 #include "entry.h"
 
 asmlinkage void ret_from_fork(void) asm ("ret_from_fork");
@@ -76,35 +75,12 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
         return sf->gprs[8];
 }
 
-DEFINE_PER_CPU(struct s390_idle_data, s390_idle) = {
-        .lock = __SPIN_LOCK_UNLOCKED(s390_idle.lock)
-};
-
-void s390_idle_leave(void)
-{
-        struct s390_idle_data *idle;
-        unsigned long long idle_time;
-
-        idle = &__get_cpu_var(s390_idle);
-        idle_time = S390_lowcore.int_clock - idle->idle_enter;
-        spin_lock(&idle->lock);
-        idle->idle_time += idle_time;
-        idle->idle_enter = 0ULL;
-        idle->idle_count++;
-        spin_unlock(&idle->lock);
-        vtime_start_cpu_timer();
-}
-
 extern void s390_handle_mcck(void);
 /*
  * The idle loop on a S390...
  */
 static void default_idle(void)
 {
-        struct s390_idle_data *idle = &__get_cpu_var(s390_idle);
-        unsigned long addr;
-        psw_t psw;
-
         /* CPU is going idle. */
         local_irq_disable();
         if (need_resched()) {
@@ -120,7 +96,6 @@ static void default_idle(void)
         local_mcck_disable();
         if (test_thread_flag(TIF_MCCK_PENDING)) {
                 local_mcck_enable();
-                s390_idle_leave();
                 local_irq_enable();
                 s390_handle_mcck();
                 return;
@@ -128,42 +103,9 @@ static void default_idle(void)
         trace_hardirqs_on();
         /* Don't trace preempt off for idle. */
         stop_critical_timings();
-        vtime_stop_cpu_timer();
-
-        /*
-         * The inline assembly is equivalent to
-         *      idle->idle_enter = get_clock();
-         *      __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT |
-         *                         PSW_MASK_IO | PSW_MASK_EXT);
-         * The difference is that the inline assembly makes sure that
-         * the stck instruction is right before the lpsw instruction.
-         * This is done to increase the precision.
-         */
-
-        /* Wait for external, I/O or machine check interrupt. */
-        psw.mask = psw_kernel_bits|PSW_MASK_WAIT|PSW_MASK_IO|PSW_MASK_EXT;
-#ifndef __s390x__
-        asm volatile(
-                "       basr    %0,0\n"
-                "0:     ahi     %0,1f-0b\n"
-                "       st      %0,4(%2)\n"
-                "       stck    0(%3)\n"
-                "       lpsw    0(%2)\n"
-                "1:"
-                : "=&d" (addr), "=m" (idle->idle_enter)
-                : "a" (&psw), "a" (&idle->idle_enter), "m" (psw)
-                : "memory", "cc");
-#else /* __s390x__ */
-        asm volatile(
-                "       larl    %0,1f\n"
-                "       stg     %0,8(%2)\n"
-                "       stck    0(%3)\n"
-                "       lpswe   0(%2)\n"
-                "1:"
-                : "=&d" (addr), "=m" (idle->idle_enter)
-                : "a" (&psw), "a" (&idle->idle_enter), "m" (psw)
-                : "memory", "cc");
-#endif /* __s390x__ */
+        /* Stop virtual timer and halt the cpu. */
+        vtime_stop_cpu();
+        /* Reenable preemption tracer. */
         start_critical_timings();
 }