2 files changed, 24 insertions, 29 deletions

diff --git a/arch/i386/kernel/vmi.c b/arch/i386/kernel/vmi.c
index bb5a7abf949c..8417f741fac8 100644
--- a/arch/i386/kernel/vmi.c
+++ b/arch/i386/kernel/vmi.c
@@ -54,6 +54,7 @@ static int disable_pse;
 static int disable_sep;
 static int disable_tsc;
 static int disable_mtrr;
+static int disable_noidle;
 
 /* Cached VMI operations */
 struct {
@@ -255,7 +256,6 @@ static void vmi_nop(void)
 }
 
 /* For NO_IDLE_HZ, we stop the clock when halting the kernel */
-#ifdef CONFIG_NO_IDLE_HZ
 static fastcall void vmi_safe_halt(void)
 {
         int idle = vmi_stop_hz_timer();
@@ -266,7 +266,6 @@ static fastcall void vmi_safe_halt(void)
                 local_irq_enable();
         }
 }
-#endif
 
 #ifdef CONFIG_DEBUG_PAGE_TYPE
 
@@ -742,12 +741,7 @@ static inline int __init activate_vmi(void)
                      (char *)paravirt_ops.save_fl);
         patch_offset(&irq_save_disable_callout[IRQ_PATCH_DISABLE],
                      (char *)paravirt_ops.irq_disable);
-#ifndef CONFIG_NO_IDLE_HZ
-        para_fill(safe_halt, Halt);
-#else
-        vmi_ops.halt = vmi_get_function(VMI_CALL_Halt);
-        paravirt_ops.safe_halt = vmi_safe_halt;
-#endif
+
         para_fill(wbinvd, WBINVD);
         /* paravirt_ops.read_msr = vmi_rdmsr */
         /* paravirt_ops.write_msr = vmi_wrmsr */
@@ -881,6 +875,12 @@ static inline int __init activate_vmi(void)
 #endif
                 custom_sched_clock = vmi_sched_clock;
         }
+        if (!disable_noidle)
+                para_fill(safe_halt, Halt);
+        else {
+                vmi_ops.halt = vmi_get_function(VMI_CALL_Halt);
+                paravirt_ops.safe_halt = vmi_safe_halt;
+        }
 
         /*
          * Alternative instruction rewriting doesn't happen soon enough
@@ -914,9 +914,11 @@ void __init vmi_init(void)
 
         local_irq_save(flags);
         activate_vmi();
-#ifdef CONFIG_SMP
+
+#ifdef CONFIG_X86_IO_APIC
         no_timer_check = 1;
 #endif
+
         local_irq_restore(flags & X86_EFLAGS_IF);
 }
 
@@ -942,7 +944,8 @@ static int __init parse_vmi(char *arg)
         } else if (!strcmp(arg, "disable_mtrr")) {
                 clear_bit(X86_FEATURE_MTRR, boot_cpu_data.x86_capability);
                 disable_mtrr = 1;
-        }
+        } else if (!strcmp(arg, "disable_noidle"))
+                disable_noidle = 1;
         return 0;
 }
 
diff --git a/arch/i386/kernel/vmitime.c b/arch/i386/kernel/vmitime.c
index 76d2adcae5a3..694aa85d22c2 100644
--- a/arch/i386/kernel/vmitime.c
+++ b/arch/i386/kernel/vmitime.c
@@ -276,16 +276,13 @@ static void vmi_account_real_cycles(unsigned long long cur_real_cycles)
 
         cycles_not_accounted = cur_real_cycles - real_cycles_accounted_system;
         while (cycles_not_accounted >= cycles_per_jiffy) {
-                /* systems wide jiffies and wallclock. */
+                /* systems wide jiffies. */
                 do_timer(1);
 
                 cycles_not_accounted -= cycles_per_jiffy;
                 real_cycles_accounted_system += cycles_per_jiffy;
         }
 
-        if (vmi_timer_ops.wallclock_updated())
-                update_xtime_from_wallclock();
-
         write_sequnlock(&xtime_lock);
 }
 
@@ -380,7 +377,6 @@ int vmi_stop_hz_timer(void)
         unsigned long seq, next;
         unsigned long long real_cycles_expiry;
         int cpu = smp_processor_id();
-        int idle;
 
         BUG_ON(!irqs_disabled());
         if (sysctl_hz_timer != 0)
@@ -388,13 +384,13 @@ int vmi_stop_hz_timer(void)
 
         cpu_set(cpu, nohz_cpu_mask);
         smp_mb();
+
         if (rcu_needs_cpu(cpu) || local_softirq_pending() ||
-            (next = next_timer_interrupt(), time_before_eq(next, jiffies))) {
+            (next = next_timer_interrupt(),
+             time_before_eq(next, jiffies + HZ/CONFIG_VMI_ALARM_HZ))) {
                 cpu_clear(cpu, nohz_cpu_mask);
-                next = jiffies;
-                idle = 0;
-        } else
-                idle = 1;
+                return 0;
+        }
 
         /* Convert jiffies to the real cycle counter. */
         do {
@@ -404,17 +400,13 @@ int vmi_stop_hz_timer(void)
         } while (read_seqretry(&xtime_lock, seq));
 
         /* This cpu is going idle. Disable the periodic alarm. */
-        if (idle) {
-                vmi_timer_ops.cancel_alarm(VMI_CYCLES_AVAILABLE);
-                per_cpu(idle_start_jiffies, cpu) = jiffies;
-        }
-
+        vmi_timer_ops.cancel_alarm(VMI_CYCLES_AVAILABLE);
+        per_cpu(idle_start_jiffies, cpu) = jiffies;
         /* Set the real time alarm to expire at the next event. */
         vmi_timer_ops.set_alarm(
-                      VMI_ALARM_WIRING | VMI_ALARM_IS_ONESHOT | VMI_CYCLES_REAL,
-                      real_cycles_expiry, 0);
-
-        return idle;
+                VMI_ALARM_WIRING | VMI_ALARM_IS_ONESHOT | VMI_CYCLES_REAL,
+                real_cycles_expiry, 0);
+        return 1;
 }
 
 static void vmi_reenable_hz_timer(int cpu)