1 files changed, 47 insertions, 37 deletions

diff --git a/arch/ppc64/kernel/iSeries_setup.c b/arch/ppc64/kernel/iSeries_setup.c
index fae215ea54b4..b4c919e18fa7 100644
--- a/arch/ppc64/kernel/iSeries_setup.c
+++ b/arch/ppc64/kernel/iSeries_setup.c
@@ -834,9 +834,6 @@ static int __init iSeries_src_init(void)
 
 late_initcall(iSeries_src_init);
 
-static unsigned long maxYieldTime = 0;
-static unsigned long minYieldTime = 0xffffffffffffffffUL;
-
 static inline void process_iSeries_events(void)
 {
         asm volatile ("li 0,0x5555; sc" : : : "r0", "r3");
@@ -845,7 +842,6 @@ static inline void process_iSeries_events(void)
 static void yield_shared_processor(void)
 {
         unsigned long tb;
-        unsigned long yieldTime;
 
         HvCall_setEnabledInterrupts(HvCall_MaskIPI |
                                     HvCall_MaskLpEvent |
@@ -856,13 +852,6 @@ static void yield_shared_processor(void)
         /* Compute future tb value when yield should expire */
         HvCall_yieldProcessor(HvCall_YieldTimed, tb+tb_ticks_per_jiffy);
 
-        yieldTime = get_tb() - tb;
-        if (yieldTime > maxYieldTime)
-                maxYieldTime = yieldTime;
-
-        if (yieldTime < minYieldTime)
-                minYieldTime = yieldTime;
-
         /*
          * The decrementer stops during the yield.  Force a fake decrementer
          * here and let the timer_interrupt code sort out the actual time.
@@ -871,45 +860,62 @@ static void yield_shared_processor(void)
         process_iSeries_events();
 }
 
-static int iSeries_idle(void)
+static int iseries_shared_idle(void)
 {
-        struct paca_struct *lpaca;
-        long oldval;
+        while (1) {
+                while (!need_resched() && !hvlpevent_is_pending()) {
+                        local_irq_disable();
+                        ppc64_runlatch_off();
+
+                        /* Recheck with irqs off */
+                        if (!need_resched() && !hvlpevent_is_pending())
+                                yield_shared_processor();
 
-        /* ensure iSeries run light will be out when idle */
-        ppc64_runlatch_off();
+                        HMT_medium();
+                        local_irq_enable();
+                }
+
+                ppc64_runlatch_on();
 
-        lpaca = get_paca();
+                if (hvlpevent_is_pending())
+                        process_iSeries_events();
+
+                schedule();
+        }
+
+        return 0;
+}
+
+static int iseries_dedicated_idle(void)
+{
+        struct paca_struct *lpaca = get_paca();
+        long oldval;
 
         while (1) {
-                if (lpaca->lppaca.shared_proc) {
-                        if (hvlpevent_is_pending())
-                                process_iSeries_events();
-                        if (!need_resched())
-                                yield_shared_processor();
-                } else {
-                        oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
+                oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
 
-                        if (!oldval) {
-                                set_thread_flag(TIF_POLLING_NRFLAG);
+                if (!oldval) {
+                        set_thread_flag(TIF_POLLING_NRFLAG);
 
-                                while (!need_resched()) {
+                        while (!need_resched()) {
+                                ppc64_runlatch_off();
+                                HMT_low();
+
+                                if (hvlpevent_is_pending()) {
                                         HMT_medium();
-                                        if (hvlpevent_is_pending())
-                                                process_iSeries_events();
-                                        HMT_low();
+                                        ppc64_runlatch_on();
+                                        process_iSeries_events();
                                 }
-
-                                HMT_medium();
-                                clear_thread_flag(TIF_POLLING_NRFLAG);
-                        } else {
-                                set_need_resched();
                         }
+
+                        HMT_medium();
+                        clear_thread_flag(TIF_POLLING_NRFLAG);
+                } else {
+                        set_need_resched();
                 }
 
                 ppc64_runlatch_on();
                 schedule();
-                ppc64_runlatch_off();
         }
 
         return 0;
@@ -940,6 +946,10 @@ void __init iSeries_early_setup(void)
         ppc_md.get_rtc_time = iSeries_get_rtc_time;
         ppc_md.calibrate_decr = iSeries_calibrate_decr;
         ppc_md.progress = iSeries_progress;
-        ppc_md.idle_loop = iSeries_idle;
+
+        if (get_paca()->lppaca.shared_proc)
+                ppc_md.idle_loop = iseries_shared_idle;
+        else
+                ppc_md.idle_loop = iseries_dedicated_idle;
 }