POWERPC: pseries: cpuidle: use time keeping flag

The current code computes the idle time but that can be handled
by the cpuidle framework if we enable the .en_core_tk_irqen flag.

Set the flag and remove the code related to the time computation.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/arch/powerpc/platforms/pseries/processor_idle.c b/arch/powerpc/platforms/pseries/processor_idle.c
index 4d806b4..a197120 100644 (file)
--- a/arch/powerpc/platforms/pseries/processor_idle.c
+++ b/arch/powerpc/platforms/pseries/processor_idle.c
@@ -23,8 +23,9 @@
 #include "pseries.h"
 
 struct cpuidle_driver pseries_idle_driver = {
-       .name =         "pseries_idle",
-       .owner =        THIS_MODULE,
+       .name             = "pseries_idle",
+       .owner            = THIS_MODULE,
+       .en_core_tk_irqen = 1,
 };
 
 #define MAX_IDLE_STATE_COUNT   2
@@ -33,10 +34,8 @@ static int max_idle_state = MAX_IDLE_STATE_COUNT - 1;
 static struct cpuidle_device __percpu *pseries_cpuidle_devices;
 static struct cpuidle_state *cpuidle_state_table;
 
-static inline void idle_loop_prolog(unsigned long *in_purr, ktime_t *kt_before)
+static inline void idle_loop_prolog(unsigned long *in_purr)
 {
-
-       *kt_before = ktime_get();
        *in_purr = mfspr(SPRN_PURR);
        /*
         * Indicate to the HV that we are idle. Now would be
@@ -45,12 +44,10 @@ static inline void idle_loop_prolog(unsigned long *in_purr, ktime_t *kt_before)
        get_lppaca()->idle = 1;
 }
 
-static inline  s64 idle_loop_epilog(unsigned long in_purr, ktime_t kt_before)
+static inline void idle_loop_epilog(unsigned long in_purr)
 {
        get_lppaca()->wait_state_cycles += mfspr(SPRN_PURR) - in_purr;
        get_lppaca()->idle = 0;
-
-       return ktime_to_us(ktime_sub(ktime_get(), kt_before));
 }
 
 static int snooze_loop(struct cpuidle_device *dev,
@@ -58,10 +55,9 @@ static int snooze_loop(struct cpuidle_device *dev,
                        int index)
 {
        unsigned long in_purr;
-       ktime_t kt_before;
        int cpu = dev->cpu;
 
-       idle_loop_prolog(&in_purr, &kt_before);
+       idle_loop_prolog(&in_purr);
        local_irq_enable();
        set_thread_flag(TIF_POLLING_NRFLAG);
 
@@ -75,8 +71,8 @@ static int snooze_loop(struct cpuidle_device *dev,
        clear_thread_flag(TIF_POLLING_NRFLAG);
        smp_mb();
 
-       dev->last_residency =
-               (int)idle_loop_epilog(in_purr, kt_before);
+       idle_loop_epilog(in_purr);
+
        return index;
 }
 
@@ -102,9 +98,8 @@ static int dedicated_cede_loop(struct cpuidle_device *dev,
                                int index)
 {
        unsigned long in_purr;
-       ktime_t kt_before;
 
-       idle_loop_prolog(&in_purr, &kt_before);
+       idle_loop_prolog(&in_purr);
        get_lppaca()->donate_dedicated_cpu = 1;
 
        ppc64_runlatch_off();
@@ -112,8 +107,9 @@ static int dedicated_cede_loop(struct cpuidle_device *dev,
        check_and_cede_processor();
 
        get_lppaca()->donate_dedicated_cpu = 0;
-       dev->last_residency =
-               (int)idle_loop_epilog(in_purr, kt_before);
+
+       idle_loop_epilog(in_purr);
+
        return index;
 }
 
@@ -122,9 +118,8 @@ static int shared_cede_loop(struct cpuidle_device *dev,
                        int index)
 {
        unsigned long in_purr;
-       ktime_t kt_before;
 
-       idle_loop_prolog(&in_purr, &kt_before);
+       idle_loop_prolog(&in_purr);
 
        /*
         * Yield the processor to the hypervisor.  We return if
@@ -135,8 +130,8 @@ static int shared_cede_loop(struct cpuidle_device *dev,
         */
        check_and_cede_processor();
 
-       dev->last_residency =
-               (int)idle_loop_epilog(in_purr, kt_before);
+       idle_loop_epilog(in_purr);
+
        return index;
 }