ACPI: Eliminate us to pm ticks conversion in common path

acpi_enter_[simple|bm] routines does us to pm tick conversion on every
idle wakeup and the value is only used in /proc/acpi display. We can
store the time in us and convert it into pm ticks before printing instead and
avoid the conversion in the common path.

Signed-off-by: Venkatesh Pallipadi <venki@google.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 5 insertions, 10 deletions

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 6b38a6b43ce8..b1b385692f46 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -80,7 +80,7 @@ module_param(nocst, uint, 0000);
 static unsigned int latency_factor __read_mostly = 2;
 module_param(latency_factor, uint, 0644);
 
-static s64 us_to_pm_timer_ticks(s64 t)
+static u64 us_to_pm_timer_ticks(s64 t)
 {
         return div64_u64(t * PM_TIMER_FREQUENCY, 1000000);
 }
@@ -731,10 +731,10 @@ static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset)
 
                 seq_puts(seq, "demotion[--] ");
 
-                seq_printf(seq, "latency[%03d] usage[%08d] duration[%020llu]\n",
+                seq_printf(seq, "latency[%03d] usage[%08d] duration[%020Lu]\n",
                            pr->power.states[i].latency,
                            pr->power.states[i].usage,
-                           (unsigned long long)pr->power.states[i].time);
+                           us_to_pm_timer_ticks(pr->power.states[i].time));
         }
 
       end:
@@ -861,7 +861,6 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
         ktime_t  kt1, kt2;
         s64 idle_time_ns;
         s64 idle_time;
-        s64 sleep_ticks = 0;
 
         pr = __get_cpu_var(processors);
 
@@ -906,8 +905,6 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
         idle_time = idle_time_ns;
         do_div(idle_time, NSEC_PER_USEC);
 
-        sleep_ticks = us_to_pm_timer_ticks(idle_time);
-
         /* Tell the scheduler how much we idled: */
         sched_clock_idle_wakeup_event(idle_time_ns);
 
@@ -918,7 +915,7 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
         cx->usage++;
 
         lapic_timer_state_broadcast(pr, cx, 0);
-        cx->time += sleep_ticks;
+        cx->time += idle_time;
         return idle_time;
 }
 
@@ -940,7 +937,6 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
         ktime_t  kt1, kt2;
         s64 idle_time_ns;
         s64 idle_time;
-        s64 sleep_ticks = 0;
 
 
         pr = __get_cpu_var(processors);
@@ -1026,7 +1022,6 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
         idle_time = idle_time_ns;
         do_div(idle_time, NSEC_PER_USEC);
 
-        sleep_ticks = us_to_pm_timer_ticks(idle_time);
         /* Tell the scheduler how much we idled: */
         sched_clock_idle_wakeup_event(idle_time_ns);
 
@@ -1037,7 +1032,7 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
         cx->usage++;
 
         lapic_timer_state_broadcast(pr, cx, 0);
-        cx->time += sleep_ticks;
+        cx->time += idle_time;
         return idle_time;
 }