ACPI: cpuidle: Support C1 idle time accounting
Show C1 idle time in /sysfs cpuidle interface. C1 idle time may not
be entirely accurate in all cases. It includes the time spent
in the interrupt handler after wakeup with "hlt" based C1. But, it will
be accurate with "mwait" based C1.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 4ba3a9a..fea7159 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -1407,8 +1407,10 @@
static int acpi_idle_enter_c1(struct cpuidle_device *dev,
struct cpuidle_state *state)
{
+ u32 t1, t2;
struct acpi_processor *pr;
struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
+
pr = processors[smp_processor_id()];
if (unlikely(!pr))
@@ -1418,12 +1420,14 @@
if (pr->flags.bm_check)
acpi_idle_update_bm_rld(pr, cx);
+ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
acpi_idle_do_entry(cx);
+ t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
local_irq_enable();
cx->usage++;
- return 0;
+ return ticks_elapsed_in_us(t1, t2);
}
/**
@@ -1660,6 +1664,7 @@
switch (cx->type) {
case ACPI_STATE_C1:
state->flags |= CPUIDLE_FLAG_SHALLOW;
+ state->flags |= CPUIDLE_FLAG_TIME_VALID;
state->enter = acpi_idle_enter_c1;
dev->safe_state = state;
break;
