ACPI, intel_idle: Cleanup idle= internal variables
Having four variables for the same thing:
idle_halt, idle_nomwait, force_mwait and boot_option_idle_overrides
is rather confusing and unnecessary complex.
if idle= boot param is passed, only set up one variable:
boot_option_idle_overrides
Introduces following functional changes/fixes:
- intel_idle driver does not register if any idle=xy
boot param is passed.
- processor_idle.c will also not register a cpuidle driver
and get active if idle=halt is passed.
Before a cpuidle driver with one (C1, halt) state got registered
Now the default_idle function will be used which finally uses
the same idle call to enter sleep state (safe_halt()), but
without registering a whole cpuidle driver.
That means idle= param will always avoid cpuidle drivers to register
with one exception (same behavior as before):
idle=nomwait
may still register acpi_idle cpuidle driver, but C1 will not use
mwait, but hlt. This can be a workaround for IO based deeper sleep
states where C1 mwait causes problems.
Signed-off-by: Thomas Renninger <trenn@suse.de>
cc: x86@kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index dcb38f8..eefd4aa 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -79,6 +79,13 @@
static unsigned int latency_factor __read_mostly = 2;
module_param(latency_factor, uint, 0644);
+static int disabled_by_idle_boot_param(void)
+{
+ return boot_option_idle_override == IDLE_POLL ||
+ boot_option_idle_override == IDLE_FORCE_MWAIT ||
+ boot_option_idle_override == IDLE_HALT;
+}
+
/*
* IBM ThinkPad R40e crashes mysteriously when going into C2 or C3.
* For now disable this. Probably a bug somewhere else.
@@ -455,7 +462,7 @@
continue;
}
if (cx.type == ACPI_STATE_C1 &&
- (idle_halt || idle_nomwait)) {
+ (boot_option_idle_override == IDLE_NOMWAIT)) {
/*
* In most cases the C1 space_id obtained from
* _CST object is FIXED_HARDWARE access mode.
@@ -1058,7 +1065,7 @@
{
int ret = 0;
- if (boot_option_idle_override)
+ if (disabled_by_idle_boot_param())
return 0;
if (!pr)
@@ -1089,19 +1096,10 @@
acpi_status status = 0;
static int first_run;
- if (boot_option_idle_override)
+ if (disabled_by_idle_boot_param())
return 0;
if (!first_run) {
- if (idle_halt) {
- /*
- * When the boot option of "idle=halt" is added, halt
- * is used for CPU IDLE.
- * In such case C2/C3 is meaningless. So the max_cstate
- * is set to one.
- */
- max_cstate = 1;
- }
dmi_check_system(processor_power_dmi_table);
max_cstate = acpi_processor_cstate_check(max_cstate);
if (max_cstate < ACPI_C_STATES_MAX)
@@ -1142,7 +1140,7 @@
int acpi_processor_power_exit(struct acpi_processor *pr,
struct acpi_device *device)
{
- if (boot_option_idle_override)
+ if (disabled_by_idle_boot_param())
return 0;
cpuidle_unregister_device(&pr->power.dev);