[PATCH 2/8] intel_idle: Fold intel_idle_probe() into intel_idle_init()

From: Rafael J. Wysocki
Date: Fri Jan 10 2020 - 05:58:22 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

There is no particular reason why intel_idle_probe() needs to be
a separate function and folding it into intel_idle_init() causes
the code to be somewhat easier to follow, so do just that.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/idle/intel_idle.c | 97 +++++++++++++++++++---------------------------
1 file changed, 42 insertions(+), 55 deletions(-)

Index: linux-pm/drivers/idle/intel_idle.c
===================================================================
--- linux-pm.orig/drivers/idle/intel_idle.c
+++ linux-pm/drivers/idle/intel_idle.c
@@ -1297,58 +1297,6 @@ static inline bool intel_idle_off_by_def
#endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */

/*
- * intel_idle_probe()
- */
-static int __init intel_idle_probe(void)
-{
- unsigned int eax, ebx, ecx;
- const struct x86_cpu_id *id;
-
- if (max_cstate == 0) {
- pr_debug("disabled\n");
- return -EPERM;
- }
-
- id = x86_match_cpu(intel_idle_ids);
- if (id) {
- if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
- pr_debug("Please enable MWAIT in BIOS SETUP\n");
- return -ENODEV;
- }
- } else {
- id = x86_match_cpu(intel_mwait_ids);
- if (!id)
- return -ENODEV;
- }
-
- if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
- return -ENODEV;
-
- cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates);
-
- if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
- !(ecx & CPUID5_ECX_INTERRUPT_BREAK) ||
- !mwait_substates)
- return -ENODEV;
-
- pr_debug("MWAIT substates: 0x%x\n", mwait_substates);
-
- icpu = (const struct idle_cpu *)id->driver_data;
- if (icpu) {
- cpuidle_state_table = icpu->state_table;
- if (icpu->use_acpi)
- intel_idle_acpi_cst_extract();
- } else if (!intel_idle_acpi_cst_extract()) {
- return -ENODEV;
- }
-
- pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n",
- boot_cpu_data.x86_model);
-
- return 0;
-}
-
-/*
* intel_idle_cpuidle_devices_uninit()
* Unregisters the cpuidle devices.
*/
@@ -1632,15 +1580,54 @@ static int intel_idle_cpu_online(unsigne

static int __init intel_idle_init(void)
{
+ const struct x86_cpu_id *id;
+ unsigned int eax, ebx, ecx;
int retval;

/* Do not load intel_idle at all for now if idle= is passed */
if (boot_option_idle_override != IDLE_NO_OVERRIDE)
return -ENODEV;

- retval = intel_idle_probe();
- if (retval)
- return retval;
+ if (max_cstate == 0) {
+ pr_debug("disabled\n");
+ return -EPERM;
+ }
+
+ id = x86_match_cpu(intel_idle_ids);
+ if (id) {
+ if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
+ pr_debug("Please enable MWAIT in BIOS SETUP\n");
+ return -ENODEV;
+ }
+ } else {
+ id = x86_match_cpu(intel_mwait_ids);
+ if (!id)
+ return -ENODEV;
+ }
+
+ if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
+ return -ENODEV;
+
+ cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates);
+
+ if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
+ !(ecx & CPUID5_ECX_INTERRUPT_BREAK) ||
+ !mwait_substates)
+ return -ENODEV;
+
+ pr_debug("MWAIT substates: 0x%x\n", mwait_substates);
+
+ icpu = (const struct idle_cpu *)id->driver_data;
+ if (icpu) {
+ cpuidle_state_table = icpu->state_table;
+ if (icpu->use_acpi)
+ intel_idle_acpi_cst_extract();
+ } else if (!intel_idle_acpi_cst_extract()) {
+ return -ENODEV;
+ }
+
+ pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n",
+ boot_cpu_data.x86_model);

intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
if (intel_idle_cpuidle_devices == NULL)