cpuidle, arch: Mark all ct_cpuidle_enter() callers __cpuidle

For all cpuidle drivers that use CPUIDLE_FLAG_RCU_IDLE, ensure that
all functions that call ct_cpuidle_enter() are marked __cpuidle.

( due to lack of noinstr validation on these platforms it is entirely
  possible this isn't complete )

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230112195542.274096325@infradead.org

arch/arm/mach-imx/cpuidle-imx6q.c

@@ -17,8 +17,8 @@
 static int num_idle_cpus = 0;
 static DEFINE_RAW_SPINLOCK(cpuidle_lock);
 
-static int imx6q_enter_wait(struct cpuidle_device *dev,
-			    struct cpuidle_driver *drv, int index)
+static __cpuidle int imx6q_enter_wait(struct cpuidle_device *dev,
+				      struct cpuidle_driver *drv, int index)
 {
 	raw_spin_lock(&cpuidle_lock);
 	if (++num_idle_cpus == num_online_cpus())

arch/arm/mach-imx/cpuidle-imx6sx.c

@@ -30,8 +30,8 @@ static int imx6sx_idle_finish(unsigned long val)
 	return 0;
 }
 
-static int imx6sx_enter_wait(struct cpuidle_device *dev,
-			    struct cpuidle_driver *drv, int index)
+static __cpuidle int imx6sx_enter_wait(struct cpuidle_device *dev,
+				       struct cpuidle_driver *drv, int index)
 {
 	imx6_set_lpm(WAIT_UNCLOCKED);
 

arch/arm/mach-omap2/omap-mpuss-lowpower.c

@@ -224,8 +224,8 @@ static void __init save_l2x0_context(void)
  *	2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
  *	3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF
  */
-int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state,
-			 bool rcuidle)
+__cpuidle int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state,
+				   bool rcuidle)
 {
 	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
 	unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET;

arch/arm/mach-omap2/pm34xx.c

@@ -175,7 +175,7 @@ static int omap34xx_do_sram_idle(unsigned long save_state)
 	return 0;
 }
 
-void omap_sram_idle(bool rcuidle)
+__cpuidle void omap_sram_idle(bool rcuidle)
 {
 	/* Variable to tell what needs to be saved and restored
 	 * in omap_sram_idle*/

arch/arm64/kernel/cpuidle.c

@@ -62,7 +62,7 @@ int acpi_processor_ffh_lpi_probe(unsigned int cpu)
 	return psci_acpi_cpu_init_idle(cpu);
 }
 
-int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi)
+__cpuidle int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi)
 {
 	u32 state = lpi->address;
 

drivers/cpuidle/cpuidle-arm.c

@@ -31,8 +31,8 @@
  * Called from the CPUidle framework to program the device to the
  * specified target state selected by the governor.
  */
-static int arm_enter_idle_state(struct cpuidle_device *dev,
-				struct cpuidle_driver *drv, int idx)
+static __cpuidle int arm_enter_idle_state(struct cpuidle_device *dev,
+					  struct cpuidle_driver *drv, int idx)
 {
 	/*
 	 * Pass idle state index to arm_cpuidle_suspend which in turn

drivers/cpuidle/cpuidle-big_little.c

@@ -122,8 +122,8 @@ static int notrace bl_powerdown_finisher(unsigned long arg)
  * Called from the CPUidle framework to program the device to the
  * specified target state selected by the governor.
  */
-static int bl_enter_powerdown(struct cpuidle_device *dev,
-				struct cpuidle_driver *drv, int idx)
+static __cpuidle int bl_enter_powerdown(struct cpuidle_device *dev,
+					struct cpuidle_driver *drv, int idx)
 {
 	cpu_pm_enter();
 	ct_cpuidle_enter();

drivers/cpuidle/cpuidle-mvebu-v7.c

@@ -25,9 +25,9 @@
 
 static int (*mvebu_v7_cpu_suspend)(int);
 
-static int mvebu_v7_enter_idle(struct cpuidle_device *dev,
-				struct cpuidle_driver *drv,
-				int index)
+static __cpuidle int mvebu_v7_enter_idle(struct cpuidle_device *dev,
+					 struct cpuidle_driver *drv,
+					 int index)
 {
 	int ret;
 	bool deepidle = false;

drivers/cpuidle/cpuidle-psci.c

@@ -49,14 +49,9 @@ static inline u32 psci_get_domain_state(void)
 	return __this_cpu_read(domain_state);
 }
 
-static inline int psci_enter_state(int idx, u32 state)
-{
-	return CPU_PM_CPU_IDLE_ENTER_PARAM(psci_cpu_suspend_enter, idx, state);
-}
-
-static int __psci_enter_domain_idle_state(struct cpuidle_device *dev,
-					  struct cpuidle_driver *drv, int idx,
-					  bool s2idle)
+static __cpuidle int __psci_enter_domain_idle_state(struct cpuidle_device *dev,
+						    struct cpuidle_driver *drv, int idx,
+						    bool s2idle)
 {
 	struct psci_cpuidle_data *data = this_cpu_ptr(&psci_cpuidle_data);
 	u32 *states = data->psci_states;
@@ -192,12 +187,12 @@ static void psci_idle_init_cpuhp(void)
 		pr_warn("Failed %d while setup cpuhp state\n", err);
 }
 
-static int psci_enter_idle_state(struct cpuidle_device *dev,
-				struct cpuidle_driver *drv, int idx)
+static __cpuidle int psci_enter_idle_state(struct cpuidle_device *dev,
+					   struct cpuidle_driver *drv, int idx)
 {
 	u32 *state = __this_cpu_read(psci_cpuidle_data.psci_states);
 
-	return psci_enter_state(idx, state[idx]);
+	return CPU_PM_CPU_IDLE_ENTER_PARAM(psci_cpu_suspend_enter, idx, state[idx]);
 }
 
 static const struct of_device_id psci_idle_state_match[] = {

drivers/cpuidle/cpuidle-qcom-spm.c

@@ -58,8 +58,8 @@ static int qcom_cpu_spc(struct spm_driver_data *drv)
 	return ret;
 }
 
-static int spm_enter_idle_state(struct cpuidle_device *dev,
-				struct cpuidle_driver *drv, int idx)
+static __cpuidle int spm_enter_idle_state(struct cpuidle_device *dev,
+					  struct cpuidle_driver *drv, int idx)
 {
 	struct cpuidle_qcom_spm_data *data = container_of(drv, struct cpuidle_qcom_spm_data,
 							  cpuidle_driver);

drivers/cpuidle/cpuidle-riscv-sbi.c

@@ -93,8 +93,8 @@ static int sbi_suspend(u32 state)
 		return sbi_suspend_finisher(state, 0, 0);
 }
 
-static int sbi_cpuidle_enter_state(struct cpuidle_device *dev,
-				   struct cpuidle_driver *drv, int idx)
+static __cpuidle int sbi_cpuidle_enter_state(struct cpuidle_device *dev,
+					     struct cpuidle_driver *drv, int idx)
 {
 	u32 *states = __this_cpu_read(sbi_cpuidle_data.states);
 	u32 state = states[idx];
@@ -106,9 +106,9 @@ static int sbi_cpuidle_enter_state(struct cpuidle_device *dev,
 							     idx, state);
 }
 
-static int __sbi_enter_domain_idle_state(struct cpuidle_device *dev,
-					  struct cpuidle_driver *drv, int idx,
-					  bool s2idle)
+static __cpuidle int __sbi_enter_domain_idle_state(struct cpuidle_device *dev,
+						   struct cpuidle_driver *drv, int idx,
+						   bool s2idle)
 {
 	struct sbi_cpuidle_data *data = this_cpu_ptr(&sbi_cpuidle_data);
 	u32 *states = data->states;

drivers/cpuidle/cpuidle-tegra.c

@@ -160,8 +160,8 @@ static int tegra_cpuidle_coupled_barrier(struct cpuidle_device *dev)
 	return 0;
 }
 
-static int tegra_cpuidle_state_enter(struct cpuidle_device *dev,
-				     int index, unsigned int cpu)
+static __cpuidle int tegra_cpuidle_state_enter(struct cpuidle_device *dev,
+					       int index, unsigned int cpu)
 {
 	int err;
 
@@ -226,9 +226,9 @@ static int tegra_cpuidle_adjust_state_index(int index, unsigned int cpu)
 	return index;
 }
 
-static int tegra_cpuidle_enter(struct cpuidle_device *dev,
-			       struct cpuidle_driver *drv,
-			       int index)
+static __cpuidle int tegra_cpuidle_enter(struct cpuidle_device *dev,
+					 struct cpuidle_driver *drv,
+					 int index)
 {
 	bool do_rcu = drv->states[index].flags & CPUIDLE_FLAG_RCU_IDLE;
 	unsigned int cpu = cpu_logical_map(dev->cpu);