Re: [PATCH v2 00/44] cpuidle,rcu: Clean up the mess

Peter Zijlstra
2022-09-20T14:04:47Z

Because Nadav asked about tracing/kprobing idle, I had another go around
and noticed not all functions calling ct_cpuidle_enter are __cpuidle.

Basically all cpuidle_driver::enter functions should be __cpuidle; i'll
do that audit shortly.

For now this is ct_cpuidle_enter / CPU_IDLE_ENTER users.

---
--- a/arch/arm/mach-imx/cpuidle-imx6q.c
+++ b/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())
--- a/arch/arm/mach-imx/cpuidle-imx6sx.c
+++ b/arch/arm/mach-imx/cpuidle-imx6sx.c
@@ -30,8 +30,8 @@ static int imx6sx_idle_finish(unsigned l
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);

--- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
+++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
@@ -224,8 +224,8 @@ static void __init save_l2x0_context(voi
* 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;
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -175,7 +175,7 @@ static int omap34xx_do_sram_idle(unsigne
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*/
--- a/arch/arm64/kernel/cpuidle.c
+++ b/arch/arm64/kernel/cpuidle.c
@@ -62,7 +62,7 @@ int acpi_processor_ffh_lpi_probe(unsigne
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;

--- a/drivers/cpuidle/cpuidle-arm.c
+++ b/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
--- a/drivers/cpuidle/cpuidle-big_little.c
+++ b/drivers/cpuidle/cpuidle-big_little.c
@@ -122,8 +122,8 @@ static int notrace bl_powerdown_finisher
* 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();
--- a/drivers/cpuidle/cpuidle-mvebu-v7.c
+++ b/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;
--- a/drivers/cpuidle/cpuidle-psci.c
+++ b/drivers/cpuidle/cpuidle-psci.c
@@ -49,14 +49,9 @@ static inline u32 psci_get_domain_state(
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[] = {
--- a/drivers/cpuidle/cpuidle-qcom-spm.c
+++ b/drivers/cpuidle/cpuidle-qcom-spm.c
@@ -58,8 +58,8 @@ static int qcom_cpu_spc(struct spm_drive
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);
--- a/drivers/cpuidle/cpuidle-riscv-sbi.c
+++ b/drivers/cpuidle/cpuidle-riscv-sbi.c
@@ -93,17 +93,17 @@ 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);

return CPU_PM_CPU_IDLE_ENTER_PARAM(sbi_suspend, idx, states[idx]);
}

-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;
--- a/drivers/cpuidle/cpuidle-tegra.c
+++ b/drivers/cpuidle/cpuidle-tegra.c
@@ -160,8 +160,8 @@ static int tegra_cpuidle_coupled_barrier
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_in
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);
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -137,11 +137,13 @@ int cpuidle_find_deepest_state(struct cp
}

#ifdef CONFIG_SUSPEND
-static void enter_s2idle_proper(struct cpuidle_driver *drv,
- struct cpuidle_device *dev, int index)
+static __cpuidle void enter_s2idle_proper(struct cpuidle_driver *drv,
+ struct cpuidle_device *dev, int index)
{
- ktime_t time_start, time_end;
struct cpuidle_state *target_state = &drv->states[index];
+ ktime_t time_start, time_end;
+
+ instrumentation_begin();

time_start = ns_to_ktime(local_clock());

@@ -152,13 +154,18 @@ static void enter_s2idle_proper(struct c
* suspended is generally unsafe.
*/
stop_critical_timings();
- if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
+ if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE)) {
ct_cpuidle_enter();
+ /* Annotate away the indirect call */
+ instrumentation_begin();
+ }
target_state->enter_s2idle(dev, drv, index);
if (WARN_ON_ONCE(!irqs_disabled()))
raw_local_irq_disable();
- if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
+ if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE)) {
+ instrumentation_end();
ct_cpuidle_exit();
+ }
tick_unfreeze();
start_critical_timings();

@@ -166,6 +173,7 @@ static void enter_s2idle_proper(struct c

dev->states_usage[index].s2idle_time += ktime_us_delta(time_end, time_start);
dev->states_usage[index].s2idle_usage++;
+ instrumentation_end();
}

/**
@@ -200,8 +208,9 @@ int cpuidle_enter_s2idle(struct cpuidle_
* @drv: cpuidle driver for this cpu
* @index: index into the states table in @drv of the state to enter
*/
-int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
- int index)
+__cpuidle int cpuidle_enter_state(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
{
int entered_state;

@@ -209,6 +218,8 @@ int cpuidle_enter_state(struct cpuidle_d
bool broadcast = !!(target_state->flags & CPUIDLE_FLAG_TIMER_STOP);
ktime_t time_start, time_end;

+ instrumentation_begin();
+
/*
* Tell the time framework to switch to a broadcast timer because our
* local timer will be shut down. If a local timer is used from another
@@ -235,15 +246,21 @@ int cpuidle_enter_state(struct cpuidle_d
time_start = ns_to_ktime(local_clock());

stop_critical_timings();
- if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
+ if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE)) {
ct_cpuidle_enter();
+ /* Annotate away the indirect call */
+ instrumentation_begin();
+ }

entered_state = target_state->enter(dev, drv, index);
+
if (WARN_ONCE(!irqs_disabled(), "%ps leaked IRQ state", target_state->enter))
raw_local_irq_disable();

- if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE))
+ if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE)) {
+ instrumentation_end();
ct_cpuidle_exit();
+ }
start_critical_timings();

sched_clock_idle_wakeup_event();
@@ -306,6 +323,8 @@ int cpuidle_enter_state(struct cpuidle_d
dev->states_usage[index].rejected++;
}

+ instrumentation_end();
+
return entered_state;
}