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intel_idle: refactor state->enter manipulation into its own function

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Since the 6.4 kernel, the logic for updating a state's enter method
based on "environmental conditions" (command line options, cpu sidechannel
workarounds etc etc) has gotten pretty complex.
This patch refactors this into a seperate small, self contained function
(no behavior changes) for improved readability and to make future
changes to this logic easier to do and understand.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Arjan van de Ven 2023-06-05 15:47:13 +00:00 committed by Rafael J. Wysocki
parent 858fd168a9
commit 4622ba923e
1 changed files with 28 additions and 22 deletions
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50
drivers/idle/intel_idle.c
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@ -1839,6 +1839,32 @@ static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
return true;
}
static void state_update_enter_method(struct cpuidle_state *state, int cstate)
{
if (state->flags & CPUIDLE_FLAG_INIT_XSTATE) {
/*
* Combining with XSTATE with IBRS or IRQ_ENABLE flags
* is not currently supported but this driver.
*/
WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IBRS);
WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IRQ_ENABLE);
state->enter = intel_idle_xstate;
} else if (cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS) &&
state->flags & CPUIDLE_FLAG_IBRS) {
/*
* IBRS mitigation requires that C-states are entered
* with interrupts disabled.
*/
WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IRQ_ENABLE);
state->enter = intel_idle_ibrs;
} else if (state->flags & CPUIDLE_FLAG_IRQ_ENABLE) {
state->enter = intel_idle_irq;
} else if (force_irq_on) {
pr_info("forced intel_idle_irq for state %d\n", cstate);
state->enter = intel_idle_irq;
}
}
static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
{
int cstate;
@ -1894,28 +1920,8 @@ static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
drv->states[drv->state_count] = cpuidle_state_table[cstate];
state = &drv->states[drv->state_count];
if (state->flags & CPUIDLE_FLAG_INIT_XSTATE) {
/*
* Combining with XSTATE with IBRS or IRQ_ENABLE flags
* is not currently supported but this driver.
*/
WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IBRS);
WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IRQ_ENABLE);
state->enter = intel_idle_xstate;
} else if (cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS) &&
state->flags & CPUIDLE_FLAG_IBRS) {
/*
* IBRS mitigation requires that C-states are entered
* with interrupts disabled.
*/
WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IRQ_ENABLE);
state->enter = intel_idle_ibrs;
} else if (state->flags & CPUIDLE_FLAG_IRQ_ENABLE) {
state->enter = intel_idle_irq;
} else if (force_irq_on) {
pr_info("forced intel_idle_irq for state %d\n", cstate);
state->enter = intel_idle_irq;
}
state_update_enter_method(state, cstate);
if ((disabled_states_mask & BIT(drv->state_count)) ||
((icpu->use_acpi || force_use_acpi) &&