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cpufreq: intel_pstate: Simplify spinlock locking

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Because intel_pstate_enable/disable_hwp_interrupt() are only called from
thread context, they need not save the IRQ flags when using a spinlock
as interrupts are guaranteed to be enabled when they run, so make them
use spin_lock/unlock_irq().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Rafael J. Wysocki
2024-03-21 20:30:42 +01:00
parent f186b2dace
commit 12ebba42d2
1 changed files with 4 additions and 8 deletions
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12
drivers/cpufreq/intel_pstate.c
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@@ -1682,30 +1682,26 @@ void notify_hwp_interrupt(void)
static void intel_pstate_disable_hwp_interrupt(struct cpudata *cpudata)
{
unsigned long flags;
if (!boot_cpu_has(X86_FEATURE_HWP_NOTIFY))
return;
/* wrmsrl_on_cpu has to be outside spinlock as this can result in IPC */
wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
spin_lock_irqsave(&hwp_notify_lock, flags);
spin_lock_irq(&hwp_notify_lock);
if (cpumask_test_and_clear_cpu(cpudata->cpu, &hwp_intr_enable_mask))
cancel_delayed_work(&cpudata->hwp_notify_work);
spin_unlock_irqrestore(&hwp_notify_lock, flags);
spin_unlock_irq(&hwp_notify_lock);
}
static void intel_pstate_enable_hwp_interrupt(struct cpudata *cpudata)
{
/* Enable HWP notification interrupt for guaranteed performance change */
if (boot_cpu_has(X86_FEATURE_HWP_NOTIFY)) {
unsigned long flags;
spin_lock_irqsave(&hwp_notify_lock, flags);
spin_lock_irq(&hwp_notify_lock);
INIT_DELAYED_WORK(&cpudata->hwp_notify_work, intel_pstate_notify_work);
cpumask_set_cpu(cpudata->cpu, &hwp_intr_enable_mask);
spin_unlock_irqrestore(&hwp_notify_lock, flags);
spin_unlock_irq(&hwp_notify_lock);
/* wrmsrl_on_cpu has to be outside spinlock as this can result in IPC */
wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x01);