Commit 8b4865cd authored by Uwe Kleine-König's avatar Uwe Kleine-König Committed by Rafael J. Wysocki
Browse files

cpufreq: intel_pstate: Make hwp_notify_lock a raw spinlock 



notify_hwp_interrupt() is called via sysvec_thermal() ->
smp_thermal_vector() -> intel_thermal_interrupt() in hard irq context.
For this reason it must not use a simple spin_lock that sleeps with
PREEMPT_RT enabled. So convert it to a raw spinlock.

Reported-by: default avatarxiao sheng wen <atzlinux@sina.com>
Link: https://bugs.debian.org/1076483


Signed-off-by: default avatarUwe Kleine-König <ukleinek@debian.org>
Acked-by: default avatarSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: default avatarxiao sheng wen <atzlinux@sina.com>
Link: https://patch.msgid.link/20240919081121.10784-2-ukleinek@debian.org


Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 9852d85e

drivers/cpufreq/intel_pstate.c

+8 −8
Original line number Diff line number Diff line
@@ -1845,7 +1845,7 @@ static void intel_pstate_notify_work(struct work_struct *work) 
	wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_STATUS, 0);

}



static DEFINE_SPINLOCK(hwp_notify_lock);

static DEFINE_RAW_SPINLOCK(hwp_notify_lock);

static cpumask_t hwp_intr_enable_mask;



#define HWP_GUARANTEED_PERF_CHANGE_STATUS      BIT(0)
@@ -1868,7 +1868,7 @@ void notify_hwp_interrupt(void) 
	if (!(value & status_mask))

		return;



	spin_lock_irqsave(&hwp_notify_lock, flags);

	raw_spin_lock_irqsave(&hwp_notify_lock, flags);



	if (!cpumask_test_cpu(this_cpu, &hwp_intr_enable_mask))

		goto ack_intr;
@@ -1876,13 +1876,13 @@ void notify_hwp_interrupt(void) 
	schedule_delayed_work(&all_cpu_data[this_cpu]->hwp_notify_work,

			      msecs_to_jiffies(10));



	spin_unlock_irqrestore(&hwp_notify_lock, flags);

	raw_spin_unlock_irqrestore(&hwp_notify_lock, flags);



	return;



ack_intr:

	wrmsrl_safe(MSR_HWP_STATUS, 0);

	spin_unlock_irqrestore(&hwp_notify_lock, flags);

	raw_spin_unlock_irqrestore(&hwp_notify_lock, flags);

}



static void intel_pstate_disable_hwp_interrupt(struct cpudata *cpudata)
@@ -1895,9 +1895,9 @@ static void intel_pstate_disable_hwp_interrupt(struct cpudata *cpudata) 
	/* 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_irq(&hwp_notify_lock);

	raw_spin_lock_irq(&hwp_notify_lock);

	cancel_work = cpumask_test_and_clear_cpu(cpudata->cpu, &hwp_intr_enable_mask);

	spin_unlock_irq(&hwp_notify_lock);

	raw_spin_unlock_irq(&hwp_notify_lock);



	if (cancel_work)

		cancel_delayed_work_sync(&cpudata->hwp_notify_work);
@@ -1912,10 +1912,10 @@ static void intel_pstate_enable_hwp_interrupt(struct cpudata *cpudata) 
	if (boot_cpu_has(X86_FEATURE_HWP_NOTIFY)) {

		u64 interrupt_mask = HWP_GUARANTEED_PERF_CHANGE_REQ;



		spin_lock_irq(&hwp_notify_lock);

		raw_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_irq(&hwp_notify_lock);

		raw_spin_unlock_irq(&hwp_notify_lock);



		if (cpu_feature_enabled(X86_FEATURE_HWP_HIGHEST_PERF_CHANGE))

			interrupt_mask |= HWP_HIGHEST_PERF_CHANGE_REQ;