Merge tag 'irq-core-2020-12-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq updates from Thomas Gleixner:
 "This is the second attempt after the first one failed miserably and
  got zapped to unblock the rest of the interrupt related patches.

  A treewide cleanup of interrupt descriptor (ab)use with all sorts of
  racy accesses, inefficient and disfunctional code. The goal is to
  remove the export of irq_to_desc() to prevent these things from
  creeping up again"

* tag 'irq-core-2020-12-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  genirq: Restrict export of irq_to_desc()
  xen/events: Implement irq distribution
  xen/events: Reduce irq_info:: Spurious_cnt storage size
  xen/events: Only force affinity mask for percpu interrupts
  xen/events: Use immediate affinity setting
  xen/events: Remove disfunct affinity spreading
  xen/events: Remove unused bind_evtchn_to_irq_lateeoi()
  net/mlx5: Use effective interrupt affinity
  net/mlx5: Replace irq_to_desc() abuse
  net/mlx4: Use effective interrupt affinity
  net/mlx4: Replace irq_to_desc() abuse
  PCI: mobiveil: Use irq_data_get_irq_chip_data()
  PCI: xilinx-nwl: Use irq_data_get_irq_chip_data()
  NTB/msi: Use irq_has_action()
  mfd: ab8500-debugfs: Remove the racy fiddling with irq_desc
  pinctrl: nomadik: Use irq_has_action()
  drm/i915/pmu: Replace open coded kstat_irqs() copy
  drm/i915/lpe_audio: Remove pointless irq_to_desc() usage
  s390/irq: Use irq_desc_kstat_cpu() in show_msi_interrupt()
  parisc/irq: Use irq_desc_kstat_cpu() in show_interrupts()
  ...

1 files changed, 34 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index c80eeac53952..6cdb052e3850 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -60,6 +60,24 @@
  * and related files, but that will be described in separate chapters.
  */
 
+/*
+ * Interrupt statistic for PMU. Increments the counter only if the
+ * interrupt originated from the the GPU so interrupts from a device which
+ * shares the interrupt line are not accounted.
+ */
+static inline void pmu_irq_stats(struct drm_i915_private *i915,
+				 irqreturn_t res)
+{
+	if (unlikely(res != IRQ_HANDLED))
+		return;
+
+	/*
+	 * A clever compiler translates that into INC. A not so clever one
+	 * should at least prevent store tearing.
+	 */
+	WRITE_ONCE(i915->pmu.irq_count, i915->pmu.irq_count + 1);
+}
+
 typedef bool (*long_pulse_detect_func)(enum hpd_pin pin, u32 val);
 typedef u32 (*hotplug_enables_func)(struct drm_i915_private *i915,
 				    enum hpd_pin pin);
@@ -1668,6 +1686,8 @@ static irqreturn_t valleyview_irq_handler(int irq, void *arg)
 		valleyview_pipestat_irq_handler(dev_priv, pipe_stats);
 	} while (0);
 
+	pmu_irq_stats(dev_priv, ret);
+
 	enable_rpm_wakeref_asserts(&dev_priv->runtime_pm);
 
 	return ret;
@@ -1745,6 +1765,8 @@ static irqreturn_t cherryview_irq_handler(int irq, void *arg)
 		valleyview_pipestat_irq_handler(dev_priv, pipe_stats);
 	} while (0);
 
+	pmu_irq_stats(dev_priv, ret);
+
 	enable_rpm_wakeref_asserts(&dev_priv->runtime_pm);
 
 	return ret;
@@ -2155,6 +2177,8 @@ static irqreturn_t ilk_irq_handler(int irq, void *arg)
 	if (sde_ier)
 		raw_reg_write(regs, SDEIER, sde_ier);
 
+	pmu_irq_stats(i915, ret);
+
 	/* IRQs are synced during runtime_suspend, we don't require a wakeref */
 	enable_rpm_wakeref_asserts(&i915->runtime_pm);
 
@@ -2541,6 +2565,8 @@ static irqreturn_t gen8_irq_handler(int irq, void *arg)
 
 	gen8_master_intr_enable(regs);
 
+	pmu_irq_stats(dev_priv, IRQ_HANDLED);
+
 	return IRQ_HANDLED;
 }
 
@@ -2636,6 +2662,8 @@ __gen11_irq_handler(struct drm_i915_private * const i915,
 
 	gen11_gu_misc_irq_handler(gt, gu_misc_iir);
 
+	pmu_irq_stats(i915, IRQ_HANDLED);
+
 	return IRQ_HANDLED;
 }
 
@@ -3934,6 +3962,8 @@ static irqreturn_t i8xx_irq_handler(int irq, void *arg)
 		i8xx_pipestat_irq_handler(dev_priv, iir, pipe_stats);
 	} while (0);
 
+	pmu_irq_stats(dev_priv, ret);
+
 	enable_rpm_wakeref_asserts(&dev_priv->runtime_pm);
 
 	return ret;
@@ -4043,6 +4073,8 @@ static irqreturn_t i915_irq_handler(int irq, void *arg)
 		i915_pipestat_irq_handler(dev_priv, iir, pipe_stats);
 	} while (0);
 
+	pmu_irq_stats(dev_priv, ret);
+
 	enable_rpm_wakeref_asserts(&dev_priv->runtime_pm);
 
 	return ret;
@@ -4189,6 +4221,8 @@ static irqreturn_t i965_irq_handler(int irq, void *arg)
 		i965_pipestat_irq_handler(dev_priv, iir, pipe_stats);
 	} while (0);
 
+	pmu_irq_stats(dev_priv, IRQ_HANDLED);
+
 	enable_rpm_wakeref_asserts(&dev_priv->runtime_pm);
 
 	return ret;