From b4e3c935b2313b3e557066b630efd0367c7fb34c Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed, 22 Nov 2017 22:25:10 +0000
Subject: [PATCH] drm/i915: Save/restore irq state for vlv_residency_raw()
Git-commit: b4e3c935b2313b3e557066b630efd0367c7fb34c
Patch-mainline: v4.16-rc1
References: FATE#322643 bsc#1055900
Since commit 6060b6aec03c ("drm/i915/pmu: Add RC6 residency metrics"),
vlv_residency_raw() may be called from an irq-disabled context (via perf
event sampling on remote cpu). As such, we can no longer assume that we
are called from process context and must save/restore the irq state for
the spinlock.
Fixes: 6060b6aec03c ("drm/i915/pmu: Add RC6 residency metrics")
Testcase: igt/perf_pmu/other-init-3
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171122222510.22627-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/intel_pm.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -9396,12 +9396,13 @@ static u64 vlv_residency_raw(struct drm_
const i915_reg_t reg)
{
u32 lower, upper, tmp;
+ unsigned long flags;
int loop = 2;
/* The register accessed do not need forcewake. We borrow
* uncore lock to prevent concurrent access to range reg.
*/
- spin_lock_irq(&dev_priv->uncore.lock);
+ spin_lock_irqsave(&dev_priv->uncore.lock, flags);
/* vlv and chv residency counters are 40 bits in width.
* With a control bit, we can choose between upper or lower
@@ -9432,7 +9433,7 @@ static u64 vlv_residency_raw(struct drm_
* now.
*/
- spin_unlock_irq(&dev_priv->uncore.lock);
+ spin_unlock_irqrestore(&dev_priv->uncore.lock, flags);
return lower | (u64)upper << 8;
}
@@ -9451,7 +9452,6 @@ u64 intel_rc6_residency_ns(struct drm_i9
mul = 1000000;
div = dev_priv->czclk_freq;
time_hw = vlv_residency_raw(dev_priv, reg);
-
} else {
/* 833.33ns units on Gen9LP, 1.28us elsewhere. */
if (IS_GEN9_LP(dev_priv)) {