diff options
Diffstat (limited to 'debian/patches-rt/0025-drm-i915-Don-t-check-for-atomic-context-on-PREEMPT_R.patch')
| -rw-r--r-- | debian/patches-rt/0025-drm-i915-Don-t-check-for-atomic-context-on-PREEMPT_R.patch | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/debian/patches-rt/0025-drm-i915-Don-t-check-for-atomic-context-on-PREEMPT_R.patch b/debian/patches-rt/0025-drm-i915-Don-t-check-for-atomic-context-on-PREEMPT_R.patch new file mode 100644 index 000000000..2bbcdfed9 --- /dev/null +++ b/debian/patches-rt/0025-drm-i915-Don-t-check-for-atomic-context-on-PREEMPT_R.patch @@ -0,0 +1,36 @@ +From d9970290d810087f44a37de7ae6f3638ecddd3a0 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Mon, 25 Oct 2021 15:05:18 +0200 +Subject: [PATCH 25/62] drm/i915: Don't check for atomic context on PREEMPT_RT +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.1/older/patches-6.1.69-rt21.tar.xz + +The !in_atomic() check in _wait_for_atomic() triggers on PREEMPT_RT +because the uncore::lock is a spinlock_t and does not disable +preemption or interrupts. + +Changing the uncore:lock to a raw_spinlock_t doubles the worst case +latency on an otherwise idle testbox during testing. Therefore I'm +currently unsure about changing this. + +Link: https://lore.kernel.org/all/20211006164628.s2mtsdd2jdbfyf7g@linutronix.de/ +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + drivers/gpu/drm/i915/i915_utils.h | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/drivers/gpu/drm/i915/i915_utils.h b/drivers/gpu/drm/i915/i915_utils.h +index 6c14d13364bf..de58855e6926 100644 +--- a/drivers/gpu/drm/i915/i915_utils.h ++++ b/drivers/gpu/drm/i915/i915_utils.h +@@ -294,7 +294,7 @@ wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms) + #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000) + + /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */ +-#if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT) ++#if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT) && !defined(CONFIG_PREEMPT_RT) + # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic()) + #else + # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0) +-- +2.43.0 + |