From 69208c9e1e938cd115fdafdc502b5a7aa99d8d0b Mon Sep 17 00:00:00 2001
From: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Tue, 10 Oct 2017 11:18:16 +0200
Subject: [PATCH] drm/i915: Increase atomic update vblank evasion time with lockdep
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Git-commit: 69208c9e1e938cd115fdafdc502b5a7aa99d8d0b
Patch-mainline: v4.15-rc1
References: FATE#322643 bsc#1055900
All our mmio writes take forever with lockdep due to the constant
lock acquire&dropping we do. Ville has some patches to only acquire
the mmio spinlocks once instead for every single mmio, but those
aren't ready yet.
As an interim solution just extend our budget slightly when lockdep is
enabled, to avoid the rare and sporadic noise in CI.
V2: I forgot to add the FIXME comment ...
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=103169
References: https://bugs.freedesktop.org/show_bug.cgi?id=103124
References: https://bugs.freedesktop.org/show_bug.cgi?id=102403
References: https://bugs.freedesktop.org/show_bug.cgi?id=103020
References: https://bugs.freedesktop.org/show_bug.cgi?id=103019
References: https://bugs.freedesktop.org/show_bug.cgi?id=102723
References: https://bugs.freedesktop.org/show_bug.cgi?id=102544
References: https://bugs.freedesktop.org/show_bug.cgi?id=103180
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010091816.26898-1-daniel.vetter@ffwll.ch
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/intel_sprite.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -66,7 +66,13 @@ int intel_usecs_to_scanlines(const struc
1000 * adjusted_mode->crtc_htotal);
}
+/* FIXME: We should instead only take spinlocks once for the entire update
+ * instead of once per mmio. */
+#if IS_ENABLED(CONFIG_PROVE_LOCKING)
+#define VBLANK_EVASION_TIME_US 250
+#else
#define VBLANK_EVASION_TIME_US 100
+#endif
/**
* intel_pipe_update_start() - start update of a set of display registers