From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu, 20 Feb 2020 12:36:07 +0000 (+0000)
Subject: drm/i915: Double check bumping after the spinlock
X-Git-Tag: v5.7-rc1~136^2~18^2~45
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=54738e8ad5a5e5eeab7cc762de022b00bcd9af9f;p=users%2Fjedix%2Flinux-maple.git

drm/i915: Double check bumping after the spinlock

In preparation for making GEM execbuf parallel, we need to be prepared
to handle very early declaration of dependencies -- even before our
signaler has itself been submitted.

References: a79ca656b648 ("drm/i915: Push the wakeref->count deferral to the backend")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200220123608.1666271-1-chris@chris-wilson.co.uk
---

diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c
index 59f70b674665..be770f2419b1 100644
--- a/drivers/gpu/drm/i915/i915_scheduler.c
+++ b/drivers/gpu/drm/i915/i915_scheduler.c
@@ -363,6 +363,9 @@ static void __bump_priority(struct i915_sched_node *node, unsigned int bump)
 {
 	struct i915_sched_attr attr = node->attr;
 
+	if (attr.priority & bump)
+		return;
+
 	attr.priority |= bump;
 	__i915_schedule(node, &attr);
 }