diff options
Diffstat (limited to 'debian/patches-rt/0264-drm-i915-Don-t-disable-interrupts-independently-of-t.patch')
-rw-r--r-- | debian/patches-rt/0264-drm-i915-Don-t-disable-interrupts-independently-of-t.patch | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/debian/patches-rt/0264-drm-i915-Don-t-disable-interrupts-independently-of-t.patch b/debian/patches-rt/0264-drm-i915-Don-t-disable-interrupts-independently-of-t.patch new file mode 100644 index 000000000..e95fb336e --- /dev/null +++ b/debian/patches-rt/0264-drm-i915-Don-t-disable-interrupts-independently-of-t.patch @@ -0,0 +1,51 @@ +From 31ae53586975d39dd03dabf5c944b498dcc73289 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Wed, 10 Apr 2019 11:01:37 +0200 +Subject: [PATCH 264/347] drm/i915: Don't disable interrupts independently of + the lock +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz + +The locks (timeline->lock and rq->lock) need to be taken with disabled +interrupts. This is done in __retire_engine_request() by disabling the +interrupts independently of the locks itself. +While local_irq_disable()+spin_lock() equals spin_lock_irq() on vanilla +it does not on RT. Also, it is not obvious if there is a special reason +to why the interrupts are disabled independently of the lock. + +Enable/disable interrupts as part of the locking instruction. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> +--- + drivers/gpu/drm/i915/i915_request.c | 8 ++------ + 1 file changed, 2 insertions(+), 6 deletions(-) + +diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c +index 5c2c93cbab12..7124510b9131 100644 +--- a/drivers/gpu/drm/i915/i915_request.c ++++ b/drivers/gpu/drm/i915/i915_request.c +@@ -356,9 +356,7 @@ static void __retire_engine_request(struct intel_engine_cs *engine, + + GEM_BUG_ON(!i915_request_completed(rq)); + +- local_irq_disable(); +- +- spin_lock(&engine->timeline.lock); ++ spin_lock_irq(&engine->timeline.lock); + GEM_BUG_ON(!list_is_first(&rq->link, &engine->timeline.requests)); + list_del_init(&rq->link); + spin_unlock(&engine->timeline.lock); +@@ -372,9 +370,7 @@ static void __retire_engine_request(struct intel_engine_cs *engine, + GEM_BUG_ON(!atomic_read(&rq->i915->gt_pm.rps.num_waiters)); + atomic_dec(&rq->i915->gt_pm.rps.num_waiters); + } +- spin_unlock(&rq->lock); +- +- local_irq_enable(); ++ spin_unlock_irq(&rq->lock); + + /* + * The backing object for the context is done after switching to the +-- +2.36.1 + |