From b0cebca5e589ca58fb6f277f75d185e424c04829 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed, 20 Nov 2019 17:08:58 +0000
Subject: drm/i915/gt: Declare timeline.lock to be irq-free
Git-commit: 88cec4973de1d096282565779bbd9d5c6412a293
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
Now that we never allow the intel_wakeref callbacks to be invoked from
interrupt context, we do not need the irqsafe spinlock for the timeline.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191120170858.3965380-1-chris@chris-wilson.co.uk
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gt/intel_gt_requests.c | 9 ++++-----
drivers/gpu/drm/i915/gt/intel_reset.c | 9 ++++-----
drivers/gpu/drm/i915/gt/intel_timeline.c | 10 ++++------
3 files changed, 12 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
index 028044cd3443..8cb5421e5f0e 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
@@ -109,7 +109,6 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
struct intel_gt_timelines *timelines = >->timelines;
struct intel_timeline *tl, *tn;
unsigned long active_count = 0;
- unsigned long flags;
bool interruptible;
LIST_HEAD(free);
@@ -119,7 +118,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
flush_submission(gt); /* kick the ksoftirqd tasklets */
- spin_lock_irqsave(&timelines->lock, flags);
+ spin_lock(&timelines->lock);
list_for_each_entry_safe(tl, tn, &timelines->active_list, link) {
if (!mutex_trylock(&tl->mutex)) {
active_count++; /* report busy to caller, try again? */
@@ -129,7 +128,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
intel_timeline_get(tl);
GEM_BUG_ON(!atomic_read(&tl->active_count));
atomic_inc(&tl->active_count); /* pin the list element */
- spin_unlock_irqrestore(&timelines->lock, flags);
+ spin_unlock(&timelines->lock);
if (timeout > 0) {
struct dma_fence *fence;
@@ -145,7 +144,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
retire_requests(tl);
- spin_lock_irqsave(&timelines->lock, flags);
+ spin_lock(&timelines->lock);
/* Resume iteration after dropping lock */
list_safe_reset_next(tl, tn, link);
@@ -162,7 +161,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
list_add(&tl->link, &free);
}
}
- spin_unlock_irqrestore(&timelines->lock, flags);
+ spin_unlock(&timelines->lock);
list_for_each_entry_safe(tl, tn, &free, link)
__intel_timeline_free(&tl->kref);
diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
index 0388f9375366..36189238e13c 100644
--- a/drivers/gpu/drm/i915/gt/intel_reset.c
+++ b/drivers/gpu/drm/i915/gt/intel_reset.c
@@ -831,7 +831,6 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt)
{
struct intel_gt_timelines *timelines = >->timelines;
struct intel_timeline *tl;
- unsigned long flags;
bool ok;
if (!test_bit(I915_WEDGED, >->reset.flags))
@@ -853,7 +852,7 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt)
*
* No more can be submitted until we reset the wedged bit.
*/
- spin_lock_irqsave(&timelines->lock, flags);
+ spin_lock(&timelines->lock);
list_for_each_entry(tl, &timelines->active_list, link) {
struct dma_fence *fence;
@@ -861,7 +860,7 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt)
if (!fence)
continue;
- spin_unlock_irqrestore(&timelines->lock, flags);
+ spin_unlock(&timelines->lock);
/*
* All internal dependencies (i915_requests) will have
@@ -874,10 +873,10 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt)
dma_fence_put(fence);
/* Restart iteration after droping lock */
- spin_lock_irqsave(&timelines->lock, flags);
+ spin_lock(&timelines->lock);
tl = list_entry(&timelines->active_list, typeof(*tl), link);
}
- spin_unlock_irqrestore(&timelines->lock, flags);
+ spin_unlock(&timelines->lock);
/* We must reset pending GPU events before restoring our submission */
ok = !HAS_EXECLISTS(gt->i915); /* XXX better agnosticism desired */
diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c
index 4fb55b5867a1..c1d2419444f8 100644
--- a/drivers/gpu/drm/i915/gt/intel_timeline.c
+++ b/drivers/gpu/drm/i915/gt/intel_timeline.c
@@ -333,7 +333,6 @@ int intel_timeline_pin(struct intel_timeline *tl)
void intel_timeline_enter(struct intel_timeline *tl)
{
struct intel_gt_timelines *timelines = &tl->gt->timelines;
- unsigned long flags;
/*
* Pretend we are serialised by the timeline->mutex.
@@ -359,16 +358,15 @@ void intel_timeline_enter(struct intel_timeline *tl)
if (atomic_add_unless(&tl->active_count, 1, 0))
return;
- spin_lock_irqsave(&timelines->lock, flags);
+ spin_lock(&timelines->lock);
if (!atomic_fetch_inc(&tl->active_count))
list_add_tail(&tl->link, &timelines->active_list);
- spin_unlock_irqrestore(&timelines->lock, flags);
+ spin_unlock(&timelines->lock);
}
void intel_timeline_exit(struct intel_timeline *tl)
{
struct intel_gt_timelines *timelines = &tl->gt->timelines;
- unsigned long flags;
/* See intel_timeline_enter() */
lockdep_assert_held(&tl->mutex);
@@ -377,10 +375,10 @@ void intel_timeline_exit(struct intel_timeline *tl)
if (atomic_add_unless(&tl->active_count, -1, 1))
return;
- spin_lock_irqsave(&timelines->lock, flags);
+ spin_lock(&timelines->lock);
if (atomic_dec_and_test(&tl->active_count))
list_del(&tl->link);
- spin_unlock_irqrestore(&timelines->lock, flags);
+ spin_unlock(&timelines->lock);
/*
* Since this timeline is idle, all bariers upon which we were waiting
--
2.28.0