xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

drm/i915: Hold irq-off for the entire fake lock period

Browse Source 
Sadly lockdep records when the irqs are re-enabled and then marks up the
fake lock as being irq-unsafe. Our hand is forced and so we must mark up
the entire fake lock critical section as irq-off.

Hopefully this is the last tweak required!

v2: Not quite, we need to mark the timeline spinlock as irqsafe. That
was a genuine bug being hidden by the earlier lockdep splat.

Fixes: d67739268c ("drm/i915/gt: Mark up the nested engine-pm timeline lock as irqsafe")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823132700.25286-2-chris@chris-wilson.co.uk
(cherry picked from commit 6dcb85a0ad)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
This commit is contained in:
Chris Wilson
2019-08-23 14:26:46 +01:00
committed by Rodrigo Vivi
parent 0ac072cced
commit ff36c5c4fd
5 changed files with 42 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/gpu/drm/i915/i915_request.c
View File

@@ -1465,9 +1465,10 @@ bool i915_retire_requests(struct drm_i915_private *i915)
{
struct intel_gt_timelines *timelines = &i915->gt.timelines;
struct intel_timeline *tl, *tn;
unsigned long flags;
LIST_HEAD(free);
spin_lock(&timelines->lock);
spin_lock_irqsave(&timelines->lock, flags);
list_for_each_entry_safe(tl, tn, &timelines->active_list, link) {
if (!mutex_trylock(&tl->mutex))
continue;
@@ -1475,11 +1476,11 @@ bool i915_retire_requests(struct drm_i915_private *i915)
intel_timeline_get(tl);
GEM_BUG_ON(!tl->active_count);
tl->active_count++; /* pin the list element */
spin_unlock(&timelines->lock);
spin_unlock_irqrestore(&timelines->lock, flags);
retire_requests(tl);
spin_lock(&timelines->lock);
spin_lock_irqsave(&timelines->lock, flags);
/* Resume iteration after dropping lock */
list_safe_reset_next(tl, tn, link);
@@ -1494,7 +1495,7 @@ bool i915_retire_requests(struct drm_i915_private *i915)
list_add(&tl->link, &free);
}
}
spin_unlock(&timelines->lock);
spin_unlock_irqrestore(&timelines->lock, flags);
list_for_each_entry_safe(tl, tn, &free, link)
__intel_timeline_free(&tl->kref);