drm/i915: Try harder to finish the idle-worker

If a worker requeues itself, it may switch to a different kworker pool,
which flush_work() considers as complete. To be strict, we then need to
keep flushing the work until it is no longer pending.

References: https://bugs.freedesktop.org/show_bug.cgi?id=102456
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171006104038.22337-1-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2017-10-06 11:40:38 +01:00
parent bb8920f5be
commit 7c26240e8a
3 changed files with 15 additions and 4 deletions

View File

@ -4259,8 +4259,7 @@ fault_irq_set(struct drm_i915_private *i915,
mutex_unlock(&i915->drm.struct_mutex);
/* Flush idle worker to disarm irq */
while (flush_delayed_work(&i915->gt.idle_work))
;
drain_delayed_work(&i915->gt.idle_work);
return 0;

View File

@ -4547,8 +4547,7 @@ int i915_gem_suspend(struct drm_i915_private *dev_priv)
/* As the idle_work is rearming if it detects a race, play safe and
* repeat the flush until it is definitely idle.
*/
while (flush_delayed_work(&dev_priv->gt.idle_work))
;
drain_delayed_work(&dev_priv->gt.idle_work);
/* Assert that we sucessfully flushed all the work and
* reset the GPU back to its idle, low power state.

View File

@ -124,4 +124,17 @@ static inline void __list_del_many(struct list_head *head,
WRITE_ONCE(head->next, first);
}
/*
* Wait until the work is finally complete, even if it tries to postpone
* by requeueing itself. Note, that if the worker never cancels itself,
* we will spin forever.
*/
static inline void drain_delayed_work(struct delayed_work *dw)
{
do {
while (flush_delayed_work(dw))
;
} while (delayed_work_pending(dw));
}
#endif /* !__I915_UTILS_H */