Avoid blocking the kworker by putting back the freed object list if we cannot immediately take the mutex. We will try again shortly, and flush the work when desperate. References: https://bugs.freedesktop.org/show_bug.cgi?id=100434 Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/i915_gem.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index ab77e38ec264..c2e5cb529b0f 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4200,7 +4200,19 @@ static void __i915_gem_free_objects(struct drm_i915_private *i915, { struct drm_i915_gem_object *obj, *on; - mutex_lock(&i915->drm.struct_mutex); + if (!mutex_trylock(&i915->drm.struct_mutex)) { + /* If we fail to acquire the struct_mutex, put back the + * freed list and we will try again in the future. By + * rescheduling the task we prevent us from blocking + * the worker indefinitely on a prolonged wait for + * struct_mutex. + */ + if (llist_add_batch(llist_reverse_order(freed), freed, + &i915->mm.free_list)) + schedule_work(&i915->mm.free_work); + return; + } + intel_runtime_pm_get(i915); llist_for_each_entry(obj, freed, freed) { struct i915_vma *vma, *vn; -- 2.11.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx