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When FD is closing, IOCTLs presumably > can't be modifying the xarray. > > v2: Update commit text (Matt Brost) > v3: Add more code comment (Rodrigo Vivi) > > Signed-off-by: Niranjana Vishwanathapura > Reviewed-by: Matthew Brost > Reviewed-by: Jagmeet Randhawa > --- > drivers/gpu/drm/xe/xe_device.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c > index f04b11e45c2d..bf4c4306f6d3 100644 > --- a/drivers/gpu/drm/xe/xe_device.c > +++ b/drivers/gpu/drm/xe/xe_device.c > @@ -96,12 +96,15 @@ static void xe_file_close(struct drm_device *dev, struct drm_file *file) > struct xe_exec_queue *q; > unsigned long idx; > > - mutex_lock(&xef->exec_queue.lock); > + /* > + * No need for exec_queue.lock here as there is no contention at > + * this point. I'm really sorry to be pedantic here. "But why is there no contention at this point?" This remain unanswered here in the comment, and only a further code inspection or a git-blame archeology would lead to the commit message with: "When FD is closing, IOCTLs presumably can't be modifying the xarray." > Taking exec_queue.lock here causes undue dependency > + * on vm->lock taken during xe_exec_queue_kill(). > + */ > xa_for_each(&xef->exec_queue.xa, idx, q) { > xe_exec_queue_kill(q); > xe_exec_queue_put(q); > } > - mutex_unlock(&xef->exec_queue.lock); > xa_destroy(&xef->exec_queue.xa); > mutex_destroy(&xef->exec_queue.lock); > mutex_lock(&xef->vm.lock); > -- > 2.43.0 >