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This allows the runtime/app to execute > actions on signal reception before driver gets a chance to > move ahead with the sequence. > > Signed-off-by: Ahmad Rehman > --- > drivers/gpu/drm/amd/amdkfd/kfd_events.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c > index 82905f3e54dd..8dfb796fd506 100644 > --- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c > +++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c > @@ -1329,6 +1329,13 @@ void kfd_signal_reset_event(struct kfd_node *dev) > } > > rcu_read_unlock(); > + > + /* > + * Since the set_event is asynchronous, putting a delay > + * to give runtime sometime to act on the EXCEPTION before > + * driver moves ahead. > + */ > + ssleep(2); This adds a 2s sleep inside a loop that iterates over all processes using KFD. If you have multiple KFD processes running, that could add up to a significant delay. I also don't like waiting before the srcu_read_unlock, because that would block other threads synchronizing with the kfd_processes_srcu (mostly kfd_process_notifier_release). What exactly is it that you want to prevent "moving on" to here? Regards,   Felix > } > srcu_read_unlock(&kfd_processes_srcu, idx); > }