It turns out that idr_for_each_entry is really slow compared to just iterating over the slots. Based on measurements the difference is estimated to be about a factor 64. That means using idr_for_each_entry is only worth it with very few allocated events. Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com> --- drivers/gpu/drm/amd/amdkfd/kfd_events.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c index bccf2f7..7862fcf 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c @@ -496,7 +496,7 @@ void kfd_signal_event_interrupt(unsigned int pasid, uint32_t partial_id, pr_debug_ratelimited("Partial ID invalid: %u (%u valid bits)\n", partial_id, valid_id_bits); - if (p->signal_event_count < KFD_SIGNAL_EVENT_LIMIT/2) { + if (p->signal_event_count < KFD_SIGNAL_EVENT_LIMIT/64) { /* With relatively few events, it's faster to * iterate over the event IDR */ -- 2.7.4