drm/i915/fdinfo: Don't show engine classes not present

Stop displaying engine classes with no engines - it is not a huge problem
if they are shown, since the values will correctly be all zeroes, but it
does count as misleading.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 055634e4b62f ("drm/i915: Expose client engine utilisation via fdinfo")
Cc: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220616140056.559074-1-tvrtko.ursulin@linux.intel.com
(cherry picked from commit 9f1b1d0b2242171b2891a0398def233801601c14)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/i915_drm_client.c b/drivers/gpu/drm/i915/i915_drm_client.c
index 18d38cb..b09d1d3 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drm_client.c
+++ b/drivers/gpu/drm/i915/i915_drm_client.c
@@ -116,8 +116,9 @@ show_client_class(struct seq_file *m,
                total += busy_add(ctx, class);
        rcu_read_unlock();
 
-       seq_printf(m, "drm-engine-%s:\t%llu ns\n",
-                  uabi_class_names[class], total);
+       if (capacity)
+               seq_printf(m, "drm-engine-%s:\t%llu ns\n",
+                          uabi_class_names[class], total);
 
        if (capacity > 1)
                seq_printf(m, "drm-engine-capacity-%s:\t%u\n",