[Intel-gfx] [PATCH 3/3] drm: Add a debug print for drm_modeset_backoff()

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Logs can get confusing when some operations are done multiple times
due to the ww mutex backoff. Add a debug print into
drm_modeset_backoff() so that at least the reason for the odd
looking logs will be obvious.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/drm_modeset_lock.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c
index 81dd11901ffd..1277ff18d993 100644
--- a/drivers/gpu/drm/drm_modeset_lock.c
+++ b/drivers/gpu/drm/drm_modeset_lock.c
@@ -295,6 +295,8 @@ int drm_modeset_backoff(struct drm_modeset_acquire_ctx *ctx)
 {
 	struct drm_modeset_lock *contended = ctx->contended;
 
+	DRM_DEBUG_KMS("Retrying to avoid deadlock\n");
+
 	ctx->contended = NULL;
 
 	if (WARN_ON(!contended))
-- 
2.19.2