drm: Add ratelimited versions of the DRM_DEBUG* macros

There's a couple of places where this would be useful for drivers (such
as reporting DP aux transaction timeouts).

Signed-off-by: Lyude <cpaul@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470443443-27252-7-git-send-email-cpaul@redhat.com

1 files changed, 30 insertions, 0 deletions

diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 856c174bd730..f8e87fde611b 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -232,6 +232,36 @@ void drm_err(const char *format, ...);
                         drm_ut_debug_printk(__func__, fmt, ##args);     \
         } while (0)
 
+#define _DRM_DEFINE_DEBUG_RATELIMITED(level, fmt, args...)              \
+        do {                                                            \
+                if (unlikely(drm_debug & DRM_UT_ ## level)) {           \
+                        static DEFINE_RATELIMIT_STATE(                  \
+                                _rs,                                    \
+                                DEFAULT_RATELIMIT_INTERVAL,             \
+                                DEFAULT_RATELIMIT_BURST);               \
+                                                                        \
+                        if (__ratelimit(&_rs)) {                        \
+                                drm_ut_debug_printk(__func__, fmt,      \
+                                                    ##args);            \
+                        }                                               \
+                }                                                       \
+        } while (0)
+
+/**
+ * Rate limited debug output. Like DRM_DEBUG() but won't flood the log.
+ *
+ * \param fmt printf() like format string.
+ * \param arg arguments
+ */
+#define DRM_DEBUG_RATELIMITED(fmt, args...)                             \
+        _DRM_DEFINE_DEBUG_RATELIMITED(CORE, fmt, ##args)
+#define DRM_DEBUG_DRIVER_RATELIMITED(fmt, args...)                      \
+        _DRM_DEFINE_DEBUG_RATELIMITED(DRIVER, fmt, ##args)
+#define DRM_DEBUG_KMS_RATELIMITED(fmt, args...)                         \
+        _DRM_DEFINE_DEBUG_RATELIMITED(KMS, fmt, ##args)
+#define DRM_DEBUG_PRIME_RATELIMITED(fmt, args...)                       \
+        _DRM_DEFINE_DEBUG_RATELIMITED(PRIME, fmt, ##args)
+
 /*@}*/
 
 /***********************************************************************/