drm_print: add _ddebug descriptor to drm_*dbg prototypes

upgrade the callchain to drm_dbg() and drm_dev_dbg(); add a struct
_ddebug ptr parameter to them, and supply that additional param by
replacing the '_no_desc' flavor of dyndbg Factory macro currently used
with the flavor that supplies the descriptor.

NOTES:

The descriptor gives these fns access to the decorator flags, but they
do none of the dynamic-prefixing done by dynamic_emit_prefix(), which
is currently static.

DRM already has conventions for logging/messaging; just tossing
optional decorations on top probably wouldn't help.  Instead, existing
flags (or new ones, perhaps 'sd' ala lspci) can be used to make
current message conventions optional.  This suggests a new
drmdbg_prefix_emit() to handle prefixing locally.

For CONFIG_DRM_USE_DYNAMIC_DEBUG=N, just pass null descriptor.

desc->class_id is redundant with category parameter, but its
availability is dependent on desc.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20220912052852.1123868-10-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 5 insertions, 3 deletions

diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index ec477c44a784..5b93c11895bb 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -29,6 +29,7 @@
 #include <linux/moduleparam.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
+#include <linux/dynamic_debug.h>
 
 #include <drm/drm.h>
 #include <drm/drm_drv.h>
@@ -278,8 +279,8 @@ void drm_dev_printk(const struct device *dev, const char *level,
 }
 EXPORT_SYMBOL(drm_dev_printk);
 
-void __drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
-		   const char *format, ...)
+void __drm_dev_dbg(struct _ddebug *desc, const struct device *dev,
+		   enum drm_debug_category category, const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;
@@ -287,6 +288,7 @@ void __drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
 	if (!__drm_debug_enabled(category))
 		return;
 
+	/* we know we are printing for either syslog, tracefs, or both */
 	va_start(args, format);
 	vaf.fmt = format;
 	vaf.va = &args;
@@ -302,7 +304,7 @@ void __drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
 }
 EXPORT_SYMBOL(__drm_dev_dbg);
 
-void ___drm_dbg(enum drm_debug_category category, const char *format, ...)
+void ___drm_dbg(struct _ddebug *desc, enum drm_debug_category category, const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;