[PATCH 08/13] drm_print: interpose drm_*dbg with forwarding macros

Jim Cromie jim.cromie at gmail.com
Thu Feb 17 03:48:24 UTC 2022


drm_dev_dbg() & drm_dbg() sit below the categorized layer of the DRM
debug API, and implement most of it.  These are good places to insert
dynamic-debug jump-label mechanics, allowing DRM to avoid the runtime
cost of drm_debug_enabled().

Set up for this by changing the func names by adding '__' prefixes,
and define forwarding macros to the new names.

no functional changes.

memory cost baseline: (unchanged)
bash-5.1# drms_load
[    9.220389] dyndbg:   1 debug prints in module drm
[    9.224426] ACPI: bus type drm_connector registered
[    9.302192] dyndbg:   2 debug prints in module ttm
[    9.305033] dyndbg:   8 debug prints in module video
[    9.627563] dyndbg: 127 debug prints in module i915
[    9.721505] AMD-Vi: AMD IOMMUv2 functionality not available on this system - This is not a bug.
[   10.091345] dyndbg: 2196 debug prints in module amdgpu
[   10.106589] [drm] amdgpu kernel modesetting enabled.
[   10.107270] amdgpu: CRAT table not found
[   10.107926] amdgpu: Virtual CRAT table created for CPU
[   10.108398] amdgpu: Topology: Add CPU node
[   10.168507] dyndbg:   3 debug prints in module wmi
[   10.329587] dyndbg:   3 debug prints in module nouveau

Signed-off-by: Jim Cromie <jim.cromie at gmail.com>
---
 drivers/gpu/drm/drm_print.c | 10 +++++-----
 include/drm/drm_print.h     |  9 +++++++--
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index f783d4963d4b..e45ba224e57c 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -256,8 +256,8 @@ 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(const struct device *dev, enum drm_debug_category category,
+		   const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;
@@ -278,9 +278,9 @@ void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
 
 	va_end(args);
 }
-EXPORT_SYMBOL(drm_dev_dbg);
+EXPORT_SYMBOL(__drm_dev_dbg);
 
-void __drm_dbg(enum drm_debug_category category, const char *format, ...)
+void ___drm_dbg(enum drm_debug_category category, const char *format, ...)
 {
 	struct va_format vaf;
 	va_list args;
@@ -297,7 +297,7 @@ void __drm_dbg(enum drm_debug_category category, const char *format, ...)
 
 	va_end(args);
 }
-EXPORT_SYMBOL(__drm_dbg);
+EXPORT_SYMBOL(___drm_dbg);
 
 void __drm_err(const char *format, ...)
 {
diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h
index b3b470440e46..4bed99326631 100644
--- a/include/drm/drm_print.h
+++ b/include/drm/drm_print.h
@@ -334,7 +334,7 @@ __printf(3, 4)
 void drm_dev_printk(const struct device *dev, const char *level,
 		    const char *format, ...);
 __printf(3, 4)
-void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
+void __drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
 		 const char *format, ...);
 
 /**
@@ -383,6 +383,9 @@ void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
 	}								\
 })
 
+#define drm_dev_dbg(dev, cat, fmt, ...)				\
+	__drm_dev_dbg(dev, cat, fmt, ##__VA_ARGS__)
+
 /**
  * DRM_DEV_DEBUG() - Debug output for generic drm code
  *
@@ -484,10 +487,12 @@ void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
  */
 
 __printf(2, 3)
-void __drm_dbg(enum drm_debug_category category, const char *format, ...);
+void ___drm_dbg(enum drm_debug_category category, const char *format, ...);
 __printf(1, 2)
 void __drm_err(const char *format, ...);
 
+#define __drm_dbg(fmt, ...)		___drm_dbg(fmt, ##__VA_ARGS__)
+
 /* Macros to make printk easier */
 
 #define _DRM_PRINTK(once, level, fmt, ...)				\
-- 
2.35.1



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