Commit 84ec6728 authored by Jim Cromie's avatar Jim Cromie Committed by Greg Kroah-Hartman
Browse files

drm_print: wrap drm_*_dbg in dyndbg descriptor factory macro 



For CONFIG_DRM_USE_DYNAMIC_DEBUG=y, wrap __drm_dbg() & __drm_dev_dbg()
in one of dyndbg's Factory macros: _dynamic_func_call_no_desc().

This adds the callsite descriptor into the code, and an entry for each
into /proc/dynamic_debug/control.

  #> echo class DRM_UT_ATOMIC +p > /proc/dynamic_debug/control

CONFIG_DRM_USE_DYNAMIC_DEBUG=y/n is configurable because of the .data
footprint cost of per-callsite control; 56 bytes/site * ~2k for i915,
~4k callsites for amdgpu.  This is large enough that a kernel builder
might not want it.

Signed-off-by: default avatarJim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20220912052852.1123868-5-jim.cromie@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent e820f525

drivers/gpu/drm/Kconfig

+12 −0
Original line number Diff line number Diff line
@@ -50,6 +50,18 @@ config DRM_DEBUG_MM 


	  If in doubt, say "N".



config DRM_USE_DYNAMIC_DEBUG

	bool "use dynamic debug to implement drm.debug"

	default y

	depends on DRM

	depends on DYNAMIC_DEBUG || DYNAMIC_DEBUG_CORE

	depends on JUMP_LABEL

	help

	  Use dynamic-debug to avoid drm_debug_enabled() runtime overheads.

	  Due to callsite counts in DRM drivers (~4k in amdgpu) and 56

	  bytes per callsite, the .data costs can be substantial, and

	  are therefore configurable.



config DRM_DEBUG_SELFTEST

	tristate "kselftests for DRM"

	depends on DRM

drivers/gpu/drm/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -3,6 +3,8 @@ 
# Makefile for the drm device driver.  This driver provides support for the

# Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher.



CFLAGS-$(CONFIG_DRM_USE_DYNAMIC_DEBUG)	+= -DDYNAMIC_DEBUG_MODULE



drm-y       :=	drm_aperture.o drm_auth.o drm_cache.o \

		drm_file.o drm_gem.o drm_ioctl.o \

		drm_drv.o \

include/drm/drm_print.h

+12 −0
Original line number Diff line number Diff line
@@ -384,8 +384,14 @@ void __drm_dev_dbg(const struct device *dev, enum drm_debug_category category, 
	}								\

})



#if !defined(CONFIG_DRM_USE_DYNAMIC_DEBUG)

#define drm_dev_dbg(dev, cat, fmt, ...)				\

	__drm_dev_dbg(dev, cat, fmt, ##__VA_ARGS__)

#else

#define drm_dev_dbg(dev, cat, fmt, ...)				\

	_dynamic_func_call_no_desc(fmt, __drm_dev_dbg,			\

				   dev, cat, fmt, ##__VA_ARGS__)

#endif



/**

 * DRM_DEV_DEBUG() - Debug output for generic drm code
@@ -492,7 +498,13 @@ void ___drm_dbg(enum drm_debug_category category, const char *format, ...); 
__printf(1, 2)

void __drm_err(const char *format, ...);



#if !defined(CONFIG_DRM_USE_DYNAMIC_DEBUG)

#define __drm_dbg(fmt, ...)		___drm_dbg(fmt, ##__VA_ARGS__)

#else

#define __drm_dbg(cat, fmt, ...)					\

	_dynamic_func_call_no_desc(fmt, ___drm_dbg,			\

				   cat, fmt, ##__VA_ARGS__)

#endif



/* Macros to make printk easier */