Commit a73d4e91 authored by Lespiau, Damien's avatar Lespiau, Damien Committed by Dave Airlie
Browse files

drm: Pull the test on drm_debug in the logging macros 



In the logging code, we are currently checking is we need to output in
drm_ut_debug_printk(). This is too late. The problem is that when we write
something like:

    DRM_DEBUG_DRIVER("ELD on [CONNECTOR:%d:%s], [ENCODER:%d:%s]\n",
                     connector->base.id,
                     drm_get_connector_name(connector),
                     connector->encoder->base.id,
                     drm_get_encoder_name(connector->encoder));

We start by evaluating the arguments (so call drm_get_connector_name() and
drm_get_connector_name()) before ending up in drm_ut_debug_printk() which will
then does nothing.

This means we execute a lot of instructions (drm_get_connector_name(), in turn,
calls snprintf() for example) to happily discard them in the normal case,
drm.debug=0.

So, let's put the test on drm_debug earlier, in the macros themselves.
Sprinkle an unlikely() as well for good measure.

Signed-off-by: default avatarDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
parent 8fa6a9e7

drivers/gpu/drm/drm_stub.c

+12 −14
Original line number Diff line number Diff line
@@ -97,15 +97,13 @@ int drm_err(const char *func, const char *format, ...) 
}

EXPORT_SYMBOL(drm_err);



void drm_ut_debug_printk(unsigned int request_level,

			 const char *prefix,

void drm_ut_debug_printk(const char *prefix,

			 const char *function_name,

			 const char *format, ...)

{

	struct va_format vaf;

	va_list args;



	if (drm_debug & request_level) {

	va_start(args, format);

	vaf.fmt = format;

	vaf.va = &args;
@@ -115,9 +113,9 @@ void drm_ut_debug_printk(unsigned int request_level, 
		       function_name, &vaf);

	else

		printk(KERN_DEBUG "%pV", &vaf);



	va_end(args);

}

}

EXPORT_SYMBOL(drm_ut_debug_printk);



struct drm_master *drm_master_create(struct drm_minor *minor)

include/drm/drmP.h

+15 −12
Original line number Diff line number Diff line
@@ -121,9 +121,8 @@ struct videomode; 
#define DRM_UT_KMS		0x04

#define DRM_UT_PRIME		0x08



extern __printf(4, 5)

void drm_ut_debug_printk(unsigned int request_level,

			 const char *prefix,

extern __printf(3, 4)

void drm_ut_debug_printk(const char *prefix,

			 const char *function_name,

			 const char *format, ...);

extern __printf(2, 3)
@@ -209,24 +208,28 @@ int drm_err(const char *func, const char *format, ...); 
#if DRM_DEBUG_CODE

#define DRM_DEBUG(fmt, args...)						\

	do {								\

		drm_ut_debug_printk(DRM_UT_CORE, DRM_NAME, 		\

					__func__, fmt, ##args);		\

		if (unlikely(drm_debug & DRM_UT_CORE))			\

			drm_ut_debug_printk(DRM_NAME, __func__,		\

					    fmt, ##args);		\

	} while (0)



#define DRM_DEBUG_DRIVER(fmt, args...)					\

	do {								\

		drm_ut_debug_printk(DRM_UT_DRIVER, DRM_NAME,		\

					__func__, fmt, ##args);		\

		if (unlikely(drm_debug & DRM_UT_DRIVER))		\

			drm_ut_debug_printk(DRM_NAME, __func__,		\

					    fmt, ##args);		\

	} while (0)

#define DRM_DEBUG_KMS(fmt, args...)					\

	do {								\

		drm_ut_debug_printk(DRM_UT_KMS, DRM_NAME, 		\

					 __func__, fmt, ##args);	\

		if (unlikely(drm_debug & DRM_UT_KMS))			\

			drm_ut_debug_printk(DRM_NAME, __func__,		\

					    fmt, ##args);		\

	} while (0)

#define DRM_DEBUG_PRIME(fmt, args...)					\

	do {								\

		drm_ut_debug_printk(DRM_UT_PRIME, DRM_NAME,		\

					__func__, fmt, ##args);		\

		if (unlikely(drm_debug & DRM_UT_PRIME))			\

			drm_ut_debug_printk(DRM_NAME, __func__,		\

					    fmt, ##args);		\

	} while (0)

#else

#define DRM_DEBUG_DRIVER(fmt, args...) do { } while (0)

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