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: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index dc2c609..81ed832 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -97,26 +97,24 @@
}
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;
+ va_start(args, format);
+ vaf.fmt = format;
+ vaf.va = &args;
- if (function_name)
- printk(KERN_DEBUG "[%s:%s], %pV", prefix,
- function_name, &vaf);
- else
- printk(KERN_DEBUG "%pV", &vaf);
- va_end(args);
- }
+ if (function_name)
+ printk(KERN_DEBUG "[%s:%s], %pV", prefix,
+ function_name, &vaf);
+ else
+ printk(KERN_DEBUG "%pV", &vaf);
+
+ va_end(args);
}
EXPORT_SYMBOL(drm_ut_debug_printk);