[PATCH v2 2/2] drm/print: document DRM_ logging functions

[Daniel Vetter]

On Tue, Jan 07, 2020 at 07:17:52PM +0100, Sam Ravnborg wrote:
> Hi Daniel.
> 
> > > + * Logging when a &device * is available, but no &drm_device *
> > > + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > + *
> > > + * DRM/Drivers can use the following functions for logging when there is a
> > > + * struct device * available.
> > > + * The logging functions share the same prototype:
> > 
> > I'd replace the entire block with a "This stuff is deprecated" warning. We
> > have at least a corresponding todo.rst entry.
> 
> We have many situations where no drm_device is available.
> At least when you a buried in drm_panel patches.
> 
> So it is either DRM_DEV_ERROR() or drv_err().
> Which is why I have pushed for nicer drm_ variants of these...

Huh, drm_panel indeed has no drm_device. And I guess we don't have a
convenient excuse to add it ...

> The todo entry only covers the nice new macros that Jani added
> where we have a drm_device.

I wonder whether for those cases we shouldn't just directly use the
various dev_* macros?
-Daniel

> 
> 	Sam
> 
> 
> 
> > -Daniel
> > 
> > > + *
> > > + * .. code-block:: c
> > > + *
> > > + *   void DRM_xxx(struct device *, char * fmt, ...)
> > > + *
> > > + * .. code-block:: none
> > > + *
> > > + *   # Plain logging
> > > + *   DRM_DEV_INFO(dev, fmt, ...)
> > > + *   DRM_DEV_ERROR(dev, fmt, ...)
> > > + *
> > > + *   # Log only once
> > > + *   DRM_DEV_INFO_ONCE(dev, fmt, ...)
> > > + *
> > > + *   # Ratelimited - do not flood the logs
> > > + *   DRM_DEV_DEBUG_RATELIMITED(dev, fmt, ...)
> > > + *   DRM_DEV_DEBUG_DRIVER_RATELIMITED(dev, fmt, ...)
> > > + *   DRM_DEV_DEBUG_KMS_RATELIMITED(dev, fmt, ...)
> > > + *   DRM_DEV_DEBUG_PRIME_RATELIMITED(dev, fmt, ...)
> > > + *   DRM_DEV_ERROR_RATELIMITED(dev, fmt, ...)
> > > + *
> > > + *   # Logging with a specific category
> > > + *   DRM_DEV_DEBUG(dev, fmt, ...)		# Logged as CORE
> > > + *   DRM_DEV_DEBUG_DRIVER(dev, fmt, ...)
> > > + *   DRM_DEV_DEBUG_KMS(dev, fmt, ...)
> > > + *   DRM_DEV_DEBUG_PRIME(dev, fmt, ...)
> > > + *   DRM_DEV_DEBUG_ATOMIC(dev, fmt, ...)
> > > + *   DRM_DEV_DEBUG_VBL(dev, fmt, ...)
> > > + *   DRM_DEV_DEBUG_DP(dev, fmt, ...)
> > > + *
> > > + * Logging when no &device * nor &drm_device * is available
> > > + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > + *
> > > + * DRM/Drivers can use the following functions for logging when there is no
> > > + * extra info associated to the logging.
> > > + * The logging functions share the same prototype:
> > > + *
> > > + * .. code-block:: c
> > > + *
> > > + *   void DRM_xxx(char * fmt, ...)
> > > + *
> > > + * .. code-block:: none
> > > + *
> > > + *   # Plain logging
> > > + *   DRM_INFO(fmt, ...)
> > > + *   DRM_NOTE(fmt, ...)
> > > + *   DRM_WARN(fmt, ...)
> > > + *   DRM_ERROR(fmt, ...)
> > > + *
> > > + *   # Log only once
> > > + *   DRM_INFO_ONCE(fmt, ...)
> > > + *   DRM_NOTE_ONCE(fmt, ...)
> > > + *   DRM_WARN_ONCE(fmt, ...)
> > > + *
> > > + *   # Ratelimited - do not flood the logs
> > > + *   DRM_DEBUG_RATELIMITED(fmt, ...)
> > > + *   DRM_DEBUG_DRIVER_RATELIMITED(fmt, ...)
> > > + *   DRM_DEBUG_KMS_RATELIMITED(fmt, ...)
> > > + *   DRM_DEBUG_PRIME_RATELIMITED(fmt, ...)
> > > + *   DRM_ERROR_RATELIMITED(fmt, ...)
> > > + *
> > > + *   # Logging with a specific category
> > > + *   DRM_DEBUG(fmt, ...)		# Logged as CORE
> > > + *   DRM_DEBUG_DRIVER(fmt, ...)
> > > + *   DRM_DEBUG_KMS(fmt, ...)
> > > + *   DRM_DEBUG_PRIME(fmt, ...)
> > > + *   DRM_DEBUG_ATOMIC(fmt, ...)
> > > + *   DRM_DEBUG_VBL(fmt, ...)
> > > + *   DRM_DEBUG_LEASE(fmt, ...)
> > > + *   DRM_DEBUG_DP(fmt, ...)
> > >   */
> > >  
> > >  /**
> > > @@ -399,7 +475,7 @@ __printf(3, 4)
> > >  void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
> > >  		 const char *format, ...);
> > >  
> > > -/**
> > > +/*
> > >   * Error output.
> > >   *
> > >   * @dev: device pointer
> > > @@ -408,7 +484,7 @@ void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
> > >  #define DRM_DEV_ERROR(dev, fmt, ...)					\
> > >  	drm_dev_printk(dev, KERN_ERR, "*ERROR* " fmt, ##__VA_ARGS__)
> > >  
> > > -/**
> > > +/*
> > >   * Rate limited error output.  Like DRM_ERROR() but won't flood the log.
> > >   *
> > >   * @dev: device pointer
> > > @@ -436,7 +512,7 @@ void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
> > >  	}								\
> > >  })
> > >  
> > > -/**
> > > +/*
> > >   * Debug output.
> > >   *
> > >   * @dev: device pointer
> > > @@ -466,7 +542,7 @@ void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
> > >  		drm_dev_dbg(dev, category, fmt, ##__VA_ARGS__);		\
> > >  })
> > >  
> > > -/**
> > > +/*
> > >   * Rate limited debug output. Like DRM_DEBUG() but won't flood the log.
> > >   *
> > >   * @dev: device pointer
> > > -- 
> > > 2.20.1
> > > 
> > 
> > -- 
> > Daniel Vetter
> > Software Engineer, Intel Corporation
> > http://blog.ffwll.ch

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch