On Thu, 6 Jun 2013, Joe Perches wrote:
How useful really is it to be able to limit the amount of debugging messages at runtime? Does anybody ever actually adjust the "debug" module parameter?
When it's a bitmask, yes. It then becomes similar to ethtool.
But it isn't a bitmask; it's just a level. From sound/core/misc.c:__snd_printk():
#ifdef CONFIG_SND_DEBUG if (debug < level) return; #endif
Since I have no intention of making it a bitmask at the moment, I will presume your answer really means "No".
In my opinion, this is not worth the extra space required. Virtually all the benefit of different debugging levels can be obtained by defining different symbols at compile time, such as CONFIG_SND_DEBUG and CONFIG_SND_VERBOSE_DEBUG.
I think the whole verbosity thing should be done at runtime via pr_debug and classifications by type via bitmasks at compile-time instead of the silliness of something like CONFIG_SND_DEBUG_VERBOSITY.
The appeal of this approach is understandable. But it is a whole different project from the conversion I'm considering for now.
Does anybody really need a third level?
Hard to say. There are several additional "private" debugging level controls for sound/...
Then they can remain private. Takashi asked me not to change the existing Kconfig options, and I won't.
Alan Stern