diff options
| author | David Brownell <david-b@pacbell.net> | 2007-07-13 16:32:09 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-07-18 15:49:50 -0700 |
| commit | 6b09448ab81e90e59c09cfbc6d0d612dc84a2b1d (patch) | |
| tree | 6c2fc89767cb438dc168dc867c9931b5425c5f46 /Documentation/CodingStyle | |
| parent | aebdc3b450a3febf7d7d00cd2235509055ec7082 (diff) | |
| download | lwn-6b09448ab81e90e59c09cfbc6d0d612dc84a2b1d.tar.gz lwn-6b09448ab81e90e59c09cfbc6d0d612dc84a2b1d.zip | |
dev_vdbg() documentation
Update CodingStyle to talk about "-DDEBUG" message conventions and the
new "-DVERBOSE_DEBUG" convention.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'Documentation/CodingStyle')
| -rw-r--r-- | Documentation/CodingStyle | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index a667eb1fc26e..7f1730f1a1ae 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -633,12 +633,27 @@ covers RTL which is used frequently with assembly language in the kernel. Kernel developers like to be seen as literate. Do mind the spelling of kernel messages to make a good impression. Do not use crippled -words like "dont" and use "do not" or "don't" instead. +words like "dont"; use "do not" or "don't" instead. Make the messages +concise, clear, and unambiguous. Kernel messages do not have to be terminated with a period. Printing numbers in parentheses (%d) adds no value and should be avoided. +There are a number of driver model diagnostic macros in <linux/device.h> +which you should use to make sure messages are matched to the right device +and driver, and are tagged with the right level: dev_err(), dev_warn(), +dev_info(), and so forth. For messages that aren't associated with a +particular device, <linux/kernel.h> defines pr_debug() and pr_info(). + +Coming up with good debugging messages can be quite a challenge; and once +you have them, they can be a huge help for remote troubleshooting. Such +messages should be compiled out when the DEBUG symbol is not defined (that +is, by default they are not included). When you use dev_dbg() or pr_debug(), +that's automatic. Many subsystems have Kconfig options to turn on -DDEBUG. +A related convention uses VERBOSE_DEBUG to add dev_vdbg() messages to the +ones already enabled by DEBUG. + Chapter 14: Allocating memory @@ -790,4 +805,5 @@ Kernel CodingStyle, by greg@kroah.com at OLS 2002: http://www.kroah.com/linux/talks/ols_2002_kernel_codingstyle_talk/html/ -- -Last updated on 2006-December-06. +Last updated on 2007-July-13. + |