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| author | Jim Cromie <jim.cromie@gmail.com> | 2012-04-27 14:30:41 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-04-30 16:26:30 -0400 |
| commit | 29e36c9ffb696ed8d73e1aee713d483ec74a9a43 (patch) | |
| tree | 1cb91235091fa9d750fd56753f6b4ffd6701ca0d /lib/Kconfig.debug | |
| parent | 8e59b5cfb9a6f43753236b554d785e8efca62db7 (diff) | |
| download | lwn-29e36c9ffb696ed8d73e1aee713d483ec74a9a43.tar.gz lwn-29e36c9ffb696ed8d73e1aee713d483ec74a9a43.zip | |
dynamic_debug: update Documentation/*, Kconfig.debug
In dynamic-debug-howto.txt:
- add section: Debug Messages at Module Initialization Time
- update flags indicators in example outputs to include '='
- make flags descriptions tabular
- add item on '_' flag-char
- add dyndbg, boot-args examples
- rewrap some paragraphs with long lines
In Kconfig.debug, note that compiling with -DDEBUG enables all
pr_debug()s in that code.
In kernel-parameters.txt, add dyndbg and module.dyndbg items,
and deprecate ddebug_query.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib/Kconfig.debug')
| -rw-r--r-- | lib/Kconfig.debug | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 6777153f18f3..ef8192bc0c33 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1205,8 +1205,13 @@ config DYNAMIC_DEBUG otherwise be available at runtime. These messages can then be enabled/disabled based on various levels of scope - per source file, function, module, format string, and line number. This mechanism - implicitly enables all pr_debug() and dev_dbg() calls. The impact of - this compile option is a larger kernel text size of about 2%. + implicitly compiles in all pr_debug() and dev_dbg() calls, which + enlarges the kernel text size by about 2%. + + If a source file is compiled with DEBUG flag set, any + pr_debug() calls in it are enabled by default, but can be + disabled at runtime as below. Note that DEBUG flag is + turned on by many CONFIG_*DEBUG* options. Usage: @@ -1223,16 +1228,16 @@ config DYNAMIC_DEBUG lineno : line number of the debug statement module : module that contains the debug statement function : function that contains the debug statement - flags : 'p' means the line is turned 'on' for printing + flags : '=p' means the line is turned 'on' for printing format : the format used for the debug statement From a live system: nullarbor:~ # cat <debugfs>/dynamic_debug/control # filename:lineno [module]function flags format - fs/aio.c:222 [aio]__put_ioctx - "__put_ioctx:\040freeing\040%p\012" - fs/aio.c:248 [aio]ioctx_alloc - "ENOMEM:\040nr_events\040too\040high\012" - fs/aio.c:1770 [aio]sys_io_cancel - "calling\040cancel\012" + fs/aio.c:222 [aio]__put_ioctx =_ "__put_ioctx:\040freeing\040%p\012" + fs/aio.c:248 [aio]ioctx_alloc =_ "ENOMEM:\040nr_events\040too\040high\012" + fs/aio.c:1770 [aio]sys_io_cancel =_ "calling\040cancel\012" Example usage: |