diff options
Diffstat (limited to 'lib/Kconfig.debug')
| -rw-r--r-- | lib/Kconfig.debug | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index aa81d2848448..31d784dd80d0 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -807,6 +807,61 @@ menuconfig BUILD_DOCSRC Say N if you are unsure. +config DYNAMIC_PRINTK_DEBUG + bool "Enable dynamic printk() call support" + default n + depends on PRINTK + select PRINTK_DEBUG + help + + Compiles debug level messages into the kernel, which would not + otherwise be available at runtime. These messages can then be + enabled/disabled on a per module basis. 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%. + + Usage: + + Dynamic debugging is controlled by the debugfs file, + dynamic_printk/modules. This file contains a list of the modules that + can be enabled. The format of the file is the module name, followed + by a set of flags that can be enabled. The first flag is always the + 'enabled' flag. For example: + + <module_name> <enabled=0/1> + . + . + . + + <module_name> : Name of the module in which the debug call resides + <enabled=0/1> : whether the messages are enabled or not + + From a live system: + + snd_hda_intel enabled=0 + fixup enabled=0 + driver enabled=0 + + Enable a module: + + $echo "set enabled=1 <module_name>" > dynamic_printk/modules + + Disable a module: + + $echo "set enabled=0 <module_name>" > dynamic_printk/modules + + Enable all modules: + + $echo "set enabled=1 all" > dynamic_printk/modules + + Disable all modules: + + $echo "set enabled=0 all" > dynamic_printk/modules + + Finally, passing "dynamic_printk" at the command line enables + debugging for all modules. This mode can be turned off via the above + disable command. + source "samples/Kconfig" source "lib/Kconfig.kgdb" |