+config BUILD_DOCSRC
+ bool "Build targets in Documentation/ tree"
+ depends on HEADERS_CHECK
+ help
+ This option attempts to build objects from the source files in the
+ kernel Documentation/ tree.
+
+ Say N if you are unsure.
+
+config DYNAMIC_DEBUG
+ bool "Enable dynamic printk() support"
+ default n
+ depends on PRINTK
+ depends on DEBUG_FS
+ help
+
+ Compiles debug level messages into the kernel, which would not
+ 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%.
+
+ Usage:
+
+ Dynamic debugging is controlled via the 'dynamic_debug/ddebug' file,
+ which is contained in the 'debugfs' filesystem. Thus, the debugfs
+ filesystem must first be mounted before making use of this feature.
+ We refer the control file as: <debugfs>/dynamic_debug/ddebug. This
+ file contains a list of the debug statements that can be enabled. The
+ format for each line of the file is:
+
+ filename:lineno [module]function flags format
+
+ filename : source file of the debug statement
+ 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
+ format : the format used for the debug statement
+
+ From a live system:
+
+ nullarbor:~ # cat <debugfs>/dynamic_debug/ddebug
+ # 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"
+
+ Example usage:
+
+ // enable the message at line 1603 of file svcsock.c
+ nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' >
+ <debugfs>/dynamic_debug/ddebug
+
+ // enable all the messages in file svcsock.c
+ nullarbor:~ # echo -n 'file svcsock.c +p' >
+ <debugfs>/dynamic_debug/ddebug
+
+ // enable all the messages in the NFS server module
+ nullarbor:~ # echo -n 'module nfsd +p' >
+ <debugfs>/dynamic_debug/ddebug
+
+ // enable all 12 messages in the function svc_process()
+ nullarbor:~ # echo -n 'func svc_process +p' >
+ <debugfs>/dynamic_debug/ddebug
+
+ // disable all 12 messages in the function svc_process()
+ nullarbor:~ # echo -n 'func svc_process -p' >
+ <debugfs>/dynamic_debug/ddebug
+
+ See Documentation/dynamic-debug-howto.txt for additional information.
+
+config DMA_API_DEBUG
+ bool "Enable debugging of DMA-API usage"
+ depends on HAVE_DMA_API_DEBUG
+ help
+ Enable this option to debug the use of the DMA API by device drivers.
+ With this option you will be able to detect common bugs in device
+ drivers like double-freeing of DMA mappings or freeing mappings that
+ were never allocated.
+ This option causes a performance degredation. Use only if you want
+ to debug device drivers. If unsure, say N.
+