aboutsummaryrefslogtreecommitdiffstats
path: root/lib/Kconfig.debug
diff options
context:
space:
mode:
Diffstat (limited to 'lib/Kconfig.debug')
-rw-r--r--lib/Kconfig.debug42
1 files changed, 30 insertions, 12 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 6777153f18f3..a42d3ae39648 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -3,12 +3,16 @@ config PRINTK_TIME
3 bool "Show timing information on printks" 3 bool "Show timing information on printks"
4 depends on PRINTK 4 depends on PRINTK
5 help 5 help
6 Selecting this option causes timing information to be 6 Selecting this option causes time stamps of the printk()
7 included in printk output. This allows you to measure 7 messages to be added to the output of the syslog() system
8 the interval between kernel operations, including bootup 8 call and at the console.
9 operations. This is useful for identifying long delays 9
10 in kernel startup. Or add printk.time=1 at boot-time. 10 The timestamp is always recorded internally, and exported
11 See Documentation/kernel-parameters.txt 11 to /dev/kmsg. This flag just specifies if the timestamp should
12 be included, not that the timestamp is recorded.
13
14 The behavior is also controlled by the kernel command line
15 parameter printk.time=1. See Documentation/kernel-parameters.txt
12 16
13config DEFAULT_MESSAGE_LOGLEVEL 17config DEFAULT_MESSAGE_LOGLEVEL
14 int "Default message log level (1-7)" 18 int "Default message log level (1-7)"
@@ -70,6 +74,15 @@ config STRIP_ASM_SYMS
70 that look like '.Lxxx') so they don't pollute the output of 74 that look like '.Lxxx') so they don't pollute the output of
71 get_wchan() and suchlike. 75 get_wchan() and suchlike.
72 76
77config READABLE_ASM
78 bool "Generate readable assembler code"
79 depends on DEBUG_KERNEL
80 help
81 Disable some compiler optimizations that tend to generate human unreadable
82 assembler output. This may make the kernel slightly slower, but it helps
83 to keep kernel developers who have to stare a lot at assembler listings
84 sane.
85
73config UNUSED_SYMBOLS 86config UNUSED_SYMBOLS
74 bool "Enable unused/obsolete exported symbols" 87 bool "Enable unused/obsolete exported symbols"
75 default y if X86 88 default y if X86
@@ -1205,8 +1218,13 @@ config DYNAMIC_DEBUG
1205 otherwise be available at runtime. These messages can then be 1218 otherwise be available at runtime. These messages can then be
1206 enabled/disabled based on various levels of scope - per source file, 1219 enabled/disabled based on various levels of scope - per source file,
1207 function, module, format string, and line number. This mechanism 1220 function, module, format string, and line number. This mechanism
1208 implicitly enables all pr_debug() and dev_dbg() calls. The impact of 1221 implicitly compiles in all pr_debug() and dev_dbg() calls, which
1209 this compile option is a larger kernel text size of about 2%. 1222 enlarges the kernel text size by about 2%.
1223
1224 If a source file is compiled with DEBUG flag set, any
1225 pr_debug() calls in it are enabled by default, but can be
1226 disabled at runtime as below. Note that DEBUG flag is
1227 turned on by many CONFIG_*DEBUG* options.
1210 1228
1211 Usage: 1229 Usage:
1212 1230
@@ -1223,16 +1241,16 @@ config DYNAMIC_DEBUG
1223 lineno : line number of the debug statement 1241 lineno : line number of the debug statement
1224 module : module that contains the debug statement 1242 module : module that contains the debug statement
1225 function : function that contains the debug statement 1243 function : function that contains the debug statement
1226 flags : 'p' means the line is turned 'on' for printing 1244 flags : '=p' means the line is turned 'on' for printing
1227 format : the format used for the debug statement 1245 format : the format used for the debug statement
1228 1246
1229 From a live system: 1247 From a live system:
1230 1248
1231 nullarbor:~ # cat <debugfs>/dynamic_debug/control 1249 nullarbor:~ # cat <debugfs>/dynamic_debug/control
1232 # filename:lineno [module]function flags format 1250 # filename:lineno [module]function flags format
1233 fs/aio.c:222 [aio]__put_ioctx - "__put_ioctx:\040freeing\040%p\012" 1251 fs/aio.c:222 [aio]__put_ioctx =_ "__put_ioctx:\040freeing\040%p\012"
1234 fs/aio.c:248 [aio]ioctx_alloc - "ENOMEM:\040nr_events\040too\040high\012" 1252 fs/aio.c:248 [aio]ioctx_alloc =_ "ENOMEM:\040nr_events\040too\040high\012"
1235 fs/aio.c:1770 [aio]sys_io_cancel - "calling\040cancel\012" 1253 fs/aio.c:1770 [aio]sys_io_cancel =_ "calling\040cancel\012"
1236 1254
1237 Example usage: 1255 Example usage:
1238 1256