Commit 625fdcaa6d2a3db6a922bbd833450424e906111c
Committed by
Ingo Molnar
1 parent
f24645a991
Exists in
master
and in
7 other branches
latencytop: Fix kconfig dependency warnings
warning: (LATENCYTOP && HAVE_LATENCYTOP_SUPPORT) selects SCHED_DEBUG which has unmet direct dependencies (DEBUG_KERNEL && PROC_FS) warning: (LATENCYTOP && HAVE_LATENCYTOP_SUPPORT) selects SCHEDSTATS which has unmet direct dependencies (DEBUG_KERNEL && PROC_FS) Add depends on STACKTRACE_SUPPORT for 'select STACKTRACE'. Add depends on PROC_FS since that is where the output goes. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20100812123121.a7c99cde.randy.dunlap@oracle.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Showing 1 changed file with 4 additions and 1 deletions Inline Diff
lib/Kconfig.debug
1 | 1 | ||
2 | config PRINTK_TIME | 2 | 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 timing information to be |
7 | included in printk output. This allows you to measure | 7 | included in printk output. This allows you to measure |
8 | the interval between kernel operations, including bootup | 8 | the interval between kernel operations, including bootup |
9 | operations. This is useful for identifying long delays | 9 | operations. This is useful for identifying long delays |
10 | in kernel startup. | 10 | in kernel startup. |
11 | 11 | ||
12 | config ENABLE_WARN_DEPRECATED | 12 | config ENABLE_WARN_DEPRECATED |
13 | bool "Enable __deprecated logic" | 13 | bool "Enable __deprecated logic" |
14 | default y | 14 | default y |
15 | help | 15 | help |
16 | Enable the __deprecated logic in the kernel build. | 16 | Enable the __deprecated logic in the kernel build. |
17 | Disable this to suppress the "warning: 'foo' is deprecated | 17 | Disable this to suppress the "warning: 'foo' is deprecated |
18 | (declared at kernel/power/somefile.c:1234)" messages. | 18 | (declared at kernel/power/somefile.c:1234)" messages. |
19 | 19 | ||
20 | config ENABLE_MUST_CHECK | 20 | config ENABLE_MUST_CHECK |
21 | bool "Enable __must_check logic" | 21 | bool "Enable __must_check logic" |
22 | default y | 22 | default y |
23 | help | 23 | help |
24 | Enable the __must_check logic in the kernel build. Disable this to | 24 | Enable the __must_check logic in the kernel build. Disable this to |
25 | suppress the "warning: ignoring return value of 'foo', declared with | 25 | suppress the "warning: ignoring return value of 'foo', declared with |
26 | attribute warn_unused_result" messages. | 26 | attribute warn_unused_result" messages. |
27 | 27 | ||
28 | config FRAME_WARN | 28 | config FRAME_WARN |
29 | int "Warn for stack frames larger than (needs gcc 4.4)" | 29 | int "Warn for stack frames larger than (needs gcc 4.4)" |
30 | range 0 8192 | 30 | range 0 8192 |
31 | default 1024 if !64BIT | 31 | default 1024 if !64BIT |
32 | default 2048 if 64BIT | 32 | default 2048 if 64BIT |
33 | help | 33 | help |
34 | Tell gcc to warn at build time for stack frames larger than this. | 34 | Tell gcc to warn at build time for stack frames larger than this. |
35 | Setting this too low will cause a lot of warnings. | 35 | Setting this too low will cause a lot of warnings. |
36 | Setting it to 0 disables the warning. | 36 | Setting it to 0 disables the warning. |
37 | Requires gcc 4.4 | 37 | Requires gcc 4.4 |
38 | 38 | ||
39 | config MAGIC_SYSRQ | 39 | config MAGIC_SYSRQ |
40 | bool "Magic SysRq key" | 40 | bool "Magic SysRq key" |
41 | depends on !UML | 41 | depends on !UML |
42 | help | 42 | help |
43 | If you say Y here, you will have some control over the system even | 43 | If you say Y here, you will have some control over the system even |
44 | if the system crashes for example during kernel debugging (e.g., you | 44 | if the system crashes for example during kernel debugging (e.g., you |
45 | will be able to flush the buffer cache to disk, reboot the system | 45 | will be able to flush the buffer cache to disk, reboot the system |
46 | immediately or dump some status information). This is accomplished | 46 | immediately or dump some status information). This is accomplished |
47 | by pressing various keys while holding SysRq (Alt+PrintScreen). It | 47 | by pressing various keys while holding SysRq (Alt+PrintScreen). It |
48 | also works on a serial console (on PC hardware at least), if you | 48 | also works on a serial console (on PC hardware at least), if you |
49 | send a BREAK and then within 5 seconds a command keypress. The | 49 | send a BREAK and then within 5 seconds a command keypress. The |
50 | keys are documented in <file:Documentation/sysrq.txt>. Don't say Y | 50 | keys are documented in <file:Documentation/sysrq.txt>. Don't say Y |
51 | unless you really know what this hack does. | 51 | unless you really know what this hack does. |
52 | 52 | ||
53 | config STRIP_ASM_SYMS | 53 | config STRIP_ASM_SYMS |
54 | bool "Strip assembler-generated symbols during link" | 54 | bool "Strip assembler-generated symbols during link" |
55 | default n | 55 | default n |
56 | help | 56 | help |
57 | Strip internal assembler-generated symbols during a link (symbols | 57 | Strip internal assembler-generated symbols during a link (symbols |
58 | that look like '.Lxxx') so they don't pollute the output of | 58 | that look like '.Lxxx') so they don't pollute the output of |
59 | get_wchan() and suchlike. | 59 | get_wchan() and suchlike. |
60 | 60 | ||
61 | config UNUSED_SYMBOLS | 61 | config UNUSED_SYMBOLS |
62 | bool "Enable unused/obsolete exported symbols" | 62 | bool "Enable unused/obsolete exported symbols" |
63 | default y if X86 | 63 | default y if X86 |
64 | help | 64 | help |
65 | Unused but exported symbols make the kernel needlessly bigger. For | 65 | Unused but exported symbols make the kernel needlessly bigger. For |
66 | that reason most of these unused exports will soon be removed. This | 66 | that reason most of these unused exports will soon be removed. This |
67 | option is provided temporarily to provide a transition period in case | 67 | option is provided temporarily to provide a transition period in case |
68 | some external kernel module needs one of these symbols anyway. If you | 68 | some external kernel module needs one of these symbols anyway. If you |
69 | encounter such a case in your module, consider if you are actually | 69 | encounter such a case in your module, consider if you are actually |
70 | using the right API. (rationale: since nobody in the kernel is using | 70 | using the right API. (rationale: since nobody in the kernel is using |
71 | this in a module, there is a pretty good chance it's actually the | 71 | this in a module, there is a pretty good chance it's actually the |
72 | wrong interface to use). If you really need the symbol, please send a | 72 | wrong interface to use). If you really need the symbol, please send a |
73 | mail to the linux kernel mailing list mentioning the symbol and why | 73 | mail to the linux kernel mailing list mentioning the symbol and why |
74 | you really need it, and what the merge plan to the mainline kernel for | 74 | you really need it, and what the merge plan to the mainline kernel for |
75 | your module is. | 75 | your module is. |
76 | 76 | ||
77 | config DEBUG_FS | 77 | config DEBUG_FS |
78 | bool "Debug Filesystem" | 78 | bool "Debug Filesystem" |
79 | help | 79 | help |
80 | debugfs is a virtual file system that kernel developers use to put | 80 | debugfs is a virtual file system that kernel developers use to put |
81 | debugging files into. Enable this option to be able to read and | 81 | debugging files into. Enable this option to be able to read and |
82 | write to these files. | 82 | write to these files. |
83 | 83 | ||
84 | For detailed documentation on the debugfs API, see | 84 | For detailed documentation on the debugfs API, see |
85 | Documentation/DocBook/filesystems. | 85 | Documentation/DocBook/filesystems. |
86 | 86 | ||
87 | If unsure, say N. | 87 | If unsure, say N. |
88 | 88 | ||
89 | config HEADERS_CHECK | 89 | config HEADERS_CHECK |
90 | bool "Run 'make headers_check' when building vmlinux" | 90 | bool "Run 'make headers_check' when building vmlinux" |
91 | depends on !UML | 91 | depends on !UML |
92 | help | 92 | help |
93 | This option will extract the user-visible kernel headers whenever | 93 | This option will extract the user-visible kernel headers whenever |
94 | building the kernel, and will run basic sanity checks on them to | 94 | building the kernel, and will run basic sanity checks on them to |
95 | ensure that exported files do not attempt to include files which | 95 | ensure that exported files do not attempt to include files which |
96 | were not exported, etc. | 96 | were not exported, etc. |
97 | 97 | ||
98 | If you're making modifications to header files which are | 98 | If you're making modifications to header files which are |
99 | relevant for userspace, say 'Y', and check the headers | 99 | relevant for userspace, say 'Y', and check the headers |
100 | exported to $(INSTALL_HDR_PATH) (usually 'usr/include' in | 100 | exported to $(INSTALL_HDR_PATH) (usually 'usr/include' in |
101 | your build tree), to make sure they're suitable. | 101 | your build tree), to make sure they're suitable. |
102 | 102 | ||
103 | config DEBUG_SECTION_MISMATCH | 103 | config DEBUG_SECTION_MISMATCH |
104 | bool "Enable full Section mismatch analysis" | 104 | bool "Enable full Section mismatch analysis" |
105 | depends on UNDEFINED || (BLACKFIN) | 105 | depends on UNDEFINED || (BLACKFIN) |
106 | default y | 106 | default y |
107 | # This option is on purpose disabled for now. | 107 | # This option is on purpose disabled for now. |
108 | # It will be enabled when we are down to a reasonable number | 108 | # It will be enabled when we are down to a reasonable number |
109 | # of section mismatch warnings (< 10 for an allyesconfig build) | 109 | # of section mismatch warnings (< 10 for an allyesconfig build) |
110 | help | 110 | help |
111 | The section mismatch analysis checks if there are illegal | 111 | The section mismatch analysis checks if there are illegal |
112 | references from one section to another section. | 112 | references from one section to another section. |
113 | Linux will during link or during runtime drop some sections | 113 | Linux will during link or during runtime drop some sections |
114 | and any use of code/data previously in these sections will | 114 | and any use of code/data previously in these sections will |
115 | most likely result in an oops. | 115 | most likely result in an oops. |
116 | In the code functions and variables are annotated with | 116 | In the code functions and variables are annotated with |
117 | __init, __devinit etc. (see full list in include/linux/init.h) | 117 | __init, __devinit etc. (see full list in include/linux/init.h) |
118 | which results in the code/data being placed in specific sections. | 118 | which results in the code/data being placed in specific sections. |
119 | The section mismatch analysis is always done after a full | 119 | The section mismatch analysis is always done after a full |
120 | kernel build but enabling this option will in addition | 120 | kernel build but enabling this option will in addition |
121 | do the following: | 121 | do the following: |
122 | - Add the option -fno-inline-functions-called-once to gcc | 122 | - Add the option -fno-inline-functions-called-once to gcc |
123 | When inlining a function annotated __init in a non-init | 123 | When inlining a function annotated __init in a non-init |
124 | function we would lose the section information and thus | 124 | function we would lose the section information and thus |
125 | the analysis would not catch the illegal reference. | 125 | the analysis would not catch the illegal reference. |
126 | This option tells gcc to inline less but will also | 126 | This option tells gcc to inline less but will also |
127 | result in a larger kernel. | 127 | result in a larger kernel. |
128 | - Run the section mismatch analysis for each module/built-in.o | 128 | - Run the section mismatch analysis for each module/built-in.o |
129 | When we run the section mismatch analysis on vmlinux.o we | 129 | When we run the section mismatch analysis on vmlinux.o we |
130 | lose valueble information about where the mismatch was | 130 | lose valueble information about where the mismatch was |
131 | introduced. | 131 | introduced. |
132 | Running the analysis for each module/built-in.o file | 132 | Running the analysis for each module/built-in.o file |
133 | will tell where the mismatch happens much closer to the | 133 | will tell where the mismatch happens much closer to the |
134 | source. The drawback is that we will report the same | 134 | source. The drawback is that we will report the same |
135 | mismatch at least twice. | 135 | mismatch at least twice. |
136 | - Enable verbose reporting from modpost to help solving | 136 | - Enable verbose reporting from modpost to help solving |
137 | the section mismatches reported. | 137 | the section mismatches reported. |
138 | 138 | ||
139 | config DEBUG_KERNEL | 139 | config DEBUG_KERNEL |
140 | bool "Kernel debugging" | 140 | bool "Kernel debugging" |
141 | help | 141 | help |
142 | Say Y here if you are developing drivers or trying to debug and | 142 | Say Y here if you are developing drivers or trying to debug and |
143 | identify kernel problems. | 143 | identify kernel problems. |
144 | 144 | ||
145 | config DEBUG_SHIRQ | 145 | config DEBUG_SHIRQ |
146 | bool "Debug shared IRQ handlers" | 146 | bool "Debug shared IRQ handlers" |
147 | depends on DEBUG_KERNEL && GENERIC_HARDIRQS | 147 | depends on DEBUG_KERNEL && GENERIC_HARDIRQS |
148 | help | 148 | help |
149 | Enable this to generate a spurious interrupt as soon as a shared | 149 | Enable this to generate a spurious interrupt as soon as a shared |
150 | interrupt handler is registered, and just before one is deregistered. | 150 | interrupt handler is registered, and just before one is deregistered. |
151 | Drivers ought to be able to handle interrupts coming in at those | 151 | Drivers ought to be able to handle interrupts coming in at those |
152 | points; some don't and need to be caught. | 152 | points; some don't and need to be caught. |
153 | 153 | ||
154 | config LOCKUP_DETECTOR | 154 | config LOCKUP_DETECTOR |
155 | bool "Detect Hard and Soft Lockups" | 155 | bool "Detect Hard and Soft Lockups" |
156 | depends on DEBUG_KERNEL && !S390 | 156 | depends on DEBUG_KERNEL && !S390 |
157 | help | 157 | help |
158 | Say Y here to enable the kernel to act as a watchdog to detect | 158 | Say Y here to enable the kernel to act as a watchdog to detect |
159 | hard and soft lockups. | 159 | hard and soft lockups. |
160 | 160 | ||
161 | Softlockups are bugs that cause the kernel to loop in kernel | 161 | Softlockups are bugs that cause the kernel to loop in kernel |
162 | mode for more than 60 seconds, without giving other tasks a | 162 | mode for more than 60 seconds, without giving other tasks a |
163 | chance to run. The current stack trace is displayed upon | 163 | chance to run. The current stack trace is displayed upon |
164 | detection and the system will stay locked up. | 164 | detection and the system will stay locked up. |
165 | 165 | ||
166 | Hardlockups are bugs that cause the CPU to loop in kernel mode | 166 | Hardlockups are bugs that cause the CPU to loop in kernel mode |
167 | for more than 60 seconds, without letting other interrupts have a | 167 | for more than 60 seconds, without letting other interrupts have a |
168 | chance to run. The current stack trace is displayed upon detection | 168 | chance to run. The current stack trace is displayed upon detection |
169 | and the system will stay locked up. | 169 | and the system will stay locked up. |
170 | 170 | ||
171 | The overhead should be minimal. A periodic hrtimer runs to | 171 | The overhead should be minimal. A periodic hrtimer runs to |
172 | generate interrupts and kick the watchdog task every 10-12 seconds. | 172 | generate interrupts and kick the watchdog task every 10-12 seconds. |
173 | An NMI is generated every 60 seconds or so to check for hardlockups. | 173 | An NMI is generated every 60 seconds or so to check for hardlockups. |
174 | 174 | ||
175 | config HARDLOCKUP_DETECTOR | 175 | config HARDLOCKUP_DETECTOR |
176 | def_bool LOCKUP_DETECTOR && PERF_EVENTS && HAVE_PERF_EVENTS_NMI | 176 | def_bool LOCKUP_DETECTOR && PERF_EVENTS && HAVE_PERF_EVENTS_NMI |
177 | 177 | ||
178 | config BOOTPARAM_SOFTLOCKUP_PANIC | 178 | config BOOTPARAM_SOFTLOCKUP_PANIC |
179 | bool "Panic (Reboot) On Soft Lockups" | 179 | bool "Panic (Reboot) On Soft Lockups" |
180 | depends on LOCKUP_DETECTOR | 180 | depends on LOCKUP_DETECTOR |
181 | help | 181 | help |
182 | Say Y here to enable the kernel to panic on "soft lockups", | 182 | Say Y here to enable the kernel to panic on "soft lockups", |
183 | which are bugs that cause the kernel to loop in kernel | 183 | which are bugs that cause the kernel to loop in kernel |
184 | mode for more than 60 seconds, without giving other tasks a | 184 | mode for more than 60 seconds, without giving other tasks a |
185 | chance to run. | 185 | chance to run. |
186 | 186 | ||
187 | The panic can be used in combination with panic_timeout, | 187 | The panic can be used in combination with panic_timeout, |
188 | to cause the system to reboot automatically after a | 188 | to cause the system to reboot automatically after a |
189 | lockup has been detected. This feature is useful for | 189 | lockup has been detected. This feature is useful for |
190 | high-availability systems that have uptime guarantees and | 190 | high-availability systems that have uptime guarantees and |
191 | where a lockup must be resolved ASAP. | 191 | where a lockup must be resolved ASAP. |
192 | 192 | ||
193 | Say N if unsure. | 193 | Say N if unsure. |
194 | 194 | ||
195 | config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE | 195 | config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE |
196 | int | 196 | int |
197 | depends on LOCKUP_DETECTOR | 197 | depends on LOCKUP_DETECTOR |
198 | range 0 1 | 198 | range 0 1 |
199 | default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC | 199 | default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC |
200 | default 1 if BOOTPARAM_SOFTLOCKUP_PANIC | 200 | default 1 if BOOTPARAM_SOFTLOCKUP_PANIC |
201 | 201 | ||
202 | config DETECT_HUNG_TASK | 202 | config DETECT_HUNG_TASK |
203 | bool "Detect Hung Tasks" | 203 | bool "Detect Hung Tasks" |
204 | depends on DEBUG_KERNEL | 204 | depends on DEBUG_KERNEL |
205 | default DETECT_SOFTLOCKUP | 205 | default DETECT_SOFTLOCKUP |
206 | help | 206 | help |
207 | Say Y here to enable the kernel to detect "hung tasks", | 207 | Say Y here to enable the kernel to detect "hung tasks", |
208 | which are bugs that cause the task to be stuck in | 208 | which are bugs that cause the task to be stuck in |
209 | uninterruptible "D" state indefinitiley. | 209 | uninterruptible "D" state indefinitiley. |
210 | 210 | ||
211 | When a hung task is detected, the kernel will print the | 211 | When a hung task is detected, the kernel will print the |
212 | current stack trace (which you should report), but the | 212 | current stack trace (which you should report), but the |
213 | task will stay in uninterruptible state. If lockdep is | 213 | task will stay in uninterruptible state. If lockdep is |
214 | enabled then all held locks will also be reported. This | 214 | enabled then all held locks will also be reported. This |
215 | feature has negligible overhead. | 215 | feature has negligible overhead. |
216 | 216 | ||
217 | config BOOTPARAM_HUNG_TASK_PANIC | 217 | config BOOTPARAM_HUNG_TASK_PANIC |
218 | bool "Panic (Reboot) On Hung Tasks" | 218 | bool "Panic (Reboot) On Hung Tasks" |
219 | depends on DETECT_HUNG_TASK | 219 | depends on DETECT_HUNG_TASK |
220 | help | 220 | help |
221 | Say Y here to enable the kernel to panic on "hung tasks", | 221 | Say Y here to enable the kernel to panic on "hung tasks", |
222 | which are bugs that cause the kernel to leave a task stuck | 222 | which are bugs that cause the kernel to leave a task stuck |
223 | in uninterruptible "D" state. | 223 | in uninterruptible "D" state. |
224 | 224 | ||
225 | The panic can be used in combination with panic_timeout, | 225 | The panic can be used in combination with panic_timeout, |
226 | to cause the system to reboot automatically after a | 226 | to cause the system to reboot automatically after a |
227 | hung task has been detected. This feature is useful for | 227 | hung task has been detected. This feature is useful for |
228 | high-availability systems that have uptime guarantees and | 228 | high-availability systems that have uptime guarantees and |
229 | where a hung tasks must be resolved ASAP. | 229 | where a hung tasks must be resolved ASAP. |
230 | 230 | ||
231 | Say N if unsure. | 231 | Say N if unsure. |
232 | 232 | ||
233 | config BOOTPARAM_HUNG_TASK_PANIC_VALUE | 233 | config BOOTPARAM_HUNG_TASK_PANIC_VALUE |
234 | int | 234 | int |
235 | depends on DETECT_HUNG_TASK | 235 | depends on DETECT_HUNG_TASK |
236 | range 0 1 | 236 | range 0 1 |
237 | default 0 if !BOOTPARAM_HUNG_TASK_PANIC | 237 | default 0 if !BOOTPARAM_HUNG_TASK_PANIC |
238 | default 1 if BOOTPARAM_HUNG_TASK_PANIC | 238 | default 1 if BOOTPARAM_HUNG_TASK_PANIC |
239 | 239 | ||
240 | config SCHED_DEBUG | 240 | config SCHED_DEBUG |
241 | bool "Collect scheduler debugging info" | 241 | bool "Collect scheduler debugging info" |
242 | depends on DEBUG_KERNEL && PROC_FS | 242 | depends on DEBUG_KERNEL && PROC_FS |
243 | default y | 243 | default y |
244 | help | 244 | help |
245 | If you say Y here, the /proc/sched_debug file will be provided | 245 | If you say Y here, the /proc/sched_debug file will be provided |
246 | that can help debug the scheduler. The runtime overhead of this | 246 | that can help debug the scheduler. The runtime overhead of this |
247 | option is minimal. | 247 | option is minimal. |
248 | 248 | ||
249 | config SCHEDSTATS | 249 | config SCHEDSTATS |
250 | bool "Collect scheduler statistics" | 250 | bool "Collect scheduler statistics" |
251 | depends on DEBUG_KERNEL && PROC_FS | 251 | depends on DEBUG_KERNEL && PROC_FS |
252 | help | 252 | help |
253 | If you say Y here, additional code will be inserted into the | 253 | If you say Y here, additional code will be inserted into the |
254 | scheduler and related routines to collect statistics about | 254 | scheduler and related routines to collect statistics about |
255 | scheduler behavior and provide them in /proc/schedstat. These | 255 | scheduler behavior and provide them in /proc/schedstat. These |
256 | stats may be useful for both tuning and debugging the scheduler | 256 | stats may be useful for both tuning and debugging the scheduler |
257 | If you aren't debugging the scheduler or trying to tune a specific | 257 | If you aren't debugging the scheduler or trying to tune a specific |
258 | application, you can say N to avoid the very slight overhead | 258 | application, you can say N to avoid the very slight overhead |
259 | this adds. | 259 | this adds. |
260 | 260 | ||
261 | config TIMER_STATS | 261 | config TIMER_STATS |
262 | bool "Collect kernel timers statistics" | 262 | bool "Collect kernel timers statistics" |
263 | depends on DEBUG_KERNEL && PROC_FS | 263 | depends on DEBUG_KERNEL && PROC_FS |
264 | help | 264 | help |
265 | If you say Y here, additional code will be inserted into the | 265 | If you say Y here, additional code will be inserted into the |
266 | timer routines to collect statistics about kernel timers being | 266 | timer routines to collect statistics about kernel timers being |
267 | reprogrammed. The statistics can be read from /proc/timer_stats. | 267 | reprogrammed. The statistics can be read from /proc/timer_stats. |
268 | The statistics collection is started by writing 1 to /proc/timer_stats, | 268 | The statistics collection is started by writing 1 to /proc/timer_stats, |
269 | writing 0 stops it. This feature is useful to collect information | 269 | writing 0 stops it. This feature is useful to collect information |
270 | about timer usage patterns in kernel and userspace. This feature | 270 | about timer usage patterns in kernel and userspace. This feature |
271 | is lightweight if enabled in the kernel config but not activated | 271 | is lightweight if enabled in the kernel config but not activated |
272 | (it defaults to deactivated on bootup and will only be activated | 272 | (it defaults to deactivated on bootup and will only be activated |
273 | if some application like powertop activates it explicitly). | 273 | if some application like powertop activates it explicitly). |
274 | 274 | ||
275 | config DEBUG_OBJECTS | 275 | config DEBUG_OBJECTS |
276 | bool "Debug object operations" | 276 | bool "Debug object operations" |
277 | depends on DEBUG_KERNEL | 277 | depends on DEBUG_KERNEL |
278 | help | 278 | help |
279 | If you say Y here, additional code will be inserted into the | 279 | If you say Y here, additional code will be inserted into the |
280 | kernel to track the life time of various objects and validate | 280 | kernel to track the life time of various objects and validate |
281 | the operations on those objects. | 281 | the operations on those objects. |
282 | 282 | ||
283 | config DEBUG_OBJECTS_SELFTEST | 283 | config DEBUG_OBJECTS_SELFTEST |
284 | bool "Debug objects selftest" | 284 | bool "Debug objects selftest" |
285 | depends on DEBUG_OBJECTS | 285 | depends on DEBUG_OBJECTS |
286 | help | 286 | help |
287 | This enables the selftest of the object debug code. | 287 | This enables the selftest of the object debug code. |
288 | 288 | ||
289 | config DEBUG_OBJECTS_FREE | 289 | config DEBUG_OBJECTS_FREE |
290 | bool "Debug objects in freed memory" | 290 | bool "Debug objects in freed memory" |
291 | depends on DEBUG_OBJECTS | 291 | depends on DEBUG_OBJECTS |
292 | help | 292 | help |
293 | This enables checks whether a k/v free operation frees an area | 293 | This enables checks whether a k/v free operation frees an area |
294 | which contains an object which has not been deactivated | 294 | which contains an object which has not been deactivated |
295 | properly. This can make kmalloc/kfree-intensive workloads | 295 | properly. This can make kmalloc/kfree-intensive workloads |
296 | much slower. | 296 | much slower. |
297 | 297 | ||
298 | config DEBUG_OBJECTS_TIMERS | 298 | config DEBUG_OBJECTS_TIMERS |
299 | bool "Debug timer objects" | 299 | bool "Debug timer objects" |
300 | depends on DEBUG_OBJECTS | 300 | depends on DEBUG_OBJECTS |
301 | help | 301 | help |
302 | If you say Y here, additional code will be inserted into the | 302 | If you say Y here, additional code will be inserted into the |
303 | timer routines to track the life time of timer objects and | 303 | timer routines to track the life time of timer objects and |
304 | validate the timer operations. | 304 | validate the timer operations. |
305 | 305 | ||
306 | config DEBUG_OBJECTS_WORK | 306 | config DEBUG_OBJECTS_WORK |
307 | bool "Debug work objects" | 307 | bool "Debug work objects" |
308 | depends on DEBUG_OBJECTS | 308 | depends on DEBUG_OBJECTS |
309 | help | 309 | help |
310 | If you say Y here, additional code will be inserted into the | 310 | If you say Y here, additional code will be inserted into the |
311 | work queue routines to track the life time of work objects and | 311 | work queue routines to track the life time of work objects and |
312 | validate the work operations. | 312 | validate the work operations. |
313 | 313 | ||
314 | config DEBUG_OBJECTS_RCU_HEAD | 314 | config DEBUG_OBJECTS_RCU_HEAD |
315 | bool "Debug RCU callbacks objects" | 315 | bool "Debug RCU callbacks objects" |
316 | depends on DEBUG_OBJECTS && PREEMPT | 316 | depends on DEBUG_OBJECTS && PREEMPT |
317 | help | 317 | help |
318 | Enable this to turn on debugging of RCU list heads (call_rcu() usage). | 318 | Enable this to turn on debugging of RCU list heads (call_rcu() usage). |
319 | 319 | ||
320 | config DEBUG_OBJECTS_ENABLE_DEFAULT | 320 | config DEBUG_OBJECTS_ENABLE_DEFAULT |
321 | int "debug_objects bootup default value (0-1)" | 321 | int "debug_objects bootup default value (0-1)" |
322 | range 0 1 | 322 | range 0 1 |
323 | default "1" | 323 | default "1" |
324 | depends on DEBUG_OBJECTS | 324 | depends on DEBUG_OBJECTS |
325 | help | 325 | help |
326 | Debug objects boot parameter default value | 326 | Debug objects boot parameter default value |
327 | 327 | ||
328 | config DEBUG_SLAB | 328 | config DEBUG_SLAB |
329 | bool "Debug slab memory allocations" | 329 | bool "Debug slab memory allocations" |
330 | depends on DEBUG_KERNEL && SLAB && !KMEMCHECK | 330 | depends on DEBUG_KERNEL && SLAB && !KMEMCHECK |
331 | help | 331 | help |
332 | Say Y here to have the kernel do limited verification on memory | 332 | Say Y here to have the kernel do limited verification on memory |
333 | allocation as well as poisoning memory on free to catch use of freed | 333 | allocation as well as poisoning memory on free to catch use of freed |
334 | memory. This can make kmalloc/kfree-intensive workloads much slower. | 334 | memory. This can make kmalloc/kfree-intensive workloads much slower. |
335 | 335 | ||
336 | config DEBUG_SLAB_LEAK | 336 | config DEBUG_SLAB_LEAK |
337 | bool "Memory leak debugging" | 337 | bool "Memory leak debugging" |
338 | depends on DEBUG_SLAB | 338 | depends on DEBUG_SLAB |
339 | 339 | ||
340 | config SLUB_DEBUG_ON | 340 | config SLUB_DEBUG_ON |
341 | bool "SLUB debugging on by default" | 341 | bool "SLUB debugging on by default" |
342 | depends on SLUB && SLUB_DEBUG && !KMEMCHECK | 342 | depends on SLUB && SLUB_DEBUG && !KMEMCHECK |
343 | default n | 343 | default n |
344 | help | 344 | help |
345 | Boot with debugging on by default. SLUB boots by default with | 345 | Boot with debugging on by default. SLUB boots by default with |
346 | the runtime debug capabilities switched off. Enabling this is | 346 | the runtime debug capabilities switched off. Enabling this is |
347 | equivalent to specifying the "slub_debug" parameter on boot. | 347 | equivalent to specifying the "slub_debug" parameter on boot. |
348 | There is no support for more fine grained debug control like | 348 | There is no support for more fine grained debug control like |
349 | possible with slub_debug=xxx. SLUB debugging may be switched | 349 | possible with slub_debug=xxx. SLUB debugging may be switched |
350 | off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying | 350 | off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying |
351 | "slub_debug=-". | 351 | "slub_debug=-". |
352 | 352 | ||
353 | config SLUB_STATS | 353 | config SLUB_STATS |
354 | default n | 354 | default n |
355 | bool "Enable SLUB performance statistics" | 355 | bool "Enable SLUB performance statistics" |
356 | depends on SLUB && SLUB_DEBUG && SYSFS | 356 | depends on SLUB && SLUB_DEBUG && SYSFS |
357 | help | 357 | help |
358 | SLUB statistics are useful to debug SLUBs allocation behavior in | 358 | SLUB statistics are useful to debug SLUBs allocation behavior in |
359 | order find ways to optimize the allocator. This should never be | 359 | order find ways to optimize the allocator. This should never be |
360 | enabled for production use since keeping statistics slows down | 360 | enabled for production use since keeping statistics slows down |
361 | the allocator by a few percentage points. The slabinfo command | 361 | the allocator by a few percentage points. The slabinfo command |
362 | supports the determination of the most active slabs to figure | 362 | supports the determination of the most active slabs to figure |
363 | out which slabs are relevant to a particular load. | 363 | out which slabs are relevant to a particular load. |
364 | Try running: slabinfo -DA | 364 | Try running: slabinfo -DA |
365 | 365 | ||
366 | config DEBUG_KMEMLEAK | 366 | config DEBUG_KMEMLEAK |
367 | bool "Kernel memory leak detector" | 367 | bool "Kernel memory leak detector" |
368 | depends on DEBUG_KERNEL && EXPERIMENTAL && !MEMORY_HOTPLUG && \ | 368 | depends on DEBUG_KERNEL && EXPERIMENTAL && !MEMORY_HOTPLUG && \ |
369 | (X86 || ARM || PPC || S390 || SPARC64 || SUPERH || MICROBLAZE) | 369 | (X86 || ARM || PPC || S390 || SPARC64 || SUPERH || MICROBLAZE) |
370 | 370 | ||
371 | select DEBUG_FS if SYSFS | 371 | select DEBUG_FS if SYSFS |
372 | select STACKTRACE if STACKTRACE_SUPPORT | 372 | select STACKTRACE if STACKTRACE_SUPPORT |
373 | select KALLSYMS | 373 | select KALLSYMS |
374 | select CRC32 | 374 | select CRC32 |
375 | help | 375 | help |
376 | Say Y here if you want to enable the memory leak | 376 | Say Y here if you want to enable the memory leak |
377 | detector. The memory allocation/freeing is traced in a way | 377 | detector. The memory allocation/freeing is traced in a way |
378 | similar to the Boehm's conservative garbage collector, the | 378 | similar to the Boehm's conservative garbage collector, the |
379 | difference being that the orphan objects are not freed but | 379 | difference being that the orphan objects are not freed but |
380 | only shown in /sys/kernel/debug/kmemleak. Enabling this | 380 | only shown in /sys/kernel/debug/kmemleak. Enabling this |
381 | feature will introduce an overhead to memory | 381 | feature will introduce an overhead to memory |
382 | allocations. See Documentation/kmemleak.txt for more | 382 | allocations. See Documentation/kmemleak.txt for more |
383 | details. | 383 | details. |
384 | 384 | ||
385 | Enabling DEBUG_SLAB or SLUB_DEBUG may increase the chances | 385 | Enabling DEBUG_SLAB or SLUB_DEBUG may increase the chances |
386 | of finding leaks due to the slab objects poisoning. | 386 | of finding leaks due to the slab objects poisoning. |
387 | 387 | ||
388 | In order to access the kmemleak file, debugfs needs to be | 388 | In order to access the kmemleak file, debugfs needs to be |
389 | mounted (usually at /sys/kernel/debug). | 389 | mounted (usually at /sys/kernel/debug). |
390 | 390 | ||
391 | config DEBUG_KMEMLEAK_EARLY_LOG_SIZE | 391 | config DEBUG_KMEMLEAK_EARLY_LOG_SIZE |
392 | int "Maximum kmemleak early log entries" | 392 | int "Maximum kmemleak early log entries" |
393 | depends on DEBUG_KMEMLEAK | 393 | depends on DEBUG_KMEMLEAK |
394 | range 200 40000 | 394 | range 200 40000 |
395 | default 400 | 395 | default 400 |
396 | help | 396 | help |
397 | Kmemleak must track all the memory allocations to avoid | 397 | Kmemleak must track all the memory allocations to avoid |
398 | reporting false positives. Since memory may be allocated or | 398 | reporting false positives. Since memory may be allocated or |
399 | freed before kmemleak is initialised, an early log buffer is | 399 | freed before kmemleak is initialised, an early log buffer is |
400 | used to store these actions. If kmemleak reports "early log | 400 | used to store these actions. If kmemleak reports "early log |
401 | buffer exceeded", please increase this value. | 401 | buffer exceeded", please increase this value. |
402 | 402 | ||
403 | config DEBUG_KMEMLEAK_TEST | 403 | config DEBUG_KMEMLEAK_TEST |
404 | tristate "Simple test for the kernel memory leak detector" | 404 | tristate "Simple test for the kernel memory leak detector" |
405 | depends on DEBUG_KMEMLEAK | 405 | depends on DEBUG_KMEMLEAK |
406 | help | 406 | help |
407 | Say Y or M here to build a test for the kernel memory leak | 407 | Say Y or M here to build a test for the kernel memory leak |
408 | detector. This option enables a module that explicitly leaks | 408 | detector. This option enables a module that explicitly leaks |
409 | memory. | 409 | memory. |
410 | 410 | ||
411 | If unsure, say N. | 411 | If unsure, say N. |
412 | 412 | ||
413 | config DEBUG_KMEMLEAK_DEFAULT_OFF | 413 | config DEBUG_KMEMLEAK_DEFAULT_OFF |
414 | bool "Default kmemleak to off" | 414 | bool "Default kmemleak to off" |
415 | depends on DEBUG_KMEMLEAK | 415 | depends on DEBUG_KMEMLEAK |
416 | help | 416 | help |
417 | Say Y here to disable kmemleak by default. It can then be enabled | 417 | Say Y here to disable kmemleak by default. It can then be enabled |
418 | on the command line via kmemleak=on. | 418 | on the command line via kmemleak=on. |
419 | 419 | ||
420 | config DEBUG_PREEMPT | 420 | config DEBUG_PREEMPT |
421 | bool "Debug preemptible kernel" | 421 | bool "Debug preemptible kernel" |
422 | depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT | 422 | depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT |
423 | default y | 423 | default y |
424 | help | 424 | help |
425 | If you say Y here then the kernel will use a debug variant of the | 425 | If you say Y here then the kernel will use a debug variant of the |
426 | commonly used smp_processor_id() function and will print warnings | 426 | commonly used smp_processor_id() function and will print warnings |
427 | if kernel code uses it in a preemption-unsafe way. Also, the kernel | 427 | if kernel code uses it in a preemption-unsafe way. Also, the kernel |
428 | will detect preemption count underflows. | 428 | will detect preemption count underflows. |
429 | 429 | ||
430 | config DEBUG_RT_MUTEXES | 430 | config DEBUG_RT_MUTEXES |
431 | bool "RT Mutex debugging, deadlock detection" | 431 | bool "RT Mutex debugging, deadlock detection" |
432 | depends on DEBUG_KERNEL && RT_MUTEXES | 432 | depends on DEBUG_KERNEL && RT_MUTEXES |
433 | help | 433 | help |
434 | This allows rt mutex semantics violations and rt mutex related | 434 | This allows rt mutex semantics violations and rt mutex related |
435 | deadlocks (lockups) to be detected and reported automatically. | 435 | deadlocks (lockups) to be detected and reported automatically. |
436 | 436 | ||
437 | config DEBUG_PI_LIST | 437 | config DEBUG_PI_LIST |
438 | bool | 438 | bool |
439 | default y | 439 | default y |
440 | depends on DEBUG_RT_MUTEXES | 440 | depends on DEBUG_RT_MUTEXES |
441 | 441 | ||
442 | config RT_MUTEX_TESTER | 442 | config RT_MUTEX_TESTER |
443 | bool "Built-in scriptable tester for rt-mutexes" | 443 | bool "Built-in scriptable tester for rt-mutexes" |
444 | depends on DEBUG_KERNEL && RT_MUTEXES | 444 | depends on DEBUG_KERNEL && RT_MUTEXES |
445 | help | 445 | help |
446 | This option enables a rt-mutex tester. | 446 | This option enables a rt-mutex tester. |
447 | 447 | ||
448 | config DEBUG_SPINLOCK | 448 | config DEBUG_SPINLOCK |
449 | bool "Spinlock and rw-lock debugging: basic checks" | 449 | bool "Spinlock and rw-lock debugging: basic checks" |
450 | depends on DEBUG_KERNEL | 450 | depends on DEBUG_KERNEL |
451 | help | 451 | help |
452 | Say Y here and build SMP to catch missing spinlock initialization | 452 | Say Y here and build SMP to catch missing spinlock initialization |
453 | and certain other kinds of spinlock errors commonly made. This is | 453 | and certain other kinds of spinlock errors commonly made. This is |
454 | best used in conjunction with the NMI watchdog so that spinlock | 454 | best used in conjunction with the NMI watchdog so that spinlock |
455 | deadlocks are also debuggable. | 455 | deadlocks are also debuggable. |
456 | 456 | ||
457 | config DEBUG_MUTEXES | 457 | config DEBUG_MUTEXES |
458 | bool "Mutex debugging: basic checks" | 458 | bool "Mutex debugging: basic checks" |
459 | depends on DEBUG_KERNEL | 459 | depends on DEBUG_KERNEL |
460 | help | 460 | help |
461 | This feature allows mutex semantics violations to be detected and | 461 | This feature allows mutex semantics violations to be detected and |
462 | reported. | 462 | reported. |
463 | 463 | ||
464 | config DEBUG_LOCK_ALLOC | 464 | config DEBUG_LOCK_ALLOC |
465 | bool "Lock debugging: detect incorrect freeing of live locks" | 465 | bool "Lock debugging: detect incorrect freeing of live locks" |
466 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT | 466 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
467 | select DEBUG_SPINLOCK | 467 | select DEBUG_SPINLOCK |
468 | select DEBUG_MUTEXES | 468 | select DEBUG_MUTEXES |
469 | select LOCKDEP | 469 | select LOCKDEP |
470 | help | 470 | help |
471 | This feature will check whether any held lock (spinlock, rwlock, | 471 | This feature will check whether any held lock (spinlock, rwlock, |
472 | mutex or rwsem) is incorrectly freed by the kernel, via any of the | 472 | mutex or rwsem) is incorrectly freed by the kernel, via any of the |
473 | memory-freeing routines (kfree(), kmem_cache_free(), free_pages(), | 473 | memory-freeing routines (kfree(), kmem_cache_free(), free_pages(), |
474 | vfree(), etc.), whether a live lock is incorrectly reinitialized via | 474 | vfree(), etc.), whether a live lock is incorrectly reinitialized via |
475 | spin_lock_init()/mutex_init()/etc., or whether there is any lock | 475 | spin_lock_init()/mutex_init()/etc., or whether there is any lock |
476 | held during task exit. | 476 | held during task exit. |
477 | 477 | ||
478 | config PROVE_LOCKING | 478 | config PROVE_LOCKING |
479 | bool "Lock debugging: prove locking correctness" | 479 | bool "Lock debugging: prove locking correctness" |
480 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT | 480 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
481 | select LOCKDEP | 481 | select LOCKDEP |
482 | select DEBUG_SPINLOCK | 482 | select DEBUG_SPINLOCK |
483 | select DEBUG_MUTEXES | 483 | select DEBUG_MUTEXES |
484 | select DEBUG_LOCK_ALLOC | 484 | select DEBUG_LOCK_ALLOC |
485 | default n | 485 | default n |
486 | help | 486 | help |
487 | This feature enables the kernel to prove that all locking | 487 | This feature enables the kernel to prove that all locking |
488 | that occurs in the kernel runtime is mathematically | 488 | that occurs in the kernel runtime is mathematically |
489 | correct: that under no circumstance could an arbitrary (and | 489 | correct: that under no circumstance could an arbitrary (and |
490 | not yet triggered) combination of observed locking | 490 | not yet triggered) combination of observed locking |
491 | sequences (on an arbitrary number of CPUs, running an | 491 | sequences (on an arbitrary number of CPUs, running an |
492 | arbitrary number of tasks and interrupt contexts) cause a | 492 | arbitrary number of tasks and interrupt contexts) cause a |
493 | deadlock. | 493 | deadlock. |
494 | 494 | ||
495 | In short, this feature enables the kernel to report locking | 495 | In short, this feature enables the kernel to report locking |
496 | related deadlocks before they actually occur. | 496 | related deadlocks before they actually occur. |
497 | 497 | ||
498 | The proof does not depend on how hard and complex a | 498 | The proof does not depend on how hard and complex a |
499 | deadlock scenario would be to trigger: how many | 499 | deadlock scenario would be to trigger: how many |
500 | participant CPUs, tasks and irq-contexts would be needed | 500 | participant CPUs, tasks and irq-contexts would be needed |
501 | for it to trigger. The proof also does not depend on | 501 | for it to trigger. The proof also does not depend on |
502 | timing: if a race and a resulting deadlock is possible | 502 | timing: if a race and a resulting deadlock is possible |
503 | theoretically (no matter how unlikely the race scenario | 503 | theoretically (no matter how unlikely the race scenario |
504 | is), it will be proven so and will immediately be | 504 | is), it will be proven so and will immediately be |
505 | reported by the kernel (once the event is observed that | 505 | reported by the kernel (once the event is observed that |
506 | makes the deadlock theoretically possible). | 506 | makes the deadlock theoretically possible). |
507 | 507 | ||
508 | If a deadlock is impossible (i.e. the locking rules, as | 508 | If a deadlock is impossible (i.e. the locking rules, as |
509 | observed by the kernel, are mathematically correct), the | 509 | observed by the kernel, are mathematically correct), the |
510 | kernel reports nothing. | 510 | kernel reports nothing. |
511 | 511 | ||
512 | NOTE: this feature can also be enabled for rwlocks, mutexes | 512 | NOTE: this feature can also be enabled for rwlocks, mutexes |
513 | and rwsems - in which case all dependencies between these | 513 | and rwsems - in which case all dependencies between these |
514 | different locking variants are observed and mapped too, and | 514 | different locking variants are observed and mapped too, and |
515 | the proof of observed correctness is also maintained for an | 515 | the proof of observed correctness is also maintained for an |
516 | arbitrary combination of these separate locking variants. | 516 | arbitrary combination of these separate locking variants. |
517 | 517 | ||
518 | For more details, see Documentation/lockdep-design.txt. | 518 | For more details, see Documentation/lockdep-design.txt. |
519 | 519 | ||
520 | config PROVE_RCU | 520 | config PROVE_RCU |
521 | bool "RCU debugging: prove RCU correctness" | 521 | bool "RCU debugging: prove RCU correctness" |
522 | depends on PROVE_LOCKING | 522 | depends on PROVE_LOCKING |
523 | default n | 523 | default n |
524 | help | 524 | help |
525 | This feature enables lockdep extensions that check for correct | 525 | This feature enables lockdep extensions that check for correct |
526 | use of RCU APIs. This is currently under development. Say Y | 526 | use of RCU APIs. This is currently under development. Say Y |
527 | if you want to debug RCU usage or help work on the PROVE_RCU | 527 | if you want to debug RCU usage or help work on the PROVE_RCU |
528 | feature. | 528 | feature. |
529 | 529 | ||
530 | Say N if you are unsure. | 530 | Say N if you are unsure. |
531 | 531 | ||
532 | config PROVE_RCU_REPEATEDLY | 532 | config PROVE_RCU_REPEATEDLY |
533 | bool "RCU debugging: don't disable PROVE_RCU on first splat" | 533 | bool "RCU debugging: don't disable PROVE_RCU on first splat" |
534 | depends on PROVE_RCU | 534 | depends on PROVE_RCU |
535 | default n | 535 | default n |
536 | help | 536 | help |
537 | By itself, PROVE_RCU will disable checking upon issuing the | 537 | By itself, PROVE_RCU will disable checking upon issuing the |
538 | first warning (or "splat"). This feature prevents such | 538 | first warning (or "splat"). This feature prevents such |
539 | disabling, allowing multiple RCU-lockdep warnings to be printed | 539 | disabling, allowing multiple RCU-lockdep warnings to be printed |
540 | on a single reboot. | 540 | on a single reboot. |
541 | 541 | ||
542 | Say N if you are unsure. | 542 | Say N if you are unsure. |
543 | 543 | ||
544 | config LOCKDEP | 544 | config LOCKDEP |
545 | bool | 545 | bool |
546 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT | 546 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
547 | select STACKTRACE | 547 | select STACKTRACE |
548 | select FRAME_POINTER if !MIPS && !PPC && !ARM_UNWIND && !S390 && !MICROBLAZE | 548 | select FRAME_POINTER if !MIPS && !PPC && !ARM_UNWIND && !S390 && !MICROBLAZE |
549 | select KALLSYMS | 549 | select KALLSYMS |
550 | select KALLSYMS_ALL | 550 | select KALLSYMS_ALL |
551 | 551 | ||
552 | config LOCK_STAT | 552 | config LOCK_STAT |
553 | bool "Lock usage statistics" | 553 | bool "Lock usage statistics" |
554 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT | 554 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
555 | select LOCKDEP | 555 | select LOCKDEP |
556 | select DEBUG_SPINLOCK | 556 | select DEBUG_SPINLOCK |
557 | select DEBUG_MUTEXES | 557 | select DEBUG_MUTEXES |
558 | select DEBUG_LOCK_ALLOC | 558 | select DEBUG_LOCK_ALLOC |
559 | default n | 559 | default n |
560 | help | 560 | help |
561 | This feature enables tracking lock contention points | 561 | This feature enables tracking lock contention points |
562 | 562 | ||
563 | For more details, see Documentation/lockstat.txt | 563 | For more details, see Documentation/lockstat.txt |
564 | 564 | ||
565 | This also enables lock events required by "perf lock", | 565 | This also enables lock events required by "perf lock", |
566 | subcommand of perf. | 566 | subcommand of perf. |
567 | If you want to use "perf lock", you also need to turn on | 567 | If you want to use "perf lock", you also need to turn on |
568 | CONFIG_EVENT_TRACING. | 568 | CONFIG_EVENT_TRACING. |
569 | 569 | ||
570 | CONFIG_LOCK_STAT defines "contended" and "acquired" lock events. | 570 | CONFIG_LOCK_STAT defines "contended" and "acquired" lock events. |
571 | (CONFIG_LOCKDEP defines "acquire" and "release" events.) | 571 | (CONFIG_LOCKDEP defines "acquire" and "release" events.) |
572 | 572 | ||
573 | config DEBUG_LOCKDEP | 573 | config DEBUG_LOCKDEP |
574 | bool "Lock dependency engine debugging" | 574 | bool "Lock dependency engine debugging" |
575 | depends on DEBUG_KERNEL && LOCKDEP | 575 | depends on DEBUG_KERNEL && LOCKDEP |
576 | help | 576 | help |
577 | If you say Y here, the lock dependency engine will do | 577 | If you say Y here, the lock dependency engine will do |
578 | additional runtime checks to debug itself, at the price | 578 | additional runtime checks to debug itself, at the price |
579 | of more runtime overhead. | 579 | of more runtime overhead. |
580 | 580 | ||
581 | config TRACE_IRQFLAGS | 581 | config TRACE_IRQFLAGS |
582 | depends on DEBUG_KERNEL | 582 | depends on DEBUG_KERNEL |
583 | bool | 583 | bool |
584 | default y | 584 | default y |
585 | depends on TRACE_IRQFLAGS_SUPPORT | 585 | depends on TRACE_IRQFLAGS_SUPPORT |
586 | depends on PROVE_LOCKING | 586 | depends on PROVE_LOCKING |
587 | 587 | ||
588 | config DEBUG_SPINLOCK_SLEEP | 588 | config DEBUG_SPINLOCK_SLEEP |
589 | bool "Spinlock debugging: sleep-inside-spinlock checking" | 589 | bool "Spinlock debugging: sleep-inside-spinlock checking" |
590 | depends on DEBUG_KERNEL | 590 | depends on DEBUG_KERNEL |
591 | help | 591 | help |
592 | If you say Y here, various routines which may sleep will become very | 592 | If you say Y here, various routines which may sleep will become very |
593 | noisy if they are called with a spinlock held. | 593 | noisy if they are called with a spinlock held. |
594 | 594 | ||
595 | config DEBUG_LOCKING_API_SELFTESTS | 595 | config DEBUG_LOCKING_API_SELFTESTS |
596 | bool "Locking API boot-time self-tests" | 596 | bool "Locking API boot-time self-tests" |
597 | depends on DEBUG_KERNEL | 597 | depends on DEBUG_KERNEL |
598 | help | 598 | help |
599 | Say Y here if you want the kernel to run a short self-test during | 599 | Say Y here if you want the kernel to run a short self-test during |
600 | bootup. The self-test checks whether common types of locking bugs | 600 | bootup. The self-test checks whether common types of locking bugs |
601 | are detected by debugging mechanisms or not. (if you disable | 601 | are detected by debugging mechanisms or not. (if you disable |
602 | lock debugging then those bugs wont be detected of course.) | 602 | lock debugging then those bugs wont be detected of course.) |
603 | The following locking APIs are covered: spinlocks, rwlocks, | 603 | The following locking APIs are covered: spinlocks, rwlocks, |
604 | mutexes and rwsems. | 604 | mutexes and rwsems. |
605 | 605 | ||
606 | config STACKTRACE | 606 | config STACKTRACE |
607 | bool | 607 | bool |
608 | depends on STACKTRACE_SUPPORT | 608 | depends on STACKTRACE_SUPPORT |
609 | 609 | ||
610 | config DEBUG_KOBJECT | 610 | config DEBUG_KOBJECT |
611 | bool "kobject debugging" | 611 | bool "kobject debugging" |
612 | depends on DEBUG_KERNEL | 612 | depends on DEBUG_KERNEL |
613 | help | 613 | help |
614 | If you say Y here, some extra kobject debugging messages will be sent | 614 | If you say Y here, some extra kobject debugging messages will be sent |
615 | to the syslog. | 615 | to the syslog. |
616 | 616 | ||
617 | config DEBUG_HIGHMEM | 617 | config DEBUG_HIGHMEM |
618 | bool "Highmem debugging" | 618 | bool "Highmem debugging" |
619 | depends on DEBUG_KERNEL && HIGHMEM | 619 | depends on DEBUG_KERNEL && HIGHMEM |
620 | help | 620 | help |
621 | This options enables addition error checking for high memory systems. | 621 | This options enables addition error checking for high memory systems. |
622 | Disable for production systems. | 622 | Disable for production systems. |
623 | 623 | ||
624 | config DEBUG_BUGVERBOSE | 624 | config DEBUG_BUGVERBOSE |
625 | bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EMBEDDED | 625 | bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EMBEDDED |
626 | depends on BUG | 626 | depends on BUG |
627 | depends on ARM || AVR32 || M32R || M68K || SPARC32 || SPARC64 || \ | 627 | depends on ARM || AVR32 || M32R || M68K || SPARC32 || SPARC64 || \ |
628 | FRV || SUPERH || GENERIC_BUG || BLACKFIN || MN10300 | 628 | FRV || SUPERH || GENERIC_BUG || BLACKFIN || MN10300 |
629 | default y | 629 | default y |
630 | help | 630 | help |
631 | Say Y here to make BUG() panics output the file name and line number | 631 | Say Y here to make BUG() panics output the file name and line number |
632 | of the BUG call as well as the EIP and oops trace. This aids | 632 | of the BUG call as well as the EIP and oops trace. This aids |
633 | debugging but costs about 70-100K of memory. | 633 | debugging but costs about 70-100K of memory. |
634 | 634 | ||
635 | config DEBUG_INFO | 635 | config DEBUG_INFO |
636 | bool "Compile the kernel with debug info" | 636 | bool "Compile the kernel with debug info" |
637 | depends on DEBUG_KERNEL | 637 | depends on DEBUG_KERNEL |
638 | help | 638 | help |
639 | If you say Y here the resulting kernel image will include | 639 | If you say Y here the resulting kernel image will include |
640 | debugging info resulting in a larger kernel image. | 640 | debugging info resulting in a larger kernel image. |
641 | This adds debug symbols to the kernel and modules (gcc -g), and | 641 | This adds debug symbols to the kernel and modules (gcc -g), and |
642 | is needed if you intend to use kernel crashdump or binary object | 642 | is needed if you intend to use kernel crashdump or binary object |
643 | tools like crash, kgdb, LKCD, gdb, etc on the kernel. | 643 | tools like crash, kgdb, LKCD, gdb, etc on the kernel. |
644 | Say Y here only if you plan to debug the kernel. | 644 | Say Y here only if you plan to debug the kernel. |
645 | 645 | ||
646 | If unsure, say N. | 646 | If unsure, say N. |
647 | 647 | ||
648 | config DEBUG_INFO_REDUCED | 648 | config DEBUG_INFO_REDUCED |
649 | bool "Reduce debugging information" | 649 | bool "Reduce debugging information" |
650 | depends on DEBUG_INFO | 650 | depends on DEBUG_INFO |
651 | help | 651 | help |
652 | If you say Y here gcc is instructed to generate less debugging | 652 | If you say Y here gcc is instructed to generate less debugging |
653 | information for structure types. This means that tools that | 653 | information for structure types. This means that tools that |
654 | need full debugging information (like kgdb or systemtap) won't | 654 | need full debugging information (like kgdb or systemtap) won't |
655 | be happy. But if you merely need debugging information to | 655 | be happy. But if you merely need debugging information to |
656 | resolve line numbers there is no loss. Advantage is that | 656 | resolve line numbers there is no loss. Advantage is that |
657 | build directory object sizes shrink dramatically over a full | 657 | build directory object sizes shrink dramatically over a full |
658 | DEBUG_INFO build and compile times are reduced too. | 658 | DEBUG_INFO build and compile times are reduced too. |
659 | Only works with newer gcc versions. | 659 | Only works with newer gcc versions. |
660 | 660 | ||
661 | config DEBUG_VM | 661 | config DEBUG_VM |
662 | bool "Debug VM" | 662 | bool "Debug VM" |
663 | depends on DEBUG_KERNEL | 663 | depends on DEBUG_KERNEL |
664 | help | 664 | help |
665 | Enable this to turn on extended checks in the virtual-memory system | 665 | Enable this to turn on extended checks in the virtual-memory system |
666 | that may impact performance. | 666 | that may impact performance. |
667 | 667 | ||
668 | If unsure, say N. | 668 | If unsure, say N. |
669 | 669 | ||
670 | config DEBUG_VIRTUAL | 670 | config DEBUG_VIRTUAL |
671 | bool "Debug VM translations" | 671 | bool "Debug VM translations" |
672 | depends on DEBUG_KERNEL && X86 | 672 | depends on DEBUG_KERNEL && X86 |
673 | help | 673 | help |
674 | Enable some costly sanity checks in virtual to page code. This can | 674 | Enable some costly sanity checks in virtual to page code. This can |
675 | catch mistakes with virt_to_page() and friends. | 675 | catch mistakes with virt_to_page() and friends. |
676 | 676 | ||
677 | If unsure, say N. | 677 | If unsure, say N. |
678 | 678 | ||
679 | config DEBUG_NOMMU_REGIONS | 679 | config DEBUG_NOMMU_REGIONS |
680 | bool "Debug the global anon/private NOMMU mapping region tree" | 680 | bool "Debug the global anon/private NOMMU mapping region tree" |
681 | depends on DEBUG_KERNEL && !MMU | 681 | depends on DEBUG_KERNEL && !MMU |
682 | help | 682 | help |
683 | This option causes the global tree of anonymous and private mapping | 683 | This option causes the global tree of anonymous and private mapping |
684 | regions to be regularly checked for invalid topology. | 684 | regions to be regularly checked for invalid topology. |
685 | 685 | ||
686 | config DEBUG_WRITECOUNT | 686 | config DEBUG_WRITECOUNT |
687 | bool "Debug filesystem writers count" | 687 | bool "Debug filesystem writers count" |
688 | depends on DEBUG_KERNEL | 688 | depends on DEBUG_KERNEL |
689 | help | 689 | help |
690 | Enable this to catch wrong use of the writers count in struct | 690 | Enable this to catch wrong use of the writers count in struct |
691 | vfsmount. This will increase the size of each file struct by | 691 | vfsmount. This will increase the size of each file struct by |
692 | 32 bits. | 692 | 32 bits. |
693 | 693 | ||
694 | If unsure, say N. | 694 | If unsure, say N. |
695 | 695 | ||
696 | config DEBUG_MEMORY_INIT | 696 | config DEBUG_MEMORY_INIT |
697 | bool "Debug memory initialisation" if EMBEDDED | 697 | bool "Debug memory initialisation" if EMBEDDED |
698 | default !EMBEDDED | 698 | default !EMBEDDED |
699 | help | 699 | help |
700 | Enable this for additional checks during memory initialisation. | 700 | Enable this for additional checks during memory initialisation. |
701 | The sanity checks verify aspects of the VM such as the memory model | 701 | The sanity checks verify aspects of the VM such as the memory model |
702 | and other information provided by the architecture. Verbose | 702 | and other information provided by the architecture. Verbose |
703 | information will be printed at KERN_DEBUG loglevel depending | 703 | information will be printed at KERN_DEBUG loglevel depending |
704 | on the mminit_loglevel= command-line option. | 704 | on the mminit_loglevel= command-line option. |
705 | 705 | ||
706 | If unsure, say Y | 706 | If unsure, say Y |
707 | 707 | ||
708 | config DEBUG_LIST | 708 | config DEBUG_LIST |
709 | bool "Debug linked list manipulation" | 709 | bool "Debug linked list manipulation" |
710 | depends on DEBUG_KERNEL | 710 | depends on DEBUG_KERNEL |
711 | help | 711 | help |
712 | Enable this to turn on extended checks in the linked-list | 712 | Enable this to turn on extended checks in the linked-list |
713 | walking routines. | 713 | walking routines. |
714 | 714 | ||
715 | If unsure, say N. | 715 | If unsure, say N. |
716 | 716 | ||
717 | config DEBUG_SG | 717 | config DEBUG_SG |
718 | bool "Debug SG table operations" | 718 | bool "Debug SG table operations" |
719 | depends on DEBUG_KERNEL | 719 | depends on DEBUG_KERNEL |
720 | help | 720 | help |
721 | Enable this to turn on checks on scatter-gather tables. This can | 721 | Enable this to turn on checks on scatter-gather tables. This can |
722 | help find problems with drivers that do not properly initialize | 722 | help find problems with drivers that do not properly initialize |
723 | their sg tables. | 723 | their sg tables. |
724 | 724 | ||
725 | If unsure, say N. | 725 | If unsure, say N. |
726 | 726 | ||
727 | config DEBUG_NOTIFIERS | 727 | config DEBUG_NOTIFIERS |
728 | bool "Debug notifier call chains" | 728 | bool "Debug notifier call chains" |
729 | depends on DEBUG_KERNEL | 729 | depends on DEBUG_KERNEL |
730 | help | 730 | help |
731 | Enable this to turn on sanity checking for notifier call chains. | 731 | Enable this to turn on sanity checking for notifier call chains. |
732 | This is most useful for kernel developers to make sure that | 732 | This is most useful for kernel developers to make sure that |
733 | modules properly unregister themselves from notifier chains. | 733 | modules properly unregister themselves from notifier chains. |
734 | This is a relatively cheap check but if you care about maximum | 734 | This is a relatively cheap check but if you care about maximum |
735 | performance, say N. | 735 | performance, say N. |
736 | 736 | ||
737 | config DEBUG_CREDENTIALS | 737 | config DEBUG_CREDENTIALS |
738 | bool "Debug credential management" | 738 | bool "Debug credential management" |
739 | depends on DEBUG_KERNEL | 739 | depends on DEBUG_KERNEL |
740 | help | 740 | help |
741 | Enable this to turn on some debug checking for credential | 741 | Enable this to turn on some debug checking for credential |
742 | management. The additional code keeps track of the number of | 742 | management. The additional code keeps track of the number of |
743 | pointers from task_structs to any given cred struct, and checks to | 743 | pointers from task_structs to any given cred struct, and checks to |
744 | see that this number never exceeds the usage count of the cred | 744 | see that this number never exceeds the usage count of the cred |
745 | struct. | 745 | struct. |
746 | 746 | ||
747 | Furthermore, if SELinux is enabled, this also checks that the | 747 | Furthermore, if SELinux is enabled, this also checks that the |
748 | security pointer in the cred struct is never seen to be invalid. | 748 | security pointer in the cred struct is never seen to be invalid. |
749 | 749 | ||
750 | If unsure, say N. | 750 | If unsure, say N. |
751 | 751 | ||
752 | # | 752 | # |
753 | # Select this config option from the architecture Kconfig, if it | 753 | # Select this config option from the architecture Kconfig, if it |
754 | # it is preferred to always offer frame pointers as a config | 754 | # it is preferred to always offer frame pointers as a config |
755 | # option on the architecture (regardless of KERNEL_DEBUG): | 755 | # option on the architecture (regardless of KERNEL_DEBUG): |
756 | # | 756 | # |
757 | config ARCH_WANT_FRAME_POINTERS | 757 | config ARCH_WANT_FRAME_POINTERS |
758 | bool | 758 | bool |
759 | help | 759 | help |
760 | 760 | ||
761 | config FRAME_POINTER | 761 | config FRAME_POINTER |
762 | bool "Compile the kernel with frame pointers" | 762 | bool "Compile the kernel with frame pointers" |
763 | depends on DEBUG_KERNEL && \ | 763 | depends on DEBUG_KERNEL && \ |
764 | (CRIS || M68K || M68KNOMMU || FRV || UML || \ | 764 | (CRIS || M68K || M68KNOMMU || FRV || UML || \ |
765 | AVR32 || SUPERH || BLACKFIN || MN10300) || \ | 765 | AVR32 || SUPERH || BLACKFIN || MN10300) || \ |
766 | ARCH_WANT_FRAME_POINTERS | 766 | ARCH_WANT_FRAME_POINTERS |
767 | default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS | 767 | default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS |
768 | help | 768 | help |
769 | If you say Y here the resulting kernel image will be slightly | 769 | If you say Y here the resulting kernel image will be slightly |
770 | larger and slower, but it gives very useful debugging information | 770 | larger and slower, but it gives very useful debugging information |
771 | in case of kernel bugs. (precise oopses/stacktraces/warnings) | 771 | in case of kernel bugs. (precise oopses/stacktraces/warnings) |
772 | 772 | ||
773 | config BOOT_PRINTK_DELAY | 773 | config BOOT_PRINTK_DELAY |
774 | bool "Delay each boot printk message by N milliseconds" | 774 | bool "Delay each boot printk message by N milliseconds" |
775 | depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY | 775 | depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY |
776 | help | 776 | help |
777 | This build option allows you to read kernel boot messages | 777 | This build option allows you to read kernel boot messages |
778 | by inserting a short delay after each one. The delay is | 778 | by inserting a short delay after each one. The delay is |
779 | specified in milliseconds on the kernel command line, | 779 | specified in milliseconds on the kernel command line, |
780 | using "boot_delay=N". | 780 | using "boot_delay=N". |
781 | 781 | ||
782 | It is likely that you would also need to use "lpj=M" to preset | 782 | It is likely that you would also need to use "lpj=M" to preset |
783 | the "loops per jiffie" value. | 783 | the "loops per jiffie" value. |
784 | See a previous boot log for the "lpj" value to use for your | 784 | See a previous boot log for the "lpj" value to use for your |
785 | system, and then set "lpj=M" before setting "boot_delay=N". | 785 | system, and then set "lpj=M" before setting "boot_delay=N". |
786 | NOTE: Using this option may adversely affect SMP systems. | 786 | NOTE: Using this option may adversely affect SMP systems. |
787 | I.e., processors other than the first one may not boot up. | 787 | I.e., processors other than the first one may not boot up. |
788 | BOOT_PRINTK_DELAY also may cause DETECT_SOFTLOCKUP to detect | 788 | BOOT_PRINTK_DELAY also may cause DETECT_SOFTLOCKUP to detect |
789 | what it believes to be lockup conditions. | 789 | what it believes to be lockup conditions. |
790 | 790 | ||
791 | config RCU_TORTURE_TEST | 791 | config RCU_TORTURE_TEST |
792 | tristate "torture tests for RCU" | 792 | tristate "torture tests for RCU" |
793 | depends on DEBUG_KERNEL | 793 | depends on DEBUG_KERNEL |
794 | default n | 794 | default n |
795 | help | 795 | help |
796 | This option provides a kernel module that runs torture tests | 796 | This option provides a kernel module that runs torture tests |
797 | on the RCU infrastructure. The kernel module may be built | 797 | on the RCU infrastructure. The kernel module may be built |
798 | after the fact on the running kernel to be tested, if desired. | 798 | after the fact on the running kernel to be tested, if desired. |
799 | 799 | ||
800 | Say Y here if you want RCU torture tests to be built into | 800 | Say Y here if you want RCU torture tests to be built into |
801 | the kernel. | 801 | the kernel. |
802 | Say M if you want the RCU torture tests to build as a module. | 802 | Say M if you want the RCU torture tests to build as a module. |
803 | Say N if you are unsure. | 803 | Say N if you are unsure. |
804 | 804 | ||
805 | config RCU_TORTURE_TEST_RUNNABLE | 805 | config RCU_TORTURE_TEST_RUNNABLE |
806 | bool "torture tests for RCU runnable by default" | 806 | bool "torture tests for RCU runnable by default" |
807 | depends on RCU_TORTURE_TEST = y | 807 | depends on RCU_TORTURE_TEST = y |
808 | default n | 808 | default n |
809 | help | 809 | help |
810 | This option provides a way to build the RCU torture tests | 810 | This option provides a way to build the RCU torture tests |
811 | directly into the kernel without them starting up at boot | 811 | directly into the kernel without them starting up at boot |
812 | time. You can use /proc/sys/kernel/rcutorture_runnable | 812 | time. You can use /proc/sys/kernel/rcutorture_runnable |
813 | to manually override this setting. This /proc file is | 813 | to manually override this setting. This /proc file is |
814 | available only when the RCU torture tests have been built | 814 | available only when the RCU torture tests have been built |
815 | into the kernel. | 815 | into the kernel. |
816 | 816 | ||
817 | Say Y here if you want the RCU torture tests to start during | 817 | Say Y here if you want the RCU torture tests to start during |
818 | boot (you probably don't). | 818 | boot (you probably don't). |
819 | Say N here if you want the RCU torture tests to start only | 819 | Say N here if you want the RCU torture tests to start only |
820 | after being manually enabled via /proc. | 820 | after being manually enabled via /proc. |
821 | 821 | ||
822 | config RCU_CPU_STALL_DETECTOR | 822 | config RCU_CPU_STALL_DETECTOR |
823 | bool "Check for stalled CPUs delaying RCU grace periods" | 823 | bool "Check for stalled CPUs delaying RCU grace periods" |
824 | depends on TREE_RCU || TREE_PREEMPT_RCU | 824 | depends on TREE_RCU || TREE_PREEMPT_RCU |
825 | default y | 825 | default y |
826 | help | 826 | help |
827 | This option causes RCU to printk information on which | 827 | This option causes RCU to printk information on which |
828 | CPUs are delaying the current grace period, but only when | 828 | CPUs are delaying the current grace period, but only when |
829 | the grace period extends for excessive time periods. | 829 | the grace period extends for excessive time periods. |
830 | 830 | ||
831 | Say N if you want to disable such checks. | 831 | Say N if you want to disable such checks. |
832 | 832 | ||
833 | Say Y if you are unsure. | 833 | Say Y if you are unsure. |
834 | 834 | ||
835 | config RCU_CPU_STALL_VERBOSE | 835 | config RCU_CPU_STALL_VERBOSE |
836 | bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR" | 836 | bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR" |
837 | depends on RCU_CPU_STALL_DETECTOR && TREE_PREEMPT_RCU | 837 | depends on RCU_CPU_STALL_DETECTOR && TREE_PREEMPT_RCU |
838 | default y | 838 | default y |
839 | help | 839 | help |
840 | This option causes RCU to printk detailed per-task information | 840 | This option causes RCU to printk detailed per-task information |
841 | for any tasks that are stalling the current RCU grace period. | 841 | for any tasks that are stalling the current RCU grace period. |
842 | 842 | ||
843 | Say N if you are unsure. | 843 | Say N if you are unsure. |
844 | 844 | ||
845 | Say Y if you want to enable such checks. | 845 | Say Y if you want to enable such checks. |
846 | 846 | ||
847 | config KPROBES_SANITY_TEST | 847 | config KPROBES_SANITY_TEST |
848 | bool "Kprobes sanity tests" | 848 | bool "Kprobes sanity tests" |
849 | depends on DEBUG_KERNEL | 849 | depends on DEBUG_KERNEL |
850 | depends on KPROBES | 850 | depends on KPROBES |
851 | default n | 851 | default n |
852 | help | 852 | help |
853 | This option provides for testing basic kprobes functionality on | 853 | This option provides for testing basic kprobes functionality on |
854 | boot. A sample kprobe, jprobe and kretprobe are inserted and | 854 | boot. A sample kprobe, jprobe and kretprobe are inserted and |
855 | verified for functionality. | 855 | verified for functionality. |
856 | 856 | ||
857 | Say N if you are unsure. | 857 | Say N if you are unsure. |
858 | 858 | ||
859 | config BACKTRACE_SELF_TEST | 859 | config BACKTRACE_SELF_TEST |
860 | tristate "Self test for the backtrace code" | 860 | tristate "Self test for the backtrace code" |
861 | depends on DEBUG_KERNEL | 861 | depends on DEBUG_KERNEL |
862 | default n | 862 | default n |
863 | help | 863 | help |
864 | This option provides a kernel module that can be used to test | 864 | This option provides a kernel module that can be used to test |
865 | the kernel stack backtrace code. This option is not useful | 865 | the kernel stack backtrace code. This option is not useful |
866 | for distributions or general kernels, but only for kernel | 866 | for distributions or general kernels, but only for kernel |
867 | developers working on architecture code. | 867 | developers working on architecture code. |
868 | 868 | ||
869 | Note that if you want to also test saved backtraces, you will | 869 | Note that if you want to also test saved backtraces, you will |
870 | have to enable STACKTRACE as well. | 870 | have to enable STACKTRACE as well. |
871 | 871 | ||
872 | Say N if you are unsure. | 872 | Say N if you are unsure. |
873 | 873 | ||
874 | config DEBUG_BLOCK_EXT_DEVT | 874 | config DEBUG_BLOCK_EXT_DEVT |
875 | bool "Force extended block device numbers and spread them" | 875 | bool "Force extended block device numbers and spread them" |
876 | depends on DEBUG_KERNEL | 876 | depends on DEBUG_KERNEL |
877 | depends on BLOCK | 877 | depends on BLOCK |
878 | default n | 878 | default n |
879 | help | 879 | help |
880 | BIG FAT WARNING: ENABLING THIS OPTION MIGHT BREAK BOOTING ON | 880 | BIG FAT WARNING: ENABLING THIS OPTION MIGHT BREAK BOOTING ON |
881 | SOME DISTRIBUTIONS. DO NOT ENABLE THIS UNLESS YOU KNOW WHAT | 881 | SOME DISTRIBUTIONS. DO NOT ENABLE THIS UNLESS YOU KNOW WHAT |
882 | YOU ARE DOING. Distros, please enable this and fix whatever | 882 | YOU ARE DOING. Distros, please enable this and fix whatever |
883 | is broken. | 883 | is broken. |
884 | 884 | ||
885 | Conventionally, block device numbers are allocated from | 885 | Conventionally, block device numbers are allocated from |
886 | predetermined contiguous area. However, extended block area | 886 | predetermined contiguous area. However, extended block area |
887 | may introduce non-contiguous block device numbers. This | 887 | may introduce non-contiguous block device numbers. This |
888 | option forces most block device numbers to be allocated from | 888 | option forces most block device numbers to be allocated from |
889 | the extended space and spreads them to discover kernel or | 889 | the extended space and spreads them to discover kernel or |
890 | userland code paths which assume predetermined contiguous | 890 | userland code paths which assume predetermined contiguous |
891 | device number allocation. | 891 | device number allocation. |
892 | 892 | ||
893 | Note that turning on this debug option shuffles all the | 893 | Note that turning on this debug option shuffles all the |
894 | device numbers for all IDE and SCSI devices including libata | 894 | device numbers for all IDE and SCSI devices including libata |
895 | ones, so root partition specified using device number | 895 | ones, so root partition specified using device number |
896 | directly (via rdev or root=MAJ:MIN) won't work anymore. | 896 | directly (via rdev or root=MAJ:MIN) won't work anymore. |
897 | Textual device names (root=/dev/sdXn) will continue to work. | 897 | Textual device names (root=/dev/sdXn) will continue to work. |
898 | 898 | ||
899 | Say N if you are unsure. | 899 | Say N if you are unsure. |
900 | 900 | ||
901 | config DEBUG_FORCE_WEAK_PER_CPU | 901 | config DEBUG_FORCE_WEAK_PER_CPU |
902 | bool "Force weak per-cpu definitions" | 902 | bool "Force weak per-cpu definitions" |
903 | depends on DEBUG_KERNEL | 903 | depends on DEBUG_KERNEL |
904 | help | 904 | help |
905 | s390 and alpha require percpu variables in modules to be | 905 | s390 and alpha require percpu variables in modules to be |
906 | defined weak to work around addressing range issue which | 906 | defined weak to work around addressing range issue which |
907 | puts the following two restrictions on percpu variable | 907 | puts the following two restrictions on percpu variable |
908 | definitions. | 908 | definitions. |
909 | 909 | ||
910 | 1. percpu symbols must be unique whether static or not | 910 | 1. percpu symbols must be unique whether static or not |
911 | 2. percpu variables can't be defined inside a function | 911 | 2. percpu variables can't be defined inside a function |
912 | 912 | ||
913 | To ensure that generic code follows the above rules, this | 913 | To ensure that generic code follows the above rules, this |
914 | option forces all percpu variables to be defined as weak. | 914 | option forces all percpu variables to be defined as weak. |
915 | 915 | ||
916 | config LKDTM | 916 | config LKDTM |
917 | tristate "Linux Kernel Dump Test Tool Module" | 917 | tristate "Linux Kernel Dump Test Tool Module" |
918 | depends on DEBUG_FS | 918 | depends on DEBUG_FS |
919 | depends on BLOCK | 919 | depends on BLOCK |
920 | default n | 920 | default n |
921 | help | 921 | help |
922 | This module enables testing of the different dumping mechanisms by | 922 | This module enables testing of the different dumping mechanisms by |
923 | inducing system failures at predefined crash points. | 923 | inducing system failures at predefined crash points. |
924 | If you don't need it: say N | 924 | If you don't need it: say N |
925 | Choose M here to compile this code as a module. The module will be | 925 | Choose M here to compile this code as a module. The module will be |
926 | called lkdtm. | 926 | called lkdtm. |
927 | 927 | ||
928 | Documentation on how to use the module can be found in | 928 | Documentation on how to use the module can be found in |
929 | Documentation/fault-injection/provoke-crashes.txt | 929 | Documentation/fault-injection/provoke-crashes.txt |
930 | 930 | ||
931 | config CPU_NOTIFIER_ERROR_INJECT | 931 | config CPU_NOTIFIER_ERROR_INJECT |
932 | tristate "CPU notifier error injection module" | 932 | tristate "CPU notifier error injection module" |
933 | depends on HOTPLUG_CPU && DEBUG_KERNEL | 933 | depends on HOTPLUG_CPU && DEBUG_KERNEL |
934 | help | 934 | help |
935 | This option provides a kernel module that can be used to test | 935 | This option provides a kernel module that can be used to test |
936 | the error handling of the cpu notifiers | 936 | the error handling of the cpu notifiers |
937 | 937 | ||
938 | To compile this code as a module, choose M here: the module will | 938 | To compile this code as a module, choose M here: the module will |
939 | be called cpu-notifier-error-inject. | 939 | be called cpu-notifier-error-inject. |
940 | 940 | ||
941 | If unsure, say N. | 941 | If unsure, say N. |
942 | 942 | ||
943 | config FAULT_INJECTION | 943 | config FAULT_INJECTION |
944 | bool "Fault-injection framework" | 944 | bool "Fault-injection framework" |
945 | depends on DEBUG_KERNEL | 945 | depends on DEBUG_KERNEL |
946 | help | 946 | help |
947 | Provide fault-injection framework. | 947 | Provide fault-injection framework. |
948 | For more details, see Documentation/fault-injection/. | 948 | For more details, see Documentation/fault-injection/. |
949 | 949 | ||
950 | config FAILSLAB | 950 | config FAILSLAB |
951 | bool "Fault-injection capability for kmalloc" | 951 | bool "Fault-injection capability for kmalloc" |
952 | depends on FAULT_INJECTION | 952 | depends on FAULT_INJECTION |
953 | depends on SLAB || SLUB | 953 | depends on SLAB || SLUB |
954 | help | 954 | help |
955 | Provide fault-injection capability for kmalloc. | 955 | Provide fault-injection capability for kmalloc. |
956 | 956 | ||
957 | config FAIL_PAGE_ALLOC | 957 | config FAIL_PAGE_ALLOC |
958 | bool "Fault-injection capabilitiy for alloc_pages()" | 958 | bool "Fault-injection capabilitiy for alloc_pages()" |
959 | depends on FAULT_INJECTION | 959 | depends on FAULT_INJECTION |
960 | help | 960 | help |
961 | Provide fault-injection capability for alloc_pages(). | 961 | Provide fault-injection capability for alloc_pages(). |
962 | 962 | ||
963 | config FAIL_MAKE_REQUEST | 963 | config FAIL_MAKE_REQUEST |
964 | bool "Fault-injection capability for disk IO" | 964 | bool "Fault-injection capability for disk IO" |
965 | depends on FAULT_INJECTION && BLOCK | 965 | depends on FAULT_INJECTION && BLOCK |
966 | help | 966 | help |
967 | Provide fault-injection capability for disk IO. | 967 | Provide fault-injection capability for disk IO. |
968 | 968 | ||
969 | config FAIL_IO_TIMEOUT | 969 | config FAIL_IO_TIMEOUT |
970 | bool "Fault-injection capability for faking disk interrupts" | 970 | bool "Fault-injection capability for faking disk interrupts" |
971 | depends on FAULT_INJECTION && BLOCK | 971 | depends on FAULT_INJECTION && BLOCK |
972 | help | 972 | help |
973 | Provide fault-injection capability on end IO handling. This | 973 | Provide fault-injection capability on end IO handling. This |
974 | will make the block layer "forget" an interrupt as configured, | 974 | will make the block layer "forget" an interrupt as configured, |
975 | thus exercising the error handling. | 975 | thus exercising the error handling. |
976 | 976 | ||
977 | Only works with drivers that use the generic timeout handling, | 977 | Only works with drivers that use the generic timeout handling, |
978 | for others it wont do anything. | 978 | for others it wont do anything. |
979 | 979 | ||
980 | config FAULT_INJECTION_DEBUG_FS | 980 | config FAULT_INJECTION_DEBUG_FS |
981 | bool "Debugfs entries for fault-injection capabilities" | 981 | bool "Debugfs entries for fault-injection capabilities" |
982 | depends on FAULT_INJECTION && SYSFS && DEBUG_FS | 982 | depends on FAULT_INJECTION && SYSFS && DEBUG_FS |
983 | help | 983 | help |
984 | Enable configuration of fault-injection capabilities via debugfs. | 984 | Enable configuration of fault-injection capabilities via debugfs. |
985 | 985 | ||
986 | config FAULT_INJECTION_STACKTRACE_FILTER | 986 | config FAULT_INJECTION_STACKTRACE_FILTER |
987 | bool "stacktrace filter for fault-injection capabilities" | 987 | bool "stacktrace filter for fault-injection capabilities" |
988 | depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT | 988 | depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT |
989 | depends on !X86_64 | 989 | depends on !X86_64 |
990 | select STACKTRACE | 990 | select STACKTRACE |
991 | select FRAME_POINTER if !PPC && !S390 && !MICROBLAZE | 991 | select FRAME_POINTER if !PPC && !S390 && !MICROBLAZE |
992 | help | 992 | help |
993 | Provide stacktrace filter for fault-injection capabilities | 993 | Provide stacktrace filter for fault-injection capabilities |
994 | 994 | ||
995 | config LATENCYTOP | 995 | config LATENCYTOP |
996 | bool "Latency measuring infrastructure" | 996 | bool "Latency measuring infrastructure" |
997 | depends on HAVE_LATENCYTOP_SUPPORT | ||
998 | depends on DEBUG_KERNEL | ||
999 | depends on STACKTRACE_SUPPORT | ||
1000 | depends on PROC_FS | ||
997 | select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE | 1001 | select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE |
998 | select KALLSYMS | 1002 | select KALLSYMS |
999 | select KALLSYMS_ALL | 1003 | select KALLSYMS_ALL |
1000 | select STACKTRACE | 1004 | select STACKTRACE |
1001 | select SCHEDSTATS | 1005 | select SCHEDSTATS |
1002 | select SCHED_DEBUG | 1006 | select SCHED_DEBUG |
1003 | depends on HAVE_LATENCYTOP_SUPPORT | ||
1004 | help | 1007 | help |
1005 | Enable this option if you want to use the LatencyTOP tool | 1008 | Enable this option if you want to use the LatencyTOP tool |
1006 | to find out which userspace is blocking on what kernel operations. | 1009 | to find out which userspace is blocking on what kernel operations. |
1007 | 1010 | ||
1008 | config SYSCTL_SYSCALL_CHECK | 1011 | config SYSCTL_SYSCALL_CHECK |
1009 | bool "Sysctl checks" | 1012 | bool "Sysctl checks" |
1010 | depends on SYSCTL | 1013 | depends on SYSCTL |
1011 | ---help--- | 1014 | ---help--- |
1012 | sys_sysctl uses binary paths that have been found challenging | 1015 | sys_sysctl uses binary paths that have been found challenging |
1013 | to properly maintain and use. This enables checks that help | 1016 | to properly maintain and use. This enables checks that help |
1014 | you to keep things correct. | 1017 | you to keep things correct. |
1015 | 1018 | ||
1016 | source mm/Kconfig.debug | 1019 | source mm/Kconfig.debug |
1017 | source kernel/trace/Kconfig | 1020 | source kernel/trace/Kconfig |
1018 | 1021 | ||
1019 | config PROVIDE_OHCI1394_DMA_INIT | 1022 | config PROVIDE_OHCI1394_DMA_INIT |
1020 | bool "Remote debugging over FireWire early on boot" | 1023 | bool "Remote debugging over FireWire early on boot" |
1021 | depends on PCI && X86 | 1024 | depends on PCI && X86 |
1022 | help | 1025 | help |
1023 | If you want to debug problems which hang or crash the kernel early | 1026 | If you want to debug problems which hang or crash the kernel early |
1024 | on boot and the crashing machine has a FireWire port, you can use | 1027 | on boot and the crashing machine has a FireWire port, you can use |
1025 | this feature to remotely access the memory of the crashed machine | 1028 | this feature to remotely access the memory of the crashed machine |
1026 | over FireWire. This employs remote DMA as part of the OHCI1394 | 1029 | over FireWire. This employs remote DMA as part of the OHCI1394 |
1027 | specification which is now the standard for FireWire controllers. | 1030 | specification which is now the standard for FireWire controllers. |
1028 | 1031 | ||
1029 | With remote DMA, you can monitor the printk buffer remotely using | 1032 | With remote DMA, you can monitor the printk buffer remotely using |
1030 | firescope and access all memory below 4GB using fireproxy from gdb. | 1033 | firescope and access all memory below 4GB using fireproxy from gdb. |
1031 | Even controlling a kernel debugger is possible using remote DMA. | 1034 | Even controlling a kernel debugger is possible using remote DMA. |
1032 | 1035 | ||
1033 | Usage: | 1036 | Usage: |
1034 | 1037 | ||
1035 | If ohci1394_dma=early is used as boot parameter, it will initialize | 1038 | If ohci1394_dma=early is used as boot parameter, it will initialize |
1036 | all OHCI1394 controllers which are found in the PCI config space. | 1039 | all OHCI1394 controllers which are found in the PCI config space. |
1037 | 1040 | ||
1038 | As all changes to the FireWire bus such as enabling and disabling | 1041 | As all changes to the FireWire bus such as enabling and disabling |
1039 | devices cause a bus reset and thereby disable remote DMA for all | 1042 | devices cause a bus reset and thereby disable remote DMA for all |
1040 | devices, be sure to have the cable plugged and FireWire enabled on | 1043 | devices, be sure to have the cable plugged and FireWire enabled on |
1041 | the debugging host before booting the debug target for debugging. | 1044 | the debugging host before booting the debug target for debugging. |
1042 | 1045 | ||
1043 | This code (~1k) is freed after boot. By then, the firewire stack | 1046 | This code (~1k) is freed after boot. By then, the firewire stack |
1044 | in charge of the OHCI-1394 controllers should be used instead. | 1047 | in charge of the OHCI-1394 controllers should be used instead. |
1045 | 1048 | ||
1046 | See Documentation/debugging-via-ohci1394.txt for more information. | 1049 | See Documentation/debugging-via-ohci1394.txt for more information. |
1047 | 1050 | ||
1048 | config FIREWIRE_OHCI_REMOTE_DMA | 1051 | config FIREWIRE_OHCI_REMOTE_DMA |
1049 | bool "Remote debugging over FireWire with firewire-ohci" | 1052 | bool "Remote debugging over FireWire with firewire-ohci" |
1050 | depends on FIREWIRE_OHCI | 1053 | depends on FIREWIRE_OHCI |
1051 | help | 1054 | help |
1052 | This option lets you use the FireWire bus for remote debugging | 1055 | This option lets you use the FireWire bus for remote debugging |
1053 | with help of the firewire-ohci driver. It enables unfiltered | 1056 | with help of the firewire-ohci driver. It enables unfiltered |
1054 | remote DMA in firewire-ohci. | 1057 | remote DMA in firewire-ohci. |
1055 | See Documentation/debugging-via-ohci1394.txt for more information. | 1058 | See Documentation/debugging-via-ohci1394.txt for more information. |
1056 | 1059 | ||
1057 | If unsure, say N. | 1060 | If unsure, say N. |
1058 | 1061 | ||
1059 | config BUILD_DOCSRC | 1062 | config BUILD_DOCSRC |
1060 | bool "Build targets in Documentation/ tree" | 1063 | bool "Build targets in Documentation/ tree" |
1061 | depends on HEADERS_CHECK | 1064 | depends on HEADERS_CHECK |
1062 | help | 1065 | help |
1063 | This option attempts to build objects from the source files in the | 1066 | This option attempts to build objects from the source files in the |
1064 | kernel Documentation/ tree. | 1067 | kernel Documentation/ tree. |
1065 | 1068 | ||
1066 | Say N if you are unsure. | 1069 | Say N if you are unsure. |
1067 | 1070 | ||
1068 | config DYNAMIC_DEBUG | 1071 | config DYNAMIC_DEBUG |
1069 | bool "Enable dynamic printk() support" | 1072 | bool "Enable dynamic printk() support" |
1070 | default n | 1073 | default n |
1071 | depends on PRINTK | 1074 | depends on PRINTK |
1072 | depends on DEBUG_FS | 1075 | depends on DEBUG_FS |
1073 | help | 1076 | help |
1074 | 1077 | ||
1075 | Compiles debug level messages into the kernel, which would not | 1078 | Compiles debug level messages into the kernel, which would not |
1076 | otherwise be available at runtime. These messages can then be | 1079 | otherwise be available at runtime. These messages can then be |
1077 | enabled/disabled based on various levels of scope - per source file, | 1080 | enabled/disabled based on various levels of scope - per source file, |
1078 | function, module, format string, and line number. This mechanism | 1081 | function, module, format string, and line number. This mechanism |
1079 | implicitly enables all pr_debug() and dev_dbg() calls. The impact of | 1082 | implicitly enables all pr_debug() and dev_dbg() calls. The impact of |
1080 | this compile option is a larger kernel text size of about 2%. | 1083 | this compile option is a larger kernel text size of about 2%. |
1081 | 1084 | ||
1082 | Usage: | 1085 | Usage: |
1083 | 1086 | ||
1084 | Dynamic debugging is controlled via the 'dynamic_debug/control' file, | 1087 | Dynamic debugging is controlled via the 'dynamic_debug/control' file, |
1085 | which is contained in the 'debugfs' filesystem. Thus, the debugfs | 1088 | which is contained in the 'debugfs' filesystem. Thus, the debugfs |
1086 | filesystem must first be mounted before making use of this feature. | 1089 | filesystem must first be mounted before making use of this feature. |
1087 | We refer the control file as: <debugfs>/dynamic_debug/control. This | 1090 | We refer the control file as: <debugfs>/dynamic_debug/control. This |
1088 | file contains a list of the debug statements that can be enabled. The | 1091 | file contains a list of the debug statements that can be enabled. The |
1089 | format for each line of the file is: | 1092 | format for each line of the file is: |
1090 | 1093 | ||
1091 | filename:lineno [module]function flags format | 1094 | filename:lineno [module]function flags format |
1092 | 1095 | ||
1093 | filename : source file of the debug statement | 1096 | filename : source file of the debug statement |
1094 | lineno : line number of the debug statement | 1097 | lineno : line number of the debug statement |
1095 | module : module that contains the debug statement | 1098 | module : module that contains the debug statement |
1096 | function : function that contains the debug statement | 1099 | function : function that contains the debug statement |
1097 | flags : 'p' means the line is turned 'on' for printing | 1100 | flags : 'p' means the line is turned 'on' for printing |
1098 | format : the format used for the debug statement | 1101 | format : the format used for the debug statement |
1099 | 1102 | ||
1100 | From a live system: | 1103 | From a live system: |
1101 | 1104 | ||
1102 | nullarbor:~ # cat <debugfs>/dynamic_debug/control | 1105 | nullarbor:~ # cat <debugfs>/dynamic_debug/control |
1103 | # filename:lineno [module]function flags format | 1106 | # filename:lineno [module]function flags format |
1104 | fs/aio.c:222 [aio]__put_ioctx - "__put_ioctx:\040freeing\040%p\012" | 1107 | fs/aio.c:222 [aio]__put_ioctx - "__put_ioctx:\040freeing\040%p\012" |
1105 | fs/aio.c:248 [aio]ioctx_alloc - "ENOMEM:\040nr_events\040too\040high\012" | 1108 | fs/aio.c:248 [aio]ioctx_alloc - "ENOMEM:\040nr_events\040too\040high\012" |
1106 | fs/aio.c:1770 [aio]sys_io_cancel - "calling\040cancel\012" | 1109 | fs/aio.c:1770 [aio]sys_io_cancel - "calling\040cancel\012" |
1107 | 1110 | ||
1108 | Example usage: | 1111 | Example usage: |
1109 | 1112 | ||
1110 | // enable the message at line 1603 of file svcsock.c | 1113 | // enable the message at line 1603 of file svcsock.c |
1111 | nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > | 1114 | nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > |
1112 | <debugfs>/dynamic_debug/control | 1115 | <debugfs>/dynamic_debug/control |
1113 | 1116 | ||
1114 | // enable all the messages in file svcsock.c | 1117 | // enable all the messages in file svcsock.c |
1115 | nullarbor:~ # echo -n 'file svcsock.c +p' > | 1118 | nullarbor:~ # echo -n 'file svcsock.c +p' > |
1116 | <debugfs>/dynamic_debug/control | 1119 | <debugfs>/dynamic_debug/control |
1117 | 1120 | ||
1118 | // enable all the messages in the NFS server module | 1121 | // enable all the messages in the NFS server module |
1119 | nullarbor:~ # echo -n 'module nfsd +p' > | 1122 | nullarbor:~ # echo -n 'module nfsd +p' > |
1120 | <debugfs>/dynamic_debug/control | 1123 | <debugfs>/dynamic_debug/control |
1121 | 1124 | ||
1122 | // enable all 12 messages in the function svc_process() | 1125 | // enable all 12 messages in the function svc_process() |
1123 | nullarbor:~ # echo -n 'func svc_process +p' > | 1126 | nullarbor:~ # echo -n 'func svc_process +p' > |
1124 | <debugfs>/dynamic_debug/control | 1127 | <debugfs>/dynamic_debug/control |
1125 | 1128 | ||
1126 | // disable all 12 messages in the function svc_process() | 1129 | // disable all 12 messages in the function svc_process() |
1127 | nullarbor:~ # echo -n 'func svc_process -p' > | 1130 | nullarbor:~ # echo -n 'func svc_process -p' > |
1128 | <debugfs>/dynamic_debug/control | 1131 | <debugfs>/dynamic_debug/control |
1129 | 1132 | ||
1130 | See Documentation/dynamic-debug-howto.txt for additional information. | 1133 | See Documentation/dynamic-debug-howto.txt for additional information. |
1131 | 1134 | ||
1132 | config DMA_API_DEBUG | 1135 | config DMA_API_DEBUG |
1133 | bool "Enable debugging of DMA-API usage" | 1136 | bool "Enable debugging of DMA-API usage" |
1134 | depends on HAVE_DMA_API_DEBUG | 1137 | depends on HAVE_DMA_API_DEBUG |
1135 | help | 1138 | help |
1136 | Enable this option to debug the use of the DMA API by device drivers. | 1139 | Enable this option to debug the use of the DMA API by device drivers. |
1137 | With this option you will be able to detect common bugs in device | 1140 | With this option you will be able to detect common bugs in device |
1138 | drivers like double-freeing of DMA mappings or freeing mappings that | 1141 | drivers like double-freeing of DMA mappings or freeing mappings that |
1139 | were never allocated. | 1142 | were never allocated. |
1140 | This option causes a performance degredation. Use only if you want | 1143 | This option causes a performance degredation. Use only if you want |
1141 | to debug device drivers. If unsure, say N. | 1144 | to debug device drivers. If unsure, say N. |
1142 | 1145 | ||
1143 | config ATOMIC64_SELFTEST | 1146 | config ATOMIC64_SELFTEST |
1144 | bool "Perform an atomic64_t self-test at boot" | 1147 | bool "Perform an atomic64_t self-test at boot" |
1145 | help | 1148 | help |
1146 | Enable this option to test the atomic64_t functions at boot. | 1149 | Enable this option to test the atomic64_t functions at boot. |
1147 | 1150 | ||
1148 | If unsure, say N. | 1151 | If unsure, say N. |
1149 | 1152 | ||
1150 | source "samples/Kconfig" | 1153 | source "samples/Kconfig" |
1151 | 1154 | ||
1152 | source "lib/Kconfig.kgdb" | 1155 | source "lib/Kconfig.kgdb" |
1153 | 1156 | ||
1154 | source "lib/Kconfig.kmemcheck" | 1157 | source "lib/Kconfig.kmemcheck" |