Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1 | # |
Steven Rostedt | 606576c | 2008-10-06 19:06:12 -0400 | [diff] [blame] | 2 | # Architectures that offer an FUNCTION_TRACER implementation should |
| 3 | # select HAVE_FUNCTION_TRACER: |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 4 | # |
Frédéric Weisbecker | 2a3a4f6 | 2008-09-21 20:12:14 +0200 | [diff] [blame] | 5 | |
Török Edwin | 8d26487 | 2008-11-23 12:39:08 +0200 | [diff] [blame] | 6 | config USER_STACKTRACE_SUPPORT |
| 7 | bool |
| 8 | |
Frédéric Weisbecker | 2a3a4f6 | 2008-09-21 20:12:14 +0200 | [diff] [blame] | 9 | config NOP_TRACER |
| 10 | bool |
| 11 | |
Steven Rostedt | 78d904b | 2009-02-05 18:43:07 -0500 | [diff] [blame] | 12 | config HAVE_FTRACE_NMI_ENTER |
| 13 | bool |
Mike Frysinger | 555f386 | 2009-09-14 20:10:15 -0400 | [diff] [blame] | 14 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 15 | See Documentation/trace/ftrace-design.txt |
Steven Rostedt | 78d904b | 2009-02-05 18:43:07 -0500 | [diff] [blame] | 16 | |
Steven Rostedt | 606576c | 2008-10-06 19:06:12 -0400 | [diff] [blame] | 17 | config HAVE_FUNCTION_TRACER |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 18 | bool |
Mike Frysinger | 555f386 | 2009-09-14 20:10:15 -0400 | [diff] [blame] | 19 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 20 | See Documentation/trace/ftrace-design.txt |
Steven Rostedt | bc0c38d | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 21 | |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 22 | config HAVE_FUNCTION_GRAPH_TRACER |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 23 | bool |
Mike Frysinger | 555f386 | 2009-09-14 20:10:15 -0400 | [diff] [blame] | 24 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 25 | See Documentation/trace/ftrace-design.txt |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 26 | |
Steven Rostedt | 71e308a | 2009-06-18 12:45:08 -0400 | [diff] [blame] | 27 | config HAVE_FUNCTION_GRAPH_FP_TEST |
| 28 | bool |
| 29 | help |
Mike Frysinger | 0368897 | 2010-01-22 08:12:47 -0500 | [diff] [blame] | 30 | See Documentation/trace/ftrace-design.txt |
Steven Rostedt | 71e308a | 2009-06-18 12:45:08 -0400 | [diff] [blame] | 31 | |
Steven Rostedt | 677aa9f | 2008-05-17 00:01:36 -0400 | [diff] [blame] | 32 | config HAVE_DYNAMIC_FTRACE |
| 33 | bool |
Mike Frysinger | 555f386 | 2009-09-14 20:10:15 -0400 | [diff] [blame] | 34 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 35 | See Documentation/trace/ftrace-design.txt |
Steven Rostedt | 677aa9f | 2008-05-17 00:01:36 -0400 | [diff] [blame] | 36 | |
Masami Hiramatsu | 06aeaae | 2012-09-28 17:15:17 +0900 | [diff] [blame] | 37 | config HAVE_DYNAMIC_FTRACE_WITH_REGS |
| 38 | bool |
| 39 | |
Steven Rostedt | 8da3821 | 2008-08-14 15:45:07 -0400 | [diff] [blame] | 40 | config HAVE_FTRACE_MCOUNT_RECORD |
| 41 | bool |
Mike Frysinger | 555f386 | 2009-09-14 20:10:15 -0400 | [diff] [blame] | 42 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 43 | See Documentation/trace/ftrace-design.txt |
Steven Rostedt | 8da3821 | 2008-08-14 15:45:07 -0400 | [diff] [blame] | 44 | |
Josh Stone | 6670000 | 2009-08-24 14:43:11 -0700 | [diff] [blame] | 45 | config HAVE_SYSCALL_TRACEPOINTS |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 46 | bool |
Mike Frysinger | 555f386 | 2009-09-14 20:10:15 -0400 | [diff] [blame] | 47 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 48 | See Documentation/trace/ftrace-design.txt |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 49 | |
Steven Rostedt | a2546fa | 2011-02-09 13:15:59 -0500 | [diff] [blame] | 50 | config HAVE_FENTRY |
| 51 | bool |
| 52 | help |
| 53 | Arch supports the gcc options -pg with -mfentry |
| 54 | |
Steven Rostedt | cf4db25 | 2010-10-14 23:32:44 -0400 | [diff] [blame] | 55 | config HAVE_C_RECORDMCOUNT |
Steven Rostedt | 72441cb | 2010-10-13 17:12:30 -0400 | [diff] [blame] | 56 | bool |
| 57 | help |
| 58 | C version of recordmcount available? |
| 59 | |
Steven Rostedt | 352ad25 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 60 | config TRACER_MAX_TRACE |
| 61 | bool |
| 62 | |
Josh Triplett | ea632e9 | 2012-09-02 19:45:14 -0700 | [diff] [blame] | 63 | config TRACE_CLOCK |
| 64 | bool |
| 65 | |
Steven Rostedt | 7a8e76a | 2008-09-29 23:02:38 -0400 | [diff] [blame] | 66 | config RING_BUFFER |
| 67 | bool |
Josh Triplett | ea632e9 | 2012-09-02 19:45:14 -0700 | [diff] [blame] | 68 | select TRACE_CLOCK |
Steven Rostedt (Red Hat) | 2228768 | 2013-05-03 11:16:18 -0400 | [diff] [blame] | 69 | select IRQ_WORK |
Steven Rostedt | 7a8e76a | 2008-09-29 23:02:38 -0400 | [diff] [blame] | 70 | |
Steven Rostedt | 78d904b | 2009-02-05 18:43:07 -0500 | [diff] [blame] | 71 | config FTRACE_NMI_ENTER |
| 72 | bool |
| 73 | depends on HAVE_FTRACE_NMI_ENTER |
| 74 | default y |
| 75 | |
Tom Zanussi | 5f77a88 | 2009-04-08 03:14:01 -0500 | [diff] [blame] | 76 | config EVENT_TRACING |
Zhaolei | b11c53e | 2009-05-25 18:11:59 +0800 | [diff] [blame] | 77 | select CONTEXT_SWITCH_TRACER |
| 78 | bool |
| 79 | |
| 80 | config CONTEXT_SWITCH_TRACER |
Tom Zanussi | 5f77a88 | 2009-04-08 03:14:01 -0500 | [diff] [blame] | 81 | bool |
| 82 | |
Steven Rostedt | 85bac32 | 2009-09-04 14:24:40 -0400 | [diff] [blame] | 83 | config RING_BUFFER_ALLOW_SWAP |
| 84 | bool |
| 85 | help |
| 86 | Allow the use of ring_buffer_swap_cpu. |
| 87 | Adds a very slight overhead to tracing when enabled. |
| 88 | |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 89 | # All tracer options should select GENERIC_TRACER. For those options that are |
| 90 | # enabled by all tracers (context switch and event tracer) they select TRACING. |
| 91 | # This allows those options to appear when no other tracer is selected. But the |
| 92 | # options do not appear when something else selects it. We need the two options |
| 93 | # GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 94 | # hiding of the automatic options. |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 95 | |
Steven Rostedt | bc0c38d | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 96 | config TRACING |
| 97 | bool |
| 98 | select DEBUG_FS |
Steven Rostedt | 7a8e76a | 2008-09-29 23:02:38 -0400 | [diff] [blame] | 99 | select RING_BUFFER |
Al Viro | c2c8052 | 2008-10-31 19:50:41 +0000 | [diff] [blame] | 100 | select STACKTRACE if STACKTRACE_SUPPORT |
Ingo Molnar | 5f87f11 | 2008-07-23 14:15:22 +0200 | [diff] [blame] | 101 | select TRACEPOINTS |
Steven Rostedt | f3384b2 | 2008-10-29 11:15:57 -0400 | [diff] [blame] | 102 | select NOP_TRACER |
Frederic Weisbecker | 769b044 | 2009-03-06 17:21:49 +0100 | [diff] [blame] | 103 | select BINARY_PRINTF |
Tom Zanussi | 5f77a88 | 2009-04-08 03:14:01 -0500 | [diff] [blame] | 104 | select EVENT_TRACING |
Josh Triplett | ea632e9 | 2012-09-02 19:45:14 -0700 | [diff] [blame] | 105 | select TRACE_CLOCK |
Steven Rostedt | bc0c38d | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 106 | |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 107 | config GENERIC_TRACER |
| 108 | bool |
| 109 | select TRACING |
| 110 | |
Ingo Molnar | 40ada30 | 2009-03-05 21:19:55 +0100 | [diff] [blame] | 111 | # |
| 112 | # Minimum requirements an architecture has to meet for us to |
| 113 | # be able to offer generic tracing facilities: |
| 114 | # |
| 115 | config TRACING_SUPPORT |
| 116 | bool |
Anton Vorontsov | 45b9560 | 2009-03-24 01:07:24 +0300 | [diff] [blame] | 117 | # PPC32 has no irqflags tracing support, but it can use most of the |
| 118 | # tracers anyway, they were tested to build and work. Note that new |
| 119 | # exceptions to this list aren't welcomed, better implement the |
| 120 | # irqflags tracing for your architecture. |
| 121 | depends on TRACE_IRQFLAGS_SUPPORT || PPC32 |
Ingo Molnar | 40ada30 | 2009-03-05 21:19:55 +0100 | [diff] [blame] | 122 | depends on STACKTRACE_SUPPORT |
KOSAKI Motohiro | 422d3c7 | 2009-03-06 10:40:53 +0900 | [diff] [blame] | 123 | default y |
Ingo Molnar | 40ada30 | 2009-03-05 21:19:55 +0100 | [diff] [blame] | 124 | |
| 125 | if TRACING_SUPPORT |
| 126 | |
Steven Rostedt | 4ed9f07 | 2009-04-20 10:47:36 -0400 | [diff] [blame] | 127 | menuconfig FTRACE |
| 128 | bool "Tracers" |
Steven Rostedt | 65b7724 | 2009-05-07 12:49:27 -0400 | [diff] [blame] | 129 | default y if DEBUG_KERNEL |
Steven Rostedt | 4ed9f07 | 2009-04-20 10:47:36 -0400 | [diff] [blame] | 130 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 131 | Enable the kernel tracing infrastructure. |
Steven Rostedt | 4ed9f07 | 2009-04-20 10:47:36 -0400 | [diff] [blame] | 132 | |
| 133 | if FTRACE |
Peter Zijlstra | 17d80fd | 2008-10-21 16:31:18 +0200 | [diff] [blame] | 134 | |
Steven Rostedt | 606576c | 2008-10-06 19:06:12 -0400 | [diff] [blame] | 135 | config FUNCTION_TRACER |
Steven Rostedt | 1b29b01 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 136 | bool "Kernel Function Tracer" |
Steven Rostedt | 606576c | 2008-10-06 19:06:12 -0400 | [diff] [blame] | 137 | depends on HAVE_FUNCTION_TRACER |
Steven Rostedt | 4d7a077 | 2009-02-18 22:06:18 -0500 | [diff] [blame] | 138 | select KALLSYMS |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 139 | select GENERIC_TRACER |
Steven Rostedt | 35e8e30 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 140 | select CONTEXT_SWITCH_TRACER |
Steven Rostedt | 1b29b01 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 141 | help |
| 142 | Enable the kernel to trace every kernel function. This is done |
| 143 | by using a compiler feature to insert a small, 5-byte No-Operation |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 144 | instruction at the beginning of every kernel function, which NOP |
Steven Rostedt | 1b29b01 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 145 | sequence is then dynamically patched into a tracer call when |
| 146 | tracing is enabled by the administrator. If it's runtime disabled |
| 147 | (the bootup default), then the overhead of the instructions is very |
| 148 | small and not measurable even in micro-benchmarks. |
Steven Rostedt | 35e8e30 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 149 | |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 150 | config FUNCTION_GRAPH_TRACER |
| 151 | bool "Kernel Function Graph Tracer" |
| 152 | depends on HAVE_FUNCTION_GRAPH_TRACER |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 153 | depends on FUNCTION_TRACER |
Steven Rostedt | eb4a037 | 2009-06-18 12:53:21 -0400 | [diff] [blame] | 154 | depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE |
Ingo Molnar | 764f3b9 | 2008-12-03 10:33:58 +0100 | [diff] [blame] | 155 | default y |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 156 | help |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 157 | Enable the kernel to trace a function at both its return |
| 158 | and its entry. |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 159 | Its first purpose is to trace the duration of functions and |
| 160 | draw a call graph for each thread with some information like |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 161 | the return value. This is done by setting the current return |
Matt LaPlante | 692105b | 2009-01-26 11:12:25 +0100 | [diff] [blame] | 162 | address on the current task structure into a stack of calls. |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 163 | |
Steven Rostedt | bac429f | 2009-03-20 12:50:56 -0400 | [diff] [blame] | 164 | |
Steven Rostedt | 81d68a9 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 165 | config IRQSOFF_TRACER |
| 166 | bool "Interrupts-off Latency Tracer" |
| 167 | default n |
| 168 | depends on TRACE_IRQFLAGS_SUPPORT |
John Stultz | 592913e | 2010-07-13 17:56:20 -0700 | [diff] [blame] | 169 | depends on !ARCH_USES_GETTIMEOFFSET |
Steven Rostedt | 81d68a9 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 170 | select TRACE_IRQFLAGS |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 171 | select GENERIC_TRACER |
Steven Rostedt | 81d68a9 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 172 | select TRACER_MAX_TRACE |
Steven Rostedt | 85bac32 | 2009-09-04 14:24:40 -0400 | [diff] [blame] | 173 | select RING_BUFFER_ALLOW_SWAP |
Steven Rostedt (Red Hat) | 22cffc2 | 2013-03-05 07:30:24 -0500 | [diff] [blame] | 174 | select TRACER_SNAPSHOT |
Steven Rostedt (Red Hat) | 0b85ffc | 2013-03-05 14:50:23 -0500 | [diff] [blame] | 175 | select TRACER_SNAPSHOT_PER_CPU_SWAP |
Steven Rostedt | 81d68a9 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 176 | help |
| 177 | This option measures the time spent in irqs-off critical |
| 178 | sections, with microsecond accuracy. |
| 179 | |
| 180 | The default measurement method is a maximum search, which is |
| 181 | disabled by default and can be runtime (re-)started |
| 182 | via: |
| 183 | |
GeunSik Lim | 156f5a7 | 2009-06-02 15:01:37 +0900 | [diff] [blame] | 184 | echo 0 > /sys/kernel/debug/tracing/tracing_max_latency |
Steven Rostedt | 81d68a9 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 185 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 186 | (Note that kernel size and overhead increase with this option |
Steven Rostedt | 6cd8a4b | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 187 | enabled. This option and the preempt-off timing option can be |
| 188 | used together or separately.) |
| 189 | |
| 190 | config PREEMPT_TRACER |
| 191 | bool "Preemption-off Latency Tracer" |
| 192 | default n |
John Stultz | 592913e | 2010-07-13 17:56:20 -0700 | [diff] [blame] | 193 | depends on !ARCH_USES_GETTIMEOFFSET |
Steven Rostedt | 6cd8a4b | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 194 | depends on PREEMPT |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 195 | select GENERIC_TRACER |
Steven Rostedt | 6cd8a4b | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 196 | select TRACER_MAX_TRACE |
Steven Rostedt | 85bac32 | 2009-09-04 14:24:40 -0400 | [diff] [blame] | 197 | select RING_BUFFER_ALLOW_SWAP |
Steven Rostedt (Red Hat) | 22cffc2 | 2013-03-05 07:30:24 -0500 | [diff] [blame] | 198 | select TRACER_SNAPSHOT |
Steven Rostedt (Red Hat) | 0b85ffc | 2013-03-05 14:50:23 -0500 | [diff] [blame] | 199 | select TRACER_SNAPSHOT_PER_CPU_SWAP |
Steven Rostedt | 6cd8a4b | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 200 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 201 | This option measures the time spent in preemption-off critical |
Steven Rostedt | 6cd8a4b | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 202 | sections, with microsecond accuracy. |
| 203 | |
| 204 | The default measurement method is a maximum search, which is |
| 205 | disabled by default and can be runtime (re-)started |
| 206 | via: |
| 207 | |
GeunSik Lim | 156f5a7 | 2009-06-02 15:01:37 +0900 | [diff] [blame] | 208 | echo 0 > /sys/kernel/debug/tracing/tracing_max_latency |
Steven Rostedt | 6cd8a4b | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 209 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 210 | (Note that kernel size and overhead increase with this option |
Steven Rostedt | 6cd8a4b | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 211 | enabled. This option and the irqs-off timing option can be |
| 212 | used together or separately.) |
| 213 | |
Steven Rostedt | 352ad25 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 214 | config SCHED_TRACER |
| 215 | bool "Scheduling Latency Tracer" |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 216 | select GENERIC_TRACER |
Steven Rostedt | 352ad25 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 217 | select CONTEXT_SWITCH_TRACER |
| 218 | select TRACER_MAX_TRACE |
Steven Rostedt (Red Hat) | 22cffc2 | 2013-03-05 07:30:24 -0500 | [diff] [blame] | 219 | select TRACER_SNAPSHOT |
Steven Rostedt | 352ad25 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 220 | help |
| 221 | This tracer tracks the latency of the highest priority task |
| 222 | to be scheduled in, starting from the point it has woken up. |
| 223 | |
Steven Rostedt | 897f17a | 2009-05-28 16:31:21 -0400 | [diff] [blame] | 224 | config ENABLE_DEFAULT_TRACERS |
| 225 | bool "Trace process context switches and events" |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 226 | depends on !GENERIC_TRACER |
Steven Rostedt | b77e38a | 2009-02-24 10:21:36 -0500 | [diff] [blame] | 227 | select TRACING |
| 228 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 229 | This tracer hooks to various trace points in the kernel, |
Steven Rostedt | b77e38a | 2009-02-24 10:21:36 -0500 | [diff] [blame] | 230 | allowing the user to pick and choose which trace point they |
Steven Rostedt | 897f17a | 2009-05-28 16:31:21 -0400 | [diff] [blame] | 231 | want to trace. It also includes the sched_switch tracer plugin. |
Steven Rostedt | a7abe97 | 2009-04-20 10:59:34 -0400 | [diff] [blame] | 232 | |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 233 | config FTRACE_SYSCALLS |
| 234 | bool "Trace syscalls" |
Josh Stone | 6670000 | 2009-08-24 14:43:11 -0700 | [diff] [blame] | 235 | depends on HAVE_SYSCALL_TRACEPOINTS |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 236 | select GENERIC_TRACER |
Frederic Weisbecker | 0ea1c41 | 2009-03-15 22:10:38 +0100 | [diff] [blame] | 237 | select KALLSYMS |
Frederic Weisbecker | ee08c6e | 2009-03-07 05:52:59 +0100 | [diff] [blame] | 238 | help |
| 239 | Basic tracer to catch the syscall entry and exit events. |
| 240 | |
Hiraku Toyooka | debdd57 | 2012-12-26 11:53:00 +0900 | [diff] [blame] | 241 | config TRACER_SNAPSHOT |
| 242 | bool "Create a snapshot trace buffer" |
| 243 | select TRACER_MAX_TRACE |
| 244 | help |
| 245 | Allow tracing users to take snapshot of the current buffer using the |
| 246 | ftrace interface, e.g.: |
| 247 | |
| 248 | echo 1 > /sys/kernel/debug/tracing/snapshot |
| 249 | cat snapshot |
| 250 | |
Steven Rostedt (Red Hat) | 0b85ffc | 2013-03-05 14:50:23 -0500 | [diff] [blame] | 251 | config TRACER_SNAPSHOT_PER_CPU_SWAP |
| 252 | bool "Allow snapshot to swap per CPU" |
| 253 | depends on TRACER_SNAPSHOT |
| 254 | select RING_BUFFER_ALLOW_SWAP |
| 255 | help |
| 256 | Allow doing a snapshot of a single CPU buffer instead of a |
| 257 | full swap (all buffers). If this is set, then the following is |
| 258 | allowed: |
| 259 | |
| 260 | echo 1 > /sys/kernel/debug/tracing/per_cpu/cpu2/snapshot |
| 261 | |
| 262 | After which, only the tracing buffer for CPU 2 was swapped with |
| 263 | the main tracing buffer, and the other CPU buffers remain the same. |
| 264 | |
| 265 | When this is enabled, this adds a little more overhead to the |
| 266 | trace recording, as it needs to add some checks to synchronize |
| 267 | recording with swaps. But this does not affect the performance |
| 268 | of the overall system. This is enabled by default when the preempt |
| 269 | or irq latency tracers are enabled, as those need to swap as well |
| 270 | and already adds the overhead (plus a lot more). |
| 271 | |
Steven Rostedt | 2ed84ee | 2008-11-12 15:24:24 -0500 | [diff] [blame] | 272 | config TRACE_BRANCH_PROFILING |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 273 | bool |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 274 | select GENERIC_TRACER |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 275 | |
| 276 | choice |
| 277 | prompt "Branch Profiling" |
| 278 | default BRANCH_PROFILE_NONE |
| 279 | help |
| 280 | The branch profiling is a software profiler. It will add hooks |
| 281 | into the C conditionals to test which path a branch takes. |
| 282 | |
| 283 | The likely/unlikely profiler only looks at the conditions that |
| 284 | are annotated with a likely or unlikely macro. |
| 285 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 286 | The "all branch" profiler will profile every if-statement in the |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 287 | kernel. This profiler will also enable the likely/unlikely |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 288 | profiler. |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 289 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 290 | Either of the above profilers adds a bit of overhead to the system. |
| 291 | If unsure, choose "No branch profiling". |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 292 | |
| 293 | config BRANCH_PROFILE_NONE |
| 294 | bool "No branch profiling" |
| 295 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 296 | No branch profiling. Branch profiling adds a bit of overhead. |
| 297 | Only enable it if you want to analyse the branching behavior. |
| 298 | Otherwise keep it disabled. |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 299 | |
| 300 | config PROFILE_ANNOTATED_BRANCHES |
| 301 | bool "Trace likely/unlikely profiler" |
| 302 | select TRACE_BRANCH_PROFILING |
Steven Rostedt | 1f0d69a | 2008-11-12 00:14:39 -0500 | [diff] [blame] | 303 | help |
Masanari Iida | 59bf896 | 2012-04-18 00:01:21 +0900 | [diff] [blame] | 304 | This tracer profiles all likely and unlikely macros |
Steven Rostedt | 1f0d69a | 2008-11-12 00:14:39 -0500 | [diff] [blame] | 305 | in the kernel. It will display the results in: |
| 306 | |
David Rientjes | 13e5bef | 2011-03-16 17:17:08 -0700 | [diff] [blame] | 307 | /sys/kernel/debug/tracing/trace_stat/branch_annotated |
Steven Rostedt | 1f0d69a | 2008-11-12 00:14:39 -0500 | [diff] [blame] | 308 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 309 | Note: this will add a significant overhead; only turn this |
Steven Rostedt | 1f0d69a | 2008-11-12 00:14:39 -0500 | [diff] [blame] | 310 | on if you need to profile the system's use of these macros. |
| 311 | |
Steven Rostedt | 2bcd521 | 2008-11-21 01:30:54 -0500 | [diff] [blame] | 312 | config PROFILE_ALL_BRANCHES |
| 313 | bool "Profile all if conditionals" |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 314 | select TRACE_BRANCH_PROFILING |
Steven Rostedt | 2bcd521 | 2008-11-21 01:30:54 -0500 | [diff] [blame] | 315 | help |
| 316 | This tracer profiles all branch conditions. Every if () |
| 317 | taken in the kernel is recorded whether it hit or miss. |
| 318 | The results will be displayed in: |
| 319 | |
David Rientjes | 13e5bef | 2011-03-16 17:17:08 -0700 | [diff] [blame] | 320 | /sys/kernel/debug/tracing/trace_stat/branch_all |
Steven Rostedt | 2bcd521 | 2008-11-21 01:30:54 -0500 | [diff] [blame] | 321 | |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 322 | This option also enables the likely/unlikely profiler. |
| 323 | |
Steven Rostedt | 2bcd521 | 2008-11-21 01:30:54 -0500 | [diff] [blame] | 324 | This configuration, when enabled, will impose a great overhead |
| 325 | on the system. This should only be enabled when the system |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 326 | is to be analyzed in much detail. |
Steven Rostedt | 9ae5b87 | 2009-04-20 10:27:58 -0400 | [diff] [blame] | 327 | endchoice |
Steven Rostedt | 2bcd521 | 2008-11-21 01:30:54 -0500 | [diff] [blame] | 328 | |
Steven Rostedt | 2ed84ee | 2008-11-12 15:24:24 -0500 | [diff] [blame] | 329 | config TRACING_BRANCHES |
Steven Rostedt | 52f232c | 2008-11-12 00:14:40 -0500 | [diff] [blame] | 330 | bool |
| 331 | help |
| 332 | Selected by tracers that will trace the likely and unlikely |
| 333 | conditions. This prevents the tracers themselves from being |
| 334 | profiled. Profiling the tracing infrastructure can only happen |
| 335 | when the likelys and unlikelys are not being traced. |
| 336 | |
Steven Rostedt | 2ed84ee | 2008-11-12 15:24:24 -0500 | [diff] [blame] | 337 | config BRANCH_TRACER |
Steven Rostedt | 52f232c | 2008-11-12 00:14:40 -0500 | [diff] [blame] | 338 | bool "Trace likely/unlikely instances" |
Steven Rostedt | 2ed84ee | 2008-11-12 15:24:24 -0500 | [diff] [blame] | 339 | depends on TRACE_BRANCH_PROFILING |
| 340 | select TRACING_BRANCHES |
Steven Rostedt | 52f232c | 2008-11-12 00:14:40 -0500 | [diff] [blame] | 341 | help |
| 342 | This traces the events of likely and unlikely condition |
| 343 | calls in the kernel. The difference between this and the |
| 344 | "Trace likely/unlikely profiler" is that this is not a |
| 345 | histogram of the callers, but actually places the calling |
| 346 | events into a running trace buffer to see when and where the |
| 347 | events happened, as well as their results. |
| 348 | |
| 349 | Say N if unsure. |
| 350 | |
Steven Rostedt | e5a81b6 | 2008-08-27 23:31:01 -0400 | [diff] [blame] | 351 | config STACK_TRACER |
| 352 | bool "Trace max stack" |
Steven Rostedt | 606576c | 2008-10-06 19:06:12 -0400 | [diff] [blame] | 353 | depends on HAVE_FUNCTION_TRACER |
Steven Rostedt | 606576c | 2008-10-06 19:06:12 -0400 | [diff] [blame] | 354 | select FUNCTION_TRACER |
Steven Rostedt | e5a81b6 | 2008-08-27 23:31:01 -0400 | [diff] [blame] | 355 | select STACKTRACE |
Steven Rostedt | 4d7a077 | 2009-02-18 22:06:18 -0500 | [diff] [blame] | 356 | select KALLSYMS |
Steven Rostedt | e5a81b6 | 2008-08-27 23:31:01 -0400 | [diff] [blame] | 357 | help |
Ingo Molnar | 4519d9e | 2008-10-14 14:15:43 +0200 | [diff] [blame] | 358 | This special tracer records the maximum stack footprint of the |
GeunSik Lim | 156f5a7 | 2009-06-02 15:01:37 +0900 | [diff] [blame] | 359 | kernel and displays it in /sys/kernel/debug/tracing/stack_trace. |
Ingo Molnar | 4519d9e | 2008-10-14 14:15:43 +0200 | [diff] [blame] | 360 | |
| 361 | This tracer works by hooking into every function call that the |
| 362 | kernel executes, and keeping a maximum stack depth value and |
Steven Rostedt | f38f1d2 | 2008-12-16 23:06:40 -0500 | [diff] [blame] | 363 | stack-trace saved. If this is configured with DYNAMIC_FTRACE |
| 364 | then it will not have any overhead while the stack tracer |
| 365 | is disabled. |
| 366 | |
| 367 | To enable the stack tracer on bootup, pass in 'stacktrace' |
| 368 | on the kernel command line. |
| 369 | |
| 370 | The stack tracer can also be enabled or disabled via the |
| 371 | sysctl kernel.stack_tracer_enabled |
Ingo Molnar | 4519d9e | 2008-10-14 14:15:43 +0200 | [diff] [blame] | 372 | |
| 373 | Say N if unsure. |
Steven Rostedt | e5a81b6 | 2008-08-27 23:31:01 -0400 | [diff] [blame] | 374 | |
Frederic Weisbecker | 2db270a | 2009-02-07 20:46:45 +0100 | [diff] [blame] | 375 | config BLK_DEV_IO_TRACE |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 376 | bool "Support for tracing block IO actions" |
Frederic Weisbecker | 2db270a | 2009-02-07 20:46:45 +0100 | [diff] [blame] | 377 | depends on SYSFS |
Ingo Molnar | 1dfba05 | 2009-02-09 12:06:54 +0100 | [diff] [blame] | 378 | depends on BLOCK |
Frederic Weisbecker | 2db270a | 2009-02-07 20:46:45 +0100 | [diff] [blame] | 379 | select RELAY |
| 380 | select DEBUG_FS |
| 381 | select TRACEPOINTS |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 382 | select GENERIC_TRACER |
Frederic Weisbecker | 2db270a | 2009-02-07 20:46:45 +0100 | [diff] [blame] | 383 | select STACKTRACE |
| 384 | help |
| 385 | Say Y here if you want to be able to trace the block layer actions |
| 386 | on a given queue. Tracing allows you to see any traffic happening |
| 387 | on a block device queue. For more information (and the userspace |
| 388 | support tools needed), fetch the blktrace tools from: |
| 389 | |
| 390 | git://git.kernel.dk/blktrace.git |
| 391 | |
| 392 | Tracing also is possible using the ftrace interface, e.g.: |
| 393 | |
| 394 | echo 1 > /sys/block/sda/sda1/trace/enable |
| 395 | echo blk > /sys/kernel/debug/tracing/current_tracer |
| 396 | cat /sys/kernel/debug/tracing/trace_pipe |
| 397 | |
| 398 | If unsure, say N. |
Frederic Weisbecker | 36994e5 | 2008-12-29 13:42:23 -0800 | [diff] [blame] | 399 | |
Masami Hiramatsu | 77b44d1 | 2009-11-03 19:12:47 -0500 | [diff] [blame] | 400 | config KPROBE_EVENT |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 401 | depends on KPROBES |
Heiko Carstens | f850c30c | 2010-02-10 17:25:17 +0100 | [diff] [blame] | 402 | depends on HAVE_REGS_AND_STACK_ACCESS_API |
Masami Hiramatsu | 77b44d1 | 2009-11-03 19:12:47 -0500 | [diff] [blame] | 403 | bool "Enable kprobes-based dynamic events" |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 404 | select TRACING |
Srikar Dronamraju | 8ab83f5 | 2012-04-09 14:41:44 +0530 | [diff] [blame] | 405 | select PROBE_EVENTS |
Masami Hiramatsu | 77b44d1 | 2009-11-03 19:12:47 -0500 | [diff] [blame] | 406 | default y |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 407 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 408 | This allows the user to add tracing events (similar to tracepoints) |
| 409 | on the fly via the ftrace interface. See |
| 410 | Documentation/trace/kprobetrace.txt for more details. |
Masami Hiramatsu | 77b44d1 | 2009-11-03 19:12:47 -0500 | [diff] [blame] | 411 | |
| 412 | Those events can be inserted wherever kprobes can probe, and record |
| 413 | various register and memory values. |
| 414 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 415 | This option is also required by perf-probe subcommand of perf tools. |
| 416 | If you want to use perf tools, this option is strongly recommended. |
Masami Hiramatsu | 413d37d | 2009-08-13 16:35:11 -0400 | [diff] [blame] | 417 | |
Srikar Dronamraju | f3f096c | 2012-04-11 16:00:43 +0530 | [diff] [blame] | 418 | config UPROBE_EVENT |
| 419 | bool "Enable uprobes-based dynamic events" |
| 420 | depends on ARCH_SUPPORTS_UPROBES |
| 421 | depends on MMU |
David A. Long | 09294e3 | 2014-03-07 10:32:22 -0500 | [diff] [blame] | 422 | depends on PERF_EVENTS |
Srikar Dronamraju | f3f096c | 2012-04-11 16:00:43 +0530 | [diff] [blame] | 423 | select UPROBES |
| 424 | select PROBE_EVENTS |
| 425 | select TRACING |
| 426 | default n |
| 427 | help |
| 428 | This allows the user to add tracing events on top of userspace |
| 429 | dynamic events (similar to tracepoints) on the fly via the trace |
| 430 | events interface. Those events can be inserted wherever uprobes |
| 431 | can probe, and record various registers. |
| 432 | This option is required if you plan to use perf-probe subcommand |
| 433 | of perf tools on user space applications. |
| 434 | |
Ingo Molnar | e1abf2c | 2015-04-02 15:51:39 +0200 | [diff] [blame] | 435 | config BPF_EVENTS |
| 436 | depends on BPF_SYSCALL |
| 437 | depends on KPROBE_EVENT |
| 438 | bool |
| 439 | default y |
| 440 | help |
| 441 | This allows the user to attach BPF programs to kprobe events. |
| 442 | |
Srikar Dronamraju | 8ab83f5 | 2012-04-09 14:41:44 +0530 | [diff] [blame] | 443 | config PROBE_EVENTS |
| 444 | def_bool n |
| 445 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 446 | config DYNAMIC_FTRACE |
Steven Rostedt | db05021 | 2013-02-27 21:48:09 -0500 | [diff] [blame] | 447 | bool "enable/disable function tracing dynamically" |
Steven Rostedt | 606576c | 2008-10-06 19:06:12 -0400 | [diff] [blame] | 448 | depends on FUNCTION_TRACER |
Steven Rostedt | 677aa9f | 2008-05-17 00:01:36 -0400 | [diff] [blame] | 449 | depends on HAVE_DYNAMIC_FTRACE |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 450 | default y |
| 451 | help |
Steven Rostedt | db05021 | 2013-02-27 21:48:09 -0500 | [diff] [blame] | 452 | This option will modify all the calls to function tracing |
| 453 | dynamically (will patch them out of the binary image and |
| 454 | replace them with a No-Op instruction) on boot up. During |
| 455 | compile time, a table is made of all the locations that ftrace |
| 456 | can function trace, and this table is linked into the kernel |
| 457 | image. When this is enabled, functions can be individually |
| 458 | enabled, and the functions not enabled will not affect |
| 459 | performance of the system. |
| 460 | |
| 461 | See the files in /sys/kernel/debug/tracing: |
| 462 | available_filter_functions |
| 463 | set_ftrace_filter |
| 464 | set_ftrace_notrace |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 465 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 466 | This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but |
| 467 | otherwise has native performance as long as no tracing is active. |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 468 | |
Masami Hiramatsu | 06aeaae | 2012-09-28 17:15:17 +0900 | [diff] [blame] | 469 | config DYNAMIC_FTRACE_WITH_REGS |
| 470 | def_bool y |
| 471 | depends on DYNAMIC_FTRACE |
| 472 | depends on HAVE_DYNAMIC_FTRACE_WITH_REGS |
| 473 | |
Steven Rostedt | bac429f | 2009-03-20 12:50:56 -0400 | [diff] [blame] | 474 | config FUNCTION_PROFILER |
| 475 | bool "Kernel function profiler" |
Steven Rostedt | 493762f | 2009-03-23 17:12:36 -0400 | [diff] [blame] | 476 | depends on FUNCTION_TRACER |
Steven Rostedt | bac429f | 2009-03-20 12:50:56 -0400 | [diff] [blame] | 477 | default n |
| 478 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 479 | This option enables the kernel function profiler. A file is created |
| 480 | in debugfs called function_profile_enabled which defaults to zero. |
| 481 | When a 1 is echoed into this file profiling begins, and when a |
| 482 | zero is entered, profiling stops. A "functions" file is created in |
| 483 | the trace_stats directory; this file shows the list of functions that |
| 484 | have been hit and their counters. |
Steven Rostedt | bac429f | 2009-03-20 12:50:56 -0400 | [diff] [blame] | 485 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 486 | If in doubt, say N. |
Steven Rostedt | bac429f | 2009-03-20 12:50:56 -0400 | [diff] [blame] | 487 | |
Steven Rostedt | 8da3821 | 2008-08-14 15:45:07 -0400 | [diff] [blame] | 488 | config FTRACE_MCOUNT_RECORD |
| 489 | def_bool y |
| 490 | depends on DYNAMIC_FTRACE |
| 491 | depends on HAVE_FTRACE_MCOUNT_RECORD |
| 492 | |
Steven Rostedt | 60a1177 | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 493 | config FTRACE_SELFTEST |
| 494 | bool |
| 495 | |
| 496 | config FTRACE_STARTUP_TEST |
| 497 | bool "Perform a startup test on ftrace" |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 498 | depends on GENERIC_TRACER |
Steven Rostedt | 60a1177 | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 499 | select FTRACE_SELFTEST |
| 500 | help |
| 501 | This option performs a series of startup tests on ftrace. On bootup |
| 502 | a series of tests are made to verify that the tracer is |
| 503 | functioning properly. It will do tests on all the configured |
| 504 | tracers of ftrace. |
Peter Zijlstra | 17d80fd | 2008-10-21 16:31:18 +0200 | [diff] [blame] | 505 | |
Steven Rostedt | 1f5a6b4 | 2009-09-14 11:58:24 -0400 | [diff] [blame] | 506 | config EVENT_TRACE_TEST_SYSCALLS |
| 507 | bool "Run selftest on syscall events" |
| 508 | depends on FTRACE_STARTUP_TEST |
| 509 | help |
| 510 | This option will also enable testing every syscall event. |
| 511 | It only enables the event and disables it and runs various loads |
| 512 | with the event enabled. This adds a bit more time for kernel boot |
| 513 | up since it runs this on every system call defined. |
| 514 | |
| 515 | TBD - enable a way to actually call the syscalls as we test their |
| 516 | events |
| 517 | |
Pekka Paalanen | fe6f90e | 2009-01-03 21:23:51 +0200 | [diff] [blame] | 518 | config MMIOTRACE |
| 519 | bool "Memory mapped IO tracing" |
Ingo Molnar | 40ada30 | 2009-03-05 21:19:55 +0100 | [diff] [blame] | 520 | depends on HAVE_MMIOTRACE_SUPPORT && PCI |
Steven Rostedt | 5e0a093 | 2009-05-28 15:50:13 -0400 | [diff] [blame] | 521 | select GENERIC_TRACER |
Pekka Paalanen | fe6f90e | 2009-01-03 21:23:51 +0200 | [diff] [blame] | 522 | help |
| 523 | Mmiotrace traces Memory Mapped I/O access and is meant for |
| 524 | debugging and reverse engineering. It is called from the ioremap |
| 525 | implementation and works via page faults. Tracing is disabled by |
| 526 | default and can be enabled at run-time. |
| 527 | |
Li Zefan | 4d1f437 | 2009-04-10 08:48:36 +0800 | [diff] [blame] | 528 | See Documentation/trace/mmiotrace.txt. |
Pekka Paalanen | fe6f90e | 2009-01-03 21:23:51 +0200 | [diff] [blame] | 529 | If you are not helping to develop drivers, say N. |
| 530 | |
| 531 | config MMIOTRACE_TEST |
| 532 | tristate "Test module for mmiotrace" |
| 533 | depends on MMIOTRACE && m |
| 534 | help |
| 535 | This is a dumb module for testing mmiotrace. It is very dangerous |
| 536 | as it will write garbage to IO memory starting at a given address. |
| 537 | However, it should be safe to use on e.g. unused portion of VRAM. |
| 538 | |
| 539 | Say N, unless you absolutely know what you are doing. |
| 540 | |
Steven Rostedt (Red Hat) | 81dc9f0 | 2014-05-29 22:49:07 -0400 | [diff] [blame] | 541 | config TRACEPOINT_BENCHMARK |
| 542 | bool "Add tracepoint that benchmarks tracepoints" |
| 543 | help |
| 544 | This option creates the tracepoint "benchmark:benchmark_event". |
| 545 | When the tracepoint is enabled, it kicks off a kernel thread that |
| 546 | goes into an infinite loop (calling cond_sched() to let other tasks |
| 547 | run), and calls the tracepoint. Each iteration will record the time |
| 548 | it took to write to the tracepoint and the next iteration that |
| 549 | data will be passed to the tracepoint itself. That is, the tracepoint |
| 550 | will report the time it took to do the previous tracepoint. |
| 551 | The string written to the tracepoint is a static string of 128 bytes |
| 552 | to keep the time the same. The initial string is simply a write of |
| 553 | "START". The second string records the cold cache time of the first |
| 554 | write which is not added to the rest of the calculations. |
| 555 | |
| 556 | As it is a tight loop, it benchmarks as hot cache. That's fine because |
| 557 | we care most about hot paths that are probably in cache already. |
| 558 | |
| 559 | An example of the output: |
| 560 | |
| 561 | START |
| 562 | first=3672 [COLD CACHED] |
| 563 | last=632 first=3672 max=632 min=632 avg=316 std=446 std^2=199712 |
| 564 | last=278 first=3672 max=632 min=278 avg=303 std=316 std^2=100337 |
| 565 | last=277 first=3672 max=632 min=277 avg=296 std=258 std^2=67064 |
| 566 | last=273 first=3672 max=632 min=273 avg=292 std=224 std^2=50411 |
| 567 | last=273 first=3672 max=632 min=273 avg=288 std=200 std^2=40389 |
| 568 | last=281 first=3672 max=632 min=273 avg=287 std=183 std^2=33666 |
| 569 | |
| 570 | |
Steven Rostedt | 5092dbc | 2009-05-05 22:47:18 -0400 | [diff] [blame] | 571 | config RING_BUFFER_BENCHMARK |
| 572 | tristate "Ring buffer benchmark stress tester" |
| 573 | depends on RING_BUFFER |
| 574 | help |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 575 | This option creates a test to stress the ring buffer and benchmark it. |
| 576 | It creates its own ring buffer such that it will not interfere with |
Steven Rostedt | 5092dbc | 2009-05-05 22:47:18 -0400 | [diff] [blame] | 577 | any other users of the ring buffer (such as ftrace). It then creates |
| 578 | a producer and consumer that will run for 10 seconds and sleep for |
| 579 | 10 seconds. Each interval it will print out the number of events |
| 580 | it recorded and give a rough estimate of how long each iteration took. |
| 581 | |
| 582 | It does not disable interrupts or raise its priority, so it may be |
| 583 | affected by processes that are running. |
| 584 | |
Randy Dunlap | 4089236 | 2009-12-21 12:01:17 -0800 | [diff] [blame] | 585 | If unsure, say N. |
Steven Rostedt | 5092dbc | 2009-05-05 22:47:18 -0400 | [diff] [blame] | 586 | |
Steven Rostedt (Red Hat) | 6c43e55 | 2013-03-15 11:32:53 -0400 | [diff] [blame] | 587 | config RING_BUFFER_STARTUP_TEST |
| 588 | bool "Ring buffer startup self test" |
| 589 | depends on RING_BUFFER |
| 590 | help |
| 591 | Run a simple self test on the ring buffer on boot up. Late in the |
| 592 | kernel boot sequence, the test will start that kicks off |
| 593 | a thread per cpu. Each thread will write various size events |
| 594 | into the ring buffer. Another thread is created to send IPIs |
| 595 | to each of the threads, where the IPI handler will also write |
| 596 | to the ring buffer, to test/stress the nesting ability. |
| 597 | If any anomalies are discovered, a warning will be displayed |
| 598 | and all ring buffers will be disabled. |
| 599 | |
| 600 | The test runs for 10 seconds. This will slow your boot time |
| 601 | by at least 10 more seconds. |
| 602 | |
| 603 | At the end of the test, statics and more checks are done. |
| 604 | It will output the stats of each per cpu buffer. What |
| 605 | was written, the sizes, what was read, what was lost, and |
| 606 | other similar details. |
| 607 | |
| 608 | If unsure, say N |
| 609 | |
Steven Rostedt (Red Hat) | 9828413 | 2015-03-31 17:23:45 -0400 | [diff] [blame] | 610 | config TRACE_ENUM_MAP_FILE |
| 611 | bool "Show enum mappings for trace events" |
| 612 | depends on TRACING |
| 613 | help |
| 614 | The "print fmt" of the trace events will show the enum names instead |
| 615 | of their values. This can cause problems for user space tools that |
| 616 | use this string to parse the raw data as user space does not know |
| 617 | how to convert the string to its value. |
| 618 | |
| 619 | To fix this, there's a special macro in the kernel that can be used |
| 620 | to convert the enum into its value. If this macro is used, then the |
| 621 | print fmt strings will have the enums converted to their values. |
| 622 | |
| 623 | If something does not get converted properly, this option can be |
| 624 | used to show what enums the kernel tried to convert. |
| 625 | |
| 626 | This option is for debugging the enum conversions. A file is created |
| 627 | in the tracing directory called "enum_map" that will show the enum |
| 628 | names matched with their values and what trace event system they |
| 629 | belong too. |
| 630 | |
| 631 | Normally, the mapping of the strings to values will be freed after |
| 632 | boot up or module load. With this option, they will not be freed, as |
| 633 | they are needed for the "enum_map" file. Enabling this option will |
| 634 | increase the memory footprint of the running kernel. |
| 635 | |
| 636 | If unsure, say N |
| 637 | |
Steven Rostedt | 4ed9f07 | 2009-04-20 10:47:36 -0400 | [diff] [blame] | 638 | endif # FTRACE |
Ingo Molnar | 40ada30 | 2009-03-05 21:19:55 +0100 | [diff] [blame] | 639 | |
| 640 | endif # TRACING_SUPPORT |
| 641 | |