Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Infrastructure for profiling code inserted by 'gcc -pg'. |
| 3 | * |
| 4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> |
| 5 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> |
| 6 | * |
| 7 | * Originally ported from the -rt patch by: |
| 8 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> |
| 9 | * |
| 10 | * Based on code in the latency_tracer, that is: |
| 11 | * |
| 12 | * Copyright (C) 2004-2006 Ingo Molnar |
| 13 | * Copyright (C) 2004 William Lee Irwin III |
| 14 | */ |
| 15 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 16 | #include <linux/stop_machine.h> |
| 17 | #include <linux/clocksource.h> |
| 18 | #include <linux/kallsyms.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 19 | #include <linux/seq_file.h> |
Frederic Weisbecker | 4a2b8dd | 2009-01-14 13:33:27 -0800 | [diff] [blame] | 20 | #include <linux/suspend.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 21 | #include <linux/debugfs.h> |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 22 | #include <linux/hardirq.h> |
Ingo Molnar | 2d8b820 | 2008-02-23 16:55:50 +0100 | [diff] [blame] | 23 | #include <linux/kthread.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 24 | #include <linux/uaccess.h> |
Abhishek Sagar | f22f9a8 | 2008-06-21 23:50:29 +0530 | [diff] [blame] | 25 | #include <linux/kprobes.h> |
Ingo Molnar | 2d8b820 | 2008-02-23 16:55:50 +0100 | [diff] [blame] | 26 | #include <linux/ftrace.h> |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 27 | #include <linux/sysctl.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 28 | #include <linux/ctype.h> |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 29 | #include <linux/list.h> |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 30 | |
Abhishek Sagar | 395a59d | 2008-06-21 23:47:27 +0530 | [diff] [blame] | 31 | #include <asm/ftrace.h> |
| 32 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 33 | #include "trace.h" |
| 34 | |
Steven Rostedt | 6912896e | 2008-10-23 09:33:03 -0400 | [diff] [blame] | 35 | #define FTRACE_WARN_ON(cond) \ |
| 36 | do { \ |
| 37 | if (WARN_ON(cond)) \ |
| 38 | ftrace_kill(); \ |
| 39 | } while (0) |
| 40 | |
| 41 | #define FTRACE_WARN_ON_ONCE(cond) \ |
| 42 | do { \ |
| 43 | if (WARN_ON_ONCE(cond)) \ |
| 44 | ftrace_kill(); \ |
| 45 | } while (0) |
| 46 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 47 | /* ftrace_enabled is a method to turn ftrace on or off */ |
| 48 | int ftrace_enabled __read_mostly; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 49 | static int last_ftrace_enabled; |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 50 | |
Steven Rostedt | 0ef8cde | 2008-12-03 15:36:58 -0500 | [diff] [blame] | 51 | /* set when tracing only a pid */ |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 52 | struct pid *ftrace_pid_trace; |
Steven Rostedt | 21bbecd | 2008-12-04 23:30:56 -0500 | [diff] [blame] | 53 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 54 | |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 55 | /* Quick disabling of function tracer. */ |
| 56 | int function_trace_stop; |
| 57 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 58 | /* |
| 59 | * ftrace_disabled is set when an anomaly is discovered. |
| 60 | * ftrace_disabled is much stronger than ftrace_enabled. |
| 61 | */ |
| 62 | static int ftrace_disabled __read_mostly; |
| 63 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 64 | static DEFINE_SPINLOCK(ftrace_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 65 | static DEFINE_MUTEX(ftrace_sysctl_lock); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 66 | static DEFINE_MUTEX(ftrace_start_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 67 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 68 | static struct ftrace_ops ftrace_list_end __read_mostly = |
| 69 | { |
| 70 | .func = ftrace_stub, |
| 71 | }; |
| 72 | |
| 73 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; |
| 74 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 75 | ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 76 | ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 77 | |
Ingo Molnar | f225293 | 2008-05-22 10:37:48 +0200 | [diff] [blame] | 78 | static void ftrace_list_func(unsigned long ip, unsigned long parent_ip) |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 79 | { |
| 80 | struct ftrace_ops *op = ftrace_list; |
| 81 | |
| 82 | /* in case someone actually ports this to alpha! */ |
| 83 | read_barrier_depends(); |
| 84 | |
| 85 | while (op != &ftrace_list_end) { |
| 86 | /* silly alpha */ |
| 87 | read_barrier_depends(); |
| 88 | op->func(ip, parent_ip); |
| 89 | op = op->next; |
| 90 | }; |
| 91 | } |
| 92 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 93 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip) |
| 94 | { |
Steven Rostedt | 0ef8cde | 2008-12-03 15:36:58 -0500 | [diff] [blame] | 95 | if (!test_tsk_trace_trace(current)) |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 96 | return; |
| 97 | |
| 98 | ftrace_pid_function(ip, parent_ip); |
| 99 | } |
| 100 | |
| 101 | static void set_ftrace_pid_function(ftrace_func_t func) |
| 102 | { |
| 103 | /* do not set ftrace_pid_function to itself! */ |
| 104 | if (func != ftrace_pid_func) |
| 105 | ftrace_pid_function = func; |
| 106 | } |
| 107 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 108 | /** |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 109 | * clear_ftrace_function - reset the ftrace function |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 110 | * |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 111 | * This NULLs the ftrace function and in essence stops |
| 112 | * tracing. There may be lag |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 113 | */ |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 114 | void clear_ftrace_function(void) |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 115 | { |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 116 | ftrace_trace_function = ftrace_stub; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 117 | __ftrace_trace_function = ftrace_stub; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 118 | ftrace_pid_function = ftrace_stub; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 119 | } |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 120 | |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 121 | #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
| 122 | /* |
| 123 | * For those archs that do not test ftrace_trace_stop in their |
| 124 | * mcount call site, we need to do it from C. |
| 125 | */ |
| 126 | static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) |
| 127 | { |
| 128 | if (function_trace_stop) |
| 129 | return; |
| 130 | |
| 131 | __ftrace_trace_function(ip, parent_ip); |
| 132 | } |
| 133 | #endif |
| 134 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 135 | static int __register_ftrace_function(struct ftrace_ops *ops) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 136 | { |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 137 | /* should not be called from interrupt context */ |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 138 | spin_lock(&ftrace_lock); |
| 139 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 140 | ops->next = ftrace_list; |
| 141 | /* |
| 142 | * We are entering ops into the ftrace_list but another |
| 143 | * CPU might be walking that list. We need to make sure |
| 144 | * the ops->next pointer is valid before another CPU sees |
| 145 | * the ops pointer included into the ftrace_list. |
| 146 | */ |
| 147 | smp_wmb(); |
| 148 | ftrace_list = ops; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 149 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 150 | if (ftrace_enabled) { |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 151 | ftrace_func_t func; |
| 152 | |
| 153 | if (ops->next == &ftrace_list_end) |
| 154 | func = ops->func; |
| 155 | else |
| 156 | func = ftrace_list_func; |
| 157 | |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 158 | if (ftrace_pid_trace) { |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 159 | set_ftrace_pid_function(func); |
| 160 | func = ftrace_pid_func; |
| 161 | } |
| 162 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 163 | /* |
| 164 | * For one func, simply call it directly. |
| 165 | * For more than one func, call the chain. |
| 166 | */ |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 167 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 168 | ftrace_trace_function = func; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 169 | #else |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 170 | __ftrace_trace_function = func; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 171 | ftrace_trace_function = ftrace_test_stop_func; |
| 172 | #endif |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 173 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 174 | |
| 175 | spin_unlock(&ftrace_lock); |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 176 | |
| 177 | return 0; |
| 178 | } |
| 179 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 180 | static int __unregister_ftrace_function(struct ftrace_ops *ops) |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 181 | { |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 182 | struct ftrace_ops **p; |
| 183 | int ret = 0; |
| 184 | |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 185 | /* should not be called from interrupt context */ |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 186 | spin_lock(&ftrace_lock); |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 187 | |
| 188 | /* |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 189 | * If we are removing the last function, then simply point |
| 190 | * to the ftrace_stub. |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 191 | */ |
| 192 | if (ftrace_list == ops && ops->next == &ftrace_list_end) { |
| 193 | ftrace_trace_function = ftrace_stub; |
| 194 | ftrace_list = &ftrace_list_end; |
| 195 | goto out; |
| 196 | } |
| 197 | |
| 198 | for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) |
| 199 | if (*p == ops) |
| 200 | break; |
| 201 | |
| 202 | if (*p != ops) { |
| 203 | ret = -1; |
| 204 | goto out; |
| 205 | } |
| 206 | |
| 207 | *p = (*p)->next; |
| 208 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 209 | if (ftrace_enabled) { |
| 210 | /* If we only have one func left, then call that directly */ |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 211 | if (ftrace_list->next == &ftrace_list_end) { |
| 212 | ftrace_func_t func = ftrace_list->func; |
| 213 | |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 214 | if (ftrace_pid_trace) { |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 215 | set_ftrace_pid_function(func); |
| 216 | func = ftrace_pid_func; |
| 217 | } |
| 218 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
| 219 | ftrace_trace_function = func; |
| 220 | #else |
| 221 | __ftrace_trace_function = func; |
| 222 | #endif |
| 223 | } |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 224 | } |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 225 | |
| 226 | out: |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 227 | spin_unlock(&ftrace_lock); |
| 228 | |
| 229 | return ret; |
| 230 | } |
| 231 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 232 | static void ftrace_update_pid_func(void) |
| 233 | { |
| 234 | ftrace_func_t func; |
| 235 | |
| 236 | /* should not be called from interrupt context */ |
| 237 | spin_lock(&ftrace_lock); |
| 238 | |
| 239 | if (ftrace_trace_function == ftrace_stub) |
| 240 | goto out; |
| 241 | |
| 242 | func = ftrace_trace_function; |
| 243 | |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 244 | if (ftrace_pid_trace) { |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 245 | set_ftrace_pid_function(func); |
| 246 | func = ftrace_pid_func; |
| 247 | } else { |
Liming Wang | 66eafeb | 2008-12-02 10:33:08 +0800 | [diff] [blame] | 248 | if (func == ftrace_pid_func) |
| 249 | func = ftrace_pid_function; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 250 | } |
| 251 | |
| 252 | #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST |
| 253 | ftrace_trace_function = func; |
| 254 | #else |
| 255 | __ftrace_trace_function = func; |
| 256 | #endif |
| 257 | |
| 258 | out: |
| 259 | spin_unlock(&ftrace_lock); |
| 260 | } |
| 261 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 262 | #ifdef CONFIG_DYNAMIC_FTRACE |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 263 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 264 | # error Dynamic ftrace depends on MCOUNT_RECORD |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 265 | #endif |
| 266 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 267 | enum { |
| 268 | FTRACE_ENABLE_CALLS = (1 << 0), |
| 269 | FTRACE_DISABLE_CALLS = (1 << 1), |
| 270 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), |
| 271 | FTRACE_ENABLE_MCOUNT = (1 << 3), |
| 272 | FTRACE_DISABLE_MCOUNT = (1 << 4), |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 273 | FTRACE_START_FUNC_RET = (1 << 5), |
| 274 | FTRACE_STOP_FUNC_RET = (1 << 6), |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 275 | }; |
| 276 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 277 | static int ftrace_filtered; |
| 278 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 279 | static LIST_HEAD(ftrace_new_addrs); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 280 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 281 | static DEFINE_MUTEX(ftrace_regex_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 282 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 283 | struct ftrace_page { |
| 284 | struct ftrace_page *next; |
Steven Rostedt | 431aa3f | 2009-01-06 12:43:01 -0500 | [diff] [blame] | 285 | int index; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 286 | struct dyn_ftrace records[]; |
David Miller | aa5e5ce | 2008-05-13 22:06:56 -0700 | [diff] [blame] | 287 | }; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 288 | |
| 289 | #define ENTRIES_PER_PAGE \ |
| 290 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) |
| 291 | |
| 292 | /* estimate from running different kernels */ |
| 293 | #define NR_TO_INIT 10000 |
| 294 | |
| 295 | static struct ftrace_page *ftrace_pages_start; |
| 296 | static struct ftrace_page *ftrace_pages; |
| 297 | |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 298 | static struct dyn_ftrace *ftrace_free_records; |
| 299 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 300 | /* |
| 301 | * This is a double for. Do not use 'break' to break out of the loop, |
| 302 | * you must use a goto. |
| 303 | */ |
| 304 | #define do_for_each_ftrace_rec(pg, rec) \ |
| 305 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ |
| 306 | int _____i; \ |
| 307 | for (_____i = 0; _____i < pg->index; _____i++) { \ |
| 308 | rec = &pg->records[_____i]; |
| 309 | |
| 310 | #define while_for_each_ftrace_rec() \ |
| 311 | } \ |
| 312 | } |
Abhishek Sagar | ecea656 | 2008-06-21 23:47:53 +0530 | [diff] [blame] | 313 | |
| 314 | #ifdef CONFIG_KPROBES |
Ingo Molnar | f17845e | 2008-10-24 12:47:10 +0200 | [diff] [blame] | 315 | |
| 316 | static int frozen_record_count; |
| 317 | |
Abhishek Sagar | ecea656 | 2008-06-21 23:47:53 +0530 | [diff] [blame] | 318 | static inline void freeze_record(struct dyn_ftrace *rec) |
| 319 | { |
| 320 | if (!(rec->flags & FTRACE_FL_FROZEN)) { |
| 321 | rec->flags |= FTRACE_FL_FROZEN; |
| 322 | frozen_record_count++; |
| 323 | } |
| 324 | } |
| 325 | |
| 326 | static inline void unfreeze_record(struct dyn_ftrace *rec) |
| 327 | { |
| 328 | if (rec->flags & FTRACE_FL_FROZEN) { |
| 329 | rec->flags &= ~FTRACE_FL_FROZEN; |
| 330 | frozen_record_count--; |
| 331 | } |
| 332 | } |
| 333 | |
| 334 | static inline int record_frozen(struct dyn_ftrace *rec) |
| 335 | { |
| 336 | return rec->flags & FTRACE_FL_FROZEN; |
| 337 | } |
| 338 | #else |
| 339 | # define freeze_record(rec) ({ 0; }) |
| 340 | # define unfreeze_record(rec) ({ 0; }) |
| 341 | # define record_frozen(rec) ({ 0; }) |
| 342 | #endif /* CONFIG_KPROBES */ |
| 343 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 344 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 345 | { |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 346 | rec->ip = (unsigned long)ftrace_free_records; |
| 347 | ftrace_free_records = rec; |
| 348 | rec->flags |= FTRACE_FL_FREE; |
| 349 | } |
| 350 | |
Steven Rostedt | fed1939 | 2008-08-14 22:47:19 -0400 | [diff] [blame] | 351 | void ftrace_release(void *start, unsigned long size) |
| 352 | { |
| 353 | struct dyn_ftrace *rec; |
| 354 | struct ftrace_page *pg; |
| 355 | unsigned long s = (unsigned long)start; |
| 356 | unsigned long e = s + size; |
Steven Rostedt | fed1939 | 2008-08-14 22:47:19 -0400 | [diff] [blame] | 357 | |
Steven Rostedt | 00fd61a | 2008-08-15 21:40:04 -0400 | [diff] [blame] | 358 | if (ftrace_disabled || !start) |
Steven Rostedt | fed1939 | 2008-08-14 22:47:19 -0400 | [diff] [blame] | 359 | return; |
| 360 | |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 361 | /* should not be called from interrupt context */ |
Steven Rostedt | fed1939 | 2008-08-14 22:47:19 -0400 | [diff] [blame] | 362 | spin_lock(&ftrace_lock); |
| 363 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 364 | do_for_each_ftrace_rec(pg, rec) { |
| 365 | if ((rec->ip >= s) && (rec->ip < e)) |
| 366 | ftrace_free_rec(rec); |
| 367 | } while_for_each_ftrace_rec(); |
Steven Rostedt | fed1939 | 2008-08-14 22:47:19 -0400 | [diff] [blame] | 368 | |
Steven Rostedt | fed1939 | 2008-08-14 22:47:19 -0400 | [diff] [blame] | 369 | spin_unlock(&ftrace_lock); |
Steven Rostedt | fed1939 | 2008-08-14 22:47:19 -0400 | [diff] [blame] | 370 | } |
| 371 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 372 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 373 | { |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 374 | struct dyn_ftrace *rec; |
| 375 | |
| 376 | /* First check for freed records */ |
| 377 | if (ftrace_free_records) { |
| 378 | rec = ftrace_free_records; |
| 379 | |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 380 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
Steven Rostedt | 6912896e | 2008-10-23 09:33:03 -0400 | [diff] [blame] | 381 | FTRACE_WARN_ON_ONCE(1); |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 382 | ftrace_free_records = NULL; |
| 383 | return NULL; |
| 384 | } |
| 385 | |
| 386 | ftrace_free_records = (void *)rec->ip; |
| 387 | memset(rec, 0, sizeof(*rec)); |
| 388 | return rec; |
| 389 | } |
| 390 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 391 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 392 | if (!ftrace_pages->next) { |
| 393 | /* allocate another page */ |
| 394 | ftrace_pages->next = |
| 395 | (void *)get_zeroed_page(GFP_KERNEL); |
| 396 | if (!ftrace_pages->next) |
| 397 | return NULL; |
| 398 | } |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 399 | ftrace_pages = ftrace_pages->next; |
| 400 | } |
| 401 | |
| 402 | return &ftrace_pages->records[ftrace_pages->index++]; |
| 403 | } |
| 404 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 405 | static struct dyn_ftrace * |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 406 | ftrace_record_ip(unsigned long ip) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 407 | { |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 408 | struct dyn_ftrace *rec; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 409 | |
Steven Rostedt | f3c7ac4 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 410 | if (ftrace_disabled) |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 411 | return NULL; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 412 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 413 | rec = ftrace_alloc_dyn_node(ip); |
| 414 | if (!rec) |
| 415 | return NULL; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 416 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 417 | rec->ip = ip; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 418 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 419 | list_add(&rec->list, &ftrace_new_addrs); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 420 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 421 | return rec; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 422 | } |
| 423 | |
Steven Rostedt | 05736a4 | 2008-09-22 14:55:47 -0700 | [diff] [blame] | 424 | static void print_ip_ins(const char *fmt, unsigned char *p) |
| 425 | { |
| 426 | int i; |
| 427 | |
| 428 | printk(KERN_CONT "%s", fmt); |
| 429 | |
| 430 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) |
| 431 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); |
| 432 | } |
| 433 | |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 434 | static void ftrace_bug(int failed, unsigned long ip) |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 435 | { |
| 436 | switch (failed) { |
| 437 | case -EFAULT: |
| 438 | FTRACE_WARN_ON_ONCE(1); |
| 439 | pr_info("ftrace faulted on modifying "); |
| 440 | print_ip_sym(ip); |
| 441 | break; |
| 442 | case -EINVAL: |
| 443 | FTRACE_WARN_ON_ONCE(1); |
| 444 | pr_info("ftrace failed to modify "); |
| 445 | print_ip_sym(ip); |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 446 | print_ip_ins(" actual: ", (unsigned char *)ip); |
Steven Rostedt | b17e8a3 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 447 | printk(KERN_CONT "\n"); |
| 448 | break; |
| 449 | case -EPERM: |
| 450 | FTRACE_WARN_ON_ONCE(1); |
| 451 | pr_info("ftrace faulted on writing "); |
| 452 | print_ip_sym(ip); |
| 453 | break; |
| 454 | default: |
| 455 | FTRACE_WARN_ON_ONCE(1); |
| 456 | pr_info("ftrace faulted on unknown error "); |
| 457 | print_ip_sym(ip); |
| 458 | } |
| 459 | } |
| 460 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 461 | |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 462 | static int |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 463 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 464 | { |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 465 | unsigned long ip, fl; |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 466 | unsigned long ftrace_addr; |
| 467 | |
Shaohua Li | f000120 | 2009-01-09 11:29:42 +0800 | [diff] [blame] | 468 | ftrace_addr = (unsigned long)FTRACE_ADDR; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 469 | |
| 470 | ip = rec->ip; |
| 471 | |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 472 | /* |
| 473 | * If this record is not to be traced and |
| 474 | * it is not enabled then do nothing. |
| 475 | * |
| 476 | * If this record is not to be traced and |
Wenji Huang | 57794a9 | 2009-02-06 17:33:27 +0800 | [diff] [blame] | 477 | * it is enabled then disable it. |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 478 | * |
| 479 | */ |
| 480 | if (rec->flags & FTRACE_FL_NOTRACE) { |
| 481 | if (rec->flags & FTRACE_FL_ENABLED) |
| 482 | rec->flags &= ~FTRACE_FL_ENABLED; |
| 483 | else |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 484 | return 0; |
| 485 | |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 486 | } else if (ftrace_filtered && enable) { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 487 | /* |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 488 | * Filtering is on: |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 489 | */ |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 490 | |
| 491 | fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED); |
| 492 | |
| 493 | /* Record is filtered and enabled, do nothing */ |
| 494 | if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) |
| 495 | return 0; |
| 496 | |
Wenji Huang | 57794a9 | 2009-02-06 17:33:27 +0800 | [diff] [blame] | 497 | /* Record is not filtered or enabled, do nothing */ |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 498 | if (!fl) |
| 499 | return 0; |
| 500 | |
| 501 | /* Record is not filtered but enabled, disable it */ |
| 502 | if (fl == FTRACE_FL_ENABLED) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 503 | rec->flags &= ~FTRACE_FL_ENABLED; |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 504 | else |
| 505 | /* Otherwise record is filtered but not enabled, enable it */ |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 506 | rec->flags |= FTRACE_FL_ENABLED; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 507 | } else { |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 508 | /* Disable or not filtered */ |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 509 | |
| 510 | if (enable) { |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 511 | /* if record is enabled, do nothing */ |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 512 | if (rec->flags & FTRACE_FL_ENABLED) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 513 | return 0; |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 514 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 515 | rec->flags |= FTRACE_FL_ENABLED; |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 516 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 517 | } else { |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 518 | |
Wenji Huang | 57794a9 | 2009-02-06 17:33:27 +0800 | [diff] [blame] | 519 | /* if record is not enabled, do nothing */ |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 520 | if (!(rec->flags & FTRACE_FL_ENABLED)) |
| 521 | return 0; |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 522 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 523 | rec->flags &= ~FTRACE_FL_ENABLED; |
| 524 | } |
| 525 | } |
| 526 | |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 527 | if (rec->flags & FTRACE_FL_ENABLED) |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 528 | return ftrace_make_call(rec, ftrace_addr); |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 529 | else |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 530 | return ftrace_make_nop(NULL, rec, ftrace_addr); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 531 | } |
| 532 | |
| 533 | static void ftrace_replace_code(int enable) |
| 534 | { |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 535 | int failed; |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 536 | struct dyn_ftrace *rec; |
| 537 | struct ftrace_page *pg; |
| 538 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 539 | do_for_each_ftrace_rec(pg, rec) { |
| 540 | /* |
| 541 | * Skip over free records and records that have |
| 542 | * failed. |
| 543 | */ |
| 544 | if (rec->flags & FTRACE_FL_FREE || |
| 545 | rec->flags & FTRACE_FL_FAILED) |
| 546 | continue; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 547 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 548 | /* ignore updates to this record's mcount site */ |
| 549 | if (get_kprobe((void *)rec->ip)) { |
| 550 | freeze_record(rec); |
| 551 | continue; |
| 552 | } else { |
| 553 | unfreeze_record(rec); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 554 | } |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 555 | |
| 556 | failed = __ftrace_replace_code(rec, enable); |
| 557 | if (failed && (rec->flags & FTRACE_FL_CONVERTED)) { |
| 558 | rec->flags |= FTRACE_FL_FAILED; |
| 559 | if ((system_state == SYSTEM_BOOTING) || |
| 560 | !core_kernel_text(rec->ip)) { |
| 561 | ftrace_free_rec(rec); |
| 562 | } else |
| 563 | ftrace_bug(failed, rec->ip); |
| 564 | } |
| 565 | } while_for_each_ftrace_rec(); |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 566 | } |
| 567 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 568 | static int |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 569 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 570 | { |
| 571 | unsigned long ip; |
Steven Rostedt | 593eb8a | 2008-10-23 09:32:59 -0400 | [diff] [blame] | 572 | int ret; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 573 | |
| 574 | ip = rec->ip; |
| 575 | |
Shaohua Li | 25aac9d | 2009-01-09 11:29:40 +0800 | [diff] [blame] | 576 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
Steven Rostedt | 593eb8a | 2008-10-23 09:32:59 -0400 | [diff] [blame] | 577 | if (ret) { |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 578 | ftrace_bug(ret, ip); |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 579 | rec->flags |= FTRACE_FL_FAILED; |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 580 | return 0; |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 581 | } |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 582 | return 1; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 583 | } |
| 584 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 585 | static int __ftrace_modify_code(void *data) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 586 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 587 | int *command = data; |
| 588 | |
Steven Rostedt | a358324 | 2008-11-11 15:01:42 -0500 | [diff] [blame] | 589 | if (*command & FTRACE_ENABLE_CALLS) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 590 | ftrace_replace_code(1); |
Steven Rostedt | a358324 | 2008-11-11 15:01:42 -0500 | [diff] [blame] | 591 | else if (*command & FTRACE_DISABLE_CALLS) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 592 | ftrace_replace_code(0); |
| 593 | |
| 594 | if (*command & FTRACE_UPDATE_TRACE_FUNC) |
| 595 | ftrace_update_ftrace_func(ftrace_trace_function); |
| 596 | |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 597 | if (*command & FTRACE_START_FUNC_RET) |
| 598 | ftrace_enable_ftrace_graph_caller(); |
| 599 | else if (*command & FTRACE_STOP_FUNC_RET) |
| 600 | ftrace_disable_ftrace_graph_caller(); |
| 601 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 602 | return 0; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 603 | } |
| 604 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 605 | static void ftrace_run_update_code(int command) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 606 | { |
Rusty Russell | 784e2d7 | 2008-07-28 12:16:31 -0500 | [diff] [blame] | 607 | stop_machine(__ftrace_modify_code, &command, NULL); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 608 | } |
| 609 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 610 | static ftrace_func_t saved_ftrace_func; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 611 | static int ftrace_start_up; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 612 | |
| 613 | static void ftrace_startup_enable(int command) |
| 614 | { |
| 615 | if (saved_ftrace_func != ftrace_trace_function) { |
| 616 | saved_ftrace_func = ftrace_trace_function; |
| 617 | command |= FTRACE_UPDATE_TRACE_FUNC; |
| 618 | } |
| 619 | |
| 620 | if (!command || !ftrace_enabled) |
| 621 | return; |
| 622 | |
| 623 | ftrace_run_update_code(command); |
| 624 | } |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 625 | |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 626 | static void ftrace_startup(int command) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 627 | { |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 628 | if (unlikely(ftrace_disabled)) |
| 629 | return; |
| 630 | |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 631 | mutex_lock(&ftrace_start_lock); |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 632 | ftrace_start_up++; |
Steven Rostedt | 982c350 | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 633 | command |= FTRACE_ENABLE_CALLS; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 634 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 635 | ftrace_startup_enable(command); |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 636 | |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 637 | mutex_unlock(&ftrace_start_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 638 | } |
| 639 | |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 640 | static void ftrace_shutdown(int command) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 641 | { |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 642 | if (unlikely(ftrace_disabled)) |
| 643 | return; |
| 644 | |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 645 | mutex_lock(&ftrace_start_lock); |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 646 | ftrace_start_up--; |
| 647 | if (!ftrace_start_up) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 648 | command |= FTRACE_DISABLE_CALLS; |
| 649 | |
| 650 | if (saved_ftrace_func != ftrace_trace_function) { |
| 651 | saved_ftrace_func = ftrace_trace_function; |
| 652 | command |= FTRACE_UPDATE_TRACE_FUNC; |
| 653 | } |
| 654 | |
| 655 | if (!command || !ftrace_enabled) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 656 | goto out; |
| 657 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 658 | ftrace_run_update_code(command); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 659 | out: |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 660 | mutex_unlock(&ftrace_start_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 661 | } |
| 662 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 663 | static void ftrace_startup_sysctl(void) |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 664 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 665 | int command = FTRACE_ENABLE_MCOUNT; |
| 666 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 667 | if (unlikely(ftrace_disabled)) |
| 668 | return; |
| 669 | |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 670 | mutex_lock(&ftrace_start_lock); |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 671 | /* Force update next time */ |
| 672 | saved_ftrace_func = NULL; |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 673 | /* ftrace_start_up is true if we want ftrace running */ |
| 674 | if (ftrace_start_up) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 675 | command |= FTRACE_ENABLE_CALLS; |
| 676 | |
| 677 | ftrace_run_update_code(command); |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 678 | mutex_unlock(&ftrace_start_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 679 | } |
| 680 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 681 | static void ftrace_shutdown_sysctl(void) |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 682 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 683 | int command = FTRACE_DISABLE_MCOUNT; |
| 684 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 685 | if (unlikely(ftrace_disabled)) |
| 686 | return; |
| 687 | |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 688 | mutex_lock(&ftrace_start_lock); |
Steven Rostedt | 60a7ecf | 2008-11-05 16:05:44 -0500 | [diff] [blame] | 689 | /* ftrace_start_up is true if ftrace is running */ |
| 690 | if (ftrace_start_up) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 691 | command |= FTRACE_DISABLE_CALLS; |
| 692 | |
| 693 | ftrace_run_update_code(command); |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 694 | mutex_unlock(&ftrace_start_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 695 | } |
| 696 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 697 | static cycle_t ftrace_update_time; |
| 698 | static unsigned long ftrace_update_cnt; |
| 699 | unsigned long ftrace_update_tot_cnt; |
| 700 | |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 701 | static int ftrace_update_code(struct module *mod) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 702 | { |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 703 | struct dyn_ftrace *p, *t; |
Abhishek Sagar | f22f9a8 | 2008-06-21 23:50:29 +0530 | [diff] [blame] | 704 | cycle_t start, stop; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 705 | |
Ingo Molnar | 750ed1a | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 706 | start = ftrace_now(raw_smp_processor_id()); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 707 | ftrace_update_cnt = 0; |
| 708 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 709 | list_for_each_entry_safe(p, t, &ftrace_new_addrs, list) { |
Abhishek Sagar | f22f9a8 | 2008-06-21 23:50:29 +0530 | [diff] [blame] | 710 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 711 | /* If something went wrong, bail without enabling anything */ |
| 712 | if (unlikely(ftrace_disabled)) |
| 713 | return -1; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 714 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 715 | list_del_init(&p->list); |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame] | 716 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 717 | /* convert record (i.e, patch mcount-call with NOP) */ |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 718 | if (ftrace_code_disable(mod, p)) { |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 719 | p->flags |= FTRACE_FL_CONVERTED; |
| 720 | ftrace_update_cnt++; |
| 721 | } else |
| 722 | ftrace_free_rec(p); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 723 | } |
| 724 | |
Ingo Molnar | 750ed1a | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 725 | stop = ftrace_now(raw_smp_processor_id()); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 726 | ftrace_update_time = stop - start; |
| 727 | ftrace_update_tot_cnt += ftrace_update_cnt; |
| 728 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 729 | return 0; |
| 730 | } |
| 731 | |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 732 | static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 733 | { |
| 734 | struct ftrace_page *pg; |
| 735 | int cnt; |
| 736 | int i; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 737 | |
| 738 | /* allocate a few pages */ |
| 739 | ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL); |
| 740 | if (!ftrace_pages_start) |
| 741 | return -1; |
| 742 | |
| 743 | /* |
| 744 | * Allocate a few more pages. |
| 745 | * |
| 746 | * TODO: have some parser search vmlinux before |
| 747 | * final linking to find all calls to ftrace. |
| 748 | * Then we can: |
| 749 | * a) know how many pages to allocate. |
| 750 | * and/or |
| 751 | * b) set up the table then. |
| 752 | * |
| 753 | * The dynamic code is still necessary for |
| 754 | * modules. |
| 755 | */ |
| 756 | |
| 757 | pg = ftrace_pages = ftrace_pages_start; |
| 758 | |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 759 | cnt = num_to_init / ENTRIES_PER_PAGE; |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 760 | pr_info("ftrace: allocating %ld entries in %d pages\n", |
walimis | 5821e1b | 2008-11-15 15:19:06 +0800 | [diff] [blame] | 761 | num_to_init, cnt + 1); |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 762 | |
| 763 | for (i = 0; i < cnt; i++) { |
| 764 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
| 765 | |
| 766 | /* If we fail, we'll try later anyway */ |
| 767 | if (!pg->next) |
| 768 | break; |
| 769 | |
| 770 | pg = pg->next; |
| 771 | } |
| 772 | |
| 773 | return 0; |
| 774 | } |
| 775 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 776 | enum { |
| 777 | FTRACE_ITER_FILTER = (1 << 0), |
| 778 | FTRACE_ITER_CONT = (1 << 1), |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 779 | FTRACE_ITER_NOTRACE = (1 << 2), |
Abhishek Sagar | eb9a7bf | 2008-06-01 21:47:54 +0530 | [diff] [blame] | 780 | FTRACE_ITER_FAILURES = (1 << 3), |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 781 | FTRACE_ITER_PRINTALL = (1 << 4), |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 782 | }; |
| 783 | |
| 784 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
| 785 | |
| 786 | struct ftrace_iterator { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 787 | struct ftrace_page *pg; |
Steven Rostedt | 431aa3f | 2009-01-06 12:43:01 -0500 | [diff] [blame] | 788 | int idx; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 789 | unsigned flags; |
| 790 | unsigned char buffer[FTRACE_BUFF_MAX+1]; |
| 791 | unsigned buffer_idx; |
| 792 | unsigned filtered; |
| 793 | }; |
| 794 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 795 | static void * |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 796 | t_next(struct seq_file *m, void *v, loff_t *pos) |
| 797 | { |
| 798 | struct ftrace_iterator *iter = m->private; |
| 799 | struct dyn_ftrace *rec = NULL; |
| 800 | |
| 801 | (*pos)++; |
| 802 | |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 803 | if (iter->flags & FTRACE_ITER_PRINTALL) |
| 804 | return NULL; |
| 805 | |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 806 | /* should not be called from interrupt context */ |
| 807 | spin_lock(&ftrace_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 808 | retry: |
| 809 | if (iter->idx >= iter->pg->index) { |
| 810 | if (iter->pg->next) { |
| 811 | iter->pg = iter->pg->next; |
| 812 | iter->idx = 0; |
| 813 | goto retry; |
Liming Wang | 50cdaf0 | 2008-11-28 12:13:21 +0800 | [diff] [blame] | 814 | } else { |
| 815 | iter->idx = -1; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 816 | } |
| 817 | } else { |
| 818 | rec = &iter->pg->records[iter->idx++]; |
Steven Rostedt | a9fdda3 | 2008-08-14 22:47:17 -0400 | [diff] [blame] | 819 | if ((rec->flags & FTRACE_FL_FREE) || |
| 820 | |
| 821 | (!(iter->flags & FTRACE_ITER_FAILURES) && |
Abhishek Sagar | eb9a7bf | 2008-06-01 21:47:54 +0530 | [diff] [blame] | 822 | (rec->flags & FTRACE_FL_FAILED)) || |
| 823 | |
| 824 | ((iter->flags & FTRACE_ITER_FAILURES) && |
Steven Rostedt | a9fdda3 | 2008-08-14 22:47:17 -0400 | [diff] [blame] | 825 | !(rec->flags & FTRACE_FL_FAILED)) || |
Abhishek Sagar | eb9a7bf | 2008-06-01 21:47:54 +0530 | [diff] [blame] | 826 | |
Steven Rostedt | 0183fb1 | 2008-11-07 22:36:02 -0500 | [diff] [blame] | 827 | ((iter->flags & FTRACE_ITER_FILTER) && |
| 828 | !(rec->flags & FTRACE_FL_FILTER)) || |
| 829 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 830 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
| 831 | !(rec->flags & FTRACE_FL_NOTRACE))) { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 832 | rec = NULL; |
| 833 | goto retry; |
| 834 | } |
| 835 | } |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 836 | spin_unlock(&ftrace_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 837 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 838 | return rec; |
| 839 | } |
| 840 | |
| 841 | static void *t_start(struct seq_file *m, loff_t *pos) |
| 842 | { |
| 843 | struct ftrace_iterator *iter = m->private; |
| 844 | void *p = NULL; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 845 | |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 846 | /* |
| 847 | * For set_ftrace_filter reading, if we have the filter |
| 848 | * off, we can short cut and just print out that all |
| 849 | * functions are enabled. |
| 850 | */ |
| 851 | if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) { |
| 852 | if (*pos > 0) |
| 853 | return NULL; |
| 854 | iter->flags |= FTRACE_ITER_PRINTALL; |
| 855 | (*pos)++; |
| 856 | return iter; |
| 857 | } |
| 858 | |
Liming Wang | 50cdaf0 | 2008-11-28 12:13:21 +0800 | [diff] [blame] | 859 | if (*pos > 0) { |
| 860 | if (iter->idx < 0) |
| 861 | return p; |
| 862 | (*pos)--; |
| 863 | iter->idx--; |
| 864 | } |
walimis | 5821e1b | 2008-11-15 15:19:06 +0800 | [diff] [blame] | 865 | |
Liming Wang | 50cdaf0 | 2008-11-28 12:13:21 +0800 | [diff] [blame] | 866 | p = t_next(m, p, pos); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 867 | |
| 868 | return p; |
| 869 | } |
| 870 | |
| 871 | static void t_stop(struct seq_file *m, void *p) |
| 872 | { |
| 873 | } |
| 874 | |
| 875 | static int t_show(struct seq_file *m, void *v) |
| 876 | { |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 877 | struct ftrace_iterator *iter = m->private; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 878 | struct dyn_ftrace *rec = v; |
| 879 | char str[KSYM_SYMBOL_LEN]; |
| 880 | |
Steven Rostedt | 0c75a3e | 2009-02-16 11:21:52 -0500 | [diff] [blame] | 881 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
| 882 | seq_printf(m, "#### all functions enabled ####\n"); |
| 883 | return 0; |
| 884 | } |
| 885 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 886 | if (!rec) |
| 887 | return 0; |
| 888 | |
| 889 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
| 890 | |
Liming Wang | 50cdaf0 | 2008-11-28 12:13:21 +0800 | [diff] [blame] | 891 | seq_printf(m, "%s\n", str); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 892 | |
| 893 | return 0; |
| 894 | } |
| 895 | |
| 896 | static struct seq_operations show_ftrace_seq_ops = { |
| 897 | .start = t_start, |
| 898 | .next = t_next, |
| 899 | .stop = t_stop, |
| 900 | .show = t_show, |
| 901 | }; |
| 902 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 903 | static int |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 904 | ftrace_avail_open(struct inode *inode, struct file *file) |
| 905 | { |
| 906 | struct ftrace_iterator *iter; |
| 907 | int ret; |
| 908 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 909 | if (unlikely(ftrace_disabled)) |
| 910 | return -ENODEV; |
| 911 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 912 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
| 913 | if (!iter) |
| 914 | return -ENOMEM; |
| 915 | |
| 916 | iter->pg = ftrace_pages_start; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 917 | |
| 918 | ret = seq_open(file, &show_ftrace_seq_ops); |
| 919 | if (!ret) { |
| 920 | struct seq_file *m = file->private_data; |
Ingo Molnar | 4bf39a9 | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 921 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 922 | m->private = iter; |
Ingo Molnar | 4bf39a9 | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 923 | } else { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 924 | kfree(iter); |
Ingo Molnar | 4bf39a9 | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 925 | } |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 926 | |
| 927 | return ret; |
| 928 | } |
| 929 | |
| 930 | int ftrace_avail_release(struct inode *inode, struct file *file) |
| 931 | { |
| 932 | struct seq_file *m = (struct seq_file *)file->private_data; |
| 933 | struct ftrace_iterator *iter = m->private; |
| 934 | |
| 935 | seq_release(inode, file); |
| 936 | kfree(iter); |
Ingo Molnar | 4bf39a9 | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 937 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 938 | return 0; |
| 939 | } |
| 940 | |
Abhishek Sagar | eb9a7bf | 2008-06-01 21:47:54 +0530 | [diff] [blame] | 941 | static int |
| 942 | ftrace_failures_open(struct inode *inode, struct file *file) |
| 943 | { |
| 944 | int ret; |
| 945 | struct seq_file *m; |
| 946 | struct ftrace_iterator *iter; |
| 947 | |
| 948 | ret = ftrace_avail_open(inode, file); |
| 949 | if (!ret) { |
| 950 | m = (struct seq_file *)file->private_data; |
| 951 | iter = (struct ftrace_iterator *)m->private; |
| 952 | iter->flags = FTRACE_ITER_FAILURES; |
| 953 | } |
| 954 | |
| 955 | return ret; |
| 956 | } |
| 957 | |
| 958 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 959 | static void ftrace_filter_reset(int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 960 | { |
| 961 | struct ftrace_page *pg; |
| 962 | struct dyn_ftrace *rec; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 963 | unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 964 | |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 965 | /* should not be called from interrupt context */ |
| 966 | spin_lock(&ftrace_lock); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 967 | if (enable) |
| 968 | ftrace_filtered = 0; |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 969 | do_for_each_ftrace_rec(pg, rec) { |
| 970 | if (rec->flags & FTRACE_FL_FAILED) |
| 971 | continue; |
| 972 | rec->flags &= ~type; |
| 973 | } while_for_each_ftrace_rec(); |
| 974 | |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 975 | spin_unlock(&ftrace_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 976 | } |
| 977 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 978 | static int |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 979 | ftrace_regex_open(struct inode *inode, struct file *file, int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 980 | { |
| 981 | struct ftrace_iterator *iter; |
| 982 | int ret = 0; |
| 983 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 984 | if (unlikely(ftrace_disabled)) |
| 985 | return -ENODEV; |
| 986 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 987 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
| 988 | if (!iter) |
| 989 | return -ENOMEM; |
| 990 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 991 | mutex_lock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 992 | if ((file->f_mode & FMODE_WRITE) && |
| 993 | !(file->f_flags & O_APPEND)) |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 994 | ftrace_filter_reset(enable); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 995 | |
| 996 | if (file->f_mode & FMODE_READ) { |
| 997 | iter->pg = ftrace_pages_start; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 998 | iter->flags = enable ? FTRACE_ITER_FILTER : |
| 999 | FTRACE_ITER_NOTRACE; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1000 | |
| 1001 | ret = seq_open(file, &show_ftrace_seq_ops); |
| 1002 | if (!ret) { |
| 1003 | struct seq_file *m = file->private_data; |
| 1004 | m->private = iter; |
| 1005 | } else |
| 1006 | kfree(iter); |
| 1007 | } else |
| 1008 | file->private_data = iter; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1009 | mutex_unlock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1010 | |
| 1011 | return ret; |
| 1012 | } |
| 1013 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1014 | static int |
| 1015 | ftrace_filter_open(struct inode *inode, struct file *file) |
| 1016 | { |
| 1017 | return ftrace_regex_open(inode, file, 1); |
| 1018 | } |
| 1019 | |
| 1020 | static int |
| 1021 | ftrace_notrace_open(struct inode *inode, struct file *file) |
| 1022 | { |
| 1023 | return ftrace_regex_open(inode, file, 0); |
| 1024 | } |
| 1025 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1026 | static ssize_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1027 | ftrace_regex_read(struct file *file, char __user *ubuf, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1028 | size_t cnt, loff_t *ppos) |
| 1029 | { |
| 1030 | if (file->f_mode & FMODE_READ) |
| 1031 | return seq_read(file, ubuf, cnt, ppos); |
| 1032 | else |
| 1033 | return -EPERM; |
| 1034 | } |
| 1035 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1036 | static loff_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1037 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1038 | { |
| 1039 | loff_t ret; |
| 1040 | |
| 1041 | if (file->f_mode & FMODE_READ) |
| 1042 | ret = seq_lseek(file, offset, origin); |
| 1043 | else |
| 1044 | file->f_pos = ret = 1; |
| 1045 | |
| 1046 | return ret; |
| 1047 | } |
| 1048 | |
| 1049 | enum { |
| 1050 | MATCH_FULL, |
| 1051 | MATCH_FRONT_ONLY, |
| 1052 | MATCH_MIDDLE_ONLY, |
| 1053 | MATCH_END_ONLY, |
| 1054 | }; |
| 1055 | |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1056 | /* |
| 1057 | * (static function - no need for kernel doc) |
| 1058 | * |
| 1059 | * Pass in a buffer containing a glob and this function will |
| 1060 | * set search to point to the search part of the buffer and |
| 1061 | * return the type of search it is (see enum above). |
| 1062 | * This does modify buff. |
| 1063 | * |
| 1064 | * Returns enum type. |
| 1065 | * search returns the pointer to use for comparison. |
| 1066 | * not returns 1 if buff started with a '!' |
| 1067 | * 0 otherwise. |
| 1068 | */ |
| 1069 | static int |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1070 | ftrace_setup_glob(char *buff, int len, char **search, int *not) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1071 | { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1072 | int type = MATCH_FULL; |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1073 | int i; |
Steven Rostedt | ea3a6d6 | 2008-12-17 15:05:36 -0500 | [diff] [blame] | 1074 | |
| 1075 | if (buff[0] == '!') { |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1076 | *not = 1; |
Steven Rostedt | ea3a6d6 | 2008-12-17 15:05:36 -0500 | [diff] [blame] | 1077 | buff++; |
| 1078 | len--; |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1079 | } else |
| 1080 | *not = 0; |
| 1081 | |
| 1082 | *search = buff; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1083 | |
| 1084 | for (i = 0; i < len; i++) { |
| 1085 | if (buff[i] == '*') { |
| 1086 | if (!i) { |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1087 | *search = buff + 1; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1088 | type = MATCH_END_ONLY; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1089 | } else { |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1090 | if (type == MATCH_END_ONLY) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1091 | type = MATCH_MIDDLE_ONLY; |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1092 | else |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1093 | type = MATCH_FRONT_ONLY; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1094 | buff[i] = 0; |
| 1095 | break; |
| 1096 | } |
| 1097 | } |
| 1098 | } |
| 1099 | |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1100 | return type; |
| 1101 | } |
| 1102 | |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1103 | static int ftrace_match(char *str, char *regex, int len, int type) |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1104 | { |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1105 | int matched = 0; |
| 1106 | char *ptr; |
| 1107 | |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1108 | switch (type) { |
| 1109 | case MATCH_FULL: |
| 1110 | if (strcmp(str, regex) == 0) |
| 1111 | matched = 1; |
| 1112 | break; |
| 1113 | case MATCH_FRONT_ONLY: |
| 1114 | if (strncmp(str, regex, len) == 0) |
| 1115 | matched = 1; |
| 1116 | break; |
| 1117 | case MATCH_MIDDLE_ONLY: |
| 1118 | if (strstr(str, regex)) |
| 1119 | matched = 1; |
| 1120 | break; |
| 1121 | case MATCH_END_ONLY: |
| 1122 | ptr = strstr(str, regex); |
| 1123 | if (ptr && (ptr[len] == 0)) |
| 1124 | matched = 1; |
| 1125 | break; |
| 1126 | } |
| 1127 | |
| 1128 | return matched; |
| 1129 | } |
| 1130 | |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1131 | static int |
| 1132 | ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type) |
| 1133 | { |
| 1134 | char str[KSYM_SYMBOL_LEN]; |
| 1135 | |
| 1136 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
| 1137 | return ftrace_match(str, regex, len, type); |
| 1138 | } |
| 1139 | |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1140 | static void ftrace_match_records(char *buff, int len, int enable) |
| 1141 | { |
| 1142 | char *search; |
| 1143 | struct ftrace_page *pg; |
| 1144 | struct dyn_ftrace *rec; |
| 1145 | int type; |
| 1146 | unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
| 1147 | unsigned search_len; |
| 1148 | int not; |
| 1149 | |
| 1150 | type = ftrace_setup_glob(buff, len, &search, ¬); |
| 1151 | |
| 1152 | search_len = strlen(search); |
| 1153 | |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 1154 | /* should not be called from interrupt context */ |
| 1155 | spin_lock(&ftrace_lock); |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1156 | do_for_each_ftrace_rec(pg, rec) { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1157 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1158 | if (rec->flags & FTRACE_FL_FAILED) |
| 1159 | continue; |
Steven Rostedt | 9f4801e | 2009-02-13 15:56:43 -0500 | [diff] [blame] | 1160 | |
| 1161 | if (ftrace_match_record(rec, search, search_len, type)) { |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1162 | if (not) |
| 1163 | rec->flags &= ~flag; |
| 1164 | else |
| 1165 | rec->flags |= flag; |
| 1166 | } |
Steven Rostedt | e68746a | 2009-02-13 20:53:42 -0500 | [diff] [blame] | 1167 | /* |
| 1168 | * Only enable filtering if we have a function that |
| 1169 | * is filtered on. |
| 1170 | */ |
| 1171 | if (enable && (rec->flags & FTRACE_FL_FILTER)) |
| 1172 | ftrace_filtered = 1; |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1173 | } while_for_each_ftrace_rec(); |
Steven Rostedt | 99ecdc4 | 2008-08-15 21:40:05 -0400 | [diff] [blame] | 1174 | spin_unlock(&ftrace_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1175 | } |
| 1176 | |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1177 | static int |
| 1178 | ftrace_match_module_record(struct dyn_ftrace *rec, char *mod, |
| 1179 | char *regex, int len, int type) |
| 1180 | { |
| 1181 | char str[KSYM_SYMBOL_LEN]; |
| 1182 | char *modname; |
| 1183 | |
| 1184 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); |
| 1185 | |
| 1186 | if (!modname || strcmp(modname, mod)) |
| 1187 | return 0; |
| 1188 | |
| 1189 | /* blank search means to match all funcs in the mod */ |
| 1190 | if (len) |
| 1191 | return ftrace_match(str, regex, len, type); |
| 1192 | else |
| 1193 | return 1; |
| 1194 | } |
| 1195 | |
| 1196 | static void ftrace_match_module_records(char *buff, char *mod, int enable) |
| 1197 | { |
| 1198 | char *search = buff; |
| 1199 | struct ftrace_page *pg; |
| 1200 | struct dyn_ftrace *rec; |
| 1201 | int type = MATCH_FULL; |
| 1202 | unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
| 1203 | unsigned search_len = 0; |
| 1204 | int not = 0; |
| 1205 | |
| 1206 | /* blank or '*' mean the same */ |
| 1207 | if (strcmp(buff, "*") == 0) |
| 1208 | buff[0] = 0; |
| 1209 | |
| 1210 | /* handle the case of 'dont filter this module' */ |
| 1211 | if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { |
| 1212 | buff[0] = 0; |
| 1213 | not = 1; |
| 1214 | } |
| 1215 | |
| 1216 | if (strlen(buff)) { |
| 1217 | type = ftrace_setup_glob(buff, strlen(buff), &search, ¬); |
| 1218 | search_len = strlen(search); |
| 1219 | } |
| 1220 | |
| 1221 | /* should not be called from interrupt context */ |
| 1222 | spin_lock(&ftrace_lock); |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1223 | do_for_each_ftrace_rec(pg, rec) { |
| 1224 | |
| 1225 | if (rec->flags & FTRACE_FL_FAILED) |
| 1226 | continue; |
| 1227 | |
| 1228 | if (ftrace_match_module_record(rec, mod, |
| 1229 | search, search_len, type)) { |
| 1230 | if (not) |
| 1231 | rec->flags &= ~flag; |
| 1232 | else |
| 1233 | rec->flags |= flag; |
| 1234 | } |
Steven Rostedt | e68746a | 2009-02-13 20:53:42 -0500 | [diff] [blame] | 1235 | if (enable && (rec->flags & FTRACE_FL_FILTER)) |
| 1236 | ftrace_filtered = 1; |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1237 | |
| 1238 | } while_for_each_ftrace_rec(); |
| 1239 | spin_unlock(&ftrace_lock); |
| 1240 | } |
| 1241 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame^] | 1242 | /* |
| 1243 | * We register the module command as a template to show others how |
| 1244 | * to register the a command as well. |
| 1245 | */ |
| 1246 | |
| 1247 | static int |
| 1248 | ftrace_mod_callback(char *func, char *cmd, char *param, int enable) |
| 1249 | { |
| 1250 | char *mod; |
| 1251 | |
| 1252 | /* |
| 1253 | * cmd == 'mod' because we only registered this func |
| 1254 | * for the 'mod' ftrace_func_command. |
| 1255 | * But if you register one func with multiple commands, |
| 1256 | * you can tell which command was used by the cmd |
| 1257 | * parameter. |
| 1258 | */ |
| 1259 | |
| 1260 | /* we must have a module name */ |
| 1261 | if (!param) |
| 1262 | return -EINVAL; |
| 1263 | |
| 1264 | mod = strsep(¶m, ":"); |
| 1265 | if (!strlen(mod)) |
| 1266 | return -EINVAL; |
| 1267 | |
| 1268 | ftrace_match_module_records(func, mod, enable); |
| 1269 | return 0; |
| 1270 | } |
| 1271 | |
| 1272 | static struct ftrace_func_command ftrace_mod_cmd = { |
| 1273 | .name = "mod", |
| 1274 | .func = ftrace_mod_callback, |
| 1275 | }; |
| 1276 | |
| 1277 | static int __init ftrace_mod_cmd_init(void) |
| 1278 | { |
| 1279 | return register_ftrace_command(&ftrace_mod_cmd); |
| 1280 | } |
| 1281 | device_initcall(ftrace_mod_cmd_init); |
| 1282 | |
| 1283 | static LIST_HEAD(ftrace_commands); |
| 1284 | static DEFINE_MUTEX(ftrace_cmd_mutex); |
| 1285 | |
| 1286 | int register_ftrace_command(struct ftrace_func_command *cmd) |
| 1287 | { |
| 1288 | struct ftrace_func_command *p; |
| 1289 | int ret = 0; |
| 1290 | |
| 1291 | mutex_lock(&ftrace_cmd_mutex); |
| 1292 | list_for_each_entry(p, &ftrace_commands, list) { |
| 1293 | if (strcmp(cmd->name, p->name) == 0) { |
| 1294 | ret = -EBUSY; |
| 1295 | goto out_unlock; |
| 1296 | } |
| 1297 | } |
| 1298 | list_add(&cmd->list, &ftrace_commands); |
| 1299 | out_unlock: |
| 1300 | mutex_unlock(&ftrace_cmd_mutex); |
| 1301 | |
| 1302 | return ret; |
| 1303 | } |
| 1304 | |
| 1305 | int unregister_ftrace_command(struct ftrace_func_command *cmd) |
| 1306 | { |
| 1307 | struct ftrace_func_command *p, *n; |
| 1308 | int ret = -ENODEV; |
| 1309 | |
| 1310 | mutex_lock(&ftrace_cmd_mutex); |
| 1311 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { |
| 1312 | if (strcmp(cmd->name, p->name) == 0) { |
| 1313 | ret = 0; |
| 1314 | list_del_init(&p->list); |
| 1315 | goto out_unlock; |
| 1316 | } |
| 1317 | } |
| 1318 | out_unlock: |
| 1319 | mutex_unlock(&ftrace_cmd_mutex); |
| 1320 | |
| 1321 | return ret; |
| 1322 | } |
| 1323 | |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1324 | static int ftrace_process_regex(char *buff, int len, int enable) |
| 1325 | { |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame^] | 1326 | struct ftrace_func_command *p; |
| 1327 | char *func, *command, *next = buff; |
| 1328 | int ret = -EINVAL; |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1329 | |
| 1330 | func = strsep(&next, ":"); |
| 1331 | |
| 1332 | if (!next) { |
| 1333 | ftrace_match_records(func, len, enable); |
| 1334 | return 0; |
| 1335 | } |
| 1336 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame^] | 1337 | /* command found */ |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1338 | |
| 1339 | command = strsep(&next, ":"); |
| 1340 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame^] | 1341 | mutex_lock(&ftrace_cmd_mutex); |
| 1342 | list_for_each_entry(p, &ftrace_commands, list) { |
| 1343 | if (strcmp(p->name, command) == 0) { |
| 1344 | ret = p->func(func, command, next, enable); |
| 1345 | goto out_unlock; |
| 1346 | } |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1347 | } |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame^] | 1348 | out_unlock: |
| 1349 | mutex_unlock(&ftrace_cmd_mutex); |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1350 | |
Steven Rostedt | f618077 | 2009-02-14 00:40:25 -0500 | [diff] [blame^] | 1351 | return ret; |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1352 | } |
| 1353 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1354 | static ssize_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1355 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
| 1356 | size_t cnt, loff_t *ppos, int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1357 | { |
| 1358 | struct ftrace_iterator *iter; |
| 1359 | char ch; |
| 1360 | size_t read = 0; |
| 1361 | ssize_t ret; |
| 1362 | |
| 1363 | if (!cnt || cnt < 0) |
| 1364 | return 0; |
| 1365 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1366 | mutex_lock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1367 | |
| 1368 | if (file->f_mode & FMODE_READ) { |
| 1369 | struct seq_file *m = file->private_data; |
| 1370 | iter = m->private; |
| 1371 | } else |
| 1372 | iter = file->private_data; |
| 1373 | |
| 1374 | if (!*ppos) { |
| 1375 | iter->flags &= ~FTRACE_ITER_CONT; |
| 1376 | iter->buffer_idx = 0; |
| 1377 | } |
| 1378 | |
| 1379 | ret = get_user(ch, ubuf++); |
| 1380 | if (ret) |
| 1381 | goto out; |
| 1382 | read++; |
| 1383 | cnt--; |
| 1384 | |
| 1385 | if (!(iter->flags & ~FTRACE_ITER_CONT)) { |
| 1386 | /* skip white space */ |
| 1387 | while (cnt && isspace(ch)) { |
| 1388 | ret = get_user(ch, ubuf++); |
| 1389 | if (ret) |
| 1390 | goto out; |
| 1391 | read++; |
| 1392 | cnt--; |
| 1393 | } |
| 1394 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1395 | if (isspace(ch)) { |
| 1396 | file->f_pos += read; |
| 1397 | ret = read; |
| 1398 | goto out; |
| 1399 | } |
| 1400 | |
| 1401 | iter->buffer_idx = 0; |
| 1402 | } |
| 1403 | |
| 1404 | while (cnt && !isspace(ch)) { |
| 1405 | if (iter->buffer_idx < FTRACE_BUFF_MAX) |
| 1406 | iter->buffer[iter->buffer_idx++] = ch; |
| 1407 | else { |
| 1408 | ret = -EINVAL; |
| 1409 | goto out; |
| 1410 | } |
| 1411 | ret = get_user(ch, ubuf++); |
| 1412 | if (ret) |
| 1413 | goto out; |
| 1414 | read++; |
| 1415 | cnt--; |
| 1416 | } |
| 1417 | |
| 1418 | if (isspace(ch)) { |
| 1419 | iter->filtered++; |
| 1420 | iter->buffer[iter->buffer_idx] = 0; |
Steven Rostedt | 64e7c44 | 2009-02-13 17:08:48 -0500 | [diff] [blame] | 1421 | ret = ftrace_process_regex(iter->buffer, |
| 1422 | iter->buffer_idx, enable); |
| 1423 | if (ret) |
| 1424 | goto out; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1425 | iter->buffer_idx = 0; |
| 1426 | } else |
| 1427 | iter->flags |= FTRACE_ITER_CONT; |
| 1428 | |
| 1429 | |
| 1430 | file->f_pos += read; |
| 1431 | |
| 1432 | ret = read; |
| 1433 | out: |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1434 | mutex_unlock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1435 | |
| 1436 | return ret; |
| 1437 | } |
| 1438 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1439 | static ssize_t |
| 1440 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
| 1441 | size_t cnt, loff_t *ppos) |
| 1442 | { |
| 1443 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); |
| 1444 | } |
| 1445 | |
| 1446 | static ssize_t |
| 1447 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
| 1448 | size_t cnt, loff_t *ppos) |
| 1449 | { |
| 1450 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); |
| 1451 | } |
| 1452 | |
| 1453 | static void |
| 1454 | ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) |
| 1455 | { |
| 1456 | if (unlikely(ftrace_disabled)) |
| 1457 | return; |
| 1458 | |
| 1459 | mutex_lock(&ftrace_regex_lock); |
| 1460 | if (reset) |
| 1461 | ftrace_filter_reset(enable); |
| 1462 | if (buf) |
Steven Rostedt | 7f24b31 | 2009-02-13 14:37:33 -0500 | [diff] [blame] | 1463 | ftrace_match_records(buf, len, enable); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1464 | mutex_unlock(&ftrace_regex_lock); |
| 1465 | } |
| 1466 | |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 1467 | /** |
| 1468 | * ftrace_set_filter - set a function to filter on in ftrace |
| 1469 | * @buf - the string that holds the function filter text. |
| 1470 | * @len - the length of the string. |
| 1471 | * @reset - non zero to reset all filters before applying this filter. |
| 1472 | * |
| 1473 | * Filters denote which functions should be enabled when tracing is enabled. |
| 1474 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. |
| 1475 | */ |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1476 | void ftrace_set_filter(unsigned char *buf, int len, int reset) |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 1477 | { |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1478 | ftrace_set_regex(buf, len, reset, 1); |
| 1479 | } |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1480 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1481 | /** |
| 1482 | * ftrace_set_notrace - set a function to not trace in ftrace |
| 1483 | * @buf - the string that holds the function notrace text. |
| 1484 | * @len - the length of the string. |
| 1485 | * @reset - non zero to reset all filters before applying this filter. |
| 1486 | * |
| 1487 | * Notrace Filters denote which functions should not be enabled when tracing |
| 1488 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled |
| 1489 | * for tracing. |
| 1490 | */ |
| 1491 | void ftrace_set_notrace(unsigned char *buf, int len, int reset) |
| 1492 | { |
| 1493 | ftrace_set_regex(buf, len, reset, 0); |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 1494 | } |
| 1495 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1496 | static int |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1497 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1498 | { |
| 1499 | struct seq_file *m = (struct seq_file *)file->private_data; |
| 1500 | struct ftrace_iterator *iter; |
| 1501 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1502 | mutex_lock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1503 | if (file->f_mode & FMODE_READ) { |
| 1504 | iter = m->private; |
| 1505 | |
| 1506 | seq_release(inode, file); |
| 1507 | } else |
| 1508 | iter = file->private_data; |
| 1509 | |
| 1510 | if (iter->buffer_idx) { |
| 1511 | iter->filtered++; |
| 1512 | iter->buffer[iter->buffer_idx] = 0; |
Steven Rostedt | 7f24b31 | 2009-02-13 14:37:33 -0500 | [diff] [blame] | 1513 | ftrace_match_records(iter->buffer, iter->buffer_idx, enable); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1514 | } |
| 1515 | |
| 1516 | mutex_lock(&ftrace_sysctl_lock); |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 1517 | mutex_lock(&ftrace_start_lock); |
Steven Rostedt | ee02a2e | 2008-11-15 16:31:41 -0500 | [diff] [blame] | 1518 | if (ftrace_start_up && ftrace_enabled) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1519 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
Steven Rostedt | cb7be3b | 2008-10-23 09:33:05 -0400 | [diff] [blame] | 1520 | mutex_unlock(&ftrace_start_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1521 | mutex_unlock(&ftrace_sysctl_lock); |
| 1522 | |
| 1523 | kfree(iter); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1524 | mutex_unlock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1525 | return 0; |
| 1526 | } |
| 1527 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1528 | static int |
| 1529 | ftrace_filter_release(struct inode *inode, struct file *file) |
| 1530 | { |
| 1531 | return ftrace_regex_release(inode, file, 1); |
| 1532 | } |
| 1533 | |
| 1534 | static int |
| 1535 | ftrace_notrace_release(struct inode *inode, struct file *file) |
| 1536 | { |
| 1537 | return ftrace_regex_release(inode, file, 0); |
| 1538 | } |
| 1539 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1540 | static struct file_operations ftrace_avail_fops = { |
| 1541 | .open = ftrace_avail_open, |
| 1542 | .read = seq_read, |
| 1543 | .llseek = seq_lseek, |
| 1544 | .release = ftrace_avail_release, |
| 1545 | }; |
| 1546 | |
Abhishek Sagar | eb9a7bf | 2008-06-01 21:47:54 +0530 | [diff] [blame] | 1547 | static struct file_operations ftrace_failures_fops = { |
| 1548 | .open = ftrace_failures_open, |
| 1549 | .read = seq_read, |
| 1550 | .llseek = seq_lseek, |
| 1551 | .release = ftrace_avail_release, |
| 1552 | }; |
| 1553 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1554 | static struct file_operations ftrace_filter_fops = { |
| 1555 | .open = ftrace_filter_open, |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1556 | .read = ftrace_regex_read, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1557 | .write = ftrace_filter_write, |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1558 | .llseek = ftrace_regex_lseek, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1559 | .release = ftrace_filter_release, |
| 1560 | }; |
| 1561 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1562 | static struct file_operations ftrace_notrace_fops = { |
| 1563 | .open = ftrace_notrace_open, |
| 1564 | .read = ftrace_regex_read, |
| 1565 | .write = ftrace_notrace_write, |
| 1566 | .llseek = ftrace_regex_lseek, |
| 1567 | .release = ftrace_notrace_release, |
| 1568 | }; |
| 1569 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 1570 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
| 1571 | |
| 1572 | static DEFINE_MUTEX(graph_lock); |
| 1573 | |
| 1574 | int ftrace_graph_count; |
| 1575 | unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly; |
| 1576 | |
| 1577 | static void * |
| 1578 | g_next(struct seq_file *m, void *v, loff_t *pos) |
| 1579 | { |
| 1580 | unsigned long *array = m->private; |
| 1581 | int index = *pos; |
| 1582 | |
| 1583 | (*pos)++; |
| 1584 | |
| 1585 | if (index >= ftrace_graph_count) |
| 1586 | return NULL; |
| 1587 | |
| 1588 | return &array[index]; |
| 1589 | } |
| 1590 | |
| 1591 | static void *g_start(struct seq_file *m, loff_t *pos) |
| 1592 | { |
| 1593 | void *p = NULL; |
| 1594 | |
| 1595 | mutex_lock(&graph_lock); |
| 1596 | |
| 1597 | p = g_next(m, p, pos); |
| 1598 | |
| 1599 | return p; |
| 1600 | } |
| 1601 | |
| 1602 | static void g_stop(struct seq_file *m, void *p) |
| 1603 | { |
| 1604 | mutex_unlock(&graph_lock); |
| 1605 | } |
| 1606 | |
| 1607 | static int g_show(struct seq_file *m, void *v) |
| 1608 | { |
| 1609 | unsigned long *ptr = v; |
| 1610 | char str[KSYM_SYMBOL_LEN]; |
| 1611 | |
| 1612 | if (!ptr) |
| 1613 | return 0; |
| 1614 | |
| 1615 | kallsyms_lookup(*ptr, NULL, NULL, NULL, str); |
| 1616 | |
| 1617 | seq_printf(m, "%s\n", str); |
| 1618 | |
| 1619 | return 0; |
| 1620 | } |
| 1621 | |
| 1622 | static struct seq_operations ftrace_graph_seq_ops = { |
| 1623 | .start = g_start, |
| 1624 | .next = g_next, |
| 1625 | .stop = g_stop, |
| 1626 | .show = g_show, |
| 1627 | }; |
| 1628 | |
| 1629 | static int |
| 1630 | ftrace_graph_open(struct inode *inode, struct file *file) |
| 1631 | { |
| 1632 | int ret = 0; |
| 1633 | |
| 1634 | if (unlikely(ftrace_disabled)) |
| 1635 | return -ENODEV; |
| 1636 | |
| 1637 | mutex_lock(&graph_lock); |
| 1638 | if ((file->f_mode & FMODE_WRITE) && |
| 1639 | !(file->f_flags & O_APPEND)) { |
| 1640 | ftrace_graph_count = 0; |
| 1641 | memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs)); |
| 1642 | } |
| 1643 | |
| 1644 | if (file->f_mode & FMODE_READ) { |
| 1645 | ret = seq_open(file, &ftrace_graph_seq_ops); |
| 1646 | if (!ret) { |
| 1647 | struct seq_file *m = file->private_data; |
| 1648 | m->private = ftrace_graph_funcs; |
| 1649 | } |
| 1650 | } else |
| 1651 | file->private_data = ftrace_graph_funcs; |
| 1652 | mutex_unlock(&graph_lock); |
| 1653 | |
| 1654 | return ret; |
| 1655 | } |
| 1656 | |
| 1657 | static ssize_t |
| 1658 | ftrace_graph_read(struct file *file, char __user *ubuf, |
| 1659 | size_t cnt, loff_t *ppos) |
| 1660 | { |
| 1661 | if (file->f_mode & FMODE_READ) |
| 1662 | return seq_read(file, ubuf, cnt, ppos); |
| 1663 | else |
| 1664 | return -EPERM; |
| 1665 | } |
| 1666 | |
| 1667 | static int |
| 1668 | ftrace_set_func(unsigned long *array, int idx, char *buffer) |
| 1669 | { |
| 1670 | char str[KSYM_SYMBOL_LEN]; |
| 1671 | struct dyn_ftrace *rec; |
| 1672 | struct ftrace_page *pg; |
| 1673 | int found = 0; |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1674 | int j; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 1675 | |
| 1676 | if (ftrace_disabled) |
| 1677 | return -ENODEV; |
| 1678 | |
| 1679 | /* should not be called from interrupt context */ |
| 1680 | spin_lock(&ftrace_lock); |
| 1681 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1682 | do_for_each_ftrace_rec(pg, rec) { |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 1683 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1684 | if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) |
| 1685 | continue; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 1686 | |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1687 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
| 1688 | if (strcmp(str, buffer) == 0) { |
| 1689 | /* Return 1 if we add it to the array */ |
| 1690 | found = 1; |
| 1691 | for (j = 0; j < idx; j++) |
| 1692 | if (array[j] == rec->ip) { |
| 1693 | found = 0; |
| 1694 | break; |
| 1695 | } |
| 1696 | if (found) |
| 1697 | array[idx] = rec->ip; |
| 1698 | goto out; |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 1699 | } |
Steven Rostedt | 265c831 | 2009-02-13 12:43:56 -0500 | [diff] [blame] | 1700 | } while_for_each_ftrace_rec(); |
| 1701 | out: |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 1702 | spin_unlock(&ftrace_lock); |
| 1703 | |
| 1704 | return found ? 0 : -EINVAL; |
| 1705 | } |
| 1706 | |
| 1707 | static ssize_t |
| 1708 | ftrace_graph_write(struct file *file, const char __user *ubuf, |
| 1709 | size_t cnt, loff_t *ppos) |
| 1710 | { |
| 1711 | unsigned char buffer[FTRACE_BUFF_MAX+1]; |
| 1712 | unsigned long *array; |
| 1713 | size_t read = 0; |
| 1714 | ssize_t ret; |
| 1715 | int index = 0; |
| 1716 | char ch; |
| 1717 | |
| 1718 | if (!cnt || cnt < 0) |
| 1719 | return 0; |
| 1720 | |
| 1721 | mutex_lock(&graph_lock); |
| 1722 | |
| 1723 | if (ftrace_graph_count >= FTRACE_GRAPH_MAX_FUNCS) { |
| 1724 | ret = -EBUSY; |
| 1725 | goto out; |
| 1726 | } |
| 1727 | |
| 1728 | if (file->f_mode & FMODE_READ) { |
| 1729 | struct seq_file *m = file->private_data; |
| 1730 | array = m->private; |
| 1731 | } else |
| 1732 | array = file->private_data; |
| 1733 | |
| 1734 | ret = get_user(ch, ubuf++); |
| 1735 | if (ret) |
| 1736 | goto out; |
| 1737 | read++; |
| 1738 | cnt--; |
| 1739 | |
| 1740 | /* skip white space */ |
| 1741 | while (cnt && isspace(ch)) { |
| 1742 | ret = get_user(ch, ubuf++); |
| 1743 | if (ret) |
| 1744 | goto out; |
| 1745 | read++; |
| 1746 | cnt--; |
| 1747 | } |
| 1748 | |
| 1749 | if (isspace(ch)) { |
| 1750 | *ppos += read; |
| 1751 | ret = read; |
| 1752 | goto out; |
| 1753 | } |
| 1754 | |
| 1755 | while (cnt && !isspace(ch)) { |
| 1756 | if (index < FTRACE_BUFF_MAX) |
| 1757 | buffer[index++] = ch; |
| 1758 | else { |
| 1759 | ret = -EINVAL; |
| 1760 | goto out; |
| 1761 | } |
| 1762 | ret = get_user(ch, ubuf++); |
| 1763 | if (ret) |
| 1764 | goto out; |
| 1765 | read++; |
| 1766 | cnt--; |
| 1767 | } |
| 1768 | buffer[index] = 0; |
| 1769 | |
| 1770 | /* we allow only one at a time */ |
| 1771 | ret = ftrace_set_func(array, ftrace_graph_count, buffer); |
| 1772 | if (ret) |
| 1773 | goto out; |
| 1774 | |
| 1775 | ftrace_graph_count++; |
| 1776 | |
| 1777 | file->f_pos += read; |
| 1778 | |
| 1779 | ret = read; |
| 1780 | out: |
| 1781 | mutex_unlock(&graph_lock); |
| 1782 | |
| 1783 | return ret; |
| 1784 | } |
| 1785 | |
| 1786 | static const struct file_operations ftrace_graph_fops = { |
| 1787 | .open = ftrace_graph_open, |
| 1788 | .read = ftrace_graph_read, |
| 1789 | .write = ftrace_graph_write, |
| 1790 | }; |
| 1791 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
| 1792 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 1793 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1794 | { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1795 | struct dentry *entry; |
| 1796 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1797 | entry = debugfs_create_file("available_filter_functions", 0444, |
| 1798 | d_tracer, NULL, &ftrace_avail_fops); |
| 1799 | if (!entry) |
| 1800 | pr_warning("Could not create debugfs " |
| 1801 | "'available_filter_functions' entry\n"); |
| 1802 | |
Abhishek Sagar | eb9a7bf | 2008-06-01 21:47:54 +0530 | [diff] [blame] | 1803 | entry = debugfs_create_file("failures", 0444, |
| 1804 | d_tracer, NULL, &ftrace_failures_fops); |
| 1805 | if (!entry) |
| 1806 | pr_warning("Could not create debugfs 'failures' entry\n"); |
| 1807 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1808 | entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer, |
| 1809 | NULL, &ftrace_filter_fops); |
| 1810 | if (!entry) |
| 1811 | pr_warning("Could not create debugfs " |
| 1812 | "'set_ftrace_filter' entry\n"); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1813 | |
| 1814 | entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer, |
| 1815 | NULL, &ftrace_notrace_fops); |
| 1816 | if (!entry) |
| 1817 | pr_warning("Could not create debugfs " |
| 1818 | "'set_ftrace_notrace' entry\n"); |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 1819 | |
Steven Rostedt | ea4e2bc | 2008-12-03 15:36:57 -0500 | [diff] [blame] | 1820 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
| 1821 | entry = debugfs_create_file("set_graph_function", 0444, d_tracer, |
| 1822 | NULL, |
| 1823 | &ftrace_graph_fops); |
| 1824 | if (!entry) |
| 1825 | pr_warning("Could not create debugfs " |
| 1826 | "'set_graph_function' entry\n"); |
| 1827 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
| 1828 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1829 | return 0; |
| 1830 | } |
| 1831 | |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 1832 | static int ftrace_convert_nops(struct module *mod, |
| 1833 | unsigned long *start, |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1834 | unsigned long *end) |
| 1835 | { |
| 1836 | unsigned long *p; |
| 1837 | unsigned long addr; |
| 1838 | unsigned long flags; |
| 1839 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 1840 | mutex_lock(&ftrace_start_lock); |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1841 | p = start; |
| 1842 | while (p < end) { |
| 1843 | addr = ftrace_call_adjust(*p++); |
Steven Rostedt | 20e5227 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 1844 | /* |
| 1845 | * Some architecture linkers will pad between |
| 1846 | * the different mcount_loc sections of different |
| 1847 | * object files to satisfy alignments. |
| 1848 | * Skip any NULL pointers. |
| 1849 | */ |
| 1850 | if (!addr) |
| 1851 | continue; |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1852 | ftrace_record_ip(addr); |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1853 | } |
| 1854 | |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 1855 | /* disable interrupts to prevent kstop machine */ |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1856 | local_irq_save(flags); |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 1857 | ftrace_update_code(mod); |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1858 | local_irq_restore(flags); |
Steven Rostedt | 08f5ac90 | 2008-10-23 09:33:07 -0400 | [diff] [blame] | 1859 | mutex_unlock(&ftrace_start_lock); |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1860 | |
| 1861 | return 0; |
| 1862 | } |
| 1863 | |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 1864 | void ftrace_init_module(struct module *mod, |
| 1865 | unsigned long *start, unsigned long *end) |
Steven Rostedt | 90d595f | 2008-08-14 15:45:09 -0400 | [diff] [blame] | 1866 | { |
Steven Rostedt | 00fd61a | 2008-08-15 21:40:04 -0400 | [diff] [blame] | 1867 | if (ftrace_disabled || start == end) |
Steven Rostedt | fed1939 | 2008-08-14 22:47:19 -0400 | [diff] [blame] | 1868 | return; |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 1869 | ftrace_convert_nops(mod, start, end); |
Steven Rostedt | 90d595f | 2008-08-14 15:45:09 -0400 | [diff] [blame] | 1870 | } |
| 1871 | |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1872 | extern unsigned long __start_mcount_loc[]; |
| 1873 | extern unsigned long __stop_mcount_loc[]; |
| 1874 | |
| 1875 | void __init ftrace_init(void) |
| 1876 | { |
| 1877 | unsigned long count, addr, flags; |
| 1878 | int ret; |
| 1879 | |
| 1880 | /* Keep the ftrace pointer to the stub */ |
| 1881 | addr = (unsigned long)ftrace_stub; |
| 1882 | |
| 1883 | local_irq_save(flags); |
| 1884 | ftrace_dyn_arch_init(&addr); |
| 1885 | local_irq_restore(flags); |
| 1886 | |
| 1887 | /* ftrace_dyn_arch_init places the return code in addr */ |
| 1888 | if (addr) |
| 1889 | goto failed; |
| 1890 | |
| 1891 | count = __stop_mcount_loc - __start_mcount_loc; |
| 1892 | |
| 1893 | ret = ftrace_dyn_table_alloc(count); |
| 1894 | if (ret) |
| 1895 | goto failed; |
| 1896 | |
| 1897 | last_ftrace_enabled = ftrace_enabled = 1; |
| 1898 | |
Steven Rostedt | 31e8890 | 2008-11-14 16:21:19 -0800 | [diff] [blame] | 1899 | ret = ftrace_convert_nops(NULL, |
| 1900 | __start_mcount_loc, |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1901 | __stop_mcount_loc); |
| 1902 | |
| 1903 | return; |
| 1904 | failed: |
| 1905 | ftrace_disabled = 1; |
| 1906 | } |
Steven Rostedt | 68bf21a | 2008-08-14 15:45:08 -0400 | [diff] [blame] | 1907 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1908 | #else |
Frederic Weisbecker | 0b6e4d5 | 2008-10-28 20:17:38 +0100 | [diff] [blame] | 1909 | |
| 1910 | static int __init ftrace_nodyn_init(void) |
| 1911 | { |
| 1912 | ftrace_enabled = 1; |
| 1913 | return 0; |
| 1914 | } |
| 1915 | device_initcall(ftrace_nodyn_init); |
| 1916 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 1917 | static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } |
| 1918 | static inline void ftrace_startup_enable(int command) { } |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 1919 | /* Keep as macros so we do not need to define the commands */ |
| 1920 | # define ftrace_startup(command) do { } while (0) |
| 1921 | # define ftrace_shutdown(command) do { } while (0) |
Ingo Molnar | c7aafc5 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 1922 | # define ftrace_startup_sysctl() do { } while (0) |
| 1923 | # define ftrace_shutdown_sysctl() do { } while (0) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1924 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
| 1925 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 1926 | static ssize_t |
| 1927 | ftrace_pid_read(struct file *file, char __user *ubuf, |
| 1928 | size_t cnt, loff_t *ppos) |
| 1929 | { |
| 1930 | char buf[64]; |
| 1931 | int r; |
| 1932 | |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 1933 | if (ftrace_pid_trace == ftrace_swapper_pid) |
| 1934 | r = sprintf(buf, "swapper tasks\n"); |
| 1935 | else if (ftrace_pid_trace) |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 1936 | r = sprintf(buf, "%u\n", pid_nr(ftrace_pid_trace)); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 1937 | else |
| 1938 | r = sprintf(buf, "no pid\n"); |
| 1939 | |
| 1940 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
| 1941 | } |
| 1942 | |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 1943 | static void clear_ftrace_swapper(void) |
| 1944 | { |
| 1945 | struct task_struct *p; |
| 1946 | int cpu; |
| 1947 | |
| 1948 | get_online_cpus(); |
| 1949 | for_each_online_cpu(cpu) { |
| 1950 | p = idle_task(cpu); |
| 1951 | clear_tsk_trace_trace(p); |
| 1952 | } |
| 1953 | put_online_cpus(); |
| 1954 | } |
| 1955 | |
| 1956 | static void set_ftrace_swapper(void) |
| 1957 | { |
| 1958 | struct task_struct *p; |
| 1959 | int cpu; |
| 1960 | |
| 1961 | get_online_cpus(); |
| 1962 | for_each_online_cpu(cpu) { |
| 1963 | p = idle_task(cpu); |
| 1964 | set_tsk_trace_trace(p); |
| 1965 | } |
| 1966 | put_online_cpus(); |
| 1967 | } |
| 1968 | |
| 1969 | static void clear_ftrace_pid(struct pid *pid) |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 1970 | { |
| 1971 | struct task_struct *p; |
| 1972 | |
Oleg Nesterov | 229c4ef | 2009-02-03 20:39:04 +0100 | [diff] [blame] | 1973 | rcu_read_lock(); |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 1974 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 1975 | clear_tsk_trace_trace(p); |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 1976 | } while_each_pid_task(pid, PIDTYPE_PID, p); |
Oleg Nesterov | 229c4ef | 2009-02-03 20:39:04 +0100 | [diff] [blame] | 1977 | rcu_read_unlock(); |
| 1978 | |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 1979 | put_pid(pid); |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 1980 | } |
| 1981 | |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 1982 | static void set_ftrace_pid(struct pid *pid) |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 1983 | { |
| 1984 | struct task_struct *p; |
| 1985 | |
Oleg Nesterov | 229c4ef | 2009-02-03 20:39:04 +0100 | [diff] [blame] | 1986 | rcu_read_lock(); |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 1987 | do_each_pid_task(pid, PIDTYPE_PID, p) { |
| 1988 | set_tsk_trace_trace(p); |
| 1989 | } while_each_pid_task(pid, PIDTYPE_PID, p); |
Oleg Nesterov | 229c4ef | 2009-02-03 20:39:04 +0100 | [diff] [blame] | 1990 | rcu_read_unlock(); |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 1991 | } |
| 1992 | |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 1993 | static void clear_ftrace_pid_task(struct pid **pid) |
| 1994 | { |
| 1995 | if (*pid == ftrace_swapper_pid) |
| 1996 | clear_ftrace_swapper(); |
| 1997 | else |
| 1998 | clear_ftrace_pid(*pid); |
| 1999 | |
| 2000 | *pid = NULL; |
| 2001 | } |
| 2002 | |
| 2003 | static void set_ftrace_pid_task(struct pid *pid) |
| 2004 | { |
| 2005 | if (pid == ftrace_swapper_pid) |
| 2006 | set_ftrace_swapper(); |
| 2007 | else |
| 2008 | set_ftrace_pid(pid); |
| 2009 | } |
| 2010 | |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2011 | static ssize_t |
| 2012 | ftrace_pid_write(struct file *filp, const char __user *ubuf, |
| 2013 | size_t cnt, loff_t *ppos) |
| 2014 | { |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 2015 | struct pid *pid; |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2016 | char buf[64]; |
| 2017 | long val; |
| 2018 | int ret; |
| 2019 | |
| 2020 | if (cnt >= sizeof(buf)) |
| 2021 | return -EINVAL; |
| 2022 | |
| 2023 | if (copy_from_user(&buf, ubuf, cnt)) |
| 2024 | return -EFAULT; |
| 2025 | |
| 2026 | buf[cnt] = 0; |
| 2027 | |
| 2028 | ret = strict_strtol(buf, 10, &val); |
| 2029 | if (ret < 0) |
| 2030 | return ret; |
| 2031 | |
| 2032 | mutex_lock(&ftrace_start_lock); |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 2033 | if (val < 0) { |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2034 | /* disable pid tracing */ |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 2035 | if (!ftrace_pid_trace) |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2036 | goto out; |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 2037 | |
| 2038 | clear_ftrace_pid_task(&ftrace_pid_trace); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2039 | |
| 2040 | } else { |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 2041 | /* swapper task is special */ |
| 2042 | if (!val) { |
| 2043 | pid = ftrace_swapper_pid; |
| 2044 | if (pid == ftrace_pid_trace) |
| 2045 | goto out; |
| 2046 | } else { |
| 2047 | pid = find_get_pid(val); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2048 | |
Steven Rostedt | e32d895 | 2008-12-04 00:26:41 -0500 | [diff] [blame] | 2049 | if (pid == ftrace_pid_trace) { |
| 2050 | put_pid(pid); |
| 2051 | goto out; |
| 2052 | } |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 2053 | } |
| 2054 | |
| 2055 | if (ftrace_pid_trace) |
| 2056 | clear_ftrace_pid_task(&ftrace_pid_trace); |
| 2057 | |
| 2058 | if (!pid) |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2059 | goto out; |
| 2060 | |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 2061 | ftrace_pid_trace = pid; |
Steven Rostedt | 0ef8cde | 2008-12-03 15:36:58 -0500 | [diff] [blame] | 2062 | |
Steven Rostedt | 978f3a4 | 2008-12-04 00:26:40 -0500 | [diff] [blame] | 2063 | set_ftrace_pid_task(ftrace_pid_trace); |
Steven Rostedt | df4fc31 | 2008-11-26 00:16:23 -0500 | [diff] [blame] | 2064 | } |
| 2065 | |
| 2066 | /* update the function call */ |
| 2067 | ftrace_update_pid_func(); |
| 2068 | ftrace_startup_enable(0); |
| 2069 | |
| 2070 | out: |
| 2071 | mutex_unlock(&ftrace_start_lock); |
| 2072 | |
| 2073 | return cnt; |
| 2074 | } |
| 2075 | |
| 2076 | static struct file_operations ftrace_pid_fops = { |
| 2077 | .read = ftrace_pid_read, |
| 2078 | .write = ftrace_pid_write, |
| 2079 | }; |
| 2080 | |
| 2081 | static __init int ftrace_init_debugfs(void) |
| 2082 | { |
| 2083 | struct dentry *d_tracer; |
| 2084 | struct dentry *entry; |
| 2085 | |
| 2086 | d_tracer = tracing_init_dentry(); |
| 2087 | if (!d_tracer) |
| 2088 | return 0; |
| 2089 | |
| 2090 | ftrace_init_dyn_debugfs(d_tracer); |
| 2091 | |
| 2092 | entry = debugfs_create_file("set_ftrace_pid", 0644, d_tracer, |
| 2093 | NULL, &ftrace_pid_fops); |
| 2094 | if (!entry) |
| 2095 | pr_warning("Could not create debugfs " |
| 2096 | "'set_ftrace_pid' entry\n"); |
| 2097 | return 0; |
| 2098 | } |
| 2099 | |
| 2100 | fs_initcall(ftrace_init_debugfs); |
| 2101 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2102 | /** |
Steven Rostedt | 81adbdc | 2008-10-23 09:33:02 -0400 | [diff] [blame] | 2103 | * ftrace_kill - kill ftrace |
Steven Rostedt | a2bb6a3 | 2008-07-10 20:58:15 -0400 | [diff] [blame] | 2104 | * |
| 2105 | * This function should be used by panic code. It stops ftrace |
| 2106 | * but in a not so nice way. If you need to simply kill ftrace |
| 2107 | * from a non-atomic section, use ftrace_kill. |
| 2108 | */ |
Steven Rostedt | 81adbdc | 2008-10-23 09:33:02 -0400 | [diff] [blame] | 2109 | void ftrace_kill(void) |
Steven Rostedt | a2bb6a3 | 2008-07-10 20:58:15 -0400 | [diff] [blame] | 2110 | { |
| 2111 | ftrace_disabled = 1; |
| 2112 | ftrace_enabled = 0; |
Steven Rostedt | a2bb6a3 | 2008-07-10 20:58:15 -0400 | [diff] [blame] | 2113 | clear_ftrace_function(); |
| 2114 | } |
| 2115 | |
| 2116 | /** |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2117 | * register_ftrace_function - register a function for profiling |
| 2118 | * @ops - ops structure that holds the function for profiling. |
| 2119 | * |
| 2120 | * Register a function to be called by all functions in the |
| 2121 | * kernel. |
| 2122 | * |
| 2123 | * Note: @ops->func and all the functions it calls must be labeled |
| 2124 | * with "notrace", otherwise it will go into a |
| 2125 | * recursive loop. |
| 2126 | */ |
| 2127 | int register_ftrace_function(struct ftrace_ops *ops) |
| 2128 | { |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2129 | int ret; |
| 2130 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 2131 | if (unlikely(ftrace_disabled)) |
| 2132 | return -1; |
| 2133 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2134 | mutex_lock(&ftrace_sysctl_lock); |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 2135 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2136 | ret = __register_ftrace_function(ops); |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 2137 | ftrace_startup(0); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2138 | |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 2139 | mutex_unlock(&ftrace_sysctl_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2140 | return ret; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2141 | } |
| 2142 | |
| 2143 | /** |
Uwe Kleine-Koenig | 3263292 | 2009-01-12 23:35:50 +0100 | [diff] [blame] | 2144 | * unregister_ftrace_function - unregister a function for profiling. |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2145 | * @ops - ops structure that holds the function to unregister |
| 2146 | * |
| 2147 | * Unregister a function that was added to be called by ftrace profiling. |
| 2148 | */ |
| 2149 | int unregister_ftrace_function(struct ftrace_ops *ops) |
| 2150 | { |
| 2151 | int ret; |
| 2152 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2153 | mutex_lock(&ftrace_sysctl_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2154 | ret = __unregister_ftrace_function(ops); |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 2155 | ftrace_shutdown(0); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2156 | mutex_unlock(&ftrace_sysctl_lock); |
| 2157 | |
| 2158 | return ret; |
| 2159 | } |
| 2160 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 2161 | int |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2162 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2163 | struct file *file, void __user *buffer, size_t *lenp, |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2164 | loff_t *ppos) |
| 2165 | { |
| 2166 | int ret; |
| 2167 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 2168 | if (unlikely(ftrace_disabled)) |
| 2169 | return -ENODEV; |
| 2170 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2171 | mutex_lock(&ftrace_sysctl_lock); |
| 2172 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2173 | ret = proc_dointvec(table, write, file, buffer, lenp, ppos); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 2174 | |
| 2175 | if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) |
| 2176 | goto out; |
| 2177 | |
| 2178 | last_ftrace_enabled = ftrace_enabled; |
| 2179 | |
| 2180 | if (ftrace_enabled) { |
| 2181 | |
| 2182 | ftrace_startup_sysctl(); |
| 2183 | |
| 2184 | /* we are starting ftrace again */ |
| 2185 | if (ftrace_list != &ftrace_list_end) { |
| 2186 | if (ftrace_list->next == &ftrace_list_end) |
| 2187 | ftrace_trace_function = ftrace_list->func; |
| 2188 | else |
| 2189 | ftrace_trace_function = ftrace_list_func; |
| 2190 | } |
| 2191 | |
| 2192 | } else { |
| 2193 | /* stopping ftrace calls (just send to ftrace_stub) */ |
| 2194 | ftrace_trace_function = ftrace_stub; |
| 2195 | |
| 2196 | ftrace_shutdown_sysctl(); |
| 2197 | } |
| 2198 | |
| 2199 | out: |
| 2200 | mutex_unlock(&ftrace_sysctl_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2201 | return ret; |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 2202 | } |
Ingo Molnar | f17845e | 2008-10-24 12:47:10 +0200 | [diff] [blame] | 2203 | |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 2204 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 2205 | |
Frederic Weisbecker | 287b6e6 | 2008-11-26 00:57:25 +0100 | [diff] [blame] | 2206 | static atomic_t ftrace_graph_active; |
Frederic Weisbecker | 4a2b8dd | 2009-01-14 13:33:27 -0800 | [diff] [blame] | 2207 | static struct notifier_block ftrace_suspend_notifier; |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2208 | |
Steven Rostedt | e49dc19 | 2008-12-02 23:50:05 -0500 | [diff] [blame] | 2209 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
| 2210 | { |
| 2211 | return 0; |
| 2212 | } |
| 2213 | |
Frederic Weisbecker | 287b6e6 | 2008-11-26 00:57:25 +0100 | [diff] [blame] | 2214 | /* The callbacks that hook a function */ |
| 2215 | trace_func_graph_ret_t ftrace_graph_return = |
| 2216 | (trace_func_graph_ret_t)ftrace_stub; |
Steven Rostedt | e49dc19 | 2008-12-02 23:50:05 -0500 | [diff] [blame] | 2217 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2218 | |
| 2219 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ |
| 2220 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) |
| 2221 | { |
| 2222 | int i; |
| 2223 | int ret = 0; |
| 2224 | unsigned long flags; |
| 2225 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; |
| 2226 | struct task_struct *g, *t; |
| 2227 | |
| 2228 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { |
| 2229 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH |
| 2230 | * sizeof(struct ftrace_ret_stack), |
| 2231 | GFP_KERNEL); |
| 2232 | if (!ret_stack_list[i]) { |
| 2233 | start = 0; |
| 2234 | end = i; |
| 2235 | ret = -ENOMEM; |
| 2236 | goto free; |
| 2237 | } |
| 2238 | } |
| 2239 | |
| 2240 | read_lock_irqsave(&tasklist_lock, flags); |
| 2241 | do_each_thread(g, t) { |
| 2242 | if (start == end) { |
| 2243 | ret = -EAGAIN; |
| 2244 | goto unlock; |
| 2245 | } |
| 2246 | |
| 2247 | if (t->ret_stack == NULL) { |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2248 | t->curr_ret_stack = -1; |
Frederic Weisbecker | 48d68b2 | 2008-12-02 00:20:39 +0100 | [diff] [blame] | 2249 | /* Make sure IRQs see the -1 first: */ |
| 2250 | barrier(); |
| 2251 | t->ret_stack = ret_stack_list[start++]; |
Frederic Weisbecker | 380c4b1 | 2008-12-06 03:43:41 +0100 | [diff] [blame] | 2252 | atomic_set(&t->tracing_graph_pause, 0); |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2253 | atomic_set(&t->trace_overrun, 0); |
| 2254 | } |
| 2255 | } while_each_thread(g, t); |
| 2256 | |
| 2257 | unlock: |
| 2258 | read_unlock_irqrestore(&tasklist_lock, flags); |
| 2259 | free: |
| 2260 | for (i = start; i < end; i++) |
| 2261 | kfree(ret_stack_list[i]); |
| 2262 | return ret; |
| 2263 | } |
| 2264 | |
| 2265 | /* Allocate a return stack for each task */ |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 2266 | static int start_graph_tracing(void) |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2267 | { |
| 2268 | struct ftrace_ret_stack **ret_stack_list; |
| 2269 | int ret; |
| 2270 | |
| 2271 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * |
| 2272 | sizeof(struct ftrace_ret_stack *), |
| 2273 | GFP_KERNEL); |
| 2274 | |
| 2275 | if (!ret_stack_list) |
| 2276 | return -ENOMEM; |
| 2277 | |
| 2278 | do { |
| 2279 | ret = alloc_retstack_tasklist(ret_stack_list); |
| 2280 | } while (ret == -EAGAIN); |
| 2281 | |
| 2282 | kfree(ret_stack_list); |
| 2283 | return ret; |
| 2284 | } |
| 2285 | |
Frederic Weisbecker | 4a2b8dd | 2009-01-14 13:33:27 -0800 | [diff] [blame] | 2286 | /* |
| 2287 | * Hibernation protection. |
| 2288 | * The state of the current task is too much unstable during |
| 2289 | * suspend/restore to disk. We want to protect against that. |
| 2290 | */ |
| 2291 | static int |
| 2292 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, |
| 2293 | void *unused) |
| 2294 | { |
| 2295 | switch (state) { |
| 2296 | case PM_HIBERNATION_PREPARE: |
| 2297 | pause_graph_tracing(); |
| 2298 | break; |
| 2299 | |
| 2300 | case PM_POST_HIBERNATION: |
| 2301 | unpause_graph_tracing(); |
| 2302 | break; |
| 2303 | } |
| 2304 | return NOTIFY_DONE; |
| 2305 | } |
| 2306 | |
Frederic Weisbecker | 287b6e6 | 2008-11-26 00:57:25 +0100 | [diff] [blame] | 2307 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
| 2308 | trace_func_graph_ent_t entryfunc) |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 2309 | { |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 2310 | int ret = 0; |
| 2311 | |
| 2312 | mutex_lock(&ftrace_sysctl_lock); |
| 2313 | |
Frederic Weisbecker | 4a2b8dd | 2009-01-14 13:33:27 -0800 | [diff] [blame] | 2314 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
| 2315 | register_pm_notifier(&ftrace_suspend_notifier); |
| 2316 | |
Frederic Weisbecker | 287b6e6 | 2008-11-26 00:57:25 +0100 | [diff] [blame] | 2317 | atomic_inc(&ftrace_graph_active); |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 2318 | ret = start_graph_tracing(); |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2319 | if (ret) { |
Frederic Weisbecker | 287b6e6 | 2008-11-26 00:57:25 +0100 | [diff] [blame] | 2320 | atomic_dec(&ftrace_graph_active); |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2321 | goto out; |
| 2322 | } |
Steven Rostedt | e53a631 | 2008-11-26 00:16:25 -0500 | [diff] [blame] | 2323 | |
Frederic Weisbecker | 287b6e6 | 2008-11-26 00:57:25 +0100 | [diff] [blame] | 2324 | ftrace_graph_return = retfunc; |
| 2325 | ftrace_graph_entry = entryfunc; |
Steven Rostedt | e53a631 | 2008-11-26 00:16:25 -0500 | [diff] [blame] | 2326 | |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 2327 | ftrace_startup(FTRACE_START_FUNC_RET); |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 2328 | |
| 2329 | out: |
| 2330 | mutex_unlock(&ftrace_sysctl_lock); |
| 2331 | return ret; |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 2332 | } |
| 2333 | |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 2334 | void unregister_ftrace_graph(void) |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 2335 | { |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 2336 | mutex_lock(&ftrace_sysctl_lock); |
| 2337 | |
Frederic Weisbecker | 287b6e6 | 2008-11-26 00:57:25 +0100 | [diff] [blame] | 2338 | atomic_dec(&ftrace_graph_active); |
| 2339 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
Steven Rostedt | e49dc19 | 2008-12-02 23:50:05 -0500 | [diff] [blame] | 2340 | ftrace_graph_entry = ftrace_graph_entry_stub; |
Steven Rostedt | 5a45cfe | 2008-11-26 00:16:24 -0500 | [diff] [blame] | 2341 | ftrace_shutdown(FTRACE_STOP_FUNC_RET); |
Frederic Weisbecker | 4a2b8dd | 2009-01-14 13:33:27 -0800 | [diff] [blame] | 2342 | unregister_pm_notifier(&ftrace_suspend_notifier); |
Frederic Weisbecker | e7d3737 | 2008-11-16 06:02:06 +0100 | [diff] [blame] | 2343 | |
| 2344 | mutex_unlock(&ftrace_sysctl_lock); |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 2345 | } |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2346 | |
| 2347 | /* Allocate a return stack for newly created task */ |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 2348 | void ftrace_graph_init_task(struct task_struct *t) |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2349 | { |
Frederic Weisbecker | 287b6e6 | 2008-11-26 00:57:25 +0100 | [diff] [blame] | 2350 | if (atomic_read(&ftrace_graph_active)) { |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2351 | t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH |
| 2352 | * sizeof(struct ftrace_ret_stack), |
| 2353 | GFP_KERNEL); |
| 2354 | if (!t->ret_stack) |
| 2355 | return; |
| 2356 | t->curr_ret_stack = -1; |
Frederic Weisbecker | 380c4b1 | 2008-12-06 03:43:41 +0100 | [diff] [blame] | 2357 | atomic_set(&t->tracing_graph_pause, 0); |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2358 | atomic_set(&t->trace_overrun, 0); |
| 2359 | } else |
| 2360 | t->ret_stack = NULL; |
| 2361 | } |
| 2362 | |
Frederic Weisbecker | fb52607 | 2008-11-25 21:07:04 +0100 | [diff] [blame] | 2363 | void ftrace_graph_exit_task(struct task_struct *t) |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2364 | { |
Frederic Weisbecker | eae849c | 2008-11-23 17:33:12 +0100 | [diff] [blame] | 2365 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
| 2366 | |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2367 | t->ret_stack = NULL; |
Frederic Weisbecker | eae849c | 2008-11-23 17:33:12 +0100 | [diff] [blame] | 2368 | /* NULL must become visible to IRQs before we free it: */ |
| 2369 | barrier(); |
| 2370 | |
| 2371 | kfree(ret_stack); |
Frederic Weisbecker | f201ae2 | 2008-11-23 06:22:56 +0100 | [diff] [blame] | 2372 | } |
Steven Rostedt | 14a866c | 2008-12-02 23:50:02 -0500 | [diff] [blame] | 2373 | |
| 2374 | void ftrace_graph_stop(void) |
| 2375 | { |
| 2376 | ftrace_stop(); |
| 2377 | } |
Frederic Weisbecker | 15e6cb3 | 2008-11-11 07:14:25 +0100 | [diff] [blame] | 2378 | #endif |
| 2379 | |