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> |
| 20 | #include <linux/debugfs.h> |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 21 | #include <linux/hardirq.h> |
Ingo Molnar | 2d8b820 | 2008-02-23 16:55:50 +0100 | [diff] [blame] | 22 | #include <linux/kthread.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 23 | #include <linux/uaccess.h> |
Ingo Molnar | 2d8b820 | 2008-02-23 16:55:50 +0100 | [diff] [blame] | 24 | #include <linux/ftrace.h> |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 25 | #include <linux/sysctl.h> |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 26 | #include <linux/ctype.h> |
Ingo Molnar | 2d8b820 | 2008-02-23 16:55:50 +0100 | [diff] [blame] | 27 | #include <linux/hash.h> |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 28 | #include <linux/list.h> |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 29 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 30 | #include "trace.h" |
| 31 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 32 | /* ftrace_enabled is a method to turn ftrace on or off */ |
| 33 | int ftrace_enabled __read_mostly; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 34 | static int last_ftrace_enabled; |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 35 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 36 | /* |
| 37 | * ftrace_disabled is set when an anomaly is discovered. |
| 38 | * ftrace_disabled is much stronger than ftrace_enabled. |
| 39 | */ |
| 40 | static int ftrace_disabled __read_mostly; |
| 41 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 42 | static DEFINE_SPINLOCK(ftrace_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 43 | static DEFINE_MUTEX(ftrace_sysctl_lock); |
| 44 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 45 | static struct ftrace_ops ftrace_list_end __read_mostly = |
| 46 | { |
| 47 | .func = ftrace_stub, |
| 48 | }; |
| 49 | |
| 50 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; |
| 51 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
| 52 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 53 | 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] | 54 | { |
| 55 | struct ftrace_ops *op = ftrace_list; |
| 56 | |
| 57 | /* in case someone actually ports this to alpha! */ |
| 58 | read_barrier_depends(); |
| 59 | |
| 60 | while (op != &ftrace_list_end) { |
| 61 | /* silly alpha */ |
| 62 | read_barrier_depends(); |
| 63 | op->func(ip, parent_ip); |
| 64 | op = op->next; |
| 65 | }; |
| 66 | } |
| 67 | |
| 68 | /** |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 69 | * clear_ftrace_function - reset the ftrace function |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 70 | * |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 71 | * This NULLs the ftrace function and in essence stops |
| 72 | * tracing. There may be lag |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 73 | */ |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 74 | void clear_ftrace_function(void) |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 75 | { |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 76 | ftrace_trace_function = ftrace_stub; |
| 77 | } |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 78 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 79 | static int __register_ftrace_function(struct ftrace_ops *ops) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 80 | { |
| 81 | /* Should never be called by interrupts */ |
| 82 | spin_lock(&ftrace_lock); |
| 83 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 84 | ops->next = ftrace_list; |
| 85 | /* |
| 86 | * We are entering ops into the ftrace_list but another |
| 87 | * CPU might be walking that list. We need to make sure |
| 88 | * the ops->next pointer is valid before another CPU sees |
| 89 | * the ops pointer included into the ftrace_list. |
| 90 | */ |
| 91 | smp_wmb(); |
| 92 | ftrace_list = ops; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 93 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 94 | if (ftrace_enabled) { |
| 95 | /* |
| 96 | * For one func, simply call it directly. |
| 97 | * For more than one func, call the chain. |
| 98 | */ |
| 99 | if (ops->next == &ftrace_list_end) |
| 100 | ftrace_trace_function = ops->func; |
| 101 | else |
| 102 | ftrace_trace_function = ftrace_list_func; |
| 103 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 104 | |
| 105 | spin_unlock(&ftrace_lock); |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 106 | |
| 107 | return 0; |
| 108 | } |
| 109 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 110 | static int __unregister_ftrace_function(struct ftrace_ops *ops) |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 111 | { |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 112 | struct ftrace_ops **p; |
| 113 | int ret = 0; |
| 114 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 115 | spin_lock(&ftrace_lock); |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 116 | |
| 117 | /* |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 118 | * If we are removing the last function, then simply point |
| 119 | * to the ftrace_stub. |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 120 | */ |
| 121 | if (ftrace_list == ops && ops->next == &ftrace_list_end) { |
| 122 | ftrace_trace_function = ftrace_stub; |
| 123 | ftrace_list = &ftrace_list_end; |
| 124 | goto out; |
| 125 | } |
| 126 | |
| 127 | for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) |
| 128 | if (*p == ops) |
| 129 | break; |
| 130 | |
| 131 | if (*p != ops) { |
| 132 | ret = -1; |
| 133 | goto out; |
| 134 | } |
| 135 | |
| 136 | *p = (*p)->next; |
| 137 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 138 | if (ftrace_enabled) { |
| 139 | /* If we only have one func left, then call that directly */ |
| 140 | if (ftrace_list == &ftrace_list_end || |
| 141 | ftrace_list->next == &ftrace_list_end) |
| 142 | ftrace_trace_function = ftrace_list->func; |
| 143 | } |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 144 | |
| 145 | out: |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 146 | spin_unlock(&ftrace_lock); |
| 147 | |
| 148 | return ret; |
| 149 | } |
| 150 | |
| 151 | #ifdef CONFIG_DYNAMIC_FTRACE |
| 152 | |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 153 | static struct task_struct *ftraced_task; |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 154 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 155 | enum { |
| 156 | FTRACE_ENABLE_CALLS = (1 << 0), |
| 157 | FTRACE_DISABLE_CALLS = (1 << 1), |
| 158 | FTRACE_UPDATE_TRACE_FUNC = (1 << 2), |
| 159 | FTRACE_ENABLE_MCOUNT = (1 << 3), |
| 160 | FTRACE_DISABLE_MCOUNT = (1 << 4), |
| 161 | }; |
| 162 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 163 | static int ftrace_filtered; |
| 164 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 165 | static struct hlist_head ftrace_hash[FTRACE_HASHSIZE]; |
| 166 | |
| 167 | static DEFINE_PER_CPU(int, ftrace_shutdown_disable_cpu); |
| 168 | |
| 169 | static DEFINE_SPINLOCK(ftrace_shutdown_lock); |
| 170 | static DEFINE_MUTEX(ftraced_lock); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 171 | static DEFINE_MUTEX(ftrace_regex_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 172 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 173 | struct ftrace_page { |
| 174 | struct ftrace_page *next; |
David Miller | aa5e5ce | 2008-05-13 22:06:56 -0700 | [diff] [blame] | 175 | unsigned long index; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 176 | struct dyn_ftrace records[]; |
David Miller | aa5e5ce | 2008-05-13 22:06:56 -0700 | [diff] [blame] | 177 | }; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 178 | |
| 179 | #define ENTRIES_PER_PAGE \ |
| 180 | ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace)) |
| 181 | |
| 182 | /* estimate from running different kernels */ |
| 183 | #define NR_TO_INIT 10000 |
| 184 | |
| 185 | static struct ftrace_page *ftrace_pages_start; |
| 186 | static struct ftrace_page *ftrace_pages; |
| 187 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 188 | static int ftraced_trigger; |
| 189 | static int ftraced_suspend; |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 190 | static int ftraced_stop; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 191 | |
| 192 | static int ftrace_record_suspend; |
| 193 | |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 194 | static struct dyn_ftrace *ftrace_free_records; |
| 195 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 196 | static inline int |
Ingo Molnar | 9ff9cdb | 2008-05-12 21:20:50 +0200 | [diff] [blame] | 197 | ftrace_ip_in_hash(unsigned long ip, unsigned long key) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 198 | { |
| 199 | struct dyn_ftrace *p; |
| 200 | struct hlist_node *t; |
| 201 | int found = 0; |
| 202 | |
Abhishek Sagar | ffdaa35 | 2008-05-24 23:45:02 +0530 | [diff] [blame] | 203 | hlist_for_each_entry_rcu(p, t, &ftrace_hash[key], node) { |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 204 | if (p->ip == ip) { |
| 205 | found = 1; |
| 206 | break; |
| 207 | } |
| 208 | } |
| 209 | |
| 210 | return found; |
| 211 | } |
| 212 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 213 | static inline void |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 214 | ftrace_add_hash(struct dyn_ftrace *node, unsigned long key) |
| 215 | { |
Abhishek Sagar | ffdaa35 | 2008-05-24 23:45:02 +0530 | [diff] [blame] | 216 | hlist_add_head_rcu(&node->node, &ftrace_hash[key]); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 217 | } |
| 218 | |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 219 | /* called from kstop_machine */ |
| 220 | static inline void ftrace_del_hash(struct dyn_ftrace *node) |
| 221 | { |
| 222 | hlist_del(&node->node); |
| 223 | } |
| 224 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 225 | static void ftrace_free_rec(struct dyn_ftrace *rec) |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 226 | { |
| 227 | /* no locking, only called from kstop_machine */ |
| 228 | |
| 229 | rec->ip = (unsigned long)ftrace_free_records; |
| 230 | ftrace_free_records = rec; |
| 231 | rec->flags |= FTRACE_FL_FREE; |
| 232 | } |
| 233 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 234 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 235 | { |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 236 | struct dyn_ftrace *rec; |
| 237 | |
| 238 | /* First check for freed records */ |
| 239 | if (ftrace_free_records) { |
| 240 | rec = ftrace_free_records; |
| 241 | |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 242 | if (unlikely(!(rec->flags & FTRACE_FL_FREE))) { |
| 243 | WARN_ON_ONCE(1); |
| 244 | ftrace_free_records = NULL; |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 245 | ftrace_disabled = 1; |
| 246 | ftrace_enabled = 0; |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 247 | return NULL; |
| 248 | } |
| 249 | |
| 250 | ftrace_free_records = (void *)rec->ip; |
| 251 | memset(rec, 0, sizeof(*rec)); |
| 252 | return rec; |
| 253 | } |
| 254 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 255 | if (ftrace_pages->index == ENTRIES_PER_PAGE) { |
| 256 | if (!ftrace_pages->next) |
| 257 | return NULL; |
| 258 | ftrace_pages = ftrace_pages->next; |
| 259 | } |
| 260 | |
| 261 | return &ftrace_pages->records[ftrace_pages->index++]; |
| 262 | } |
| 263 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 264 | static void |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 265 | ftrace_record_ip(unsigned long ip) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 266 | { |
| 267 | struct dyn_ftrace *node; |
| 268 | unsigned long flags; |
| 269 | unsigned long key; |
| 270 | int resched; |
| 271 | int atomic; |
Steven Rostedt | 2bb6f8d | 2008-05-12 21:21:02 +0200 | [diff] [blame] | 272 | int cpu; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 273 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 274 | if (!ftrace_enabled || ftrace_disabled) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 275 | return; |
| 276 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 277 | resched = need_resched(); |
| 278 | preempt_disable_notrace(); |
| 279 | |
Steven Rostedt | 2bb6f8d | 2008-05-12 21:21:02 +0200 | [diff] [blame] | 280 | /* |
| 281 | * We simply need to protect against recursion. |
| 282 | * Use the the raw version of smp_processor_id and not |
| 283 | * __get_cpu_var which can call debug hooks that can |
| 284 | * cause a recursive crash here. |
| 285 | */ |
| 286 | cpu = raw_smp_processor_id(); |
| 287 | per_cpu(ftrace_shutdown_disable_cpu, cpu)++; |
| 288 | if (per_cpu(ftrace_shutdown_disable_cpu, cpu) != 1) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 289 | goto out; |
| 290 | |
| 291 | if (unlikely(ftrace_record_suspend)) |
| 292 | goto out; |
| 293 | |
| 294 | key = hash_long(ip, FTRACE_HASHBITS); |
| 295 | |
| 296 | WARN_ON_ONCE(key >= FTRACE_HASHSIZE); |
| 297 | |
| 298 | if (ftrace_ip_in_hash(ip, key)) |
| 299 | goto out; |
| 300 | |
| 301 | atomic = irqs_disabled(); |
| 302 | |
| 303 | spin_lock_irqsave(&ftrace_shutdown_lock, flags); |
| 304 | |
| 305 | /* This ip may have hit the hash before the lock */ |
| 306 | if (ftrace_ip_in_hash(ip, key)) |
| 307 | goto out_unlock; |
| 308 | |
| 309 | /* |
| 310 | * There's a slight race that the ftraced will update the |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 311 | * hash and reset here. If it is already converted, skip it. |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 312 | */ |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 313 | if (ftrace_ip_converted(ip)) |
| 314 | goto out_unlock; |
| 315 | |
| 316 | node = ftrace_alloc_dyn_node(ip); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 317 | if (!node) |
| 318 | goto out_unlock; |
| 319 | |
| 320 | node->ip = ip; |
| 321 | |
| 322 | ftrace_add_hash(node, key); |
| 323 | |
| 324 | ftraced_trigger = 1; |
| 325 | |
| 326 | out_unlock: |
| 327 | spin_unlock_irqrestore(&ftrace_shutdown_lock, flags); |
| 328 | out: |
Steven Rostedt | 2bb6f8d | 2008-05-12 21:21:02 +0200 | [diff] [blame] | 329 | per_cpu(ftrace_shutdown_disable_cpu, cpu)--; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 330 | |
| 331 | /* prevent recursion with scheduler */ |
| 332 | if (resched) |
| 333 | preempt_enable_no_resched_notrace(); |
| 334 | else |
| 335 | preempt_enable_notrace(); |
| 336 | } |
| 337 | |
Steven Rostedt | caf8cde | 2008-05-12 21:20:50 +0200 | [diff] [blame] | 338 | #define FTRACE_ADDR ((long)(ftrace_caller)) |
| 339 | #define MCOUNT_ADDR ((long)(mcount)) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 340 | |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 341 | static int |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 342 | __ftrace_replace_code(struct dyn_ftrace *rec, |
| 343 | unsigned char *old, unsigned char *new, int enable) |
| 344 | { |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 345 | unsigned long ip, fl; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 346 | |
| 347 | ip = rec->ip; |
| 348 | |
| 349 | if (ftrace_filtered && enable) { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 350 | /* |
| 351 | * If filtering is on: |
| 352 | * |
| 353 | * If this record is set to be filtered and |
| 354 | * is enabled then do nothing. |
| 355 | * |
| 356 | * If this record is set to be filtered and |
| 357 | * it is not enabled, enable it. |
| 358 | * |
| 359 | * If this record is not set to be filtered |
| 360 | * and it is not enabled do nothing. |
| 361 | * |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 362 | * If this record is set not to trace then |
| 363 | * do nothing. |
| 364 | * |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 365 | * If this record is not set to be filtered and |
| 366 | * it is enabled, disable it. |
| 367 | */ |
| 368 | fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED); |
| 369 | |
| 370 | if ((fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) || |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 371 | (fl == 0) || (rec->flags & FTRACE_FL_NOTRACE)) |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 372 | return 0; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 373 | |
| 374 | /* |
| 375 | * If it is enabled disable it, |
| 376 | * otherwise enable it! |
| 377 | */ |
| 378 | if (fl == FTRACE_FL_ENABLED) { |
| 379 | /* swap new and old */ |
| 380 | new = old; |
| 381 | old = ftrace_call_replace(ip, FTRACE_ADDR); |
| 382 | rec->flags &= ~FTRACE_FL_ENABLED; |
| 383 | } else { |
| 384 | new = ftrace_call_replace(ip, FTRACE_ADDR); |
| 385 | rec->flags |= FTRACE_FL_ENABLED; |
| 386 | } |
| 387 | } else { |
| 388 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 389 | if (enable) { |
| 390 | /* |
| 391 | * If this record is set not to trace and is |
| 392 | * not enabled, do nothing. |
| 393 | */ |
| 394 | fl = rec->flags & (FTRACE_FL_NOTRACE | FTRACE_FL_ENABLED); |
| 395 | if (fl == FTRACE_FL_NOTRACE) |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 396 | return 0; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 397 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 398 | new = ftrace_call_replace(ip, FTRACE_ADDR); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 399 | } else |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 400 | old = ftrace_call_replace(ip, FTRACE_ADDR); |
| 401 | |
| 402 | if (enable) { |
| 403 | if (rec->flags & FTRACE_FL_ENABLED) |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 404 | return 0; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 405 | rec->flags |= FTRACE_FL_ENABLED; |
| 406 | } else { |
| 407 | if (!(rec->flags & FTRACE_FL_ENABLED)) |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 408 | return 0; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 409 | rec->flags &= ~FTRACE_FL_ENABLED; |
| 410 | } |
| 411 | } |
| 412 | |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 413 | return ftrace_modify_code(ip, old, new); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 414 | } |
| 415 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 416 | static void ftrace_replace_code(int enable) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 417 | { |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 418 | int i, failed; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 419 | unsigned char *new = NULL, *old = NULL; |
| 420 | struct dyn_ftrace *rec; |
| 421 | struct ftrace_page *pg; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 422 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 423 | if (enable) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 424 | old = ftrace_nop_replace(); |
| 425 | else |
| 426 | new = ftrace_nop_replace(); |
| 427 | |
| 428 | for (pg = ftrace_pages_start; pg; pg = pg->next) { |
| 429 | for (i = 0; i < pg->index; i++) { |
| 430 | rec = &pg->records[i]; |
| 431 | |
| 432 | /* don't modify code that has already faulted */ |
| 433 | if (rec->flags & FTRACE_FL_FAILED) |
| 434 | continue; |
| 435 | |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 436 | failed = __ftrace_replace_code(rec, old, new, enable); |
| 437 | if (failed && (rec->flags & FTRACE_FL_CONVERTED)) { |
| 438 | rec->flags |= FTRACE_FL_FAILED; |
| 439 | if ((system_state == SYSTEM_BOOTING) || |
| 440 | !kernel_text_address(rec->ip)) { |
| 441 | ftrace_del_hash(rec); |
| 442 | ftrace_free_rec(rec); |
| 443 | } |
| 444 | } |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 445 | } |
| 446 | } |
| 447 | } |
| 448 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 449 | static void ftrace_shutdown_replenish(void) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 450 | { |
| 451 | if (ftrace_pages->next) |
| 452 | return; |
| 453 | |
| 454 | /* allocate another page */ |
| 455 | ftrace_pages->next = (void *)get_zeroed_page(GFP_KERNEL); |
| 456 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 457 | |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 458 | static int |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 459 | ftrace_code_disable(struct dyn_ftrace *rec) |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 460 | { |
| 461 | unsigned long ip; |
| 462 | unsigned char *nop, *call; |
| 463 | int failed; |
| 464 | |
| 465 | ip = rec->ip; |
| 466 | |
| 467 | nop = ftrace_nop_replace(); |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 468 | call = ftrace_call_replace(ip, MCOUNT_ADDR); |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 469 | |
| 470 | failed = ftrace_modify_code(ip, call, nop); |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 471 | if (failed) { |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 472 | rec->flags |= FTRACE_FL_FAILED; |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 473 | return 0; |
Steven Rostedt | 37ad508 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 474 | } |
Abhishek Sagar | 492a7ea5 | 2008-05-25 00:10:04 +0530 | [diff] [blame] | 475 | return 1; |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 476 | } |
| 477 | |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 478 | static int __ftrace_update_code(void *ignore); |
| 479 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 480 | static int __ftrace_modify_code(void *data) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 481 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 482 | unsigned long addr; |
| 483 | int *command = data; |
| 484 | |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 485 | if (*command & FTRACE_ENABLE_CALLS) { |
| 486 | /* |
| 487 | * Update any recorded ips now that we have the |
| 488 | * machine stopped |
| 489 | */ |
| 490 | __ftrace_update_code(NULL); |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 491 | ftrace_replace_code(1); |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 492 | } else if (*command & FTRACE_DISABLE_CALLS) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 493 | ftrace_replace_code(0); |
| 494 | |
| 495 | if (*command & FTRACE_UPDATE_TRACE_FUNC) |
| 496 | ftrace_update_ftrace_func(ftrace_trace_function); |
| 497 | |
| 498 | if (*command & FTRACE_ENABLE_MCOUNT) { |
| 499 | addr = (unsigned long)ftrace_record_ip; |
| 500 | ftrace_mcount_set(&addr); |
| 501 | } else if (*command & FTRACE_DISABLE_MCOUNT) { |
| 502 | addr = (unsigned long)ftrace_stub; |
| 503 | ftrace_mcount_set(&addr); |
| 504 | } |
| 505 | |
| 506 | return 0; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 507 | } |
| 508 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 509 | static void ftrace_run_update_code(int command) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 510 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 511 | stop_machine_run(__ftrace_modify_code, &command, NR_CPUS); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 512 | } |
| 513 | |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 514 | void ftrace_disable_daemon(void) |
| 515 | { |
| 516 | /* Stop the daemon from calling kstop_machine */ |
| 517 | mutex_lock(&ftraced_lock); |
| 518 | ftraced_stop = 1; |
| 519 | mutex_unlock(&ftraced_lock); |
| 520 | |
| 521 | ftrace_force_update(); |
| 522 | } |
| 523 | |
| 524 | void ftrace_enable_daemon(void) |
| 525 | { |
| 526 | mutex_lock(&ftraced_lock); |
| 527 | ftraced_stop = 0; |
| 528 | mutex_unlock(&ftraced_lock); |
| 529 | |
| 530 | ftrace_force_update(); |
| 531 | } |
| 532 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 533 | static ftrace_func_t saved_ftrace_func; |
| 534 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 535 | static void ftrace_startup(void) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 536 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 537 | int command = 0; |
| 538 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 539 | if (unlikely(ftrace_disabled)) |
| 540 | return; |
| 541 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 542 | mutex_lock(&ftraced_lock); |
| 543 | ftraced_suspend++; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 544 | if (ftraced_suspend == 1) |
| 545 | command |= FTRACE_ENABLE_CALLS; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 546 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 547 | if (saved_ftrace_func != ftrace_trace_function) { |
| 548 | saved_ftrace_func = ftrace_trace_function; |
| 549 | command |= FTRACE_UPDATE_TRACE_FUNC; |
| 550 | } |
| 551 | |
| 552 | if (!command || !ftrace_enabled) |
| 553 | goto out; |
| 554 | |
| 555 | ftrace_run_update_code(command); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 556 | out: |
| 557 | mutex_unlock(&ftraced_lock); |
| 558 | } |
| 559 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 560 | static void ftrace_shutdown(void) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 561 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 562 | int command = 0; |
| 563 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 564 | if (unlikely(ftrace_disabled)) |
| 565 | return; |
| 566 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 567 | mutex_lock(&ftraced_lock); |
| 568 | ftraced_suspend--; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 569 | if (!ftraced_suspend) |
| 570 | command |= FTRACE_DISABLE_CALLS; |
| 571 | |
| 572 | if (saved_ftrace_func != ftrace_trace_function) { |
| 573 | saved_ftrace_func = ftrace_trace_function; |
| 574 | command |= FTRACE_UPDATE_TRACE_FUNC; |
| 575 | } |
| 576 | |
| 577 | if (!command || !ftrace_enabled) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 578 | goto out; |
| 579 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 580 | ftrace_run_update_code(command); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 581 | out: |
| 582 | mutex_unlock(&ftraced_lock); |
| 583 | } |
| 584 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 585 | static void ftrace_startup_sysctl(void) |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 586 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 587 | int command = FTRACE_ENABLE_MCOUNT; |
| 588 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 589 | if (unlikely(ftrace_disabled)) |
| 590 | return; |
| 591 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 592 | mutex_lock(&ftraced_lock); |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 593 | /* Force update next time */ |
| 594 | saved_ftrace_func = NULL; |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 595 | /* ftraced_suspend is true if we want ftrace running */ |
| 596 | if (ftraced_suspend) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 597 | command |= FTRACE_ENABLE_CALLS; |
| 598 | |
| 599 | ftrace_run_update_code(command); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 600 | mutex_unlock(&ftraced_lock); |
| 601 | } |
| 602 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 603 | static void ftrace_shutdown_sysctl(void) |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 604 | { |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 605 | int command = FTRACE_DISABLE_MCOUNT; |
| 606 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 607 | if (unlikely(ftrace_disabled)) |
| 608 | return; |
| 609 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 610 | mutex_lock(&ftraced_lock); |
| 611 | /* ftraced_suspend is true if ftrace is running */ |
| 612 | if (ftraced_suspend) |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 613 | command |= FTRACE_DISABLE_CALLS; |
| 614 | |
| 615 | ftrace_run_update_code(command); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 616 | mutex_unlock(&ftraced_lock); |
| 617 | } |
| 618 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 619 | static cycle_t ftrace_update_time; |
| 620 | static unsigned long ftrace_update_cnt; |
| 621 | unsigned long ftrace_update_tot_cnt; |
| 622 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 623 | static int __ftrace_update_code(void *ignore) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 624 | { |
| 625 | struct dyn_ftrace *p; |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 626 | struct hlist_node *t, *n; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 627 | int save_ftrace_enabled; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 628 | cycle_t start, stop; |
| 629 | int i; |
| 630 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 631 | /* Don't be recording funcs now */ |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 632 | ftrace_record_suspend++; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 633 | save_ftrace_enabled = ftrace_enabled; |
| 634 | ftrace_enabled = 0; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 635 | |
Ingo Molnar | 750ed1a | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 636 | start = ftrace_now(raw_smp_processor_id()); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 637 | ftrace_update_cnt = 0; |
| 638 | |
| 639 | /* No locks needed, the machine is stopped! */ |
| 640 | for (i = 0; i < FTRACE_HASHSIZE; i++) { |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 641 | /* all CPUS are stopped, we are safe to modify code */ |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 642 | hlist_for_each_entry_safe(p, t, n, &ftrace_hash[i], node) { |
| 643 | /* Skip over failed records which have not been |
| 644 | * freed. */ |
| 645 | if (p->flags & FTRACE_FL_FAILED) |
| 646 | continue; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 647 | |
Abhishek Sagar | 0eb9670 | 2008-06-01 21:47:30 +0530 | [diff] [blame^] | 648 | /* Unconverted records are always at the head of the |
| 649 | * hash bucket. Once we encounter a converted record, |
| 650 | * simply skip over to the next bucket. Saves ftraced |
| 651 | * some processor cycles (ftrace does its bid for |
| 652 | * global warming :-p ). */ |
| 653 | if (p->flags & (FTRACE_FL_CONVERTED)) |
| 654 | break; |
| 655 | |
| 656 | if (ftrace_code_disable(p)) { |
| 657 | p->flags |= FTRACE_FL_CONVERTED; |
| 658 | ftrace_update_cnt++; |
| 659 | } else { |
| 660 | if ((system_state == SYSTEM_BOOTING) || |
| 661 | !kernel_text_address(p->ip)) { |
| 662 | ftrace_del_hash(p); |
| 663 | ftrace_free_rec(p); |
| 664 | |
| 665 | } |
| 666 | } |
| 667 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 668 | } |
| 669 | |
Ingo Molnar | 750ed1a | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 670 | stop = ftrace_now(raw_smp_processor_id()); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 671 | ftrace_update_time = stop - start; |
| 672 | ftrace_update_tot_cnt += ftrace_update_cnt; |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 673 | ftraced_trigger = 0; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 674 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 675 | ftrace_enabled = save_ftrace_enabled; |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 676 | ftrace_record_suspend--; |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 677 | |
| 678 | return 0; |
| 679 | } |
| 680 | |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 681 | static int ftrace_update_code(void) |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 682 | { |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 683 | if (unlikely(ftrace_disabled) || |
| 684 | !ftrace_enabled || !ftraced_trigger) |
| 685 | return 0; |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 686 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 687 | stop_machine_run(__ftrace_update_code, NULL, NR_CPUS); |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 688 | |
| 689 | return 1; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 690 | } |
| 691 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 692 | static int ftraced(void *ignore) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 693 | { |
| 694 | unsigned long usecs; |
| 695 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 696 | while (!kthread_should_stop()) { |
| 697 | |
Steven Rostedt | 07a267c | 2008-05-12 21:20:55 +0200 | [diff] [blame] | 698 | set_current_state(TASK_INTERRUPTIBLE); |
| 699 | |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 700 | /* check once a second */ |
| 701 | schedule_timeout(HZ); |
| 702 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 703 | if (unlikely(ftrace_disabled)) |
| 704 | continue; |
| 705 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 706 | mutex_lock(&ftrace_sysctl_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 707 | mutex_lock(&ftraced_lock); |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 708 | if (!ftraced_suspend && !ftraced_stop && |
| 709 | ftrace_update_code()) { |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 710 | usecs = nsecs_to_usecs(ftrace_update_time); |
| 711 | if (ftrace_update_tot_cnt > 100000) { |
| 712 | ftrace_update_tot_cnt = 0; |
| 713 | pr_info("hm, dftrace overflow: %lu change%s" |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 714 | " (%lu total) in %lu usec%s\n", |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 715 | ftrace_update_cnt, |
| 716 | ftrace_update_cnt != 1 ? "s" : "", |
| 717 | ftrace_update_tot_cnt, |
| 718 | usecs, usecs != 1 ? "s" : ""); |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 719 | ftrace_disabled = 1; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 720 | WARN_ON_ONCE(1); |
| 721 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 722 | } |
| 723 | mutex_unlock(&ftraced_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 724 | mutex_unlock(&ftrace_sysctl_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 725 | |
| 726 | ftrace_shutdown_replenish(); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 727 | } |
| 728 | __set_current_state(TASK_RUNNING); |
| 729 | return 0; |
| 730 | } |
| 731 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 732 | static int __init ftrace_dyn_table_alloc(void) |
| 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 | |
| 759 | cnt = NR_TO_INIT / ENTRIES_PER_PAGE; |
| 760 | |
| 761 | for (i = 0; i < cnt; i++) { |
| 762 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
| 763 | |
| 764 | /* If we fail, we'll try later anyway */ |
| 765 | if (!pg->next) |
| 766 | break; |
| 767 | |
| 768 | pg = pg->next; |
| 769 | } |
| 770 | |
| 771 | return 0; |
| 772 | } |
| 773 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 774 | enum { |
| 775 | FTRACE_ITER_FILTER = (1 << 0), |
| 776 | FTRACE_ITER_CONT = (1 << 1), |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 777 | FTRACE_ITER_NOTRACE = (1 << 2), |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 778 | }; |
| 779 | |
| 780 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
| 781 | |
| 782 | struct ftrace_iterator { |
| 783 | loff_t pos; |
| 784 | struct ftrace_page *pg; |
| 785 | unsigned idx; |
| 786 | unsigned flags; |
| 787 | unsigned char buffer[FTRACE_BUFF_MAX+1]; |
| 788 | unsigned buffer_idx; |
| 789 | unsigned filtered; |
| 790 | }; |
| 791 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 792 | static void * |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 793 | t_next(struct seq_file *m, void *v, loff_t *pos) |
| 794 | { |
| 795 | struct ftrace_iterator *iter = m->private; |
| 796 | struct dyn_ftrace *rec = NULL; |
| 797 | |
| 798 | (*pos)++; |
| 799 | |
| 800 | retry: |
| 801 | if (iter->idx >= iter->pg->index) { |
| 802 | if (iter->pg->next) { |
| 803 | iter->pg = iter->pg->next; |
| 804 | iter->idx = 0; |
| 805 | goto retry; |
| 806 | } |
| 807 | } else { |
| 808 | rec = &iter->pg->records[iter->idx++]; |
| 809 | if ((rec->flags & FTRACE_FL_FAILED) || |
| 810 | ((iter->flags & FTRACE_ITER_FILTER) && |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 811 | !(rec->flags & FTRACE_FL_FILTER)) || |
| 812 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
| 813 | !(rec->flags & FTRACE_FL_NOTRACE))) { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 814 | rec = NULL; |
| 815 | goto retry; |
| 816 | } |
| 817 | } |
| 818 | |
| 819 | iter->pos = *pos; |
| 820 | |
| 821 | return rec; |
| 822 | } |
| 823 | |
| 824 | static void *t_start(struct seq_file *m, loff_t *pos) |
| 825 | { |
| 826 | struct ftrace_iterator *iter = m->private; |
| 827 | void *p = NULL; |
| 828 | loff_t l = -1; |
| 829 | |
| 830 | if (*pos != iter->pos) { |
| 831 | for (p = t_next(m, p, &l); p && l < *pos; p = t_next(m, p, &l)) |
| 832 | ; |
| 833 | } else { |
| 834 | l = *pos; |
| 835 | p = t_next(m, p, &l); |
| 836 | } |
| 837 | |
| 838 | return p; |
| 839 | } |
| 840 | |
| 841 | static void t_stop(struct seq_file *m, void *p) |
| 842 | { |
| 843 | } |
| 844 | |
| 845 | static int t_show(struct seq_file *m, void *v) |
| 846 | { |
| 847 | struct dyn_ftrace *rec = v; |
| 848 | char str[KSYM_SYMBOL_LEN]; |
| 849 | |
| 850 | if (!rec) |
| 851 | return 0; |
| 852 | |
| 853 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
| 854 | |
| 855 | seq_printf(m, "%s\n", str); |
| 856 | |
| 857 | return 0; |
| 858 | } |
| 859 | |
| 860 | static struct seq_operations show_ftrace_seq_ops = { |
| 861 | .start = t_start, |
| 862 | .next = t_next, |
| 863 | .stop = t_stop, |
| 864 | .show = t_show, |
| 865 | }; |
| 866 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 867 | static int |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 868 | ftrace_avail_open(struct inode *inode, struct file *file) |
| 869 | { |
| 870 | struct ftrace_iterator *iter; |
| 871 | int ret; |
| 872 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 873 | if (unlikely(ftrace_disabled)) |
| 874 | return -ENODEV; |
| 875 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 876 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
| 877 | if (!iter) |
| 878 | return -ENOMEM; |
| 879 | |
| 880 | iter->pg = ftrace_pages_start; |
| 881 | iter->pos = -1; |
| 882 | |
| 883 | ret = seq_open(file, &show_ftrace_seq_ops); |
| 884 | if (!ret) { |
| 885 | struct seq_file *m = file->private_data; |
Ingo Molnar | 4bf39a9 | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 886 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 887 | m->private = iter; |
Ingo Molnar | 4bf39a9 | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 888 | } else { |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 889 | kfree(iter); |
Ingo Molnar | 4bf39a9 | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 890 | } |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 891 | |
| 892 | return ret; |
| 893 | } |
| 894 | |
| 895 | int ftrace_avail_release(struct inode *inode, struct file *file) |
| 896 | { |
| 897 | struct seq_file *m = (struct seq_file *)file->private_data; |
| 898 | struct ftrace_iterator *iter = m->private; |
| 899 | |
| 900 | seq_release(inode, file); |
| 901 | kfree(iter); |
Ingo Molnar | 4bf39a9 | 2008-05-12 21:20:46 +0200 | [diff] [blame] | 902 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 903 | return 0; |
| 904 | } |
| 905 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 906 | static void ftrace_filter_reset(int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 907 | { |
| 908 | struct ftrace_page *pg; |
| 909 | struct dyn_ftrace *rec; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 910 | unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 911 | unsigned i; |
| 912 | |
| 913 | /* keep kstop machine from running */ |
| 914 | preempt_disable(); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 915 | if (enable) |
| 916 | ftrace_filtered = 0; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 917 | pg = ftrace_pages_start; |
| 918 | while (pg) { |
| 919 | for (i = 0; i < pg->index; i++) { |
| 920 | rec = &pg->records[i]; |
| 921 | if (rec->flags & FTRACE_FL_FAILED) |
| 922 | continue; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 923 | rec->flags &= ~type; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 924 | } |
| 925 | pg = pg->next; |
| 926 | } |
| 927 | preempt_enable(); |
| 928 | } |
| 929 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 930 | static int |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 931 | ftrace_regex_open(struct inode *inode, struct file *file, int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 932 | { |
| 933 | struct ftrace_iterator *iter; |
| 934 | int ret = 0; |
| 935 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 936 | if (unlikely(ftrace_disabled)) |
| 937 | return -ENODEV; |
| 938 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 939 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
| 940 | if (!iter) |
| 941 | return -ENOMEM; |
| 942 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 943 | mutex_lock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 944 | if ((file->f_mode & FMODE_WRITE) && |
| 945 | !(file->f_flags & O_APPEND)) |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 946 | ftrace_filter_reset(enable); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 947 | |
| 948 | if (file->f_mode & FMODE_READ) { |
| 949 | iter->pg = ftrace_pages_start; |
| 950 | iter->pos = -1; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 951 | iter->flags = enable ? FTRACE_ITER_FILTER : |
| 952 | FTRACE_ITER_NOTRACE; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 953 | |
| 954 | ret = seq_open(file, &show_ftrace_seq_ops); |
| 955 | if (!ret) { |
| 956 | struct seq_file *m = file->private_data; |
| 957 | m->private = iter; |
| 958 | } else |
| 959 | kfree(iter); |
| 960 | } else |
| 961 | file->private_data = iter; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 962 | mutex_unlock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 963 | |
| 964 | return ret; |
| 965 | } |
| 966 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 967 | static int |
| 968 | ftrace_filter_open(struct inode *inode, struct file *file) |
| 969 | { |
| 970 | return ftrace_regex_open(inode, file, 1); |
| 971 | } |
| 972 | |
| 973 | static int |
| 974 | ftrace_notrace_open(struct inode *inode, struct file *file) |
| 975 | { |
| 976 | return ftrace_regex_open(inode, file, 0); |
| 977 | } |
| 978 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 979 | static ssize_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 980 | ftrace_regex_read(struct file *file, char __user *ubuf, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 981 | size_t cnt, loff_t *ppos) |
| 982 | { |
| 983 | if (file->f_mode & FMODE_READ) |
| 984 | return seq_read(file, ubuf, cnt, ppos); |
| 985 | else |
| 986 | return -EPERM; |
| 987 | } |
| 988 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 989 | static loff_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 990 | ftrace_regex_lseek(struct file *file, loff_t offset, int origin) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 991 | { |
| 992 | loff_t ret; |
| 993 | |
| 994 | if (file->f_mode & FMODE_READ) |
| 995 | ret = seq_lseek(file, offset, origin); |
| 996 | else |
| 997 | file->f_pos = ret = 1; |
| 998 | |
| 999 | return ret; |
| 1000 | } |
| 1001 | |
| 1002 | enum { |
| 1003 | MATCH_FULL, |
| 1004 | MATCH_FRONT_ONLY, |
| 1005 | MATCH_MIDDLE_ONLY, |
| 1006 | MATCH_END_ONLY, |
| 1007 | }; |
| 1008 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1009 | static void |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1010 | ftrace_match(unsigned char *buff, int len, int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1011 | { |
| 1012 | char str[KSYM_SYMBOL_LEN]; |
| 1013 | char *search = NULL; |
| 1014 | struct ftrace_page *pg; |
| 1015 | struct dyn_ftrace *rec; |
| 1016 | int type = MATCH_FULL; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1017 | unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1018 | unsigned i, match = 0, search_len = 0; |
| 1019 | |
| 1020 | for (i = 0; i < len; i++) { |
| 1021 | if (buff[i] == '*') { |
| 1022 | if (!i) { |
| 1023 | search = buff + i + 1; |
| 1024 | type = MATCH_END_ONLY; |
| 1025 | search_len = len - (i + 1); |
| 1026 | } else { |
| 1027 | if (type == MATCH_END_ONLY) { |
| 1028 | type = MATCH_MIDDLE_ONLY; |
| 1029 | } else { |
| 1030 | match = i; |
| 1031 | type = MATCH_FRONT_ONLY; |
| 1032 | } |
| 1033 | buff[i] = 0; |
| 1034 | break; |
| 1035 | } |
| 1036 | } |
| 1037 | } |
| 1038 | |
| 1039 | /* keep kstop machine from running */ |
| 1040 | preempt_disable(); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1041 | if (enable) |
| 1042 | ftrace_filtered = 1; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1043 | pg = ftrace_pages_start; |
| 1044 | while (pg) { |
| 1045 | for (i = 0; i < pg->index; i++) { |
| 1046 | int matched = 0; |
| 1047 | char *ptr; |
| 1048 | |
| 1049 | rec = &pg->records[i]; |
| 1050 | if (rec->flags & FTRACE_FL_FAILED) |
| 1051 | continue; |
| 1052 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
| 1053 | switch (type) { |
| 1054 | case MATCH_FULL: |
| 1055 | if (strcmp(str, buff) == 0) |
| 1056 | matched = 1; |
| 1057 | break; |
| 1058 | case MATCH_FRONT_ONLY: |
| 1059 | if (memcmp(str, buff, match) == 0) |
| 1060 | matched = 1; |
| 1061 | break; |
| 1062 | case MATCH_MIDDLE_ONLY: |
| 1063 | if (strstr(str, search)) |
| 1064 | matched = 1; |
| 1065 | break; |
| 1066 | case MATCH_END_ONLY: |
| 1067 | ptr = strstr(str, search); |
| 1068 | if (ptr && (ptr[search_len] == 0)) |
| 1069 | matched = 1; |
| 1070 | break; |
| 1071 | } |
| 1072 | if (matched) |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1073 | rec->flags |= flag; |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1074 | } |
| 1075 | pg = pg->next; |
| 1076 | } |
| 1077 | preempt_enable(); |
| 1078 | } |
| 1079 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1080 | static ssize_t |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1081 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
| 1082 | size_t cnt, loff_t *ppos, int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1083 | { |
| 1084 | struct ftrace_iterator *iter; |
| 1085 | char ch; |
| 1086 | size_t read = 0; |
| 1087 | ssize_t ret; |
| 1088 | |
| 1089 | if (!cnt || cnt < 0) |
| 1090 | return 0; |
| 1091 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1092 | mutex_lock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1093 | |
| 1094 | if (file->f_mode & FMODE_READ) { |
| 1095 | struct seq_file *m = file->private_data; |
| 1096 | iter = m->private; |
| 1097 | } else |
| 1098 | iter = file->private_data; |
| 1099 | |
| 1100 | if (!*ppos) { |
| 1101 | iter->flags &= ~FTRACE_ITER_CONT; |
| 1102 | iter->buffer_idx = 0; |
| 1103 | } |
| 1104 | |
| 1105 | ret = get_user(ch, ubuf++); |
| 1106 | if (ret) |
| 1107 | goto out; |
| 1108 | read++; |
| 1109 | cnt--; |
| 1110 | |
| 1111 | if (!(iter->flags & ~FTRACE_ITER_CONT)) { |
| 1112 | /* skip white space */ |
| 1113 | while (cnt && isspace(ch)) { |
| 1114 | ret = get_user(ch, ubuf++); |
| 1115 | if (ret) |
| 1116 | goto out; |
| 1117 | read++; |
| 1118 | cnt--; |
| 1119 | } |
| 1120 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1121 | if (isspace(ch)) { |
| 1122 | file->f_pos += read; |
| 1123 | ret = read; |
| 1124 | goto out; |
| 1125 | } |
| 1126 | |
| 1127 | iter->buffer_idx = 0; |
| 1128 | } |
| 1129 | |
| 1130 | while (cnt && !isspace(ch)) { |
| 1131 | if (iter->buffer_idx < FTRACE_BUFF_MAX) |
| 1132 | iter->buffer[iter->buffer_idx++] = ch; |
| 1133 | else { |
| 1134 | ret = -EINVAL; |
| 1135 | goto out; |
| 1136 | } |
| 1137 | ret = get_user(ch, ubuf++); |
| 1138 | if (ret) |
| 1139 | goto out; |
| 1140 | read++; |
| 1141 | cnt--; |
| 1142 | } |
| 1143 | |
| 1144 | if (isspace(ch)) { |
| 1145 | iter->filtered++; |
| 1146 | iter->buffer[iter->buffer_idx] = 0; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1147 | ftrace_match(iter->buffer, iter->buffer_idx, enable); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1148 | iter->buffer_idx = 0; |
| 1149 | } else |
| 1150 | iter->flags |= FTRACE_ITER_CONT; |
| 1151 | |
| 1152 | |
| 1153 | file->f_pos += read; |
| 1154 | |
| 1155 | ret = read; |
| 1156 | out: |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1157 | mutex_unlock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1158 | |
| 1159 | return ret; |
| 1160 | } |
| 1161 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1162 | static ssize_t |
| 1163 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
| 1164 | size_t cnt, loff_t *ppos) |
| 1165 | { |
| 1166 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); |
| 1167 | } |
| 1168 | |
| 1169 | static ssize_t |
| 1170 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
| 1171 | size_t cnt, loff_t *ppos) |
| 1172 | { |
| 1173 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); |
| 1174 | } |
| 1175 | |
| 1176 | static void |
| 1177 | ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) |
| 1178 | { |
| 1179 | if (unlikely(ftrace_disabled)) |
| 1180 | return; |
| 1181 | |
| 1182 | mutex_lock(&ftrace_regex_lock); |
| 1183 | if (reset) |
| 1184 | ftrace_filter_reset(enable); |
| 1185 | if (buf) |
| 1186 | ftrace_match(buf, len, enable); |
| 1187 | mutex_unlock(&ftrace_regex_lock); |
| 1188 | } |
| 1189 | |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 1190 | /** |
| 1191 | * ftrace_set_filter - set a function to filter on in ftrace |
| 1192 | * @buf - the string that holds the function filter text. |
| 1193 | * @len - the length of the string. |
| 1194 | * @reset - non zero to reset all filters before applying this filter. |
| 1195 | * |
| 1196 | * Filters denote which functions should be enabled when tracing is enabled. |
| 1197 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. |
| 1198 | */ |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1199 | void ftrace_set_filter(unsigned char *buf, int len, int reset) |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 1200 | { |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1201 | ftrace_set_regex(buf, len, reset, 1); |
| 1202 | } |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1203 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1204 | /** |
| 1205 | * ftrace_set_notrace - set a function to not trace in ftrace |
| 1206 | * @buf - the string that holds the function notrace text. |
| 1207 | * @len - the length of the string. |
| 1208 | * @reset - non zero to reset all filters before applying this filter. |
| 1209 | * |
| 1210 | * Notrace Filters denote which functions should not be enabled when tracing |
| 1211 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled |
| 1212 | * for tracing. |
| 1213 | */ |
| 1214 | void ftrace_set_notrace(unsigned char *buf, int len, int reset) |
| 1215 | { |
| 1216 | ftrace_set_regex(buf, len, reset, 0); |
Steven Rostedt | 77a2b37 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 1217 | } |
| 1218 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1219 | static int |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1220 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1221 | { |
| 1222 | struct seq_file *m = (struct seq_file *)file->private_data; |
| 1223 | struct ftrace_iterator *iter; |
| 1224 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1225 | mutex_lock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1226 | if (file->f_mode & FMODE_READ) { |
| 1227 | iter = m->private; |
| 1228 | |
| 1229 | seq_release(inode, file); |
| 1230 | } else |
| 1231 | iter = file->private_data; |
| 1232 | |
| 1233 | if (iter->buffer_idx) { |
| 1234 | iter->filtered++; |
| 1235 | iter->buffer[iter->buffer_idx] = 0; |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1236 | ftrace_match(iter->buffer, iter->buffer_idx, enable); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1237 | } |
| 1238 | |
| 1239 | mutex_lock(&ftrace_sysctl_lock); |
| 1240 | mutex_lock(&ftraced_lock); |
| 1241 | if (iter->filtered && ftraced_suspend && ftrace_enabled) |
| 1242 | ftrace_run_update_code(FTRACE_ENABLE_CALLS); |
| 1243 | mutex_unlock(&ftraced_lock); |
| 1244 | mutex_unlock(&ftrace_sysctl_lock); |
| 1245 | |
| 1246 | kfree(iter); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1247 | mutex_unlock(&ftrace_regex_lock); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1248 | return 0; |
| 1249 | } |
| 1250 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1251 | static int |
| 1252 | ftrace_filter_release(struct inode *inode, struct file *file) |
| 1253 | { |
| 1254 | return ftrace_regex_release(inode, file, 1); |
| 1255 | } |
| 1256 | |
| 1257 | static int |
| 1258 | ftrace_notrace_release(struct inode *inode, struct file *file) |
| 1259 | { |
| 1260 | return ftrace_regex_release(inode, file, 0); |
| 1261 | } |
| 1262 | |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 1263 | static ssize_t |
| 1264 | ftraced_read(struct file *filp, char __user *ubuf, |
| 1265 | size_t cnt, loff_t *ppos) |
| 1266 | { |
| 1267 | /* don't worry about races */ |
| 1268 | char *buf = ftraced_stop ? "disabled\n" : "enabled\n"; |
| 1269 | int r = strlen(buf); |
| 1270 | |
| 1271 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
| 1272 | } |
| 1273 | |
| 1274 | static ssize_t |
| 1275 | ftraced_write(struct file *filp, const char __user *ubuf, |
| 1276 | size_t cnt, loff_t *ppos) |
| 1277 | { |
| 1278 | char buf[64]; |
| 1279 | long val; |
| 1280 | int ret; |
| 1281 | |
| 1282 | if (cnt >= sizeof(buf)) |
| 1283 | return -EINVAL; |
| 1284 | |
| 1285 | if (copy_from_user(&buf, ubuf, cnt)) |
| 1286 | return -EFAULT; |
| 1287 | |
| 1288 | if (strncmp(buf, "enable", 6) == 0) |
| 1289 | val = 1; |
| 1290 | else if (strncmp(buf, "disable", 7) == 0) |
| 1291 | val = 0; |
| 1292 | else { |
| 1293 | buf[cnt] = 0; |
| 1294 | |
| 1295 | ret = strict_strtoul(buf, 10, &val); |
| 1296 | if (ret < 0) |
| 1297 | return ret; |
| 1298 | |
| 1299 | val = !!val; |
| 1300 | } |
| 1301 | |
| 1302 | if (val) |
| 1303 | ftrace_enable_daemon(); |
| 1304 | else |
| 1305 | ftrace_disable_daemon(); |
| 1306 | |
| 1307 | filp->f_pos += cnt; |
| 1308 | |
| 1309 | return cnt; |
| 1310 | } |
| 1311 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1312 | static struct file_operations ftrace_avail_fops = { |
| 1313 | .open = ftrace_avail_open, |
| 1314 | .read = seq_read, |
| 1315 | .llseek = seq_lseek, |
| 1316 | .release = ftrace_avail_release, |
| 1317 | }; |
| 1318 | |
| 1319 | static struct file_operations ftrace_filter_fops = { |
| 1320 | .open = ftrace_filter_open, |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1321 | .read = ftrace_regex_read, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1322 | .write = ftrace_filter_write, |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1323 | .llseek = ftrace_regex_lseek, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1324 | .release = ftrace_filter_release, |
| 1325 | }; |
| 1326 | |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1327 | static struct file_operations ftrace_notrace_fops = { |
| 1328 | .open = ftrace_notrace_open, |
| 1329 | .read = ftrace_regex_read, |
| 1330 | .write = ftrace_notrace_write, |
| 1331 | .llseek = ftrace_regex_lseek, |
| 1332 | .release = ftrace_notrace_release, |
| 1333 | }; |
| 1334 | |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 1335 | static struct file_operations ftraced_fops = { |
| 1336 | .open = tracing_open_generic, |
| 1337 | .read = ftraced_read, |
| 1338 | .write = ftraced_write, |
| 1339 | }; |
| 1340 | |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1341 | /** |
| 1342 | * ftrace_force_update - force an update to all recording ftrace functions |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1343 | */ |
| 1344 | int ftrace_force_update(void) |
| 1345 | { |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1346 | int ret = 0; |
| 1347 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1348 | if (unlikely(ftrace_disabled)) |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1349 | return -ENODEV; |
| 1350 | |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 1351 | mutex_lock(&ftrace_sysctl_lock); |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1352 | mutex_lock(&ftraced_lock); |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1353 | |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 1354 | /* |
| 1355 | * If ftraced_trigger is not set, then there is nothing |
| 1356 | * to update. |
| 1357 | */ |
| 1358 | if (ftraced_trigger && !ftrace_update_code()) |
| 1359 | ret = -EBUSY; |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1360 | |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1361 | mutex_unlock(&ftraced_lock); |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 1362 | mutex_unlock(&ftrace_sysctl_lock); |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1363 | |
| 1364 | return ret; |
| 1365 | } |
| 1366 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1367 | static void ftrace_force_shutdown(void) |
| 1368 | { |
| 1369 | struct task_struct *task; |
| 1370 | int command = FTRACE_DISABLE_CALLS | FTRACE_UPDATE_TRACE_FUNC; |
| 1371 | |
| 1372 | mutex_lock(&ftraced_lock); |
| 1373 | task = ftraced_task; |
| 1374 | ftraced_task = NULL; |
| 1375 | ftraced_suspend = -1; |
| 1376 | ftrace_run_update_code(command); |
| 1377 | mutex_unlock(&ftraced_lock); |
| 1378 | |
| 1379 | if (task) |
| 1380 | kthread_stop(task); |
| 1381 | } |
| 1382 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1383 | static __init int ftrace_init_debugfs(void) |
| 1384 | { |
| 1385 | struct dentry *d_tracer; |
| 1386 | struct dentry *entry; |
| 1387 | |
| 1388 | d_tracer = tracing_init_dentry(); |
| 1389 | |
| 1390 | entry = debugfs_create_file("available_filter_functions", 0444, |
| 1391 | d_tracer, NULL, &ftrace_avail_fops); |
| 1392 | if (!entry) |
| 1393 | pr_warning("Could not create debugfs " |
| 1394 | "'available_filter_functions' entry\n"); |
| 1395 | |
| 1396 | entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer, |
| 1397 | NULL, &ftrace_filter_fops); |
| 1398 | if (!entry) |
| 1399 | pr_warning("Could not create debugfs " |
| 1400 | "'set_ftrace_filter' entry\n"); |
Steven Rostedt | 41c52c0 | 2008-05-22 11:46:33 -0400 | [diff] [blame] | 1401 | |
| 1402 | entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer, |
| 1403 | NULL, &ftrace_notrace_fops); |
| 1404 | if (!entry) |
| 1405 | pr_warning("Could not create debugfs " |
| 1406 | "'set_ftrace_notrace' entry\n"); |
Steven Rostedt | ad90c0e | 2008-05-27 20:48:37 -0400 | [diff] [blame] | 1407 | |
| 1408 | entry = debugfs_create_file("ftraced_enabled", 0644, d_tracer, |
| 1409 | NULL, &ftraced_fops); |
| 1410 | if (!entry) |
| 1411 | pr_warning("Could not create debugfs " |
| 1412 | "'ftraced_enabled' entry\n"); |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1413 | return 0; |
| 1414 | } |
| 1415 | |
| 1416 | fs_initcall(ftrace_init_debugfs); |
| 1417 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1418 | static int __init ftrace_dynamic_init(void) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1419 | { |
| 1420 | struct task_struct *p; |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1421 | unsigned long addr; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1422 | int ret; |
| 1423 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1424 | addr = (unsigned long)ftrace_record_ip; |
Ingo Molnar | 9ff9cdb | 2008-05-12 21:20:50 +0200 | [diff] [blame] | 1425 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1426 | stop_machine_run(ftrace_dyn_arch_init, &addr, NR_CPUS); |
| 1427 | |
| 1428 | /* ftrace_dyn_arch_init places the return code in addr */ |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1429 | if (addr) { |
| 1430 | ret = (int)addr; |
| 1431 | goto failed; |
| 1432 | } |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1433 | |
Steven Rostedt | 3c1720f | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1434 | ret = ftrace_dyn_table_alloc(); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1435 | if (ret) |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1436 | goto failed; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1437 | |
| 1438 | p = kthread_run(ftraced, NULL, "ftraced"); |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1439 | if (IS_ERR(p)) { |
| 1440 | ret = -1; |
| 1441 | goto failed; |
| 1442 | } |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1443 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1444 | last_ftrace_enabled = ftrace_enabled = 1; |
Steven Rostedt | e1c08bd | 2008-05-12 21:20:44 +0200 | [diff] [blame] | 1445 | ftraced_task = p; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1446 | |
| 1447 | return 0; |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1448 | |
| 1449 | failed: |
| 1450 | ftrace_disabled = 1; |
| 1451 | return ret; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1452 | } |
| 1453 | |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1454 | core_initcall(ftrace_dynamic_init); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1455 | #else |
Ingo Molnar | c7aafc5 | 2008-05-12 21:20:45 +0200 | [diff] [blame] | 1456 | # define ftrace_startup() do { } while (0) |
| 1457 | # define ftrace_shutdown() do { } while (0) |
| 1458 | # define ftrace_startup_sysctl() do { } while (0) |
| 1459 | # define ftrace_shutdown_sysctl() do { } while (0) |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1460 | # define ftrace_force_shutdown() do { } while (0) |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1461 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
| 1462 | |
| 1463 | /** |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1464 | * ftrace_kill - totally shutdown ftrace |
| 1465 | * |
| 1466 | * This is a safety measure. If something was detected that seems |
| 1467 | * wrong, calling this function will keep ftrace from doing |
| 1468 | * any more modifications, and updates. |
| 1469 | * used when something went wrong. |
| 1470 | */ |
| 1471 | void ftrace_kill(void) |
| 1472 | { |
| 1473 | mutex_lock(&ftrace_sysctl_lock); |
| 1474 | ftrace_disabled = 1; |
| 1475 | ftrace_enabled = 0; |
| 1476 | |
| 1477 | clear_ftrace_function(); |
| 1478 | mutex_unlock(&ftrace_sysctl_lock); |
| 1479 | |
| 1480 | /* Try to totally disable ftrace */ |
| 1481 | ftrace_force_shutdown(); |
| 1482 | } |
| 1483 | |
| 1484 | /** |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1485 | * register_ftrace_function - register a function for profiling |
| 1486 | * @ops - ops structure that holds the function for profiling. |
| 1487 | * |
| 1488 | * Register a function to be called by all functions in the |
| 1489 | * kernel. |
| 1490 | * |
| 1491 | * Note: @ops->func and all the functions it calls must be labeled |
| 1492 | * with "notrace", otherwise it will go into a |
| 1493 | * recursive loop. |
| 1494 | */ |
| 1495 | int register_ftrace_function(struct ftrace_ops *ops) |
| 1496 | { |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1497 | int ret; |
| 1498 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1499 | if (unlikely(ftrace_disabled)) |
| 1500 | return -1; |
| 1501 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1502 | mutex_lock(&ftrace_sysctl_lock); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1503 | ret = __register_ftrace_function(ops); |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1504 | ftrace_startup(); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1505 | mutex_unlock(&ftrace_sysctl_lock); |
| 1506 | |
| 1507 | return ret; |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1508 | } |
| 1509 | |
| 1510 | /** |
| 1511 | * unregister_ftrace_function - unresgister a function for profiling. |
| 1512 | * @ops - ops structure that holds the function to unregister |
| 1513 | * |
| 1514 | * Unregister a function that was added to be called by ftrace profiling. |
| 1515 | */ |
| 1516 | int unregister_ftrace_function(struct ftrace_ops *ops) |
| 1517 | { |
| 1518 | int ret; |
| 1519 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1520 | mutex_lock(&ftrace_sysctl_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1521 | ret = __unregister_ftrace_function(ops); |
Steven Rostedt | d61f82d | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1522 | ftrace_shutdown(); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1523 | mutex_unlock(&ftrace_sysctl_lock); |
| 1524 | |
| 1525 | return ret; |
| 1526 | } |
| 1527 | |
Ingo Molnar | e309b41 | 2008-05-12 21:20:51 +0200 | [diff] [blame] | 1528 | int |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1529 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1530 | struct file *file, void __user *buffer, size_t *lenp, |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1531 | loff_t *ppos) |
| 1532 | { |
| 1533 | int ret; |
| 1534 | |
Steven Rostedt | 4eebcc8 | 2008-05-12 21:20:48 +0200 | [diff] [blame] | 1535 | if (unlikely(ftrace_disabled)) |
| 1536 | return -ENODEV; |
| 1537 | |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1538 | mutex_lock(&ftrace_sysctl_lock); |
| 1539 | |
Steven Rostedt | 5072c59 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1540 | ret = proc_dointvec(table, write, file, buffer, lenp, ppos); |
Steven Rostedt | b0fc494 | 2008-05-12 21:20:43 +0200 | [diff] [blame] | 1541 | |
| 1542 | if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) |
| 1543 | goto out; |
| 1544 | |
| 1545 | last_ftrace_enabled = ftrace_enabled; |
| 1546 | |
| 1547 | if (ftrace_enabled) { |
| 1548 | |
| 1549 | ftrace_startup_sysctl(); |
| 1550 | |
| 1551 | /* we are starting ftrace again */ |
| 1552 | if (ftrace_list != &ftrace_list_end) { |
| 1553 | if (ftrace_list->next == &ftrace_list_end) |
| 1554 | ftrace_trace_function = ftrace_list->func; |
| 1555 | else |
| 1556 | ftrace_trace_function = ftrace_list_func; |
| 1557 | } |
| 1558 | |
| 1559 | } else { |
| 1560 | /* stopping ftrace calls (just send to ftrace_stub) */ |
| 1561 | ftrace_trace_function = ftrace_stub; |
| 1562 | |
| 1563 | ftrace_shutdown_sysctl(); |
| 1564 | } |
| 1565 | |
| 1566 | out: |
| 1567 | mutex_unlock(&ftrace_sysctl_lock); |
Steven Rostedt | 3d08339 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1568 | return ret; |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1569 | } |