2 * Kprobes-based tracing events
4 * Created by Masami Hiramatsu <mhiramat@redhat.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 #include <linux/module.h>
21 #include <linux/uaccess.h>
22 #include <linux/kprobes.h>
23 #include <linux/seq_file.h>
24 #include <linux/slab.h>
25 #include <linux/smp.h>
26 #include <linux/debugfs.h>
27 #include <linux/types.h>
28 #include <linux/string.h>
29 #include <linux/ctype.h>
30 #include <linux/ptrace.h>
31 #include <linux/perf_event.h>
32 #include <linux/stringify.h>
33 #include <linux/limits.h>
34 #include <asm/bitsperlong.h>
37 #include "trace_output.h"
39 #define MAX_TRACE_ARGS 128
40 #define MAX_ARGSTR_LEN 63
41 #define MAX_EVENT_NAME_LEN 64
42 #define MAX_STRING_SIZE PATH_MAX
43 #define KPROBE_EVENT_SYSTEM "kprobes"
45 /* Reserved field names */
46 #define FIELD_STRING_IP "__probe_ip"
47 #define FIELD_STRING_RETIP "__probe_ret_ip"
48 #define FIELD_STRING_FUNC "__probe_func"
50 const char *reserved_field_names[] = {
53 "common_preempt_count",
62 /* Printing function type */
63 typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *,
65 #define PRINT_TYPE_FUNC_NAME(type) print_type_##type
66 #define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
68 /* Printing in basic type function template */
69 #define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \
70 static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \
72 void *data, void *ent)\
74 return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\
76 static const char PRINT_TYPE_FMT_NAME(type)[] = fmt;
78 DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int)
79 DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int)
80 DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long)
81 DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long)
82 DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int)
83 DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int)
84 DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long)
85 DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long)
87 /* data_rloc: data relative location, compatible with u32 */
88 #define make_data_rloc(len, roffs) \
89 (((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
90 #define get_rloc_len(dl) ((u32)(dl) >> 16)
91 #define get_rloc_offs(dl) ((u32)(dl) & 0xffff)
93 static inline void *get_rloc_data(u32 *dl)
95 return (u8 *)dl + get_rloc_offs(*dl);
98 /* For data_loc conversion */
99 static inline void *get_loc_data(u32 *dl, void *ent)
101 return (u8 *)ent + get_rloc_offs(*dl);
105 * Convert data_rloc to data_loc:
106 * data_rloc stores the offset from data_rloc itself, but data_loc
107 * stores the offset from event entry.
109 #define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs))
111 /* For defining macros, define string/string_size types */
113 typedef u32 string_size;
115 /* Print type function for string type */
116 static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
118 void *data, void *ent)
120 int len = *(u32 *)data >> 16;
123 return trace_seq_printf(s, " %s=(fault)", name);
125 return trace_seq_printf(s, " %s=\"%s\"", name,
126 (const char *)get_loc_data(data, ent));
128 static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";
130 /* Data fetch function type */
131 typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
138 static __kprobes void call_fetch(struct fetch_param *fprm,
139 struct pt_regs *regs, void *dest)
141 return fprm->fn(regs, fprm->data, dest);
144 #define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
146 * Define macro for basic types - we don't need to define s* types, because
147 * we have to care only about bitwidth at recording time.
149 #define DEFINE_BASIC_FETCH_FUNCS(method) \
150 DEFINE_FETCH_##method(u8) \
151 DEFINE_FETCH_##method(u16) \
152 DEFINE_FETCH_##method(u32) \
153 DEFINE_FETCH_##method(u64)
155 #define CHECK_FETCH_FUNCS(method, fn) \
156 (((FETCH_FUNC_NAME(method, u8) == fn) || \
157 (FETCH_FUNC_NAME(method, u16) == fn) || \
158 (FETCH_FUNC_NAME(method, u32) == fn) || \
159 (FETCH_FUNC_NAME(method, u64) == fn) || \
160 (FETCH_FUNC_NAME(method, string) == fn) || \
161 (FETCH_FUNC_NAME(method, string_size) == fn)) \
164 /* Data fetch function templates */
165 #define DEFINE_FETCH_reg(type) \
166 static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \
167 void *offset, void *dest) \
169 *(type *)dest = (type)regs_get_register(regs, \
170 (unsigned int)((unsigned long)offset)); \
172 DEFINE_BASIC_FETCH_FUNCS(reg)
173 /* No string on the register */
174 #define fetch_reg_string NULL
175 #define fetch_reg_string_size NULL
177 #define DEFINE_FETCH_stack(type) \
178 static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
179 void *offset, void *dest) \
181 *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \
182 (unsigned int)((unsigned long)offset)); \
184 DEFINE_BASIC_FETCH_FUNCS(stack)
185 /* No string on the stack entry */
186 #define fetch_stack_string NULL
187 #define fetch_stack_string_size NULL
189 #define DEFINE_FETCH_retval(type) \
190 static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\
191 void *dummy, void *dest) \
193 *(type *)dest = (type)regs_return_value(regs); \
195 DEFINE_BASIC_FETCH_FUNCS(retval)
196 /* No string on the retval */
197 #define fetch_retval_string NULL
198 #define fetch_retval_string_size NULL
200 #define DEFINE_FETCH_memory(type) \
201 static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
202 void *addr, void *dest) \
205 if (probe_kernel_address(addr, retval)) \
208 *(type *)dest = retval; \
210 DEFINE_BASIC_FETCH_FUNCS(memory)
212 * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
213 * length and relative data location.
215 static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
216 void *addr, void *dest)
219 int maxlen = get_rloc_len(*(u32 *)dest);
220 u8 *dst = get_rloc_data(dest);
222 mm_segment_t old_fs = get_fs();
226 * Try to get string again, since the string can be changed while
232 ret = __copy_from_user_inatomic(dst++, src++, 1);
233 while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen);
238 if (ret < 0) { /* Failed to fetch string */
239 ((u8 *)get_rloc_data(dest))[0] = '\0';
240 *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest));
242 *(u32 *)dest = make_data_rloc(src - (u8 *)addr,
243 get_rloc_offs(*(u32 *)dest));
245 /* Return the length of string -- including null terminal byte */
246 static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
247 void *addr, void *dest)
251 mm_segment_t old_fs = get_fs();
256 ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1);
258 } while (c && ret == 0 && len < MAX_STRING_SIZE);
262 if (ret < 0) /* Failed to check the length */
268 /* Memory fetching by symbol */
269 struct symbol_cache {
275 static unsigned long update_symbol_cache(struct symbol_cache *sc)
277 sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol);
279 sc->addr += sc->offset;
283 static void free_symbol_cache(struct symbol_cache *sc)
289 static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset)
291 struct symbol_cache *sc;
293 if (!sym || strlen(sym) == 0)
295 sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL);
299 sc->symbol = kstrdup(sym, GFP_KERNEL);
306 update_symbol_cache(sc);
310 #define DEFINE_FETCH_symbol(type) \
311 static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\
312 void *data, void *dest) \
314 struct symbol_cache *sc = data; \
316 fetch_memory_##type(regs, (void *)sc->addr, dest); \
320 DEFINE_BASIC_FETCH_FUNCS(symbol)
321 DEFINE_FETCH_symbol(string)
322 DEFINE_FETCH_symbol(string_size)
324 /* Dereference memory access function */
325 struct deref_fetch_param {
326 struct fetch_param orig;
330 #define DEFINE_FETCH_deref(type) \
331 static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\
332 void *data, void *dest) \
334 struct deref_fetch_param *dprm = data; \
335 unsigned long addr; \
336 call_fetch(&dprm->orig, regs, &addr); \
338 addr += dprm->offset; \
339 fetch_memory_##type(regs, (void *)addr, dest); \
343 DEFINE_BASIC_FETCH_FUNCS(deref)
344 DEFINE_FETCH_deref(string)
345 DEFINE_FETCH_deref(string_size)
347 static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data)
349 if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
350 free_deref_fetch_param(data->orig.data);
351 else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
352 free_symbol_cache(data->orig.data);
356 /* Default (unsigned long) fetch type */
357 #define __DEFAULT_FETCH_TYPE(t) u##t
358 #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
359 #define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
360 #define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
373 #define ASSIGN_FETCH_FUNC(method, type) \
374 [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type)
376 #define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
380 .print = PRINT_TYPE_FUNC_NAME(ptype), \
381 .fmt = PRINT_TYPE_FMT_NAME(ptype), \
382 .fmttype = _fmttype, \
384 ASSIGN_FETCH_FUNC(reg, ftype), \
385 ASSIGN_FETCH_FUNC(stack, ftype), \
386 ASSIGN_FETCH_FUNC(retval, ftype), \
387 ASSIGN_FETCH_FUNC(memory, ftype), \
388 ASSIGN_FETCH_FUNC(symbol, ftype), \
389 ASSIGN_FETCH_FUNC(deref, ftype), \
393 #define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
394 __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
396 #define FETCH_TYPE_STRING 0
397 #define FETCH_TYPE_STRSIZE 1
399 /* Fetch type information table */
400 static const struct fetch_type {
401 const char *name; /* Name of type */
402 size_t size; /* Byte size of type */
403 int is_signed; /* Signed flag */
404 print_type_func_t print; /* Print functions */
405 const char *fmt; /* Fromat string */
406 const char *fmttype; /* Name in format file */
407 /* Fetch functions */
408 fetch_func_t fetch[FETCH_MTD_END];
409 } fetch_type_table[] = {
411 [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string,
412 sizeof(u32), 1, "__data_loc char[]"),
413 [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32,
414 string_size, sizeof(u32), 0, "u32"),
416 ASSIGN_FETCH_TYPE(u8, u8, 0),
417 ASSIGN_FETCH_TYPE(u16, u16, 0),
418 ASSIGN_FETCH_TYPE(u32, u32, 0),
419 ASSIGN_FETCH_TYPE(u64, u64, 0),
420 ASSIGN_FETCH_TYPE(s8, u8, 1),
421 ASSIGN_FETCH_TYPE(s16, u16, 1),
422 ASSIGN_FETCH_TYPE(s32, u32, 1),
423 ASSIGN_FETCH_TYPE(s64, u64, 1),
426 static const struct fetch_type *find_fetch_type(const char *type)
431 type = DEFAULT_FETCH_TYPE_STR;
433 for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++)
434 if (strcmp(type, fetch_type_table[i].name) == 0)
435 return &fetch_type_table[i];
439 /* Special function : only accept unsigned long */
440 static __kprobes void fetch_stack_address(struct pt_regs *regs,
441 void *dummy, void *dest)
443 *(unsigned long *)dest = kernel_stack_pointer(regs);
446 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
447 fetch_func_t orig_fn)
451 if (type != &fetch_type_table[FETCH_TYPE_STRING])
452 return NULL; /* Only string type needs size function */
453 for (i = 0; i < FETCH_MTD_END; i++)
454 if (type->fetch[i] == orig_fn)
455 return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i];
457 WARN_ON(1); /* This should not happen */
462 * Kprobe event core functions
466 struct fetch_param fetch;
467 struct fetch_param fetch_size;
468 unsigned int offset; /* Offset from argument entry */
469 const char *name; /* Name of this argument */
470 const char *comm; /* Command of this argument */
471 const struct fetch_type *type; /* Type of this argument */
474 /* Flags for trace_probe */
475 #define TP_FLAG_TRACE 1
476 #define TP_FLAG_PROFILE 2
479 struct list_head list;
480 struct kretprobe rp; /* Use rp.kp for kprobe use */
482 unsigned int flags; /* For TP_FLAG_* */
483 const char *symbol; /* symbol name */
484 struct ftrace_event_class class;
485 struct ftrace_event_call call;
486 ssize_t size; /* trace entry size */
487 unsigned int nr_args;
488 struct probe_arg args[];
491 #define SIZEOF_TRACE_PROBE(n) \
492 (offsetof(struct trace_probe, args) + \
493 (sizeof(struct probe_arg) * (n)))
496 static __kprobes int probe_is_return(struct trace_probe *tp)
498 return tp->rp.handler != NULL;
501 static __kprobes const char *probe_symbol(struct trace_probe *tp)
503 return tp->symbol ? tp->symbol : "unknown";
506 static int register_probe_event(struct trace_probe *tp);
507 static void unregister_probe_event(struct trace_probe *tp);
509 static DEFINE_MUTEX(probe_lock);
510 static LIST_HEAD(probe_list);
512 static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
513 static int kretprobe_dispatcher(struct kretprobe_instance *ri,
514 struct pt_regs *regs);
516 /* Check the name is good for event/group/fields */
517 static int is_good_name(const char *name)
519 if (!isalpha(*name) && *name != '_')
521 while (*++name != '\0') {
522 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
529 * Allocate new trace_probe and initialize it (including kprobes).
531 static struct trace_probe *alloc_trace_probe(const char *group,
536 int nargs, int is_return)
538 struct trace_probe *tp;
541 tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL);
546 tp->symbol = kstrdup(symbol, GFP_KERNEL);
549 tp->rp.kp.symbol_name = tp->symbol;
550 tp->rp.kp.offset = offs;
552 tp->rp.kp.addr = addr;
555 tp->rp.handler = kretprobe_dispatcher;
557 tp->rp.kp.pre_handler = kprobe_dispatcher;
559 if (!event || !is_good_name(event)) {
564 tp->call.class = &tp->class;
565 tp->call.name = kstrdup(event, GFP_KERNEL);
569 if (!group || !is_good_name(group)) {
574 tp->class.system = kstrdup(group, GFP_KERNEL);
575 if (!tp->class.system)
578 INIT_LIST_HEAD(&tp->list);
581 kfree(tp->call.name);
587 static void free_probe_arg(struct probe_arg *arg)
589 if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
590 free_deref_fetch_param(arg->fetch.data);
591 else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
592 free_symbol_cache(arg->fetch.data);
597 static void free_trace_probe(struct trace_probe *tp)
601 for (i = 0; i < tp->nr_args; i++)
602 free_probe_arg(&tp->args[i]);
604 kfree(tp->call.class->system);
605 kfree(tp->call.name);
610 static struct trace_probe *find_probe_event(const char *event,
613 struct trace_probe *tp;
615 list_for_each_entry(tp, &probe_list, list)
616 if (strcmp(tp->call.name, event) == 0 &&
617 strcmp(tp->call.class->system, group) == 0)
622 /* Unregister a trace_probe and probe_event: call with locking probe_lock */
623 static void unregister_trace_probe(struct trace_probe *tp)
625 if (probe_is_return(tp))
626 unregister_kretprobe(&tp->rp);
628 unregister_kprobe(&tp->rp.kp);
630 unregister_probe_event(tp);
633 /* Register a trace_probe and probe_event */
634 static int register_trace_probe(struct trace_probe *tp)
636 struct trace_probe *old_tp;
639 mutex_lock(&probe_lock);
641 /* register as an event */
642 old_tp = find_probe_event(tp->call.name, tp->call.class->system);
644 /* delete old event */
645 unregister_trace_probe(old_tp);
646 free_trace_probe(old_tp);
648 ret = register_probe_event(tp);
650 pr_warning("Failed to register probe event(%d)\n", ret);
654 tp->rp.kp.flags |= KPROBE_FLAG_DISABLED;
655 if (probe_is_return(tp))
656 ret = register_kretprobe(&tp->rp);
658 ret = register_kprobe(&tp->rp.kp);
661 pr_warning("Could not insert probe(%d)\n", ret);
662 if (ret == -EILSEQ) {
663 pr_warning("Probing address(0x%p) is not an "
664 "instruction boundary.\n",
668 unregister_probe_event(tp);
670 list_add_tail(&tp->list, &probe_list);
672 mutex_unlock(&probe_lock);
676 /* Split symbol and offset. */
677 static int split_symbol_offset(char *symbol, unsigned long *offset)
685 tmp = strchr(symbol, '+');
687 /* skip sign because strict_strtol doesn't accept '+' */
688 ret = strict_strtoul(tmp + 1, 0, offset);
697 #define PARAM_MAX_ARGS 16
698 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
700 static int parse_probe_vars(char *arg, const struct fetch_type *t,
701 struct fetch_param *f, int is_return)
706 if (strcmp(arg, "retval") == 0) {
708 f->fn = t->fetch[FETCH_MTD_retval];
711 } else if (strncmp(arg, "stack", 5) == 0) {
712 if (arg[5] == '\0') {
713 if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
714 f->fn = fetch_stack_address;
717 } else if (isdigit(arg[5])) {
718 ret = strict_strtoul(arg + 5, 10, ¶m);
719 if (ret || param > PARAM_MAX_STACK)
722 f->fn = t->fetch[FETCH_MTD_stack];
723 f->data = (void *)param;
732 /* Recursive argument parser */
733 static int __parse_probe_arg(char *arg, const struct fetch_type *t,
734 struct fetch_param *f, int is_return)
743 ret = parse_probe_vars(arg + 1, t, f, is_return);
745 case '%': /* named register */
746 ret = regs_query_register_offset(arg + 1);
748 f->fn = t->fetch[FETCH_MTD_reg];
749 f->data = (void *)(unsigned long)ret;
753 case '@': /* memory or symbol */
754 if (isdigit(arg[1])) {
755 ret = strict_strtoul(arg + 1, 0, ¶m);
758 f->fn = t->fetch[FETCH_MTD_memory];
759 f->data = (void *)param;
761 ret = split_symbol_offset(arg + 1, &offset);
764 f->data = alloc_symbol_cache(arg + 1, offset);
766 f->fn = t->fetch[FETCH_MTD_symbol];
769 case '+': /* deref memory */
770 arg++; /* Skip '+', because strict_strtol() rejects it. */
772 tmp = strchr(arg, '(');
776 ret = strict_strtol(arg, 0, &offset);
780 tmp = strrchr(arg, ')');
782 struct deref_fetch_param *dprm;
783 const struct fetch_type *t2 = find_fetch_type(NULL);
785 dprm = kzalloc(sizeof(struct deref_fetch_param),
789 dprm->offset = offset;
790 ret = __parse_probe_arg(arg, t2, &dprm->orig,
795 f->fn = t->fetch[FETCH_MTD_deref];
796 f->data = (void *)dprm;
801 if (!ret && !f->fn) { /* Parsed, but do not find fetch method */
802 pr_info("%s type has no corresponding fetch method.\n",
809 /* String length checking wrapper */
810 static int parse_probe_arg(char *arg, struct trace_probe *tp,
811 struct probe_arg *parg, int is_return)
816 if (strlen(arg) > MAX_ARGSTR_LEN) {
817 pr_info("Argument is too long.: %s\n", arg);
820 parg->comm = kstrdup(arg, GFP_KERNEL);
822 pr_info("Failed to allocate memory for command '%s'.\n", arg);
825 t = strchr(parg->comm, ':');
827 arg[t - parg->comm] = '\0';
830 parg->type = find_fetch_type(t);
832 pr_info("Unsupported type: %s\n", t);
835 parg->offset = tp->size;
836 tp->size += parg->type->size;
837 ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return);
839 parg->fetch_size.fn = get_fetch_size_function(parg->type,
841 parg->fetch_size.data = parg->fetch.data;
846 /* Return 1 if name is reserved or already used by another argument */
847 static int conflict_field_name(const char *name,
848 struct probe_arg *args, int narg)
851 for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++)
852 if (strcmp(reserved_field_names[i], name) == 0)
854 for (i = 0; i < narg; i++)
855 if (strcmp(args[i].name, name) == 0)
860 static int create_trace_probe(int argc, char **argv)
864 * - Add kprobe: p[:[GRP/]EVENT] KSYM[+OFFS]|KADDR [FETCHARGS]
865 * - Add kretprobe: r[:[GRP/]EVENT] KSYM[+0] [FETCHARGS]
867 * $retval : fetch return value
868 * $stack : fetch stack address
869 * $stackN : fetch Nth of stack (N:0-)
870 * @ADDR : fetch memory at ADDR (ADDR should be in kernel)
871 * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
872 * %REG : fetch register REG
873 * Dereferencing memory fetch:
874 * +|-offs(ARG) : fetch memory at ARG +|- offs address.
875 * Alias name of args:
876 * NAME=FETCHARG : set NAME as alias of FETCHARG.
878 * FETCHARG:TYPE : use TYPE instead of unsigned long.
880 struct trace_probe *tp;
882 int is_return = 0, is_delete = 0;
883 char *symbol = NULL, *event = NULL, *group = NULL;
885 unsigned long offset = 0;
887 char buf[MAX_EVENT_NAME_LEN];
889 /* argc must be >= 1 */
890 if (argv[0][0] == 'p')
892 else if (argv[0][0] == 'r')
894 else if (argv[0][0] == '-')
897 pr_info("Probe definition must be started with 'p', 'r' or"
902 if (argv[0][1] == ':') {
904 if (strchr(event, '/')) {
906 event = strchr(group, '/') + 1;
908 if (strlen(group) == 0) {
909 pr_info("Group name is not specified\n");
913 if (strlen(event) == 0) {
914 pr_info("Event name is not specified\n");
919 group = KPROBE_EVENT_SYSTEM;
923 pr_info("Delete command needs an event name.\n");
926 mutex_lock(&probe_lock);
927 tp = find_probe_event(event, group);
929 mutex_unlock(&probe_lock);
930 pr_info("Event %s/%s doesn't exist.\n", group, event);
933 /* delete an event */
934 unregister_trace_probe(tp);
935 free_trace_probe(tp);
936 mutex_unlock(&probe_lock);
941 pr_info("Probe point is not specified.\n");
944 if (isdigit(argv[1][0])) {
946 pr_info("Return probe point must be a symbol.\n");
949 /* an address specified */
950 ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr);
952 pr_info("Failed to parse address.\n");
956 /* a symbol specified */
958 /* TODO: support .init module functions */
959 ret = split_symbol_offset(symbol, &offset);
961 pr_info("Failed to parse symbol.\n");
964 if (offset && is_return) {
965 pr_info("Return probe must be used without offset.\n");
969 argc -= 2; argv += 2;
973 /* Make a new event name */
975 snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
976 is_return ? 'r' : 'p', symbol, offset);
978 snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
979 is_return ? 'r' : 'p', addr);
982 tp = alloc_trace_probe(group, event, addr, symbol, offset, argc,
985 pr_info("Failed to allocate trace_probe.(%d)\n",
990 /* parse arguments */
992 for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
993 /* Increment count for freeing args in error case */
996 /* Parse argument name */
997 arg = strchr(argv[i], '=');
1000 tp->args[i].name = kstrdup(argv[i], GFP_KERNEL);
1003 /* If argument name is omitted, set "argN" */
1004 snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1);
1005 tp->args[i].name = kstrdup(buf, GFP_KERNEL);
1008 if (!tp->args[i].name) {
1009 pr_info("Failed to allocate argument[%d] name.\n", i);
1014 if (!is_good_name(tp->args[i].name)) {
1015 pr_info("Invalid argument[%d] name: %s\n",
1016 i, tp->args[i].name);
1021 if (conflict_field_name(tp->args[i].name, tp->args, i)) {
1022 pr_info("Argument[%d] name '%s' conflicts with "
1023 "another field.\n", i, argv[i]);
1028 /* Parse fetch argument */
1029 ret = parse_probe_arg(arg, tp, &tp->args[i], is_return);
1031 pr_info("Parse error at argument[%d]. (%d)\n", i, ret);
1036 ret = register_trace_probe(tp);
1042 free_trace_probe(tp);
1046 static void cleanup_all_probes(void)
1048 struct trace_probe *tp;
1050 mutex_lock(&probe_lock);
1051 /* TODO: Use batch unregistration */
1052 while (!list_empty(&probe_list)) {
1053 tp = list_entry(probe_list.next, struct trace_probe, list);
1054 unregister_trace_probe(tp);
1055 free_trace_probe(tp);
1057 mutex_unlock(&probe_lock);
1061 /* Probes listing interfaces */
1062 static void *probes_seq_start(struct seq_file *m, loff_t *pos)
1064 mutex_lock(&probe_lock);
1065 return seq_list_start(&probe_list, *pos);
1068 static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos)
1070 return seq_list_next(v, &probe_list, pos);
1073 static void probes_seq_stop(struct seq_file *m, void *v)
1075 mutex_unlock(&probe_lock);
1078 static int probes_seq_show(struct seq_file *m, void *v)
1080 struct trace_probe *tp = v;
1083 seq_printf(m, "%c", probe_is_return(tp) ? 'r' : 'p');
1084 seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name);
1087 seq_printf(m, " 0x%p", tp->rp.kp.addr);
1088 else if (tp->rp.kp.offset)
1089 seq_printf(m, " %s+%u", probe_symbol(tp), tp->rp.kp.offset);
1091 seq_printf(m, " %s", probe_symbol(tp));
1093 for (i = 0; i < tp->nr_args; i++)
1094 seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm);
1095 seq_printf(m, "\n");
1100 static const struct seq_operations probes_seq_op = {
1101 .start = probes_seq_start,
1102 .next = probes_seq_next,
1103 .stop = probes_seq_stop,
1104 .show = probes_seq_show
1107 static int probes_open(struct inode *inode, struct file *file)
1109 if ((file->f_mode & FMODE_WRITE) &&
1110 (file->f_flags & O_TRUNC))
1111 cleanup_all_probes();
1113 return seq_open(file, &probes_seq_op);
1116 static int command_trace_probe(const char *buf)
1119 int argc = 0, ret = 0;
1121 argv = argv_split(GFP_KERNEL, buf, &argc);
1126 ret = create_trace_probe(argc, argv);
1132 #define WRITE_BUFSIZE 128
1134 static ssize_t probes_write(struct file *file, const char __user *buffer,
1135 size_t count, loff_t *ppos)
1142 kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL);
1147 while (done < count) {
1148 size = count - done;
1149 if (size >= WRITE_BUFSIZE)
1150 size = WRITE_BUFSIZE - 1;
1151 if (copy_from_user(kbuf, buffer + done, size)) {
1156 tmp = strchr(kbuf, '\n');
1159 size = tmp - kbuf + 1;
1160 } else if (done + size < count) {
1161 pr_warning("Line length is too long: "
1162 "Should be less than %d.", WRITE_BUFSIZE);
1167 /* Remove comments */
1168 tmp = strchr(kbuf, '#');
1172 ret = command_trace_probe(kbuf);
1182 static const struct file_operations kprobe_events_ops = {
1183 .owner = THIS_MODULE,
1184 .open = probes_open,
1186 .llseek = seq_lseek,
1187 .release = seq_release,
1188 .write = probes_write,
1191 /* Probes profiling interfaces */
1192 static int probes_profile_seq_show(struct seq_file *m, void *v)
1194 struct trace_probe *tp = v;
1196 seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit,
1202 static const struct seq_operations profile_seq_op = {
1203 .start = probes_seq_start,
1204 .next = probes_seq_next,
1205 .stop = probes_seq_stop,
1206 .show = probes_profile_seq_show
1209 static int profile_open(struct inode *inode, struct file *file)
1211 return seq_open(file, &profile_seq_op);
1214 static const struct file_operations kprobe_profile_ops = {
1215 .owner = THIS_MODULE,
1216 .open = profile_open,
1218 .llseek = seq_lseek,
1219 .release = seq_release,
1222 /* Sum up total data length for dynamic arraies (strings) */
1223 static __kprobes int __get_data_size(struct trace_probe *tp,
1224 struct pt_regs *regs)
1229 for (i = 0; i < tp->nr_args; i++)
1230 if (unlikely(tp->args[i].fetch_size.fn)) {
1231 call_fetch(&tp->args[i].fetch_size, regs, &len);
1238 /* Store the value of each argument */
1239 static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp,
1240 struct pt_regs *regs,
1241 u8 *data, int maxlen)
1245 u32 *dl; /* Data (relative) location */
1247 for (i = 0; i < tp->nr_args; i++) {
1248 if (unlikely(tp->args[i].fetch_size.fn)) {
1250 * First, we set the relative location and
1251 * maximum data length to *dl
1253 dl = (u32 *)(data + tp->args[i].offset);
1254 *dl = make_data_rloc(maxlen, end - tp->args[i].offset);
1255 /* Then try to fetch string or dynamic array data */
1256 call_fetch(&tp->args[i].fetch, regs, dl);
1257 /* Reduce maximum length */
1258 end += get_rloc_len(*dl);
1259 maxlen -= get_rloc_len(*dl);
1260 /* Trick here, convert data_rloc to data_loc */
1261 *dl = convert_rloc_to_loc(*dl,
1262 ent_size + tp->args[i].offset);
1264 /* Just fetching data normally */
1265 call_fetch(&tp->args[i].fetch, regs,
1266 data + tp->args[i].offset);
1270 /* Kprobe handler */
1271 static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
1273 struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
1274 struct kprobe_trace_entry_head *entry;
1275 struct ring_buffer_event *event;
1276 struct ring_buffer *buffer;
1277 int size, dsize, pc;
1278 unsigned long irq_flags;
1279 struct ftrace_event_call *call = &tp->call;
1283 local_save_flags(irq_flags);
1284 pc = preempt_count();
1286 dsize = __get_data_size(tp, regs);
1287 size = sizeof(*entry) + tp->size + dsize;
1289 event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
1290 size, irq_flags, pc);
1294 entry = ring_buffer_event_data(event);
1295 entry->ip = (unsigned long)kp->addr;
1296 store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
1298 if (!filter_current_check_discard(buffer, call, entry, event))
1299 trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
1302 /* Kretprobe handler */
1303 static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
1304 struct pt_regs *regs)
1306 struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
1307 struct kretprobe_trace_entry_head *entry;
1308 struct ring_buffer_event *event;
1309 struct ring_buffer *buffer;
1310 int size, pc, dsize;
1311 unsigned long irq_flags;
1312 struct ftrace_event_call *call = &tp->call;
1314 local_save_flags(irq_flags);
1315 pc = preempt_count();
1317 dsize = __get_data_size(tp, regs);
1318 size = sizeof(*entry) + tp->size + dsize;
1320 event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
1321 size, irq_flags, pc);
1325 entry = ring_buffer_event_data(event);
1326 entry->func = (unsigned long)tp->rp.kp.addr;
1327 entry->ret_ip = (unsigned long)ri->ret_addr;
1328 store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
1330 if (!filter_current_check_discard(buffer, call, entry, event))
1331 trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
1334 /* Event entry printers */
1336 print_kprobe_event(struct trace_iterator *iter, int flags,
1337 struct trace_event *event)
1339 struct kprobe_trace_entry_head *field;
1340 struct trace_seq *s = &iter->seq;
1341 struct trace_probe *tp;
1345 field = (struct kprobe_trace_entry_head *)iter->ent;
1346 tp = container_of(event, struct trace_probe, call.event);
1348 if (!trace_seq_printf(s, "%s: (", tp->call.name))
1351 if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
1354 if (!trace_seq_puts(s, ")"))
1357 data = (u8 *)&field[1];
1358 for (i = 0; i < tp->nr_args; i++)
1359 if (!tp->args[i].type->print(s, tp->args[i].name,
1360 data + tp->args[i].offset, field))
1363 if (!trace_seq_puts(s, "\n"))
1366 return TRACE_TYPE_HANDLED;
1368 return TRACE_TYPE_PARTIAL_LINE;
1372 print_kretprobe_event(struct trace_iterator *iter, int flags,
1373 struct trace_event *event)
1375 struct kretprobe_trace_entry_head *field;
1376 struct trace_seq *s = &iter->seq;
1377 struct trace_probe *tp;
1381 field = (struct kretprobe_trace_entry_head *)iter->ent;
1382 tp = container_of(event, struct trace_probe, call.event);
1384 if (!trace_seq_printf(s, "%s: (", tp->call.name))
1387 if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
1390 if (!trace_seq_puts(s, " <- "))
1393 if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
1396 if (!trace_seq_puts(s, ")"))
1399 data = (u8 *)&field[1];
1400 for (i = 0; i < tp->nr_args; i++)
1401 if (!tp->args[i].type->print(s, tp->args[i].name,
1402 data + tp->args[i].offset, field))
1405 if (!trace_seq_puts(s, "\n"))
1408 return TRACE_TYPE_HANDLED;
1410 return TRACE_TYPE_PARTIAL_LINE;
1413 static int probe_event_enable(struct ftrace_event_call *call)
1415 struct trace_probe *tp = (struct trace_probe *)call->data;
1417 tp->flags |= TP_FLAG_TRACE;
1418 if (probe_is_return(tp))
1419 return enable_kretprobe(&tp->rp);
1421 return enable_kprobe(&tp->rp.kp);
1424 static void probe_event_disable(struct ftrace_event_call *call)
1426 struct trace_probe *tp = (struct trace_probe *)call->data;
1428 tp->flags &= ~TP_FLAG_TRACE;
1429 if (!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE))) {
1430 if (probe_is_return(tp))
1431 disable_kretprobe(&tp->rp);
1433 disable_kprobe(&tp->rp.kp);
1438 #define DEFINE_FIELD(type, item, name, is_signed) \
1440 ret = trace_define_field(event_call, #type, name, \
1441 offsetof(typeof(field), item), \
1442 sizeof(field.item), is_signed, \
1448 static int kprobe_event_define_fields(struct ftrace_event_call *event_call)
1451 struct kprobe_trace_entry_head field;
1452 struct trace_probe *tp = (struct trace_probe *)event_call->data;
1454 DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
1455 /* Set argument names as fields */
1456 for (i = 0; i < tp->nr_args; i++) {
1457 ret = trace_define_field(event_call, tp->args[i].type->fmttype,
1459 sizeof(field) + tp->args[i].offset,
1460 tp->args[i].type->size,
1461 tp->args[i].type->is_signed,
1469 static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
1472 struct kretprobe_trace_entry_head field;
1473 struct trace_probe *tp = (struct trace_probe *)event_call->data;
1475 DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
1476 DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
1477 /* Set argument names as fields */
1478 for (i = 0; i < tp->nr_args; i++) {
1479 ret = trace_define_field(event_call, tp->args[i].type->fmttype,
1481 sizeof(field) + tp->args[i].offset,
1482 tp->args[i].type->size,
1483 tp->args[i].type->is_signed,
1491 static int __set_print_fmt(struct trace_probe *tp, char *buf, int len)
1496 const char *fmt, *arg;
1498 if (!probe_is_return(tp)) {
1500 arg = "REC->" FIELD_STRING_IP;
1502 fmt = "(%lx <- %lx)";
1503 arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
1506 /* When len=0, we just calculate the needed length */
1507 #define LEN_OR_ZERO (len ? len - pos : 0)
1509 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
1511 for (i = 0; i < tp->nr_args; i++) {
1512 pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s",
1513 tp->args[i].name, tp->args[i].type->fmt);
1516 pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
1518 for (i = 0; i < tp->nr_args; i++) {
1519 if (strcmp(tp->args[i].type->name, "string") == 0)
1520 pos += snprintf(buf + pos, LEN_OR_ZERO,
1524 pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s",
1530 /* return the length of print_fmt */
1534 static int set_print_fmt(struct trace_probe *tp)
1539 /* First: called with 0 length to calculate the needed length */
1540 len = __set_print_fmt(tp, NULL, 0);
1541 print_fmt = kmalloc(len + 1, GFP_KERNEL);
1545 /* Second: actually write the @print_fmt */
1546 __set_print_fmt(tp, print_fmt, len + 1);
1547 tp->call.print_fmt = print_fmt;
1552 #ifdef CONFIG_PERF_EVENTS
1554 /* Kprobe profile handler */
1555 static __kprobes void kprobe_perf_func(struct kprobe *kp,
1556 struct pt_regs *regs)
1558 struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
1559 struct ftrace_event_call *call = &tp->call;
1560 struct kprobe_trace_entry_head *entry;
1561 struct hlist_head *head;
1562 int size, __size, dsize;
1565 dsize = __get_data_size(tp, regs);
1566 __size = sizeof(*entry) + tp->size + dsize;
1567 size = ALIGN(__size + sizeof(u32), sizeof(u64));
1568 size -= sizeof(u32);
1569 if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
1570 "profile buffer not large enough"))
1573 entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
1577 entry->ip = (unsigned long)kp->addr;
1578 memset(&entry[1], 0, dsize);
1579 store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
1581 head = this_cpu_ptr(call->perf_events);
1582 perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, regs, head);
1585 /* Kretprobe profile handler */
1586 static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
1587 struct pt_regs *regs)
1589 struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
1590 struct ftrace_event_call *call = &tp->call;
1591 struct kretprobe_trace_entry_head *entry;
1592 struct hlist_head *head;
1593 int size, __size, dsize;
1596 dsize = __get_data_size(tp, regs);
1597 __size = sizeof(*entry) + tp->size + dsize;
1598 size = ALIGN(__size + sizeof(u32), sizeof(u64));
1599 size -= sizeof(u32);
1600 if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
1601 "profile buffer not large enough"))
1604 entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
1608 entry->func = (unsigned long)tp->rp.kp.addr;
1609 entry->ret_ip = (unsigned long)ri->ret_addr;
1610 store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
1612 head = this_cpu_ptr(call->perf_events);
1613 perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1, regs, head);
1616 static int probe_perf_enable(struct ftrace_event_call *call)
1618 struct trace_probe *tp = (struct trace_probe *)call->data;
1620 tp->flags |= TP_FLAG_PROFILE;
1622 if (probe_is_return(tp))
1623 return enable_kretprobe(&tp->rp);
1625 return enable_kprobe(&tp->rp.kp);
1628 static void probe_perf_disable(struct ftrace_event_call *call)
1630 struct trace_probe *tp = (struct trace_probe *)call->data;
1632 tp->flags &= ~TP_FLAG_PROFILE;
1634 if (!(tp->flags & TP_FLAG_TRACE)) {
1635 if (probe_is_return(tp))
1636 disable_kretprobe(&tp->rp);
1638 disable_kprobe(&tp->rp.kp);
1641 #endif /* CONFIG_PERF_EVENTS */
1644 int kprobe_register(struct ftrace_event_call *event, enum trace_reg type)
1647 case TRACE_REG_REGISTER:
1648 return probe_event_enable(event);
1649 case TRACE_REG_UNREGISTER:
1650 probe_event_disable(event);
1653 #ifdef CONFIG_PERF_EVENTS
1654 case TRACE_REG_PERF_REGISTER:
1655 return probe_perf_enable(event);
1656 case TRACE_REG_PERF_UNREGISTER:
1657 probe_perf_disable(event);
1665 int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
1667 struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
1669 if (tp->flags & TP_FLAG_TRACE)
1670 kprobe_trace_func(kp, regs);
1671 #ifdef CONFIG_PERF_EVENTS
1672 if (tp->flags & TP_FLAG_PROFILE)
1673 kprobe_perf_func(kp, regs);
1675 return 0; /* We don't tweek kernel, so just return 0 */
1679 int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
1681 struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
1683 if (tp->flags & TP_FLAG_TRACE)
1684 kretprobe_trace_func(ri, regs);
1685 #ifdef CONFIG_PERF_EVENTS
1686 if (tp->flags & TP_FLAG_PROFILE)
1687 kretprobe_perf_func(ri, regs);
1689 return 0; /* We don't tweek kernel, so just return 0 */
1692 static struct trace_event_functions kretprobe_funcs = {
1693 .trace = print_kretprobe_event
1696 static struct trace_event_functions kprobe_funcs = {
1697 .trace = print_kprobe_event
1700 static int register_probe_event(struct trace_probe *tp)
1702 struct ftrace_event_call *call = &tp->call;
1705 /* Initialize ftrace_event_call */
1706 INIT_LIST_HEAD(&call->class->fields);
1707 if (probe_is_return(tp)) {
1708 call->event.funcs = &kretprobe_funcs;
1709 call->class->define_fields = kretprobe_event_define_fields;
1711 call->event.funcs = &kprobe_funcs;
1712 call->class->define_fields = kprobe_event_define_fields;
1714 if (set_print_fmt(tp) < 0)
1716 ret = register_ftrace_event(&call->event);
1718 kfree(call->print_fmt);
1722 call->class->reg = kprobe_register;
1724 ret = trace_add_event_call(call);
1726 pr_info("Failed to register kprobe event: %s\n", call->name);
1727 kfree(call->print_fmt);
1728 unregister_ftrace_event(&call->event);
1733 static void unregister_probe_event(struct trace_probe *tp)
1735 /* tp->event is unregistered in trace_remove_event_call() */
1736 trace_remove_event_call(&tp->call);
1737 kfree(tp->call.print_fmt);
1740 /* Make a debugfs interface for controling probe points */
1741 static __init int init_kprobe_trace(void)
1743 struct dentry *d_tracer;
1744 struct dentry *entry;
1746 d_tracer = tracing_init_dentry();
1750 entry = debugfs_create_file("kprobe_events", 0644, d_tracer,
1751 NULL, &kprobe_events_ops);
1753 /* Event list interface */
1755 pr_warning("Could not create debugfs "
1756 "'kprobe_events' entry\n");
1758 /* Profile interface */
1759 entry = debugfs_create_file("kprobe_profile", 0444, d_tracer,
1760 NULL, &kprobe_profile_ops);
1763 pr_warning("Could not create debugfs "
1764 "'kprobe_profile' entry\n");
1767 fs_initcall(init_kprobe_trace);
1770 #ifdef CONFIG_FTRACE_STARTUP_TEST
1772 static int kprobe_trace_selftest_target(int a1, int a2, int a3,
1773 int a4, int a5, int a6)
1775 return a1 + a2 + a3 + a4 + a5 + a6;
1778 static __init int kprobe_trace_self_tests_init(void)
1781 int (*target)(int, int, int, int, int, int);
1782 struct trace_probe *tp;
1784 target = kprobe_trace_selftest_target;
1786 pr_info("Testing kprobe tracing: ");
1788 ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target "
1789 "$stack $stack0 +0($stack)");
1790 if (WARN_ON_ONCE(ret)) {
1791 pr_warning("error on probing function entry.\n");
1794 /* Enable trace point */
1795 tp = find_probe_event("testprobe", KPROBE_EVENT_SYSTEM);
1796 if (WARN_ON_ONCE(tp == NULL)) {
1797 pr_warning("error on getting new probe.\n");
1800 probe_event_enable(&tp->call);
1803 ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target "
1805 if (WARN_ON_ONCE(ret)) {
1806 pr_warning("error on probing function return.\n");
1809 /* Enable trace point */
1810 tp = find_probe_event("testprobe2", KPROBE_EVENT_SYSTEM);
1811 if (WARN_ON_ONCE(tp == NULL)) {
1812 pr_warning("error on getting new probe.\n");
1815 probe_event_enable(&tp->call);
1821 ret = target(1, 2, 3, 4, 5, 6);
1823 ret = command_trace_probe("-:testprobe");
1824 if (WARN_ON_ONCE(ret)) {
1825 pr_warning("error on deleting a probe.\n");
1829 ret = command_trace_probe("-:testprobe2");
1830 if (WARN_ON_ONCE(ret)) {
1831 pr_warning("error on deleting a probe.\n");
1836 cleanup_all_probes();
1838 pr_cont("NG: Some tests are failed. Please check them.\n");
1844 late_initcall(kprobe_trace_self_tests_init);