/* * probe-event.c : perf-probe definition to probe_events format converter * * Written by Masami Hiramatsu * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * */ #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #undef _GNU_SOURCE #include "util.h" #include "event.h" #include "string.h" #include "strlist.h" #include "debug.h" #include "cache.h" #include "color.h" #include "symbol.h" #include "thread.h" #include "debugfs.h" #include "trace-event.h" /* For __unused */ #include "probe-event.h" #include "probe-finder.h" #define MAX_CMDLEN 256 #define MAX_PROBE_ARGS 128 #define PERFPROBE_GROUP "probe" bool probe_event_dry_run; /* Dry run flag */ #define semantic_error(msg ...) pr_err("Semantic error :" msg) /* If there is no space to write, returns -E2BIG. */ static int e_snprintf(char *str, size_t size, const char *format, ...) __attribute__((format(printf, 3, 4))); static int e_snprintf(char *str, size_t size, const char *format, ...) { int ret; va_list ap; va_start(ap, format); ret = vsnprintf(str, size, format, ap); va_end(ap); if (ret >= (int)size) ret = -E2BIG; return ret; } static char *synthesize_perf_probe_point(struct perf_probe_point *pp); static struct machine machine; /* Initialize symbol maps and path of vmlinux/modules */ static int init_vmlinux(void) { int ret; symbol_conf.sort_by_name = true; if (symbol_conf.vmlinux_name == NULL) symbol_conf.try_vmlinux_path = true; else pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name); ret = symbol__init(); if (ret < 0) { pr_debug("Failed to init symbol map.\n"); goto out; } ret = machine__init(&machine, "", HOST_KERNEL_ID); if (ret < 0) goto out; if (machine__create_kernel_maps(&machine) < 0) { pr_debug("machine__create_kernel_maps() failed.\n"); goto out; } out: if (ret < 0) pr_warning("Failed to init vmlinux path.\n"); return ret; } static struct symbol *__find_kernel_function_by_name(const char *name, struct map **mapp) { return machine__find_kernel_function_by_name(&machine, name, mapp, NULL); } const char *kernel_get_module_path(const char *module) { struct dso *dso; if (module) { list_for_each_entry(dso, &machine.kernel_dsos, node) { if (strncmp(dso->short_name + 1, module, dso->short_name_len - 2) == 0) goto found; } pr_debug("Failed to find module %s.\n", module); return NULL; } else { dso = machine.vmlinux_maps[MAP__FUNCTION]->dso; if (dso__load_vmlinux_path(dso, machine.vmlinux_maps[MAP__FUNCTION], NULL) < 0) { pr_debug("Failed to load kernel map.\n"); return NULL; } } found: return dso->long_name; } #ifdef DWARF_SUPPORT static int open_vmlinux(const char *module) { const char *path = kernel_get_module_path(module); if (!path) { pr_err("Failed to find path of %s module.\n", module ?: "kernel"); return -ENOENT; } pr_debug("Try to open %s\n", path); return open(path, O_RDONLY); } /* * Convert trace point to probe point with debuginfo * Currently only handles kprobes. */ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp, struct perf_probe_point *pp) { struct symbol *sym; struct map *map; u64 addr; int ret = -ENOENT; sym = __find_kernel_function_by_name(tp->symbol, &map); if (sym) { addr = map->unmap_ip(map, sym->start + tp->offset); pr_debug("try to find %s+%ld@%llx\n", tp->symbol, tp->offset, addr); ret = find_perf_probe_point((unsigned long)addr, pp); } if (ret <= 0) { pr_debug("Failed to find corresponding probes from " "debuginfo. Use kprobe event information.\n"); pp->function = strdup(tp->symbol); if (pp->function == NULL) return -ENOMEM; pp->offset = tp->offset; } pp->retprobe = tp->retprobe; return 0; } /* Try to find perf_probe_event with debuginfo */ static int try_to_find_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event **tevs, int max_tevs, const char *module) { bool need_dwarf = perf_probe_event_need_dwarf(pev); int fd, ntevs; fd = open_vmlinux(module); if (fd < 0) { if (need_dwarf) { pr_warning("Failed to open debuginfo file.\n"); return fd; } pr_debug("Could not open vmlinux. Try to use symbols.\n"); return 0; } /* Searching trace events corresponding to probe event */ ntevs = find_probe_trace_events(fd, pev, tevs, max_tevs); close(fd); if (ntevs > 0) { /* Succeeded to find trace events */ pr_debug("find %d probe_trace_events.\n", ntevs); return ntevs; } if (ntevs == 0) { /* No error but failed to find probe point. */ pr_warning("Probe point '%s' not found.\n", synthesize_perf_probe_point(&pev->point)); return -ENOENT; } /* Error path : ntevs < 0 */ pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs); if (ntevs == -EBADF) { pr_warning("Warning: No dwarf info found in the vmlinux - " "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n"); if (!need_dwarf) { pr_debug("Trying to use symbols.\n"); return 0; } } return ntevs; } /* * Find a src file from a DWARF tag path. Prepend optional source path prefix * and chop off leading directories that do not exist. Result is passed back as * a newly allocated path on success. * Return 0 if file was found and readable, -errno otherwise. */ static int get_real_path(const char *raw_path, const char *comp_dir, char **new_path) { const char *prefix = symbol_conf.source_prefix; if (!prefix) { if (raw_path[0] != '/' && comp_dir) /* If not an absolute path, try to use comp_dir */ prefix = comp_dir; else { if (access(raw_path, R_OK) == 0) { *new_path = strdup(raw_path); return 0; } else return -errno; } } *new_path = malloc((strlen(prefix) + strlen(raw_path) + 2)); if (!*new_path) return -ENOMEM; for (;;) { sprintf(*new_path, "%s/%s", prefix, raw_path); if (access(*new_path, R_OK) == 0) return 0; if (!symbol_conf.source_prefix) /* In case of searching comp_dir, don't retry */ return -errno; switch (errno) { case ENAMETOOLONG: case ENOENT: case EROFS: case EFAULT: raw_path = strchr(++raw_path, '/'); if (!raw_path) { free(*new_path); *new_path = NULL; return -ENOENT; } continue; default: free(*new_path); *new_path = NULL; return -errno; } } } #define LINEBUF_SIZE 256 #define NR_ADDITIONAL_LINES 2 static int show_one_line(FILE *fp, int l, bool skip, bool show_num) { char buf[LINEBUF_SIZE]; const char *color = PERF_COLOR_BLUE; if (fgets(buf, LINEBUF_SIZE, fp) == NULL) goto error; if (!skip) { if (show_num) fprintf(stdout, "%7d %s", l, buf); else color_fprintf(stdout, color, " %s", buf); } while (strlen(buf) == LINEBUF_SIZE - 1 && buf[LINEBUF_SIZE - 2] != '\n') { if (fgets(buf, LINEBUF_SIZE, fp) == NULL) goto error; if (!skip) { if (show_num) fprintf(stdout, "%s", buf); else color_fprintf(stdout, color, "%s", buf); } } return 0; error: if (feof(fp)) pr_warning("Source file is shorter than expected.\n"); else pr_warning("File read error: %s\n", strerror(errno)); return -1; } /* * Show line-range always requires debuginfo to find source file and * line number. */ int show_line_range(struct line_range *lr, const char *module) { int l = 1; struct line_node *ln; FILE *fp; int fd, ret; char *tmp; /* Search a line range */ ret = init_vmlinux(); if (ret < 0) return ret; fd = open_vmlinux(module); if (fd < 0) { pr_warning("Failed to open debuginfo file.\n"); return fd; } ret = find_line_range(fd, lr); close(fd); if (ret == 0) { pr_warning("Specified source line is not found.\n"); return -ENOENT; } else if (ret < 0) { pr_warning("Debuginfo analysis failed. (%d)\n", ret); return ret; } /* Convert source file path */ tmp = lr->path; ret = get_real_path(tmp, lr->comp_dir, &lr->path); free(tmp); /* Free old path */ if (ret < 0) { pr_warning("Failed to find source file. (%d)\n", ret); return ret; } setup_pager(); if (lr->function) fprintf(stdout, "<%s:%d>\n", lr->function, lr->start - lr->offset); else fprintf(stdout, "<%s:%d>\n", lr->path, lr->start); fp = fopen(lr->path, "r"); if (fp == NULL) { pr_warning("Failed to open %s: %s\n", lr->path, strerror(errno)); return -errno; } /* Skip to starting line number */ while (l < lr->start && ret >= 0) ret = show_one_line(fp, l++, true, false); if (ret < 0) goto end; list_for_each_entry(ln, &lr->line_list, list) { while (ln->line > l && ret >= 0) ret = show_one_line(fp, (l++) - lr->offset, false, false); if (ret >= 0) ret = show_one_line(fp, (l++) - lr->offset, false, true); if (ret < 0) goto end; } if (lr->end == INT_MAX) lr->end = l + NR_ADDITIONAL_LINES; while (l <= lr->end && !feof(fp) && ret >= 0) ret = show_one_line(fp, (l++) - lr->offset, false, false); end: fclose(fp); return ret; } static int show_available_vars_at(int fd, struct perf_probe_event *pev, int max_vls, bool externs) { char *buf; int ret, i; struct str_node *node; struct variable_list *vls = NULL, *vl; buf = synthesize_perf_probe_point(&pev->point); if (!buf) return -EINVAL; pr_debug("Searching variables at %s\n", buf); ret = find_available_vars_at(fd, pev, &vls, max_vls, externs); if (ret > 0) { /* Some variables were found */ fprintf(stdout, "Available variables at %s\n", buf); for (i = 0; i < ret; i++) { vl = &vls[i]; /* * A probe point might be converted to * several trace points. */ fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol, vl->point.offset); free(vl->point.symbol); if (vl->vars) { strlist__for_each(node, vl->vars) fprintf(stdout, "\t\t%s\n", node->s); strlist__delete(vl->vars); } else fprintf(stdout, "(No variables)\n"); } free(vls); } else pr_err("Failed to find variables at %s (%d)\n", buf, ret); free(buf); return ret; } /* Show available variables on given probe point */ int show_available_vars(struct perf_probe_event *pevs, int npevs, int max_vls, const char *module, bool externs) { int i, fd, ret = 0; ret = init_vmlinux(); if (ret < 0) return ret; fd = open_vmlinux(module); if (fd < 0) { pr_warning("Failed to open debug information file.\n"); return fd; } setup_pager(); for (i = 0; i < npevs && ret >= 0; i++) ret = show_available_vars_at(fd, &pevs[i], max_vls, externs); close(fd); return ret; } #else /* !DWARF_SUPPORT */ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp, struct perf_probe_point *pp) { struct symbol *sym; sym = __find_kernel_function_by_name(tp->symbol, NULL); if (!sym) { pr_err("Failed to find symbol %s in kernel.\n", tp->symbol); return -ENOENT; } pp->function = strdup(tp->symbol); if (pp->function == NULL) return -ENOMEM; pp->offset = tp->offset; pp->retprobe = tp->retprobe; return 0; } static int try_to_find_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event **tevs __unused, int max_tevs __unused, const char *mod __unused) { if (perf_probe_event_need_dwarf(pev)) { pr_warning("Debuginfo-analysis is not supported.\n"); return -ENOSYS; } return 0; } int show_line_range(struct line_range *lr __unused, const char *module __unused) { pr_warning("Debuginfo-analysis is not supported.\n"); return -ENOSYS; } int show_available_vars(struct perf_probe_event *pevs __unused, int npevs __unused, int max_vls __unused, const char *module __unused, bool externs __unused) { pr_warning("Debuginfo-analysis is not supported.\n"); return -ENOSYS; } #endif int parse_line_range_desc(const char *arg, struct line_range *lr) { const char *ptr; char *tmp; /* * * SRC:SLN[+NUM|-ELN] * FUNC[:SLN[+NUM|-ELN]] */ ptr = strchr(arg, ':'); if (ptr) { lr->start = (int)strtoul(ptr + 1, &tmp, 0); if (*tmp == '+') { lr->end = lr->start + (int)strtoul(tmp + 1, &tmp, 0); lr->end--; /* * Adjust the number of lines here. * If the number of lines == 1, the * the end of line should be equal to * the start of line. */ } else if (*tmp == '-') lr->end = (int)strtoul(tmp + 1, &tmp, 0); else lr->end = INT_MAX; pr_debug("Line range is %d to %d\n", lr->start, lr->end); if (lr->start > lr->end) { semantic_error("Start line must be smaller" " than end line.\n"); return -EINVAL; } if (*tmp != '\0') { semantic_error("Tailing with invalid character '%d'.\n", *tmp); return -EINVAL; } tmp = strndup(arg, (ptr - arg)); } else { tmp = strdup(arg); lr->end = INT_MAX; } if (tmp == NULL) return -ENOMEM; if (strchr(tmp, '.')) lr->file = tmp; else lr->function = tmp; return 0; } /* Check the name is good for event/group */ static bool check_event_name(const char *name) { if (!isalpha(*name) && *name != '_') return false; while (*++name != '\0') { if (!isalpha(*name) && !isdigit(*name) && *name != '_') return false; } return true; } /* Parse probepoint definition. */ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) { struct perf_probe_point *pp = &pev->point; char *ptr, *tmp; char c, nc = 0; /* * * perf probe [EVENT=]SRC[:LN|;PTN] * perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT] * * TODO:Group name support */ ptr = strpbrk(arg, ";=@+%"); if (ptr && *ptr == '=') { /* Event name */ *ptr = '\0'; tmp = ptr + 1; if (strchr(arg, ':')) { semantic_error("Group name is not supported yet.\n"); return -ENOTSUP; } if (!check_event_name(arg)) { semantic_error("%s is bad for event name -it must " "follow C symbol-naming rule.\n", arg); return -EINVAL; } pev->event = strdup(arg); if (pev->event == NULL) return -ENOMEM; pev->group = NULL; arg = tmp; } ptr = strpbrk(arg, ";:+@%"); if (ptr) { nc = *ptr; *ptr++ = '\0'; } tmp = strdup(arg); if (tmp == NULL) return -ENOMEM; /* Check arg is function or file and copy it */ if (strchr(tmp, '.')) /* File */ pp->file = tmp; else /* Function */ pp->function = tmp; /* Parse other options */ while (ptr) { arg = ptr; c = nc; if (c == ';') { /* Lazy pattern must be the last part */ pp->lazy_line = strdup(arg); if (pp->lazy_line == NULL) return -ENOMEM; break; } ptr = strpbrk(arg, ";:+@%"); if (ptr) { nc = *ptr; *ptr++ = '\0'; } switch (c) { case ':': /* Line number */ pp->line = strtoul(arg, &tmp, 0); if (*tmp != '\0') { semantic_error("There is non-digit char" " in line number.\n"); return -EINVAL; } break; case '+': /* Byte offset from a symbol */ pp->offset = strtoul(arg, &tmp, 0); if (*tmp != '\0') { semantic_error("There is non-digit character" " in offset.\n"); return -EINVAL; } break; case '@': /* File name */ if (pp->file) { semantic_error("SRC@SRC is not allowed.\n"); return -EINVAL; } pp->file = strdup(arg); if (pp->file == NULL) return -ENOMEM; break; case '%': /* Probe places */ if (strcmp(arg, "return") == 0) { pp->retprobe = 1; } else { /* Others not supported yet */ semantic_error("%%%s is not supported.\n", arg); return -ENOTSUP; } break; default: /* Buggy case */ pr_err("This program has a bug at %s:%d.\n", __FILE__, __LINE__); return -ENOTSUP; break; } } /* Exclusion check */ if (pp->lazy_line && pp->line) { semantic_error("Lazy pattern can't be used with" " line number.\n"); return -EINVAL; } if (pp->lazy_line && pp->offset) { semantic_error("Lazy pattern can't be used with offset.\n"); return -EINVAL; } if (pp->line && pp->offset) { semantic_error("Offset can't be used with line number.\n"); return -EINVAL; } if (!pp->line && !pp->lazy_line && pp->file && !pp->function) { semantic_error("File always requires line number or " "lazy pattern.\n"); return -EINVAL; } if (pp->offset && !pp->function) { semantic_error("Offset requires an entry function.\n"); return -EINVAL; } if (pp->retprobe && !pp->function) { semantic_error("Return probe requires an entry function.\n"); return -EINVAL; } if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) { semantic_error("Offset/Line/Lazy pattern can't be used with " "return probe.\n"); return -EINVAL; } pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n", pp->function, pp->file, pp->line, pp->offset, pp->retprobe, pp->lazy_line); return 0; } /* Parse perf-probe event argument */ static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg) { char *tmp, *goodname; struct perf_probe_arg_field **fieldp; pr_debug("parsing arg: %s into ", str); tmp = strchr(str, '='); if (tmp) { arg->name = strndup(str, tmp - str); if (arg->name == NULL) return -ENOMEM; pr_debug("name:%s ", arg->name); str = tmp + 1; } tmp = strchr(str, ':'); if (tmp) { /* Type setting */ *tmp = '\0'; arg->type = strdup(tmp + 1); if (arg->type == NULL) return -ENOMEM; pr_debug("type:%s ", arg->type); } tmp = strpbrk(str, "-.["); if (!is_c_varname(str) || !tmp) { /* A variable, register, symbol or special value */ arg->var = strdup(str); if (arg->var == NULL) return -ENOMEM; pr_debug("%s\n", arg->var); return 0; } /* Structure fields or array element */ arg->var = strndup(str, tmp - str); if (arg->var == NULL) return -ENOMEM; goodname = arg->var; pr_debug("%s, ", arg->var); fieldp = &arg->field; do { *fieldp = zalloc(sizeof(struct perf_probe_arg_field)); if (*fieldp == NULL) return -ENOMEM; if (*tmp == '[') { /* Array */ str = tmp; (*fieldp)->index = strtol(str + 1, &tmp, 0); (*fieldp)->ref = true; if (*tmp != ']' || tmp == str + 1) { semantic_error("Array index must be a" " number.\n"); return -EINVAL; } tmp++; if (*tmp == '\0') tmp = NULL; } else { /* Structure */ if (*tmp == '.') { str = tmp + 1; (*fieldp)->ref = false; } else if (tmp[1] == '>') { str = tmp + 2; (*fieldp)->ref = true; } else { semantic_error("Argument parse error: %s\n", str); return -EINVAL; } tmp = strpbrk(str, "-.["); } if (tmp) { (*fieldp)->name = strndup(str, tmp - str); if ((*fieldp)->name == NULL) return -ENOMEM; if (*str != '[') goodname = (*fieldp)->name; pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref); fieldp = &(*fieldp)->next; } } while (tmp); (*fieldp)->name = strdup(str); if ((*fieldp)->name == NULL) return -ENOMEM; if (*str != '[') goodname = (*fieldp)->name; pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref); /* If no name is specified, set the last field name (not array index)*/ if (!arg->name) { arg->name = strdup(goodname); if (arg->name == NULL) return -ENOMEM; } return 0; } /* Parse perf-probe event command */ int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev) { char **argv; int argc, i, ret = 0; argv = argv_split(cmd, &argc); if (!argv) { pr_debug("Failed to split arguments.\n"); return -ENOMEM; } if (argc - 1 > MAX_PROBE_ARGS) { semantic_error("Too many probe arguments (%d).\n", argc - 1); ret = -ERANGE; goto out; } /* Parse probe point */ ret = parse_perf_probe_point(argv[0], pev); if (ret < 0) goto out; /* Copy arguments and ensure return probe has no C argument */ pev->nargs = argc - 1; pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs); if (pev->args == NULL) { ret = -ENOMEM; goto out; } for (i = 0; i < pev->nargs && ret >= 0; i++) { ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]); if (ret >= 0 && is_c_varname(pev->args[i].var) && pev->point.retprobe) { semantic_error("You can't specify local variable for" " kretprobe.\n"); ret = -EINVAL; } } out: argv_free(argv); return ret; } /* Return true if this perf_probe_event requires debuginfo */ bool perf_probe_event_need_dwarf(struct perf_probe_event *pev) { int i; if (pev->point.file || pev->point.line || pev->point.lazy_line) return true; for (i = 0; i < pev->nargs; i++) if (is_c_varname(pev->args[i].var)) return true; return false; } /* Parse probe_events event into struct probe_point */ static int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev) { struct probe_trace_point *tp = &tev->point; char pr; char *p; int ret, i, argc; char **argv; pr_debug("Parsing probe_events: %s\n", cmd); argv = argv_split(cmd, &argc); if (!argv) { pr_debug("Failed to split arguments.\n"); return -ENOMEM; } if (argc < 2) { semantic_error("Too few probe arguments.\n"); ret = -ERANGE; goto out; } /* Scan event and group name. */ ret = sscanf(argv[0], "%c:%a[^/ \t]/%a[^ \t]", &pr, (float *)(void *)&tev->group, (float *)(void *)&tev->event); if (ret != 3) { semantic_error("Failed to parse event name: %s\n", argv[0]); ret = -EINVAL; goto out; } pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr); tp->retprobe = (pr == 'r'); /* Scan function name and offset */ ret = sscanf(argv[1], "%a[^+]+%lu", (float *)(void *)&tp->symbol, &tp->offset); if (ret == 1) tp->offset = 0; tev->nargs = argc - 2; tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs); if (tev->args == NULL) { ret = -ENOMEM; goto out; } for (i = 0; i < tev->nargs; i++) { p = strchr(argv[i + 2], '='); if (p) /* We don't need which register is assigned. */ *p++ = '\0'; else p = argv[i + 2]; tev->args[i].name = strdup(argv[i + 2]); /* TODO: parse regs and offset */ tev->args[i].value = strdup(p); if (tev->args[i].name == NULL || tev->args[i].value == NULL) { ret = -ENOMEM; goto out; } } ret = 0; out: argv_free(argv); return ret; } /* Compose only probe arg */ int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len) { struct perf_probe_arg_field *field = pa->field; int ret; char *tmp = buf; if (pa->name && pa->var) ret = e_snprintf(tmp, len, "%s=%s", pa->name, pa->var); else ret = e_snprintf(tmp, len, "%s", pa->name ? pa->name : pa->var); if (ret <= 0) goto error; tmp += ret; len -= ret; while (field) { if (field->name[0] == '[') ret = e_snprintf(tmp, len, "%s", field->name); else ret = e_snprintf(tmp, len, "%s%s", field->ref ? "->" : ".", field->name); if (ret <= 0) goto error; tmp += ret; len -= ret; field = field->next; } if (pa->type) { ret = e_snprintf(tmp, len, ":%s", pa->type); if (ret <= 0) goto error; tmp += ret; len -= ret; } return tmp - buf; error: pr_debug("Failed to synthesize perf probe argument: %s\n", strerror(-ret)); return ret; } /* Compose only probe point (not argument) */ static char *synthesize_perf_probe_point(struct perf_probe_point *pp) { char *buf, *tmp; char offs[32] = "", line[32] = "", file[32] = ""; int ret, len; buf = zalloc(MAX_CMDLEN); if (buf == NULL) { ret = -ENOMEM; goto error; } if (pp->offset) { ret = e_snprintf(offs, 32, "+%lu", pp->offset); if (ret <= 0) goto error; } if (pp->line) { ret = e_snprintf(line, 32, ":%d", pp->line); if (ret <= 0) goto error; } if (pp->file) { len = strlen(pp->file) - 31; if (len < 0) len = 0; tmp = strchr(pp->file + len, '/'); if (!tmp) tmp = pp->file + len; ret = e_snprintf(file, 32, "@%s", tmp + 1); if (ret <= 0) goto error; } if (pp->function) ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function, offs, pp->retprobe ? "%return" : "", line, file); else ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line); if (ret <= 0) goto error; return buf; error: pr_debug("Failed to synthesize perf probe point: %s\n", strerror(-ret)); if (buf) free(buf); return NULL; } #if 0 char *synthesize_perf_probe_command(struct perf_probe_event *pev) { char *buf; int i, len, ret; buf = synthesize_perf_probe_point(&pev->point); if (!buf) return NULL; len = strlen(buf); for (i = 0; i < pev->nargs; i++) { ret = e_snprintf(&buf[len], MAX_CMDLEN - len, " %s", pev->args[i].name); if (ret <= 0) { free(buf); return NULL; } len += ret; } return buf; } #endif static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref, char **buf, size_t *buflen, int depth) { int ret; if (ref->next) { depth = __synthesize_probe_trace_arg_ref(ref->next, buf, buflen, depth + 1); if (depth < 0) goto out; } ret = e_snprintf(*buf, *buflen, "%+ld(", ref->offset); if (ret < 0) depth = ret; else { *buf += ret; *buflen -= ret; } out: return depth; } static int synthesize_probe_trace_arg(struct probe_trace_arg *arg, char *buf, size_t buflen) { struct probe_trace_arg_ref *ref = arg->ref; int ret, depth = 0; char *tmp = buf; /* Argument name or separator */ if (arg->name) ret = e_snprintf(buf, buflen, " %s=", arg->name); else ret = e_snprintf(buf, buflen, " "); if (ret < 0) return ret; buf += ret; buflen -= ret; /* Special case: @XXX */ if (arg->value[0] == '@' && arg->ref) ref = ref->next; /* Dereferencing arguments */ if (ref) { depth = __synthesize_probe_trace_arg_ref(ref, &buf, &buflen, 1); if (depth < 0) return depth; } /* Print argument value */ if (arg->value[0] == '@' && arg->ref) ret = e_snprintf(buf, buflen, "%s%+ld", arg->value, arg->ref->offset); else ret = e_snprintf(buf, buflen, "%s", arg->value); if (ret < 0) return ret; buf += ret; buflen -= ret; /* Closing */ while (depth--) { ret = e_snprintf(buf, buflen, ")"); if (ret < 0) return ret; buf += ret; buflen -= ret; } /* Print argument type */ if (arg->type) { ret = e_snprintf(buf, buflen, ":%s", arg->type); if (ret <= 0) return ret; buf += ret; } return buf - tmp; } char *synthesize_probe_trace_command(struct probe_trace_event *tev) { struct probe_trace_point *tp = &tev->point; char *buf; int i, len, ret; buf = zalloc(MAX_CMDLEN); if (buf == NULL) return NULL; len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s+%lu", tp->retprobe ? 'r' : 'p', tev->group, tev->event, tp->symbol, tp->offset); if (len <= 0) goto error; for (i = 0; i < tev->nargs; i++) { ret = synthesize_probe_trace_arg(&tev->args[i], buf + len, MAX_CMDLEN - len); if (ret <= 0) goto error; len += ret; } return buf; error: free(buf); return NULL; } static int convert_to_perf_probe_event(struct probe_trace_event *tev, struct perf_probe_event *pev) { char buf[64] = ""; int i, ret; /* Convert event/group name */ pev->event = strdup(tev->event); pev->group = strdup(tev->group); if (pev->event == NULL || pev->group == NULL) return -ENOMEM; /* Convert trace_point to probe_point */ ret = kprobe_convert_to_perf_probe(&tev->point, &pev->point); if (ret < 0) return ret; /* Convert trace_arg to probe_arg */ pev->nargs = tev->nargs; pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs); if (pev->args == NULL) return -ENOMEM; for (i = 0; i < tev->nargs && ret >= 0; i++) { if (tev->args[i].name) pev->args[i].name = strdup(tev->args[i].name); else { ret = synthesize_probe_trace_arg(&tev->args[i], buf, 64); pev->args[i].name = strdup(buf); } if (pev->args[i].name == NULL && ret >= 0) ret = -ENOMEM; } if (ret < 0) clear_perf_probe_event(pev); return ret; } void clear_perf_probe_event(struct perf_probe_event *pev) { struct perf_probe_point *pp = &pev->point; struct perf_probe_arg_field *field, *next; int i; if (pev->event) free(pev->event); if (pev->group) free(pev->group); if (pp->file) free(pp->file); if (pp->function) free(pp->function); if (pp->lazy_line) free(pp->lazy_line); for (i = 0; i < pev->nargs; i++) { if (pev->args[i].name) free(pev->args[i].name); if (pev->args[i].var) free(pev->args[i].var); if (pev->args[i].type) free(pev->args[i].type); field = pev->args[i].field; while (field) { next = field->next; if (field->name) free(field->name); free(field); field = next; } } if (pev->args) free(pev->args); memset(pev, 0, sizeof(*pev)); } static void clear_probe_trace_event(struct probe_trace_event *tev) { struct probe_trace_arg_ref *ref, *next; int i; if (tev->event) free(tev->event); if (tev->group) free(tev->group); if (tev->point.symbol) free(tev->point.symbol); for (i = 0; i < tev->nargs; i++) { if (tev->args[i].name) free(tev->args[i].name); if (tev->args[i].value) free(tev->args[i].value); if (tev->args[i].type) free(tev->args[i].type); ref = tev->args[i].ref; while (ref) { next = ref->next; free(ref); ref = next; } } if (tev->args) free(tev->args); memset(tev, 0, sizeof(*tev)); } static int open_kprobe_events(bool readwrite) { char buf[PATH_MAX]; const char *__debugfs; int ret; __debugfs = debugfs_find_mountpoint(); if (__debugfs == NULL) { pr_warning("Debugfs is not mounted.\n"); return -ENOENT; } ret = e_snprintf(buf, PATH_MAX, "%stracing/kprobe_events", __debugfs); if (ret >= 0) { pr_debug("Opening %s write=%d\n", buf, readwrite); if (readwrite && !probe_event_dry_run) ret = open(buf, O_RDWR, O_APPEND); else ret = open(buf, O_RDONLY, 0); } if (ret < 0) { if (errno == ENOENT) pr_warning("kprobe_events file does not exist - please" " rebuild kernel with CONFIG_KPROBE_EVENT.\n"); else pr_warning("Failed to open kprobe_events file: %s\n", strerror(errno)); } return ret; } /* Get raw string list of current kprobe_events */ static struct strlist *get_probe_trace_command_rawlist(int fd) { int ret, idx; FILE *fp; char buf[MAX_CMDLEN]; char *p; struct strlist *sl; sl = strlist__new(true, NULL); fp = fdopen(dup(fd), "r"); while (!feof(fp)) { p = fgets(buf, MAX_CMDLEN, fp); if (!p) break; idx = strlen(p) - 1; if (p[idx] == '\n') p[idx] = '\0'; ret = strlist__add(sl, buf); if (ret < 0) { pr_debug("strlist__add failed: %s\n", strerror(-ret)); strlist__delete(sl); return NULL; } } fclose(fp); return sl; } /* Show an event */ static int show_perf_probe_event(struct perf_probe_event *pev) { int i, ret; char buf[128]; char *place; /* Synthesize only event probe point */ place = synthesize_perf_probe_point(&pev->point); if (!place) return -EINVAL; ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event); if (ret < 0) return ret; printf(" %-20s (on %s", buf, place); if (pev->nargs > 0) { printf(" with"); for (i = 0; i < pev->nargs; i++) { ret = synthesize_perf_probe_arg(&pev->args[i], buf, 128); if (ret < 0) break; printf(" %s", buf); } } printf(")\n"); free(place); return ret; } /* List up current perf-probe events */ int show_perf_probe_events(void) { int fd, ret; struct probe_trace_event tev; struct perf_probe_event pev; struct strlist *rawlist; struct str_node *ent; setup_pager(); ret = init_vmlinux(); if (ret < 0) return ret; memset(&tev, 0, sizeof(tev)); memset(&pev, 0, sizeof(pev)); fd = open_kprobe_events(false); if (fd < 0) return fd; rawlist = get_probe_trace_command_rawlist(fd); close(fd); if (!rawlist) return -ENOENT; strlist__for_each(ent, rawlist) { ret = parse_probe_trace_command(ent->s, &tev); if (ret >= 0) { ret = convert_to_perf_probe_event(&tev, &pev); if (ret >= 0) ret = show_perf_probe_event(&pev); } clear_perf_probe_event(&pev); clear_probe_trace_event(&tev); if (ret < 0) break; } strlist__delete(rawlist); return ret; } /* Get current perf-probe event names */ static struct strlist *get_probe_trace_event_names(int fd, bool include_group) { char buf[128]; struct strlist *sl, *rawlist; struct str_node *ent; struct probe_trace_event tev; int ret = 0; memset(&tev, 0, sizeof(tev)); rawlist = get_probe_trace_command_rawlist(fd); sl = strlist__new(true, NULL); strlist__for_each(ent, rawlist) { ret = parse_probe_trace_command(ent->s, &tev); if (ret < 0) break; if (include_group) { ret = e_snprintf(buf, 128, "%s:%s", tev.group, tev.event); if (ret >= 0) ret = strlist__add(sl, buf); } else ret = strlist__add(sl, tev.event); clear_probe_trace_event(&tev); if (ret < 0) break; } strlist__delete(rawlist); if (ret < 0) { strlist__delete(sl); return NULL; } return sl; } static int write_probe_trace_event(int fd, struct probe_trace_event *tev) { int ret = 0; char *buf = synthesize_probe_trace_command(tev); if (!buf) { pr_debug("Failed to synthesize probe trace event.\n"); return -EINVAL; } pr_debug("Writing event: %s\n", buf); if (!probe_event_dry_run) { ret = write(fd, buf, strlen(buf)); if (ret <= 0) pr_warning("Failed to write event: %s\n", strerror(errno)); } free(buf); return ret; } static int get_new_event_name(char *buf, size_t len, const char *base, struct strlist *namelist, bool allow_suffix) { int i, ret; /* Try no suffix */ ret = e_snprintf(buf, len, "%s", base); if (ret < 0) { pr_debug("snprintf() failed: %s\n", strerror(-ret)); return ret; } if (!strlist__has_entry(namelist, buf)) return 0; if (!allow_suffix) { pr_warning("Error: event \"%s\" already exists. " "(Use -f to force duplicates.)\n", base); return -EEXIST; } /* Try to add suffix */ for (i = 1; i < MAX_EVENT_INDEX; i++) { ret = e_snprintf(buf, len, "%s_%d", base, i); if (ret < 0) { pr_debug("snprintf() failed: %s\n", strerror(-ret)); return ret; } if (!strlist__has_entry(namelist, buf)) break; } if (i == MAX_EVENT_INDEX) { pr_warning("Too many events are on the same function.\n"); ret = -ERANGE; } return ret; } static int __add_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event *tevs, int ntevs, bool allow_suffix) { int i, fd, ret; struct probe_trace_event *tev = NULL; char buf[64]; const char *event, *group; struct strlist *namelist; fd = open_kprobe_events(true); if (fd < 0) return fd; /* Get current event names */ namelist = get_probe_trace_event_names(fd, false); if (!namelist) { pr_debug("Failed to get current event list.\n"); return -EIO; } ret = 0; printf("Add new event%s\n", (ntevs > 1) ? "s:" : ":"); for (i = 0; i < ntevs; i++) { tev = &tevs[i]; if (pev->event) event = pev->event; else if (pev->point.function) event = pev->point.function; else event = tev->point.symbol; if (pev->group) group = pev->group; else group = PERFPROBE_GROUP; /* Get an unused new event name */ ret = get_new_event_name(buf, 64, event, namelist, allow_suffix); if (ret < 0) break; event = buf; tev->event = strdup(event); tev->group = strdup(group); if (tev->event == NULL || tev->group == NULL) { ret = -ENOMEM; break; } ret = write_probe_trace_event(fd, tev); if (ret < 0) break; /* Add added event name to namelist */ strlist__add(namelist, event); /* Trick here - save current event/group */ event = pev->event; group = pev->group; pev->event = tev->event; pev->group = tev->group; show_perf_probe_event(pev); /* Trick here - restore current event/group */ pev->event = (char *)event; pev->group = (char *)group; /* * Probes after the first probe which comes from same * user input are always allowed to add suffix, because * there might be several addresses corresponding to * one code line. */ allow_suffix = true; } if (ret >= 0) { /* Show how to use the event. */ printf("\nYou can now use it on all perf tools, such as:\n\n"); printf("\tperf record -e %s:%s -aR sleep 1\n\n", tev->group, tev->event); } strlist__delete(namelist); close(fd); return ret; } static int convert_to_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event **tevs, int max_tevs, const char *module) { struct symbol *sym; int ret = 0, i; struct probe_trace_event *tev; /* Convert perf_probe_event with debuginfo */ ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, module); if (ret != 0) return ret; /* Allocate trace event buffer */ tev = *tevs = zalloc(sizeof(struct probe_trace_event)); if (tev == NULL) return -ENOMEM; /* Copy parameters */ tev->point.symbol = strdup(pev->point.function); if (tev->point.symbol == NULL) { ret = -ENOMEM; goto error; } tev->point.offset = pev->point.offset; tev->point.retprobe = pev->point.retprobe; tev->nargs = pev->nargs; if (tev->nargs) { tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs); if (tev->args == NULL) { ret = -ENOMEM; goto error; } for (i = 0; i < tev->nargs; i++) { if (pev->args[i].name) { tev->args[i].name = strdup(pev->args[i].name); if (tev->args[i].name == NULL) { ret = -ENOMEM; goto error; } } tev->args[i].value = strdup(pev->args[i].var); if (tev->args[i].value == NULL) { ret = -ENOMEM; goto error; } if (pev->args[i].type) { tev->args[i].type = strdup(pev->args[i].type); if (tev->args[i].type == NULL) { ret = -ENOMEM; goto error; } } } } /* Currently just checking function name from symbol map */ sym = __find_kernel_function_by_name(tev->point.symbol, NULL); if (!sym) { pr_warning("Kernel symbol \'%s\' not found.\n", tev->point.symbol); ret = -ENOENT; goto error; } return 1; error: clear_probe_trace_event(tev); free(tev); *tevs = NULL; return ret; } struct __event_package { struct perf_probe_event *pev; struct probe_trace_event *tevs; int ntevs; }; int add_perf_probe_events(struct perf_probe_event *pevs, int npevs, int max_tevs, const char *module, bool force_add) { int i, j, ret; struct __event_package *pkgs; pkgs = zalloc(sizeof(struct __event_package) * npevs); if (pkgs == NULL) return -ENOMEM; /* Init vmlinux path */ ret = init_vmlinux(); if (ret < 0) { free(pkgs); return ret; } /* Loop 1: convert all events */ for (i = 0; i < npevs; i++) { pkgs[i].pev = &pevs[i]; /* Convert with or without debuginfo */ ret = convert_to_probe_trace_events(pkgs[i].pev, &pkgs[i].tevs, max_tevs, module); if (ret < 0) goto end; pkgs[i].ntevs = ret; } /* Loop 2: add all events */ for (i = 0; i < npevs && ret >= 0; i++) ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs, pkgs[i].ntevs, force_add); end: /* Loop 3: cleanup and free trace events */ for (i = 0; i < npevs; i++) { for (j = 0; j < pkgs[i].ntevs; j++) clear_probe_trace_event(&pkgs[i].tevs[j]); free(pkgs[i].tevs); } free(pkgs); return ret; } static int __del_trace_probe_event(int fd, struct str_node *ent) { char *p; char buf[128]; int ret; /* Convert from perf-probe event to trace-probe event */ ret = e_snprintf(buf, 128, "-:%s", ent->s); if (ret < 0) goto error; p = strchr(buf + 2, ':'); if (!p) { pr_debug("Internal error: %s should have ':' but not.\n", ent->s); ret = -ENOTSUP; goto error; } *p = '/'; pr_debug("Writing event: %s\n", buf); ret = write(fd, buf, strlen(buf)); if (ret < 0) goto error; printf("Remove event: %s\n", ent->s); return 0; error: pr_warning("Failed to delete event: %s\n", strerror(-ret)); return ret; } static int del_trace_probe_event(int fd, const char *group, const char *event, struct strlist *namelist) { char buf[128]; struct str_node *ent, *n; int found = 0, ret = 0; ret = e_snprintf(buf, 128, "%s:%s", group, event); if (ret < 0) { pr_err("Failed to copy event.\n"); return ret; } if (strpbrk(buf, "*?")) { /* Glob-exp */ strlist__for_each_safe(ent, n, namelist) if (strglobmatch(ent->s, buf)) { found++; ret = __del_trace_probe_event(fd, ent); if (ret < 0) break; strlist__remove(namelist, ent); } } else { ent = strlist__find(namelist, buf); if (ent) { found++; ret = __del_trace_probe_event(fd, ent); if (ret >= 0) strlist__remove(namelist, ent); } } if (found == 0 && ret >= 0) pr_info("Info: Event \"%s\" does not exist.\n", buf); return ret; } int del_perf_probe_events(struct strlist *dellist) { int fd, ret = 0; const char *group, *event; char *p, *str; struct str_node *ent; struct strlist *namelist; fd = open_kprobe_events(true); if (fd < 0) return fd; /* Get current event names */ namelist = get_probe_trace_event_names(fd, true); if (namelist == NULL) return -EINVAL; strlist__for_each(ent, dellist) { str = strdup(ent->s); if (str == NULL) { ret = -ENOMEM; break; } pr_debug("Parsing: %s\n", str); p = strchr(str, ':'); if (p) { group = str; *p = '\0'; event = p + 1; } else { group = "*"; event = str; } pr_debug("Group: %s, Event: %s\n", group, event); ret = del_trace_probe_event(fd, group, event, namelist); free(str); if (ret < 0) break; } strlist__delete(namelist); close(fd); return ret; }