/* * 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. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include "util.h" #include "event.h" #include "strlist.h" #include "debug.h" #include "cache.h" #include "color.h" #include "symbol.h" #include "thread.h" #include #include #include "trace-event.h" /* For __maybe_unused */ #include "probe-event.h" #include "probe-finder.h" #include "session.h" #define MAX_CMDLEN 256 #define PERFPROBE_GROUP "probe" bool probe_event_dry_run; /* Dry run flag */ struct probe_conf probe_conf; #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 void clear_probe_trace_event(struct probe_trace_event *tev); static struct machine *host_machine; /* Initialize symbol maps and path of vmlinux/modules */ static int init_symbol_maps(bool user_only) { int ret; symbol_conf.sort_by_name = true; symbol_conf.allow_aliases = true; ret = symbol__init(NULL); if (ret < 0) { pr_debug("Failed to init symbol map.\n"); goto out; } if (host_machine || user_only) /* already initialized */ return 0; if (symbol_conf.vmlinux_name) pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name); host_machine = machine__new_host(); if (!host_machine) { pr_debug("machine__new_host() failed.\n"); symbol__exit(); ret = -1; } out: if (ret < 0) pr_warning("Failed to init vmlinux path.\n"); return ret; } static void exit_symbol_maps(void) { if (host_machine) { machine__delete(host_machine); host_machine = NULL; } symbol__exit(); } static struct symbol *__find_kernel_function_by_name(const char *name, struct map **mapp) { return machine__find_kernel_function_by_name(host_machine, name, mapp, NULL); } static struct symbol *__find_kernel_function(u64 addr, struct map **mapp) { return machine__find_kernel_function(host_machine, addr, mapp, NULL); } static struct ref_reloc_sym *kernel_get_ref_reloc_sym(void) { /* kmap->ref_reloc_sym should be set if host_machine is initialized */ struct kmap *kmap; if (map__load(host_machine->vmlinux_maps[MAP__FUNCTION], NULL) < 0) return NULL; kmap = map__kmap(host_machine->vmlinux_maps[MAP__FUNCTION]); if (!kmap) return NULL; return kmap->ref_reloc_sym; } static u64 kernel_get_symbol_address_by_name(const char *name, bool reloc) { struct ref_reloc_sym *reloc_sym; struct symbol *sym; struct map *map; /* ref_reloc_sym is just a label. Need a special fix*/ reloc_sym = kernel_get_ref_reloc_sym(); if (reloc_sym && strcmp(name, reloc_sym->name) == 0) return (reloc) ? reloc_sym->addr : reloc_sym->unrelocated_addr; else { sym = __find_kernel_function_by_name(name, &map); if (sym) return map->unmap_ip(map, sym->start) - ((reloc) ? 0 : map->reloc); } return 0; } static struct map *kernel_get_module_map(const char *module) { struct map_groups *grp = &host_machine->kmaps; struct rb_root *maps = &grp->maps[MAP__FUNCTION]; struct map *pos; /* A file path -- this is an offline module */ if (module && strchr(module, '/')) return machine__new_module(host_machine, 0, module); if (!module) module = "kernel"; for (pos = maps__first(maps); pos; pos = map__next(pos)) { if (strncmp(pos->dso->short_name + 1, module, pos->dso->short_name_len - 2) == 0) { return pos; } } return NULL; } static struct map *get_target_map(const char *target, bool user) { /* Init maps of given executable or kernel */ if (user) return dso__new_map(target); else return kernel_get_module_map(target); } static void put_target_map(struct map *map, bool user) { if (map && user) { /* Only the user map needs to be released */ map__delete(map); } } static int kernel_get_module_dso(const char *module, struct dso **pdso) { struct dso *dso; struct map *map; const char *vmlinux_name; int ret = 0; if (module) { list_for_each_entry(dso, &host_machine->kernel_dsos.head, 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 -ENOENT; } map = host_machine->vmlinux_maps[MAP__FUNCTION]; dso = map->dso; vmlinux_name = symbol_conf.vmlinux_name; dso->load_errno = 0; if (vmlinux_name) ret = dso__load_vmlinux(dso, map, vmlinux_name, false, NULL); else ret = dso__load_vmlinux_path(dso, map, NULL); found: *pdso = dso; return ret; } static int convert_exec_to_group(const char *exec, char **result) { char *ptr1, *ptr2, *exec_copy; char buf[64]; int ret; exec_copy = strdup(exec); if (!exec_copy) return -ENOMEM; ptr1 = basename(exec_copy); if (!ptr1) { ret = -EINVAL; goto out; } ptr2 = strpbrk(ptr1, "-._"); if (ptr2) *ptr2 = '\0'; ret = e_snprintf(buf, 64, "%s_%s", PERFPROBE_GROUP, ptr1); if (ret < 0) goto out; *result = strdup(buf); ret = *result ? 0 : -ENOMEM; out: free(exec_copy); return ret; } static void clear_perf_probe_point(struct perf_probe_point *pp) { free(pp->file); free(pp->function); free(pp->lazy_line); } static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs) { int i; for (i = 0; i < ntevs; i++) clear_probe_trace_event(tevs + i); } #ifdef HAVE_DWARF_SUPPORT /* * Some binaries like glibc have special symbols which are on the symbol * table, but not in the debuginfo. If we can find the address of the * symbol from map, we can translate the address back to the probe point. */ static int find_alternative_probe_point(struct debuginfo *dinfo, struct perf_probe_point *pp, struct perf_probe_point *result, const char *target, bool uprobes) { struct map *map = NULL; struct symbol *sym; u64 address = 0; int ret = -ENOENT; /* This can work only for function-name based one */ if (!pp->function || pp->file) return -ENOTSUP; map = get_target_map(target, uprobes); if (!map) return -EINVAL; /* Find the address of given function */ map__for_each_symbol_by_name(map, pp->function, sym) { if (uprobes) address = sym->start; else address = map->unmap_ip(map, sym->start); break; } if (!address) { ret = -ENOENT; goto out; } pr_debug("Symbol %s address found : %" PRIx64 "\n", pp->function, address); ret = debuginfo__find_probe_point(dinfo, (unsigned long)address, result); if (ret <= 0) ret = (!ret) ? -ENOENT : ret; else { result->offset += pp->offset; result->line += pp->line; result->retprobe = pp->retprobe; ret = 0; } out: put_target_map(map, uprobes); return ret; } static int get_alternative_probe_event(struct debuginfo *dinfo, struct perf_probe_event *pev, struct perf_probe_point *tmp) { int ret; memcpy(tmp, &pev->point, sizeof(*tmp)); memset(&pev->point, 0, sizeof(pev->point)); ret = find_alternative_probe_point(dinfo, tmp, &pev->point, pev->target, pev->uprobes); if (ret < 0) memcpy(&pev->point, tmp, sizeof(*tmp)); return ret; } static int get_alternative_line_range(struct debuginfo *dinfo, struct line_range *lr, const char *target, bool user) { struct perf_probe_point pp = { .function = lr->function, .file = lr->file, .line = lr->start }; struct perf_probe_point result; int ret, len = 0; memset(&result, 0, sizeof(result)); if (lr->end != INT_MAX) len = lr->end - lr->start; ret = find_alternative_probe_point(dinfo, &pp, &result, target, user); if (!ret) { lr->function = result.function; lr->file = result.file; lr->start = result.line; if (lr->end != INT_MAX) lr->end = lr->start + len; clear_perf_probe_point(&pp); } return ret; } /* Open new debuginfo of given module */ static struct debuginfo *open_debuginfo(const char *module, bool silent) { const char *path = module; char reason[STRERR_BUFSIZE]; struct debuginfo *ret = NULL; struct dso *dso = NULL; int err; if (!module || !strchr(module, '/')) { err = kernel_get_module_dso(module, &dso); if (err < 0) { if (!dso || dso->load_errno == 0) { if (!strerror_r(-err, reason, STRERR_BUFSIZE)) strcpy(reason, "(unknown)"); } else dso__strerror_load(dso, reason, STRERR_BUFSIZE); if (!silent) pr_err("Failed to find the path for %s: %s\n", module ?: "kernel", reason); return NULL; } path = dso->long_name; } ret = debuginfo__new(path); if (!ret && !silent) { pr_warning("The %s file has no debug information.\n", path); if (!module || !strtailcmp(path, ".ko")) pr_warning("Rebuild with CONFIG_DEBUG_INFO=y, "); else pr_warning("Rebuild with -g, "); pr_warning("or install an appropriate debuginfo package.\n"); } return ret; } static int get_text_start_address(const char *exec, unsigned long *address) { Elf *elf; GElf_Ehdr ehdr; GElf_Shdr shdr; int fd, ret = -ENOENT; fd = open(exec, O_RDONLY); if (fd < 0) return -errno; elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); if (elf == NULL) return -EINVAL; if (gelf_getehdr(elf, &ehdr) == NULL) goto out; if (!elf_section_by_name(elf, &ehdr, &shdr, ".text", NULL)) goto out; *address = shdr.sh_addr - shdr.sh_offset; ret = 0; out: elf_end(elf); return ret; } /* * Convert trace point to probe point with debuginfo */ static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp, struct perf_probe_point *pp, bool is_kprobe) { struct debuginfo *dinfo = NULL; unsigned long stext = 0; u64 addr = tp->address; int ret = -ENOENT; /* convert the address to dwarf address */ if (!is_kprobe) { if (!addr) { ret = -EINVAL; goto error; } ret = get_text_start_address(tp->module, &stext); if (ret < 0) goto error; addr += stext; } else { addr = kernel_get_symbol_address_by_name(tp->symbol, false); if (addr == 0) goto error; addr += tp->offset; } pr_debug("try to find information at %" PRIx64 " in %s\n", addr, tp->module ? : "kernel"); dinfo = open_debuginfo(tp->module, verbose == 0); if (dinfo) { ret = debuginfo__find_probe_point(dinfo, (unsigned long)addr, pp); debuginfo__delete(dinfo); } else ret = -ENOENT; if (ret > 0) { pp->retprobe = tp->retprobe; return 0; } error: pr_debug("Failed to find corresponding probes from debuginfo.\n"); return ret ? : -ENOENT; } static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs, int ntevs, const char *exec) { int i, ret = 0; unsigned long stext = 0; if (!exec) return 0; ret = get_text_start_address(exec, &stext); if (ret < 0) return ret; for (i = 0; i < ntevs && ret >= 0; i++) { /* point.address is the addres of point.symbol + point.offset */ tevs[i].point.address -= stext; tevs[i].point.module = strdup(exec); if (!tevs[i].point.module) { ret = -ENOMEM; break; } tevs[i].uprobes = true; } return ret; } static int add_module_to_probe_trace_events(struct probe_trace_event *tevs, int ntevs, const char *module) { int i, ret = 0; char *tmp; if (!module) return 0; tmp = strrchr(module, '/'); if (tmp) { /* This is a module path -- get the module name */ module = strdup(tmp + 1); if (!module) return -ENOMEM; tmp = strchr(module, '.'); if (tmp) *tmp = '\0'; tmp = (char *)module; /* For free() */ } for (i = 0; i < ntevs; i++) { tevs[i].point.module = strdup(module); if (!tevs[i].point.module) { ret = -ENOMEM; break; } } free(tmp); return ret; } /* Post processing the probe events */ static int post_process_probe_trace_events(struct probe_trace_event *tevs, int ntevs, const char *module, bool uprobe) { struct ref_reloc_sym *reloc_sym; u64 etext_addr; char *tmp; int i, skipped = 0; if (uprobe) return add_exec_to_probe_trace_events(tevs, ntevs, module); /* Note that currently ref_reloc_sym based probe is not for drivers */ if (module) return add_module_to_probe_trace_events(tevs, ntevs, module); reloc_sym = kernel_get_ref_reloc_sym(); if (!reloc_sym) { pr_warning("Relocated base symbol is not found!\n"); return -EINVAL; } /* Get the address of _etext for checking non-probable text symbol */ etext_addr = kernel_get_symbol_address_by_name("_etext", false); for (i = 0; i < ntevs; i++) { if (tevs[i].point.address && !tevs[i].point.retprobe) { /* If we found a wrong one, mark it by NULL symbol */ if (etext_addr < tevs[i].point.address) { pr_warning("%s+%lu is out of .text, skip it.\n", tevs[i].point.symbol, tevs[i].point.offset); tmp = NULL; skipped++; } else { tmp = strdup(reloc_sym->name); if (!tmp) return -ENOMEM; } /* If we have no realname, use symbol for it */ if (!tevs[i].point.realname) tevs[i].point.realname = tevs[i].point.symbol; else free(tevs[i].point.symbol); tevs[i].point.symbol = tmp; tevs[i].point.offset = tevs[i].point.address - reloc_sym->unrelocated_addr; } } return skipped; } /* 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) { bool need_dwarf = perf_probe_event_need_dwarf(pev); struct perf_probe_point tmp; struct debuginfo *dinfo; int ntevs, ret = 0; dinfo = open_debuginfo(pev->target, !need_dwarf); if (!dinfo) { if (need_dwarf) return -ENOENT; pr_debug("Could not open debuginfo. Try to use symbols.\n"); return 0; } pr_debug("Try to find probe point from debuginfo.\n"); /* Searching trace events corresponding to a probe event */ ntevs = debuginfo__find_trace_events(dinfo, pev, tevs); if (ntevs == 0) { /* Not found, retry with an alternative */ ret = get_alternative_probe_event(dinfo, pev, &tmp); if (!ret) { ntevs = debuginfo__find_trace_events(dinfo, pev, tevs); /* * Write back to the original probe_event for * setting appropriate (user given) event name */ clear_perf_probe_point(&pev->point); memcpy(&pev->point, &tmp, sizeof(tmp)); } } debuginfo__delete(dinfo); if (ntevs > 0) { /* Succeeded to find trace events */ pr_debug("Found %d probe_trace_events.\n", ntevs); ret = post_process_probe_trace_events(*tevs, ntevs, pev->target, pev->uprobes); if (ret < 0 || ret == ntevs) { clear_probe_trace_events(*tevs, ntevs); zfree(tevs); } if (ret != ntevs) return ret < 0 ? ret : ntevs; ntevs = 0; /* Fall through */ } 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; } #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], sbuf[STRERR_BUFSIZE]; const char *color = show_num ? "" : PERF_COLOR_BLUE; const char *prefix = NULL; do { if (fgets(buf, LINEBUF_SIZE, fp) == NULL) goto error; if (skip) continue; if (!prefix) { prefix = show_num ? "%7d " : " "; color_fprintf(stdout, color, prefix, l); } color_fprintf(stdout, color, "%s", buf); } while (strchr(buf, '\n') == NULL); return 1; error: if (ferror(fp)) { pr_warning("File read error: %s\n", strerror_r(errno, sbuf, sizeof(sbuf))); return -1; } return 0; } static int _show_one_line(FILE *fp, int l, bool skip, bool show_num) { int rv = __show_one_line(fp, l, skip, show_num); if (rv == 0) { pr_warning("Source file is shorter than expected.\n"); rv = -1; } return rv; } #define show_one_line_with_num(f,l) _show_one_line(f,l,false,true) #define show_one_line(f,l) _show_one_line(f,l,false,false) #define skip_one_line(f,l) _show_one_line(f,l,true,false) #define show_one_line_or_eof(f,l) __show_one_line(f,l,false,false) /* * Show line-range always requires debuginfo to find source file and * line number. */ static int __show_line_range(struct line_range *lr, const char *module, bool user) { int l = 1; struct int_node *ln; struct debuginfo *dinfo; FILE *fp; int ret; char *tmp; char sbuf[STRERR_BUFSIZE]; /* Search a line range */ dinfo = open_debuginfo(module, false); if (!dinfo) return -ENOENT; ret = debuginfo__find_line_range(dinfo, lr); if (!ret) { /* Not found, retry with an alternative */ ret = get_alternative_line_range(dinfo, lr, module, user); if (!ret) ret = debuginfo__find_line_range(dinfo, lr); } debuginfo__delete(dinfo); if (ret == 0 || ret == -ENOENT) { pr_warning("Specified source line is not found.\n"); return -ENOENT; } else if (ret < 0) { pr_warning("Debuginfo analysis failed.\n"); return ret; } /* Convert source file path */ tmp = lr->path; ret = get_real_path(tmp, lr->comp_dir, &lr->path); /* Free old path when new path is assigned */ if (tmp != lr->path) free(tmp); if (ret < 0) { pr_warning("Failed to find source file path.\n"); return ret; } setup_pager(); if (lr->function) fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path, 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_r(errno, sbuf, sizeof(sbuf))); return -errno; } /* Skip to starting line number */ while (l < lr->start) { ret = skip_one_line(fp, l++); if (ret < 0) goto end; } intlist__for_each(ln, lr->line_list) { for (; ln->i > l; l++) { ret = show_one_line(fp, l - lr->offset); if (ret < 0) goto end; } ret = show_one_line_with_num(fp, l++ - lr->offset); if (ret < 0) goto end; } if (lr->end == INT_MAX) lr->end = l + NR_ADDITIONAL_LINES; while (l <= lr->end) { ret = show_one_line_or_eof(fp, l++ - lr->offset); if (ret <= 0) break; } end: fclose(fp); return ret; } int show_line_range(struct line_range *lr, const char *module, bool user) { int ret; ret = init_symbol_maps(user); if (ret < 0) return ret; ret = __show_line_range(lr, module, user); exit_symbol_maps(); return ret; } static int show_available_vars_at(struct debuginfo *dinfo, struct perf_probe_event *pev, struct strfilter *_filter) { char *buf; int ret, i, nvars; struct str_node *node; struct variable_list *vls = NULL, *vl; struct perf_probe_point tmp; const char *var; buf = synthesize_perf_probe_point(&pev->point); if (!buf) return -EINVAL; pr_debug("Searching variables at %s\n", buf); ret = debuginfo__find_available_vars_at(dinfo, pev, &vls); if (!ret) { /* Not found, retry with an alternative */ ret = get_alternative_probe_event(dinfo, pev, &tmp); if (!ret) { ret = debuginfo__find_available_vars_at(dinfo, pev, &vls); /* Release the old probe_point */ clear_perf_probe_point(&tmp); } } if (ret <= 0) { if (ret == 0 || ret == -ENOENT) { pr_err("Failed to find the address of %s\n", buf); ret = -ENOENT; } else pr_warning("Debuginfo analysis failed.\n"); goto end; } /* Some variables are 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); zfree(&vl->point.symbol); nvars = 0; if (vl->vars) { strlist__for_each(node, vl->vars) { var = strchr(node->s, '\t') + 1; if (strfilter__compare(_filter, var)) { fprintf(stdout, "\t\t%s\n", node->s); nvars++; } } strlist__delete(vl->vars); } if (nvars == 0) fprintf(stdout, "\t\t(No matched variables)\n"); } free(vls); end: free(buf); return ret; } /* Show available variables on given probe point */ int show_available_vars(struct perf_probe_event *pevs, int npevs, struct strfilter *_filter) { int i, ret = 0; struct debuginfo *dinfo; ret = init_symbol_maps(pevs->uprobes); if (ret < 0) return ret; dinfo = open_debuginfo(pevs->target, false); if (!dinfo) { ret = -ENOENT; goto out; } setup_pager(); for (i = 0; i < npevs && ret >= 0; i++) ret = show_available_vars_at(dinfo, &pevs[i], _filter); debuginfo__delete(dinfo); out: exit_symbol_maps(); return ret; } #else /* !HAVE_DWARF_SUPPORT */ static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp __maybe_unused, struct perf_probe_point *pp __maybe_unused, bool is_kprobe __maybe_unused) { return -ENOSYS; } static int try_to_find_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event **tevs __maybe_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 __maybe_unused, const char *module __maybe_unused, bool user __maybe_unused) { pr_warning("Debuginfo-analysis is not supported.\n"); return -ENOSYS; } int show_available_vars(struct perf_probe_event *pevs __maybe_unused, int npevs __maybe_unused, struct strfilter *filter __maybe_unused) { pr_warning("Debuginfo-analysis is not supported.\n"); return -ENOSYS; } #endif void line_range__clear(struct line_range *lr) { free(lr->function); free(lr->file); free(lr->path); free(lr->comp_dir); intlist__delete(lr->line_list); memset(lr, 0, sizeof(*lr)); } int line_range__init(struct line_range *lr) { memset(lr, 0, sizeof(*lr)); lr->line_list = intlist__new(NULL); if (!lr->line_list) return -ENOMEM; else return 0; } static int parse_line_num(char **ptr, int *val, const char *what) { const char *start = *ptr; errno = 0; *val = strtol(*ptr, ptr, 0); if (errno || *ptr == start) { semantic_error("'%s' is not a valid number.\n", what); return -EINVAL; } return 0; } /* Check the name is good for event, group or function */ static bool is_c_func_name(const char *name) { if (!isalpha(*name) && *name != '_') return false; while (*++name != '\0') { if (!isalpha(*name) && !isdigit(*name) && *name != '_') return false; } return true; } /* * Stuff 'lr' according to the line range described by 'arg'. * The line range syntax is described by: * * SRC[:SLN[+NUM|-ELN]] * FNC[@SRC][:SLN[+NUM|-ELN]] */ int parse_line_range_desc(const char *arg, struct line_range *lr) { char *range, *file, *name = strdup(arg); int err; if (!name) return -ENOMEM; lr->start = 0; lr->end = INT_MAX; range = strchr(name, ':'); if (range) { *range++ = '\0'; err = parse_line_num(&range, &lr->start, "start line"); if (err) goto err; if (*range == '+' || *range == '-') { const char c = *range++; err = parse_line_num(&range, &lr->end, "end line"); if (err) goto err; if (c == '+') { lr->end += lr->start; /* * 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. */ lr->end--; } } pr_debug("Line range is %d to %d\n", lr->start, lr->end); err = -EINVAL; if (lr->start > lr->end) { semantic_error("Start line must be smaller" " than end line.\n"); goto err; } if (*range != '\0') { semantic_error("Tailing with invalid str '%s'.\n", range); goto err; } } file = strchr(name, '@'); if (file) { *file = '\0'; lr->file = strdup(++file); if (lr->file == NULL) { err = -ENOMEM; goto err; } lr->function = name; } else if (strchr(name, '/') || strchr(name, '.')) lr->file = name; else if (is_c_func_name(name))/* We reuse it for checking funcname */ lr->function = name; else { /* Invalid name */ semantic_error("'%s' is not a valid function name.\n", name); err = -EINVAL; goto err; } return 0; err: free(name); return err; } /* 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; bool file_spec = false; /* * * perf probe [EVENT=]SRC[:LN|;PTN] * perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT] * * TODO:Group name support */ if (!arg) return -EINVAL; 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 (!is_c_func_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; } /* * Check arg is function or file name and copy it. * * We consider arg to be a file spec if and only if it satisfies * all of the below criteria:: * - it does not include any of "+@%", * - it includes one of ":;", and * - it has a period '.' in the name. * * Otherwise, we consider arg to be a function specification. */ if (!strpbrk(arg, "+@%") && (ptr = strpbrk(arg, ";:")) != NULL) { /* This is a file spec if it includes a '.' before ; or : */ if (memchr(arg, '.', ptr - arg)) file_spec = true; } ptr = strpbrk(arg, ";:+@%"); if (ptr) { nc = *ptr; *ptr++ = '\0'; } tmp = strdup(arg); if (tmp == NULL) return -ENOMEM; if (file_spec) pp->file = tmp; else 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; char *argv0_str = NULL, *fmt, *fmt1_str, *fmt2_str, *fmt3_str; 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. */ argv0_str = strdup(argv[0]); if (argv0_str == NULL) { ret = -ENOMEM; goto out; } fmt1_str = strtok_r(argv0_str, ":", &fmt); fmt2_str = strtok_r(NULL, "/", &fmt); fmt3_str = strtok_r(NULL, " \t", &fmt); if (fmt1_str == NULL || strlen(fmt1_str) != 1 || fmt2_str == NULL || fmt3_str == NULL) { semantic_error("Failed to parse event name: %s\n", argv[0]); ret = -EINVAL; goto out; } pr = fmt1_str[0]; tev->group = strdup(fmt2_str); tev->event = strdup(fmt3_str); if (tev->group == NULL || tev->event == NULL) { ret = -ENOMEM; goto out; } pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr); tp->retprobe = (pr == 'r'); /* Scan module name(if there), function name and offset */ p = strchr(argv[1], ':'); if (p) { tp->module = strndup(argv[1], p - argv[1]); p++; } else p = argv[1]; fmt1_str = strtok_r(p, "+", &fmt); if (fmt1_str[0] == '0') /* only the address started with 0x */ tp->address = strtoul(fmt1_str, NULL, 0); else { /* Only the symbol-based probe has offset */ tp->symbol = strdup(fmt1_str); if (tp->symbol == NULL) { ret = -ENOMEM; goto out; } fmt2_str = strtok_r(NULL, "", &fmt); if (fmt2_str == NULL) tp->offset = 0; else tp->offset = strtoul(fmt2_str, NULL, 10); } 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: free(argv0_str); 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: %d\n", 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) { tmp = pp->file; len = strlen(tmp); if (len > 30) { tmp = strchr(pp->file + len - 30, '/'); tmp = tmp ? tmp + 1 : pp->file + len - 30; } ret = e_snprintf(file, 32, "@%s", tmp); 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: %d\n", ret); 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 ", tp->retprobe ? 'r' : 'p', tev->group, tev->event); if (len <= 0) goto error; /* Uprobes must have tp->address and tp->module */ if (tev->uprobes && (!tp->address || !tp->module)) goto error; /* Use the tp->address for uprobes */ if (tev->uprobes) ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s:0x%lx", tp->module, tp->address); else ret = e_snprintf(buf + len, MAX_CMDLEN - len, "%s%s%s+%lu", tp->module ?: "", tp->module ? ":" : "", tp->symbol, tp->offset); if (ret <= 0) goto error; len += ret; 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 find_perf_probe_point_from_map(struct probe_trace_point *tp, struct perf_probe_point *pp, bool is_kprobe) { struct symbol *sym = NULL; struct map *map; u64 addr; int ret = -ENOENT; if (!is_kprobe) { map = dso__new_map(tp->module); if (!map) goto out; addr = tp->address; sym = map__find_symbol(map, addr, NULL); } else { addr = kernel_get_symbol_address_by_name(tp->symbol, true); if (addr) { addr += tp->offset; sym = __find_kernel_function(addr, &map); } } if (!sym) goto out; pp->retprobe = tp->retprobe; pp->offset = addr - map->unmap_ip(map, sym->start); pp->function = strdup(sym->name); ret = pp->function ? 0 : -ENOMEM; out: if (map && !is_kprobe) { map__delete(map); } return ret; } static int convert_to_perf_probe_point(struct probe_trace_point *tp, struct perf_probe_point *pp, bool is_kprobe) { char buf[128]; int ret; ret = find_perf_probe_point_from_dwarf(tp, pp, is_kprobe); if (!ret) return 0; ret = find_perf_probe_point_from_map(tp, pp, is_kprobe); if (!ret) return 0; pr_debug("Failed to find probe point from both of dwarf and map.\n"); if (tp->symbol) { pp->function = strdup(tp->symbol); pp->offset = tp->offset; } else if (!tp->module && !is_kprobe) { ret = e_snprintf(buf, 128, "0x%" PRIx64, (u64)tp->address); if (ret < 0) return ret; pp->function = strdup(buf); pp->offset = 0; } if (pp->function == NULL) return -ENOMEM; pp->retprobe = tp->retprobe; return 0; } static int convert_to_perf_probe_event(struct probe_trace_event *tev, struct perf_probe_event *pev, bool is_kprobe) { 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 = convert_to_perf_probe_point(&tev->point, &pev->point, is_kprobe); 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_arg_field *field, *next; int i; free(pev->event); free(pev->group); free(pev->target); clear_perf_probe_point(&pev->point); for (i = 0; i < pev->nargs; i++) { free(pev->args[i].name); free(pev->args[i].var); free(pev->args[i].type); field = pev->args[i].field; while (field) { next = field->next; zfree(&field->name); free(field); field = next; } } 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; free(tev->event); free(tev->group); free(tev->point.symbol); free(tev->point.realname); free(tev->point.module); for (i = 0; i < tev->nargs; i++) { free(tev->args[i].name); free(tev->args[i].value); free(tev->args[i].type); ref = tev->args[i].ref; while (ref) { next = ref->next; free(ref); ref = next; } } free(tev->args); memset(tev, 0, sizeof(*tev)); } static void print_open_warning(int err, bool is_kprobe) { char sbuf[STRERR_BUFSIZE]; if (err == -ENOENT) { const char *config; if (!is_kprobe) config = "CONFIG_UPROBE_EVENTS"; else config = "CONFIG_KPROBE_EVENTS"; pr_warning("%cprobe_events file does not exist" " - please rebuild kernel with %s.\n", is_kprobe ? 'k' : 'u', config); } else if (err == -ENOTSUP) pr_warning("Tracefs or debugfs is not mounted.\n"); else pr_warning("Failed to open %cprobe_events: %s\n", is_kprobe ? 'k' : 'u', strerror_r(-err, sbuf, sizeof(sbuf))); } static void print_both_open_warning(int kerr, int uerr) { /* Both kprobes and uprobes are disabled, warn it. */ if (kerr == -ENOTSUP && uerr == -ENOTSUP) pr_warning("Tracefs or debugfs is not mounted.\n"); else if (kerr == -ENOENT && uerr == -ENOENT) pr_warning("Please rebuild kernel with CONFIG_KPROBE_EVENTS " "or/and CONFIG_UPROBE_EVENTS.\n"); else { char sbuf[STRERR_BUFSIZE]; pr_warning("Failed to open kprobe events: %s.\n", strerror_r(-kerr, sbuf, sizeof(sbuf))); pr_warning("Failed to open uprobe events: %s.\n", strerror_r(-uerr, sbuf, sizeof(sbuf))); } } static int open_probe_events(const char *trace_file, bool readwrite) { char buf[PATH_MAX]; const char *__debugfs; const char *tracing_dir = ""; int ret; __debugfs = tracefs_find_mountpoint(); if (__debugfs == NULL) { tracing_dir = "tracing/"; __debugfs = debugfs_find_mountpoint(); if (__debugfs == NULL) return -ENOTSUP; } ret = e_snprintf(buf, PATH_MAX, "%s/%s%s", __debugfs, tracing_dir, trace_file); 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, 0); else ret = open(buf, O_RDONLY, 0); if (ret < 0) ret = -errno; } return ret; } static int open_kprobe_events(bool readwrite) { return open_probe_events("kprobe_events", readwrite); } static int open_uprobe_events(bool readwrite) { return open_probe_events("uprobe_events", readwrite); } /* Get raw string list of current kprobe_events or uprobe_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 (%d)\n", ret); strlist__delete(sl); return NULL; } } fclose(fp); return sl; } struct kprobe_blacklist_node { struct list_head list; unsigned long start; unsigned long end; char *symbol; }; static void kprobe_blacklist__delete(struct list_head *blacklist) { struct kprobe_blacklist_node *node; while (!list_empty(blacklist)) { node = list_first_entry(blacklist, struct kprobe_blacklist_node, list); list_del(&node->list); free(node->symbol); free(node); } } static int kprobe_blacklist__load(struct list_head *blacklist) { struct kprobe_blacklist_node *node; const char *__debugfs = debugfs_find_mountpoint(); char buf[PATH_MAX], *p; FILE *fp; int ret; if (__debugfs == NULL) return -ENOTSUP; ret = e_snprintf(buf, PATH_MAX, "%s/kprobes/blacklist", __debugfs); if (ret < 0) return ret; fp = fopen(buf, "r"); if (!fp) return -errno; ret = 0; while (fgets(buf, PATH_MAX, fp)) { node = zalloc(sizeof(*node)); if (!node) { ret = -ENOMEM; break; } INIT_LIST_HEAD(&node->list); list_add_tail(&node->list, blacklist); if (sscanf(buf, "0x%lx-0x%lx", &node->start, &node->end) != 2) { ret = -EINVAL; break; } p = strchr(buf, '\t'); if (p) { p++; if (p[strlen(p) - 1] == '\n') p[strlen(p) - 1] = '\0'; } else p = (char *)"unknown"; node->symbol = strdup(p); if (!node->symbol) { ret = -ENOMEM; break; } pr_debug2("Blacklist: 0x%lx-0x%lx, %s\n", node->start, node->end, node->symbol); ret++; } if (ret < 0) kprobe_blacklist__delete(blacklist); fclose(fp); return ret; } static struct kprobe_blacklist_node * kprobe_blacklist__find_by_address(struct list_head *blacklist, unsigned long address) { struct kprobe_blacklist_node *node; list_for_each_entry(node, blacklist, list) { if (node->start <= address && address <= node->end) return node; } return NULL; } /* Show an event */ static int show_perf_probe_event(struct perf_probe_event *pev, const char *module) { 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; pr_info(" %-20s (on %s", buf, place); if (module) pr_info(" in %s", module); if (pev->nargs > 0) { pr_info(" with"); for (i = 0; i < pev->nargs; i++) { ret = synthesize_perf_probe_arg(&pev->args[i], buf, 128); if (ret < 0) break; pr_info(" %s", buf); } } pr_info(")\n"); free(place); return ret; } static bool filter_probe_trace_event(struct probe_trace_event *tev, struct strfilter *filter) { char tmp[128]; /* At first, check the event name itself */ if (strfilter__compare(filter, tev->event)) return true; /* Next, check the combination of name and group */ if (e_snprintf(tmp, 128, "%s:%s", tev->group, tev->event) < 0) return false; return strfilter__compare(filter, tmp); } static int __show_perf_probe_events(int fd, bool is_kprobe, struct strfilter *filter) { int ret = 0; struct probe_trace_event tev; struct perf_probe_event pev; struct strlist *rawlist; struct str_node *ent; memset(&tev, 0, sizeof(tev)); memset(&pev, 0, sizeof(pev)); rawlist = get_probe_trace_command_rawlist(fd); if (!rawlist) return -ENOMEM; strlist__for_each(ent, rawlist) { ret = parse_probe_trace_command(ent->s, &tev); if (ret >= 0) { if (!filter_probe_trace_event(&tev, filter)) goto next; ret = convert_to_perf_probe_event(&tev, &pev, is_kprobe); if (ret >= 0) ret = show_perf_probe_event(&pev, tev.point.module); } next: clear_perf_probe_event(&pev); clear_probe_trace_event(&tev); if (ret < 0) break; } strlist__delete(rawlist); return ret; } /* List up current perf-probe events */ int show_perf_probe_events(struct strfilter *filter) { int kp_fd, up_fd, ret; setup_pager(); ret = init_symbol_maps(false); if (ret < 0) return ret; kp_fd = open_kprobe_events(false); if (kp_fd >= 0) { ret = __show_perf_probe_events(kp_fd, true, filter); close(kp_fd); if (ret < 0) goto out; } up_fd = open_uprobe_events(false); if (kp_fd < 0 && up_fd < 0) { print_both_open_warning(kp_fd, up_fd); ret = kp_fd; goto out; } if (up_fd >= 0) { ret = __show_perf_probe_events(up_fd, false, filter); close(up_fd); } out: exit_symbol_maps(); 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); if (!rawlist) return NULL; 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); char sbuf[STRERR_BUFSIZE]; 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) { ret = -errno; pr_warning("Failed to write event: %s\n", strerror_r(errno, sbuf, sizeof(sbuf))); } } 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; if (*base == '.') base++; /* Try no suffix */ ret = e_snprintf(buf, len, "%s", base); if (ret < 0) { pr_debug("snprintf() failed: %d\n", 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: %d\n", 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; } /* Warn if the current kernel's uprobe implementation is old */ static void warn_uprobe_event_compat(struct probe_trace_event *tev) { int i; char *buf = synthesize_probe_trace_command(tev); /* Old uprobe event doesn't support memory dereference */ if (!tev->uprobes || tev->nargs == 0 || !buf) goto out; for (i = 0; i < tev->nargs; i++) if (strglobmatch(tev->args[i].value, "[$@+-]*")) { pr_warning("Please upgrade your kernel to at least " "3.14 to have access to feature %s\n", tev->args[i].value); break; } out: free(buf); } 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; LIST_HEAD(blacklist); struct kprobe_blacklist_node *node; bool safename; if (pev->uprobes) fd = open_uprobe_events(true); else fd = open_kprobe_events(true); if (fd < 0) { print_open_warning(fd, !pev->uprobes); 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"); ret = -ENOMEM; goto close_out; } /* Get kprobe blacklist if exists */ if (!pev->uprobes) { ret = kprobe_blacklist__load(&blacklist); if (ret < 0) pr_debug("No kprobe blacklist support, ignored\n"); } safename = (pev->point.function && !strisglob(pev->point.function)); ret = 0; pr_info("Added new event%s\n", (ntevs > 1) ? "s:" : ":"); for (i = 0; i < ntevs; i++) { tev = &tevs[i]; /* Skip if the symbol is out of .text (marked previously) */ if (!tev->point.symbol) continue; /* Ensure that the address is NOT blacklisted */ node = kprobe_blacklist__find_by_address(&blacklist, tev->point.address); if (node) { pr_warning("Warning: Skipped probing on blacklisted function: %s\n", node->symbol); continue; } if (pev->event) event = pev->event; else if (safename) event = pev->point.function; else event = tev->point.realname; 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, tev->point.module); /* 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 == -EINVAL && pev->uprobes) warn_uprobe_event_compat(tev); /* Note that it is possible to skip all events because of blacklist */ if (ret >= 0 && tev->event) { /* Show how to use the event. */ pr_info("\nYou can now use it in all perf tools, such as:\n\n"); pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", tev->group, tev->event); } kprobe_blacklist__delete(&blacklist); strlist__delete(namelist); close_out: close(fd); return ret; } static int find_probe_functions(struct map *map, char *name) { int found = 0; struct symbol *sym; struct rb_node *tmp; if (map__load(map, NULL) < 0) return 0; map__for_each_symbol(map, sym, tmp) { if (strglobmatch(sym->name, name)) found++; } return found; } #define strdup_or_goto(str, label) \ ({ char *__p = strdup(str); if (!__p) goto label; __p; }) void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused, struct probe_trace_event *tev __maybe_unused, struct map *map __maybe_unused) { } /* * Find probe function addresses from map. * Return an error or the number of found probe_trace_event */ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, struct probe_trace_event **tevs) { struct map *map = NULL; struct ref_reloc_sym *reloc_sym = NULL; struct symbol *sym; struct probe_trace_event *tev; struct perf_probe_point *pp = &pev->point; struct probe_trace_point *tp; int num_matched_functions; int ret, i; map = get_target_map(pev->target, pev->uprobes); if (!map) { ret = -EINVAL; goto out; } /* * Load matched symbols: Since the different local symbols may have * same name but different addresses, this lists all the symbols. */ num_matched_functions = find_probe_functions(map, pp->function); if (num_matched_functions == 0) { pr_err("Failed to find symbol %s in %s\n", pp->function, pev->target ? : "kernel"); ret = -ENOENT; goto out; } else if (num_matched_functions > probe_conf.max_probes) { pr_err("Too many functions matched in %s\n", pev->target ? : "kernel"); ret = -E2BIG; goto out; } if (!pev->uprobes && !pp->retprobe) { reloc_sym = kernel_get_ref_reloc_sym(); if (!reloc_sym) { pr_warning("Relocated base symbol is not found!\n"); ret = -EINVAL; goto out; } } /* Setup result trace-probe-events */ *tevs = zalloc(sizeof(*tev) * num_matched_functions); if (!*tevs) { ret = -ENOMEM; goto out; } ret = 0; map__for_each_symbol_by_name(map, pp->function, sym) { tev = (*tevs) + ret; tp = &tev->point; if (ret == num_matched_functions) { pr_warning("Too many symbols are listed. Skip it.\n"); break; } ret++; if (pp->offset > sym->end - sym->start) { pr_warning("Offset %ld is bigger than the size of %s\n", pp->offset, sym->name); ret = -ENOENT; goto err_out; } /* Add one probe point */ tp->address = map->unmap_ip(map, sym->start) + pp->offset; if (reloc_sym) { tp->symbol = strdup_or_goto(reloc_sym->name, nomem_out); tp->offset = tp->address - reloc_sym->addr; } else { tp->symbol = strdup_or_goto(sym->name, nomem_out); tp->offset = pp->offset; } tp->retprobe = pp->retprobe; if (pev->target) tev->point.module = strdup_or_goto(pev->target, nomem_out); tev->uprobes = pev->uprobes; tev->nargs = pev->nargs; if (tev->nargs) { tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs); if (tev->args == NULL) goto nomem_out; } for (i = 0; i < tev->nargs; i++) { if (pev->args[i].name) tev->args[i].name = strdup_or_goto(pev->args[i].name, nomem_out); tev->args[i].value = strdup_or_goto(pev->args[i].var, nomem_out); if (pev->args[i].type) tev->args[i].type = strdup_or_goto(pev->args[i].type, nomem_out); } arch__fix_tev_from_maps(pev, tev, map); } out: put_target_map(map, pev->uprobes); return ret; nomem_out: ret = -ENOMEM; err_out: clear_probe_trace_events(*tevs, num_matched_functions); zfree(tevs); goto out; } bool __weak arch__prefers_symtab(void) { return false; } static int convert_to_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event **tevs) { int ret; if (pev->uprobes && !pev->group) { /* Replace group name if not given */ ret = convert_exec_to_group(pev->target, &pev->group); if (ret != 0) { pr_warning("Failed to make a group name.\n"); return ret; } } if (arch__prefers_symtab() && !perf_probe_event_need_dwarf(pev)) { ret = find_probe_trace_events_from_map(pev, tevs); if (ret > 0) return ret; /* Found in symbol table */ } /* Convert perf_probe_event with debuginfo */ ret = try_to_find_probe_trace_events(pev, tevs); if (ret != 0) return ret; /* Found in debuginfo or got an error */ return find_probe_trace_events_from_map(pev, tevs); } 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 i, j, ret; struct __event_package *pkgs; ret = 0; pkgs = zalloc(sizeof(struct __event_package) * npevs); if (pkgs == NULL) return -ENOMEM; ret = init_symbol_maps(pevs->uprobes); 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); if (ret < 0) goto end; pkgs[i].ntevs = ret; } /* Loop 2: add all events */ for (i = 0; i < npevs; i++) { ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs, pkgs[i].ntevs, probe_conf.force_add); if (ret < 0) break; } 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]); zfree(&pkgs[i].tevs); } free(pkgs); exit_symbol_maps(); 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) { ret = -errno; goto error; } pr_info("Removed event: %s\n", ent->s); return 0; error: pr_warning("Failed to delete event: %s\n", strerror_r(-ret, buf, sizeof(buf))); return ret; } static int del_trace_probe_events(int fd, struct strfilter *filter, struct strlist *namelist) { struct str_node *ent; const char *p; int ret = -ENOENT; if (!namelist) return -ENOENT; strlist__for_each(ent, namelist) { p = strchr(ent->s, ':'); if ((p && strfilter__compare(filter, p + 1)) || strfilter__compare(filter, ent->s)) { ret = __del_trace_probe_event(fd, ent); if (ret < 0) break; } } return ret; } int del_perf_probe_events(struct strfilter *filter) { int ret, ret2, ufd = -1, kfd = -1; struct strlist *namelist = NULL, *unamelist = NULL; char *str = strfilter__string(filter); if (!str) return -EINVAL; pr_debug("Delete filter: \'%s\'\n", str); /* Get current event names */ kfd = open_kprobe_events(true); if (kfd >= 0) namelist = get_probe_trace_event_names(kfd, true); ufd = open_uprobe_events(true); if (ufd >= 0) unamelist = get_probe_trace_event_names(ufd, true); if (kfd < 0 && ufd < 0) { print_both_open_warning(kfd, ufd); ret = kfd; goto error; } ret = del_trace_probe_events(kfd, filter, namelist); if (ret < 0 && ret != -ENOENT) goto error; ret2 = del_trace_probe_events(ufd, filter, unamelist); if (ret2 < 0 && ret2 != -ENOENT) ret = ret2; else if (ret == -ENOENT && ret2 == -ENOENT) { pr_debug("\"%s\" does not hit any event.\n", str); /* Note that this is silently ignored */ ret = 0; } error: if (kfd >= 0) { strlist__delete(namelist); close(kfd); } if (ufd >= 0) { strlist__delete(unamelist); close(ufd); } free(str); return ret; } /* TODO: don't use a global variable for filter ... */ static struct strfilter *available_func_filter; /* * If a symbol corresponds to a function with global binding and * matches filter return 0. For all others return 1. */ static int filter_available_functions(struct map *map __maybe_unused, struct symbol *sym) { if (strfilter__compare(available_func_filter, sym->name)) return 0; return 1; } int show_available_funcs(const char *target, struct strfilter *_filter, bool user) { struct map *map; int ret; ret = init_symbol_maps(user); if (ret < 0) return ret; /* Get a symbol map */ if (user) map = dso__new_map(target); else map = kernel_get_module_map(target); if (!map) { pr_err("Failed to get a map for %s\n", (target) ? : "kernel"); return -EINVAL; } /* Load symbols with given filter */ available_func_filter = _filter; if (map__load(map, filter_available_functions)) { pr_err("Failed to load symbols in %s\n", (target) ? : "kernel"); goto end; } if (!dso__sorted_by_name(map->dso, map->type)) dso__sort_by_name(map->dso, map->type); /* Show all (filtered) symbols */ setup_pager(); dso__fprintf_symbols_by_name(map->dso, map->type, stdout); end: if (user) { map__delete(map); } exit_symbol_maps(); return ret; }