| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * probe-event.c : perf-probe definition to probe_events format converter |
| * |
| * Written by Masami Hiramatsu <mhiramat@redhat.com> |
| */ |
| |
| #include <inttypes.h> |
| #include <sys/utsname.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| #include <errno.h> |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <stdarg.h> |
| #include <limits.h> |
| #include <elf.h> |
| |
| #include "build-id.h" |
| #include "event.h" |
| #include "namespaces.h" |
| #include "strlist.h" |
| #include "strfilter.h" |
| #include "debug.h" |
| #include "dso.h" |
| #include "color.h" |
| #include "map.h" |
| #include "map_groups.h" |
| #include "symbol.h" |
| #include <api/fs/fs.h> |
| #include "trace-event.h" /* For __maybe_unused */ |
| #include "probe-event.h" |
| #include "probe-finder.h" |
| #include "probe-file.h" |
| #include "session.h" |
| #include "string2.h" |
| #include "strbuf.h" |
| |
| #include <subcmd/pager.h> |
| #include <linux/ctype.h> |
| #include <linux/zalloc.h> |
| |
| #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) |
| |
| 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 struct machine *host_machine; |
| |
| /* Initialize symbol maps and path of vmlinux/modules */ |
| int init_probe_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; |
| } |
| |
| void exit_probe_symbol_maps(void) |
| { |
| machine__delete(host_machine); |
| host_machine = NULL; |
| symbol__exit(); |
| } |
| |
| static struct ref_reloc_sym *kernel_get_ref_reloc_sym(struct map **pmap) |
| { |
| /* kmap->ref_reloc_sym should be set if host_machine is initialized */ |
| struct kmap *kmap; |
| struct map *map = machine__kernel_map(host_machine); |
| |
| if (map__load(map) < 0) |
| return NULL; |
| |
| kmap = map__kmap(map); |
| if (!kmap) |
| return NULL; |
| |
| if (pmap) |
| *pmap = map; |
| |
| return kmap->ref_reloc_sym; |
| } |
| |
| static int kernel_get_symbol_address_by_name(const char *name, u64 *addr, |
| bool reloc, bool reladdr) |
| { |
| 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(NULL); |
| if (reloc_sym && strcmp(name, reloc_sym->name) == 0) |
| *addr = (reloc) ? reloc_sym->addr : reloc_sym->unrelocated_addr; |
| else { |
| sym = machine__find_kernel_symbol_by_name(host_machine, name, &map); |
| if (!sym) |
| return -ENOENT; |
| *addr = map->unmap_ip(map, sym->start) - |
| ((reloc) ? 0 : map->reloc) - |
| ((reladdr) ? map->start : 0); |
| } |
| return 0; |
| } |
| |
| static struct map *kernel_get_module_map(const char *module) |
| { |
| struct maps *maps = machine__kernel_maps(host_machine); |
| struct map *pos; |
| |
| /* A file path -- this is an offline module */ |
| if (module && strchr(module, '/')) |
| return dso__new_map(module); |
| |
| if (!module) { |
| pos = machine__kernel_map(host_machine); |
| return map__get(pos); |
| } |
| |
| for (pos = maps__first(maps); pos; pos = map__next(pos)) { |
| /* short_name is "[module]" */ |
| if (strncmp(pos->dso->short_name + 1, module, |
| pos->dso->short_name_len - 2) == 0 && |
| module[pos->dso->short_name_len - 2] == '\0') { |
| return map__get(pos); |
| } |
| } |
| return NULL; |
| } |
| |
| struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user) |
| { |
| /* Init maps of given executable or kernel */ |
| if (user) { |
| struct map *map; |
| |
| map = dso__new_map(target); |
| if (map && map->dso) |
| map->dso->nsinfo = nsinfo__get(nsi); |
| return map; |
| } else { |
| return kernel_get_module_map(target); |
| } |
| } |
| |
| 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; |
| } |
| |
| for (ptr2 = ptr1; *ptr2 != '\0'; ptr2++) { |
| if (!isalnum(*ptr2) && *ptr2 != '_') { |
| *ptr2 = '\0'; |
| break; |
| } |
| } |
| |
| 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) |
| { |
| zfree(&pp->file); |
| zfree(&pp->function); |
| zfree(&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); |
| } |
| |
| static bool kprobe_blacklist__listed(unsigned long address); |
| static bool kprobe_warn_out_range(const char *symbol, unsigned long address) |
| { |
| struct map *map; |
| bool ret = false; |
| |
| map = kernel_get_module_map(NULL); |
| if (map) { |
| ret = address <= map->start || map->end < address; |
| if (ret) |
| pr_warning("%s is out of .text, skip it.\n", symbol); |
| map__put(map); |
| } |
| if (!ret && kprobe_blacklist__listed(address)) { |
| pr_warning("%s is blacklisted function, skip it.\n", symbol); |
| ret = true; |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * @module can be module name of module file path. In case of path, |
| * inspect elf and find out what is actual module name. |
| * Caller has to free mod_name after using it. |
| */ |
| static char *find_module_name(const char *module) |
| { |
| int fd; |
| Elf *elf; |
| GElf_Ehdr ehdr; |
| GElf_Shdr shdr; |
| Elf_Data *data; |
| Elf_Scn *sec; |
| char *mod_name = NULL; |
| int name_offset; |
| |
| fd = open(module, O_RDONLY); |
| if (fd < 0) |
| return NULL; |
| |
| elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); |
| if (elf == NULL) |
| goto elf_err; |
| |
| if (gelf_getehdr(elf, &ehdr) == NULL) |
| goto ret_err; |
| |
| sec = elf_section_by_name(elf, &ehdr, &shdr, |
| ".gnu.linkonce.this_module", NULL); |
| if (!sec) |
| goto ret_err; |
| |
| data = elf_getdata(sec, NULL); |
| if (!data || !data->d_buf) |
| goto ret_err; |
| |
| /* |
| * NOTE: |
| * '.gnu.linkonce.this_module' section of kernel module elf directly |
| * maps to 'struct module' from linux/module.h. This section contains |
| * actual module name which will be used by kernel after loading it. |
| * But, we cannot use 'struct module' here since linux/module.h is not |
| * exposed to user-space. Offset of 'name' has remained same from long |
| * time, so hardcoding it here. |
| */ |
| if (ehdr.e_ident[EI_CLASS] == ELFCLASS32) |
| name_offset = 12; |
| else /* expect ELFCLASS64 by default */ |
| name_offset = 24; |
| |
| mod_name = strdup((char *)data->d_buf + name_offset); |
| |
| ret_err: |
| elf_end(elf); |
| elf_err: |
| close(fd); |
| return mod_name; |
| } |
| |
| #ifdef HAVE_DWARF_SUPPORT |
| |
| 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) { |
| char module_name[128]; |
| |
| snprintf(module_name, sizeof(module_name), "[%s]", module); |
| map = map_groups__find_by_name(&host_machine->kmaps, module_name); |
| if (map) { |
| dso = map->dso; |
| goto found; |
| } |
| pr_debug("Failed to find module %s.\n", module); |
| return -ENOENT; |
| } |
| |
| map = machine__kernel_map(host_machine); |
| 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); |
| else |
| ret = dso__load_vmlinux_path(dso, map); |
| found: |
| *pdso = dso; |
| return ret; |
| } |
| |
| /* |
| * 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, struct nsinfo *nsi, |
| 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, nsi, 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) - map->reloc; |
| 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: |
| map__put(map); |
| 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->nsi, 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, NULL, 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, struct nsinfo *nsi, |
| bool silent) |
| { |
| const char *path = module; |
| char reason[STRERR_BUFSIZE]; |
| struct debuginfo *ret = NULL; |
| struct dso *dso = NULL; |
| struct nscookie nsc; |
| int err; |
| |
| if (!module || !strchr(module, '/')) { |
| err = kernel_get_module_dso(module, &dso); |
| if (err < 0) { |
| if (!dso || dso->load_errno == 0) { |
| if (!str_error_r(-err, reason, STRERR_BUFSIZE)) |
| strcpy(reason, "(unknown)"); |
| } else |
| dso__strerror_load(dso, reason, STRERR_BUFSIZE); |
| if (!silent) { |
| if (module) |
| pr_err("Module %s is not loaded, please specify its full path name.\n", module); |
| else |
| pr_err("Failed to find the path for the kernel: %s\n", reason); |
| } |
| return NULL; |
| } |
| path = dso->long_name; |
| } |
| nsinfo__mountns_enter(nsi, &nsc); |
| 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"); |
| } |
| nsinfo__mountns_exit(&nsc); |
| return ret; |
| } |
| |
| /* For caching the last debuginfo */ |
| static struct debuginfo *debuginfo_cache; |
| static char *debuginfo_cache_path; |
| |
| static struct debuginfo *debuginfo_cache__open(const char *module, bool silent) |
| { |
| const char *path = module; |
| |
| /* If the module is NULL, it should be the kernel. */ |
| if (!module) |
| path = "kernel"; |
| |
| if (debuginfo_cache_path && !strcmp(debuginfo_cache_path, path)) |
| goto out; |
| |
| /* Copy module path */ |
| free(debuginfo_cache_path); |
| debuginfo_cache_path = strdup(path); |
| if (!debuginfo_cache_path) { |
| debuginfo__delete(debuginfo_cache); |
| debuginfo_cache = NULL; |
| goto out; |
| } |
| |
| debuginfo_cache = open_debuginfo(module, NULL, silent); |
| if (!debuginfo_cache) |
| zfree(&debuginfo_cache_path); |
| out: |
| return debuginfo_cache; |
| } |
| |
| static void debuginfo_cache__exit(void) |
| { |
| debuginfo__delete(debuginfo_cache); |
| debuginfo_cache = NULL; |
| zfree(&debuginfo_cache_path); |
| } |
| |
| |
| static int get_text_start_address(const char *exec, unsigned long *address, |
| struct nsinfo *nsi) |
| { |
| Elf *elf; |
| GElf_Ehdr ehdr; |
| GElf_Shdr shdr; |
| int fd, ret = -ENOENT; |
| struct nscookie nsc; |
| |
| nsinfo__mountns_enter(nsi, &nsc); |
| fd = open(exec, O_RDONLY); |
| nsinfo__mountns_exit(&nsc); |
| if (fd < 0) |
| return -errno; |
| |
| elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); |
| if (elf == NULL) { |
| ret = -EINVAL; |
| goto out_close; |
| } |
| |
| 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); |
| out_close: |
| close(fd); |
| |
| 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, NULL); |
| if (ret < 0) |
| goto error; |
| addr += stext; |
| } else if (tp->symbol) { |
| /* If the module is given, this returns relative address */ |
| ret = kernel_get_symbol_address_by_name(tp->symbol, &addr, |
| false, !!tp->module); |
| if (ret != 0) |
| goto error; |
| addr += tp->offset; |
| } |
| |
| pr_debug("try to find information at %" PRIx64 " in %s\n", addr, |
| tp->module ? : "kernel"); |
| |
| dinfo = debuginfo_cache__open(tp->module, verbose <= 0); |
| if (dinfo) |
| ret = debuginfo__find_probe_point(dinfo, |
| (unsigned long)addr, pp); |
| 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; |
| } |
| |
| /* Adjust symbol name and address */ |
| static int post_process_probe_trace_point(struct probe_trace_point *tp, |
| struct map *map, unsigned long offs) |
| { |
| struct symbol *sym; |
| u64 addr = tp->address - offs; |
| |
| sym = map__find_symbol(map, addr); |
| if (!sym) |
| return -ENOENT; |
| |
| if (strcmp(sym->name, tp->symbol)) { |
| /* If we have no realname, use symbol for it */ |
| if (!tp->realname) |
| tp->realname = tp->symbol; |
| else |
| free(tp->symbol); |
| tp->symbol = strdup(sym->name); |
| if (!tp->symbol) |
| return -ENOMEM; |
| } |
| tp->offset = addr - sym->start; |
| tp->address -= offs; |
| |
| return 0; |
| } |
| |
| /* |
| * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions |
| * and generate new symbols with suffixes such as .constprop.N or .isra.N |
| * etc. Since those symbols are not recorded in DWARF, we have to find |
| * correct generated symbols from offline ELF binary. |
| * For online kernel or uprobes we don't need this because those are |
| * rebased on _text, or already a section relative address. |
| */ |
| static int |
| post_process_offline_probe_trace_events(struct probe_trace_event *tevs, |
| int ntevs, const char *pathname) |
| { |
| struct map *map; |
| unsigned long stext = 0; |
| int i, ret = 0; |
| |
| /* Prepare a map for offline binary */ |
| map = dso__new_map(pathname); |
| if (!map || get_text_start_address(pathname, &stext, NULL) < 0) { |
| pr_warning("Failed to get ELF symbols for %s\n", pathname); |
| return -EINVAL; |
| } |
| |
| for (i = 0; i < ntevs; i++) { |
| ret = post_process_probe_trace_point(&tevs[i].point, |
| map, stext); |
| if (ret < 0) |
| break; |
| } |
| map__put(map); |
| |
| return ret; |
| } |
| |
| static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs, |
| int ntevs, const char *exec, |
| struct nsinfo *nsi) |
| { |
| int i, ret = 0; |
| unsigned long stext = 0; |
| |
| if (!exec) |
| return 0; |
| |
| ret = get_text_start_address(exec, &stext, nsi); |
| if (ret < 0) |
| return ret; |
| |
| for (i = 0; i < ntevs && ret >= 0; i++) { |
| /* point.address is the address 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 |
| post_process_module_probe_trace_events(struct probe_trace_event *tevs, |
| int ntevs, const char *module, |
| struct debuginfo *dinfo) |
| { |
| Dwarf_Addr text_offs = 0; |
| int i, ret = 0; |
| char *mod_name = NULL; |
| struct map *map; |
| |
| if (!module) |
| return 0; |
| |
| map = get_target_map(module, NULL, false); |
| if (!map || debuginfo__get_text_offset(dinfo, &text_offs, true) < 0) { |
| pr_warning("Failed to get ELF symbols for %s\n", module); |
| return -EINVAL; |
| } |
| |
| mod_name = find_module_name(module); |
| for (i = 0; i < ntevs; i++) { |
| ret = post_process_probe_trace_point(&tevs[i].point, |
| map, (unsigned long)text_offs); |
| if (ret < 0) |
| break; |
| tevs[i].point.module = |
| strdup(mod_name ? mod_name : module); |
| if (!tevs[i].point.module) { |
| ret = -ENOMEM; |
| break; |
| } |
| } |
| |
| free(mod_name); |
| map__put(map); |
| |
| return ret; |
| } |
| |
| static int |
| post_process_kernel_probe_trace_events(struct probe_trace_event *tevs, |
| int ntevs) |
| { |
| struct ref_reloc_sym *reloc_sym; |
| struct map *map; |
| char *tmp; |
| int i, skipped = 0; |
| |
| /* Skip post process if the target is an offline kernel */ |
| if (symbol_conf.ignore_vmlinux_buildid) |
| return post_process_offline_probe_trace_events(tevs, ntevs, |
| symbol_conf.vmlinux_name); |
| |
| reloc_sym = kernel_get_ref_reloc_sym(&map); |
| if (!reloc_sym) { |
| pr_warning("Relocated base symbol is not found!\n"); |
| return -EINVAL; |
| } |
| |
| for (i = 0; i < ntevs; i++) { |
| if (!tevs[i].point.address) |
| continue; |
| if (tevs[i].point.retprobe && !kretprobe_offset_is_supported()) |
| continue; |
| /* |
| * If we found a wrong one, mark it by NULL symbol. |
| * Since addresses in debuginfo is same as objdump, we need |
| * to convert it to addresses on memory. |
| */ |
| if (kprobe_warn_out_range(tevs[i].point.symbol, |
| map__objdump_2mem(map, tevs[i].point.address))) { |
| 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; |
| } |
| |
| void __weak |
| arch__post_process_probe_trace_events(struct perf_probe_event *pev __maybe_unused, |
| int ntevs __maybe_unused) |
| { |
| } |
| |
| /* Post processing the probe events */ |
| static int post_process_probe_trace_events(struct perf_probe_event *pev, |
| struct probe_trace_event *tevs, |
| int ntevs, const char *module, |
| bool uprobe, struct debuginfo *dinfo) |
| { |
| int ret; |
| |
| if (uprobe) |
| ret = add_exec_to_probe_trace_events(tevs, ntevs, module, |
| pev->nsi); |
| else if (module) |
| /* Currently ref_reloc_sym based probe is not for drivers */ |
| ret = post_process_module_probe_trace_events(tevs, ntevs, |
| module, dinfo); |
| else |
| ret = post_process_kernel_probe_trace_events(tevs, ntevs); |
| |
| if (ret >= 0) |
| arch__post_process_probe_trace_events(pev, ntevs); |
| |
| return ret; |
| } |
| |
| /* 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, pev->nsi, !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)); |
| } |
| } |
| |
| if (ntevs > 0) { /* Succeeded to find trace events */ |
| pr_debug("Found %d probe_trace_events.\n", ntevs); |
| ret = post_process_probe_trace_events(pev, *tevs, ntevs, |
| pev->target, pev->uprobes, dinfo); |
| if (ret < 0 || ret == ntevs) { |
| pr_debug("Post processing failed or all events are skipped. (%d)\n", ret); |
| clear_probe_trace_events(*tevs, ntevs); |
| zfree(tevs); |
| ntevs = 0; |
| } |
| } |
| |
| debuginfo__delete(dinfo); |
| |
| 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; |
| } else if (ntevs < 0) { |
| /* 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", |
| str_error_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, NULL, 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, |
| str_error_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_entry(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, |
| struct nsinfo *nsi, bool user) |
| { |
| int ret; |
| struct nscookie nsc; |
| |
| ret = init_probe_symbol_maps(user); |
| if (ret < 0) |
| return ret; |
| nsinfo__mountns_enter(nsi, &nsc); |
| ret = __show_line_range(lr, module, user); |
| nsinfo__mountns_exit(&nsc); |
| exit_probe_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_entry(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_probe_symbol_maps(pevs->uprobes); |
| if (ret < 0) |
| return ret; |
| |
| dinfo = open_debuginfo(pevs->target, pevs->nsi, 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_probe_symbol_maps(); |
| return ret; |
| } |
| |
| #else /* !HAVE_DWARF_SUPPORT */ |
| |
| static void debuginfo_cache__exit(void) |
| { |
| } |
| |
| 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, |
| struct nsinfo *nsi __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) |
| { |
| zfree(&lr->function); |
| zfree(&lr->file); |
| zfree(&lr->path); |
| zfree(&lr->comp_dir); |
| intlist__delete(lr->line_list); |
| } |
| |
| 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; |
| } |
| |
| static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev) |
| { |
| char *ptr; |
| |
| ptr = strpbrk_esc(*arg, ":"); |
| if (ptr) { |
| *ptr = '\0'; |
| if (!pev->sdt && !is_c_func_name(*arg)) |
| goto ng_name; |
| pev->group = strdup_esc(*arg); |
| if (!pev->group) |
| return -ENOMEM; |
| *arg = ptr + 1; |
| } else |
| pev->group = NULL; |
| |
| pev->event = strdup_esc(*arg); |
| if (pev->event == NULL) |
| return -ENOMEM; |
| |
| if (!pev->sdt && !is_c_func_name(pev->event)) { |
| zfree(&pev->event); |
| ng_name: |
| zfree(&pev->group); |
| semantic_error("%s is bad for event name -it must " |
| "follow C symbol-naming rule.\n", *arg); |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| /* 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; |
| int ret; |
| |
| /* |
| * <Syntax> |
| * perf probe [GRP:][EVENT=]SRC[:LN|;PTN] |
| * perf probe [GRP:][EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT] |
| * perf probe %[GRP:]SDT_EVENT |
| */ |
| if (!arg) |
| return -EINVAL; |
| |
| if (is_sdt_event(arg)) { |
| pev->sdt = true; |
| if (arg[0] == '%') |
| arg++; |
| } |
| |
| ptr = strpbrk_esc(arg, ";=@+%"); |
| if (pev->sdt) { |
| if (ptr) { |
| if (*ptr != '@') { |
| semantic_error("%s must be an SDT name.\n", |
| arg); |
| return -EINVAL; |
| } |
| /* This must be a target file name or build id */ |
| tmp = build_id_cache__complement(ptr + 1); |
| if (tmp) { |
| pev->target = build_id_cache__origname(tmp); |
| free(tmp); |
| } else |
| pev->target = strdup_esc(ptr + 1); |
| if (!pev->target) |
| return -ENOMEM; |
| *ptr = '\0'; |
| } |
| ret = parse_perf_probe_event_name(&arg, pev); |
| if (ret == 0) { |
| if (asprintf(&pev->point.function, "%%%s", pev->event) < 0) |
| ret = -errno; |
| } |
| return ret; |
| } |
| |
| if (ptr && *ptr == '=') { /* Event name */ |
| *ptr = '\0'; |
| tmp = ptr + 1; |
| ret = parse_perf_probe_event_name(&arg, pev); |
| if (ret < 0) |
| return ret; |
| |
| 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_esc(arg, "+@%")) { |
| ptr = strpbrk_esc(arg, ";:"); |
| /* This is a file spec if it includes a '.' before ; or : */ |
| if (ptr && memchr(arg, '.', ptr - arg)) |
| file_spec = true; |
| } |
| |
| ptr = strpbrk_esc(arg, ";:+@%"); |
| if (ptr) { |
| nc = *ptr; |
| *ptr++ = '\0'; |
| } |
| |
| if (arg[0] == '\0') |
| tmp = NULL; |
| else { |
| tmp = strdup_esc(arg); |
| if (tmp == NULL) |
| return -ENOMEM; |
| } |
| |
| if (file_spec) |
| pp->file = tmp; |
| else { |
| pp->function = tmp; |
| |
| /* |
| * Keep pp->function even if this is absolute address, |
| * so it can mark whether abs_address is valid. |
| * Which make 'perf probe lib.bin 0x0' possible. |
| * |
| * Note that checking length of tmp is not needed |
| * because when we access tmp[1] we know tmp[0] is '0', |
| * so tmp[1] should always valid (but could be '\0'). |
| */ |
| if (tmp && !strncmp(tmp, "0x", 2)) { |
| pp->abs_address = strtoul(pp->function, &tmp, 0); |
| if (*tmp != '\0') { |
| semantic_error("Invalid absolute address.\n"); |
| return -EINVAL; |
| } |
| } |
| } |
| |
| /* Parse other options */ |
| while (ptr) { |
| arg = ptr; |
| c = nc; |
| if (c == ';') { /* Lazy pattern must be the last part */ |
| pp->lazy_line = strdup(arg); /* let leave escapes */ |
| if (pp->lazy_line == NULL) |
| return -ENOMEM; |
| break; |
| } |
| ptr = strpbrk_esc(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_esc(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->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 && tmp != str && strcmp(tmp + 1, "user")) { /* user attr */ |
| if (!user_access_is_supported()) { |
| semantic_error("ftrace does not support user access\n"); |
| return -EINVAL; |
| } |
| *tmp = '\0'; |
| arg->user_access = true; |
| pr_debug("user_access "); |
| } |
| |
| 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; |
| } |
| |
| /* Returns true if *any* ARG is either C variable, $params or $vars. */ |
| bool perf_probe_with_var(struct perf_probe_event *pev) |
| { |
| int i = 0; |
| |
| for (i = 0; i < pev->nargs; i++) |
| if (is_c_varname(pev->args[i].var) || |
| !strcmp(pev->args[i].var, PROBE_ARG_PARAMS) || |
| !strcmp(pev->args[i].var, PROBE_ARG_VARS)) |
| return true; |
| return false; |
| } |
| |
| /* Return true if this perf_probe_event requires debuginfo */ |
| bool perf_probe_event_need_dwarf(struct perf_probe_event *pev) |
| { |
| if (pev->point.file || pev->point.line || pev->point.lazy_line) |
| return true; |
| |
| if (perf_probe_with_var(pev)) |
| return true; |
| |
| return false; |
| } |
| |
| /* Parse probe_events event into struct probe_point */ |
| 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 || 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]); |
| if (!tp->module) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| tev->uprobes = (tp->module[0] == '/'); |
| p++; |
| } else |
| p = argv[1]; |
| fmt1_str = strtok_r(p, "+", &fmt); |
| /* only the address started with 0x */ |
| if (fmt1_str[0] == '0') { |
| /* |
| * Fix a special case: |
| * if address == 0, kernel reports something like: |
| * p:probe_libc/abs_0 /lib/libc-2.18.so:0x (null) arg1=%ax |
| * Newer kernel may fix that, but we want to |
| * support old kernel also. |
| */ |
| if (strcmp(fmt1_str, "0x") == 0) { |
| if (!argv[2] || strcmp(argv[2], "(null)")) { |
| ret = -EINVAL; |
| goto out; |
| } |
| tp->address = 0; |
| |
| free(argv[2]); |
| for (i = 2; argv[i + 1] != NULL; i++) |
| argv[i] = argv[i + 1]; |
| |
| argv[i] = NULL; |
| argc -= 1; |
| } else |
| 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); |
| } |
| |
| if (tev->uprobes) { |
| fmt2_str = strchr(p, '('); |
| if (fmt2_str) |
| tp->ref_ctr_offset = strtoul(fmt2_str + 1, NULL, 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: |
| free(argv0_str); |
| argv_free(argv); |
| return ret; |
| } |
| |
| /* Compose only probe arg */ |
| char *synthesize_perf_probe_arg(struct perf_probe_arg *pa) |
| { |
| struct perf_probe_arg_field *field = pa->field; |
| struct strbuf buf; |
| char *ret = NULL; |
| int err; |
| |
| if (strbuf_init(&buf, 64) < 0) |
| return NULL; |
| |
| if (pa->name && pa->var) |
| err = strbuf_addf(&buf, "%s=%s", pa->name, pa->var); |
| else |
| err = strbuf_addstr(&buf, pa->name ?: pa->var); |
| if (err) |
| goto out; |
| |
| while (field) { |
| if (field->name[0] == '[') |
| err = strbuf_addstr(&buf, field->name); |
| else |
| err = strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".", |
| field->name); |
| field = field->next; |
| if (err) |
| goto out; |
| } |
| |
| if (pa->type) |
| if (strbuf_addf(&buf, ":%s", pa->type) < 0) |
| goto out; |
| |
| ret = strbuf_detach(&buf, NULL); |
| out: |
| strbuf_release(&buf); |
| return ret; |
| } |
| |
| /* Compose only probe point (not argument) */ |
| char *synthesize_perf_probe_point(struct perf_probe_point *pp) |
| { |
| struct strbuf buf; |
| char *tmp, *ret = NULL; |
| int len, err = 0; |
| |
| if (strbuf_init(&buf, 64) < 0) |
| return NULL; |
| |
| if (pp->function) { |
| if (strbuf_addstr(&buf, pp->function) < 0) |
| goto out; |
| if (pp->offset) |
| err = strbuf_addf(&buf, "+%lu", pp->offset); |
| else if (pp->line) |
| err = strbuf_addf(&buf, ":%d", pp->line); |
| else if (pp->retprobe) |
| err = strbuf_addstr(&buf, "%return"); |
| if (err) |
| goto out; |
| } |
| 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; |
| } |
| err = strbuf_addf(&buf, "@%s", tmp); |
| if (!err && !pp->function && pp->line) |
| err = strbuf_addf(&buf, ":%d", pp->line); |
| } |
| if (!err) |
| ret = strbuf_detach(&buf, NULL); |
| out: |
| strbuf_release(&buf); |
| return ret; |
| } |
| |
| char *synthesize_perf_probe_command(struct perf_probe_event *pev) |
| { |
| struct strbuf buf; |
| char *tmp, *ret = NULL; |
| int i; |
| |
| if (strbuf_init(&buf, 64)) |
| return NULL; |
| if (pev->event) |
| if (strbuf_addf(&buf, "%s:%s=", pev->group ?: PERFPROBE_GROUP, |
| pev->event) < 0) |
| goto out; |
| |
| tmp = synthesize_perf_probe_point(&pev->point); |
| if (!tmp || strbuf_addstr(&buf, tmp) < 0) |
| goto out; |
| free(tmp); |
| |
| for (i = 0; i < pev->nargs; i++) { |
| tmp = synthesize_perf_probe_arg(pev->args + i); |
| if (!tmp || strbuf_addf(&buf, " %s", tmp) < 0) |
| goto out; |
| free(tmp); |
| } |
| |
| ret = strbuf_detach(&buf, NULL); |
| out: |
| strbuf_release(&buf); |
| return ret; |
| } |
| |
| static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref, |
| struct strbuf *buf, int depth) |
| { |
| int err; |
| if (ref->next) { |
| depth = __synthesize_probe_trace_arg_ref(ref->next, buf, |
| depth + 1); |
| if (depth < 0) |
| return depth; |
| } |
| err = strbuf_addf(buf, "%+ld(", ref->offset); |
| return (err < 0) ? err : depth; |
| } |
| |
| static int synthesize_probe_trace_arg(struct probe_trace_arg *arg, |
| struct strbuf *buf) |
| { |
| struct probe_trace_arg_ref *ref = arg->ref; |
| int depth = 0, err; |
| |
| /* Argument name or separator */ |
| if (arg->name) |
| err = strbuf_addf(buf, " %s=", arg->name); |
| else |
| err = strbuf_addch(buf, ' '); |
| if (err) |
| return err; |
| |
| /* Special case: @XXX */ |
| if (arg->value[0] == '@' && arg->ref) |
| ref = ref->next; |
| |
| /* Dereferencing arguments */ |
| if (ref) { |
| depth = __synthesize_probe_trace_arg_ref(ref, buf, 1); |
| if (depth < 0) |
| return depth; |
| } |
| |
| /* Print argument value */ |
| if (arg->value[0] == '@' && arg->ref) |
| err = strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset); |
| else |
| err = strbuf_addstr(buf, arg->value); |
| |
| /* Closing */ |
| while (!err && depth--) |
| err = strbuf_addch(buf, ')'); |
| |
| /* Print argument type */ |
| if (!err && arg->type) |
| err = strbuf_addf(buf, ":%s", arg->type); |
| |
| return err; |
| } |
| |
| static int |
| synthesize_uprobe_trace_def(struct probe_trace_event *tev, struct strbuf *buf) |
| { |
| struct probe_trace_point *tp = &tev->point; |
| int err; |
| |
| err = strbuf_addf(buf, "%s:0x%lx", tp->module, tp->address); |
| |
| if (err >= 0 && tp->ref_ctr_offset) { |
| if (!uprobe_ref_ctr_is_supported()) |
| return -1; |
| err = strbuf_addf(buf, "(0x%lx)", tp->ref_ctr_offset); |
| } |
| return err >= 0 ? 0 : -1; |
| } |
| |
| char *synthesize_probe_trace_command(struct probe_trace_event *tev) |
| { |
| struct probe_trace_point *tp = &tev->point; |
| struct strbuf buf; |
| char *ret = NULL; |
| int i, err; |
| |
| /* Uprobes must have tp->module */ |
| if (tev->uprobes && !tp->module) |
| return NULL; |
| |
| if (strbuf_init(&buf, 32) < 0) |
| return NULL; |
| |
| if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p', |
| tev->group, tev->event) < 0) |
| goto error; |
| /* |
| * If tp->address == 0, then this point must be a |
| * absolute address uprobe. |
| * try_to_find_absolute_address() should have made |
| * tp->symbol to "0x0". |
| */ |
| if (tev->uprobes && !tp->address) { |
| if (!tp->symbol || strcmp(tp->symbol, "0x0")) |
| goto error; |
| } |
| |
| /* Use the tp->address for uprobes */ |
| if (tev->uprobes) { |
| err = synthesize_uprobe_trace_def(tev, &buf); |
| } else if (!strncmp(tp->symbol, "0x", 2)) { |
| /* Absolute address. See try_to_find_absolute_address() */ |
| err = strbuf_addf(&buf, "%s%s0x%lx", tp->module ?: "", |
| tp->module ? ":" : "", tp->address); |
| } else { |
| err = strbuf_addf(&buf, "%s%s%s+%lu", tp->module ?: "", |
| tp->module ? ":" : "", tp->symbol, tp->offset); |
| } |
| |
| if (err) |
| goto error; |
| |
| for (i = 0; i < tev->nargs; i++) |
| if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0) |
| goto error; |
| |
| ret = strbuf_detach(&buf, NULL); |
| error: |
| strbuf_release(&buf); |
| return ret; |
| } |
| |
| 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 = NULL; |
| u64 addr = tp->address; |
| int ret = -ENOENT; |
| |
| if (!is_kprobe) { |
| map = dso__new_map(tp->module); |
| if (!map) |
| goto out; |
| sym = map__find_symbol(map, addr); |
| } else { |
| if (tp->symbol && !addr) { |
| if (kernel_get_symbol_address_by_name(tp->symbol, |
| &addr, true, false) < 0) |
| goto out; |
| } |
| if (addr) { |
| addr += tp->offset; |
| sym = machine__find_kernel_symbol(host_machine, 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__put(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 { |
| 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) |
| { |
| struct strbuf buf = STRBUF_INIT; |
| 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 { |
| if ((ret = strbuf_init(&buf, 32)) < 0) |
| goto error; |
| ret = synthesize_probe_trace_arg(&tev->args[i], &buf); |
| pev->args[i].name = strbuf_detach(&buf, NULL); |
| } |
| if (pev->args[i].name == NULL && ret >= 0) |
| ret = -ENOMEM; |
| } |
| error: |
| 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; |
| |
| zfree(&pev->event); |
| zfree(&pev->group); |
| zfree(&pev->target); |
| clear_perf_probe_point(&pev->point); |
| |
| for (i = 0; i < pev->nargs; i++) { |
| zfree(&pev->args[i].name); |
| zfree(&pev->args[i].var); |
| zfree(&pev->args[i].type); |
| field = pev->args[i].field; |
| while (field) { |
| next = field->next; |
| zfree(&field->name); |
| free(field); |
| field = next; |
| } |
| } |
| pev->nargs = 0; |
| zfree(&pev->args); |
| } |
| |
| #define strdup_or_goto(str, label) \ |
| ({ char *__p = NULL; if (str && !(__p = strdup(str))) goto label; __p; }) |
| |
| static int perf_probe_point__copy(struct perf_probe_point *dst, |
| struct perf_probe_point *src) |
| { |
| dst->file = strdup_or_goto(src->file, out_err); |
| dst->function = strdup_or_goto(src->function, out_err); |
| dst->lazy_line = strdup_or_goto(src->lazy_line, out_err); |
| dst->line = src->line; |
| dst->retprobe = src->retprobe; |
| dst->offset = src->offset; |
| return 0; |
| |
| out_err: |
| clear_perf_probe_point(dst); |
| return -ENOMEM; |
| } |
| |
| static int perf_probe_arg__copy(struct perf_probe_arg *dst, |
| struct perf_probe_arg *src) |
| { |
| struct perf_probe_arg_field *field, **ppfield; |
| |
| dst->name = strdup_or_goto(src->name, out_err); |
| dst->var = strdup_or_goto(src->var, out_err); |
| dst->type = strdup_or_goto(src->type, out_err); |
| |
| field = src->field; |
| ppfield = &(dst->field); |
| while (field) { |
| *ppfield = zalloc(sizeof(*field)); |
| if (!*ppfield) |
| goto out_err; |
| (*ppfield)->name = strdup_or_goto(field->name, out_err); |
| (*ppfield)->index = field->index; |
| (*ppfield)->ref = field->ref; |
| field = field->next; |
| ppfield = &((*ppfield)->next); |
| } |
| return 0; |
| out_err: |
| return -ENOMEM; |
| } |
| |
| int perf_probe_event__copy(struct perf_probe_event *dst, |
| struct perf_probe_event *src) |
| { |
| int i; |
| |
| dst->event = strdup_or_goto(src->event, out_err); |
| dst->group = strdup_or_goto(src->group, out_err); |
| dst->target = strdup_or_goto(src->target, out_err); |
| dst->uprobes = src->uprobes; |
| |
| if (perf_probe_point__copy(&dst->point, &src->point) < 0) |
| goto out_err; |
| |
| dst->args = zalloc(sizeof(struct perf_probe_arg) * src->nargs); |
| if (!dst->args) |
| goto out_err; |
| dst->nargs = src->nargs; |
| |
| for (i = 0; i < src->nargs; i++) |
| if (perf_probe_arg__copy(&dst->args[i], &src->args[i]) < 0) |
| goto out_err; |
| return 0; |
| |
| out_err: |
| clear_perf_probe_event(dst); |
| return -ENOMEM; |
| } |
| |
| void clear_probe_trace_event(struct probe_trace_event *tev) |
| { |
| struct probe_trace_arg_ref *ref, *next; |
| int i; |
| |
| zfree(&tev->event); |
| zfree(&tev->group); |
| zfree(&tev->point.symbol); |
| zfree(&tev->point.realname); |
| zfree(&tev->point.module); |
| for (i = 0; i < tev->nargs; i++) { |
| zfree(&tev->args[i].name); |
| zfree(&tev->args[i].value); |
| zfree(&tev->args[i].type); |
| ref = tev->args[i].ref; |
| while (ref) { |
| next = ref->next; |
| free(ref); |
| ref = next; |
| } |
| } |
| zfree(&tev->args); |
| tev->nargs = 0; |
| } |
| |
| 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_init(&node->list); |
| zfree(&node->symbol); |
| free(node); |
| } |
| } |
| |
| static int kprobe_blacklist__load(struct list_head *blacklist) |
| { |
| struct kprobe_blacklist_node *node; |
| const char *__debugfs = debugfs__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; |
| } |
| |
| static LIST_HEAD(kprobe_blacklist); |
| |
| static void kprobe_blacklist__init(void) |
| { |
| if (!list_empty(&kprobe_blacklist)) |
| return; |
| |
| if (kprobe_blacklist__load(&kprobe_blacklist) < 0) |
| pr_debug("No kprobe blacklist support, ignored\n"); |
| } |
| |
| static void kprobe_blacklist__release(void) |
| { |
| kprobe_blacklist__delete(&kprobe_blacklist); |
| } |
| |
| static bool kprobe_blacklist__listed(unsigned long address) |
| { |
| return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address); |
| } |
| |
| static int perf_probe_event__sprintf(const char *group, const char *event, |
| struct perf_probe_event *pev, |
| const char *module, |
| struct strbuf *result) |
| { |
| int i, ret; |
| char *buf; |
| |
| if (asprintf(&buf, "%s:%s", group, event) < 0) |
| return -errno; |
| ret = strbuf_addf(result, " %-20s (on ", buf); |
| free(buf); |
| if (ret) |
| return ret; |
| |
| /* Synthesize only event probe point */ |
| buf = synthesize_perf_probe_point(&pev->point); |
| if (!buf) |
| return -ENOMEM; |
| ret = strbuf_addstr(result, buf); |
| free(buf); |
| |
| if (!ret && module) |
| ret = strbuf_addf(result, " in %s", module); |
| |
| if (!ret && pev->nargs > 0) { |
| ret = strbuf_add(result, " with", 5); |
| for (i = 0; !ret && i < pev->nargs; i++) { |
| buf = synthesize_perf_probe_arg(&pev->args[i]); |
| if (!buf) |
| return -ENOMEM; |
| ret = strbuf_addf(result, " %s", buf); |
| free(buf); |
| } |
| } |
| if (!ret) |
| ret = strbuf_addch(result, ')'); |
| |
| return ret; |
| } |
| |
| /* Show an event */ |
| int show_perf_probe_event(const char *group, const char *event, |
| struct perf_probe_event *pev, |
| const char *module, bool use_stdout) |
| { |
| struct strbuf buf = STRBUF_INIT; |
| int ret; |
| |
| ret = perf_probe_event__sprintf(group, event, pev, module, &buf); |
| if (ret >= 0) { |
| if (use_stdout) |
| printf("%s\n", buf.buf); |
| else |
| pr_info("%s\n", buf.buf); |
| } |
| strbuf_release(&buf); |
| |
| 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 = probe_file__get_rawlist(fd); |
| if (!rawlist) |
| return -ENOMEM; |
| |
| strlist__for_each_entry(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) |
| goto next; |
| ret = show_perf_probe_event(pev.group, pev.event, |
| &pev, tev.point.module, |
| true); |
| } |
| next: |
| clear_perf_probe_event(&pev); |
| clear_probe_trace_event(&tev); |
| if (ret < 0) |
| break; |
| } |
| strlist__delete(rawlist); |
| /* Cleanup cached debuginfo if needed */ |
| debuginfo_cache__exit(); |
| |
| return ret; |
| } |
| |
| /* List up current perf-probe events */ |
| int show_perf_probe_events(struct strfilter *filter) |
| { |
| int kp_fd, up_fd, ret; |
| |
| setup_pager(); |
| |
| if (probe_conf.cache) |
| return probe_cache__show_all_caches(filter); |
| |
| ret = init_probe_symbol_maps(false); |
| if (ret < 0) |
| return ret; |
| |
| ret = probe_file__open_both(&kp_fd, &up_fd, 0); |
| if (ret < 0) |
| return ret; |
| |
| if (kp_fd >= 0) |
| ret = __show_perf_probe_events(kp_fd, true, filter); |
| if (up_fd >= 0 && ret >= 0) |
| ret = __show_perf_probe_events(up_fd, false, filter); |
| if (kp_fd > 0) |
| close(kp_fd); |
| if (up_fd > 0) |
| close(up_fd); |
| exit_probe_symbol_maps(); |
| |
| return ret; |
| } |
| |
| static int get_new_event_name(char *buf, size_t len, const char *base, |
| struct strlist *namelist, bool ret_event, |
| bool allow_suffix) |
| { |
| int i, ret; |
| char *p, *nbase; |
| |
| if (*base == '.') |
| base++; |
| nbase = strdup(base); |
| if (!nbase) |
| return -ENOMEM; |
| |
| /* Cut off the dot suffixes (e.g. .const, .isra) and version suffixes */ |
| p = strpbrk(nbase, ".@"); |
| if (p && p != nbase) |
| *p = '\0'; |
| |
| /* Try no suffix number */ |
| ret = e_snprintf(buf, len, "%s%s", nbase, ret_event ? "__return" : ""); |
| if (ret < 0) { |
| pr_debug("snprintf() failed: %d\n", ret); |
| goto out; |
| } |
| if (!strlist__has_entry(namelist, buf)) |
| goto out; |
| |
| if (!allow_suffix) { |
| pr_warning("Error: event \"%s\" already exists.\n" |
| " Hint: Remove existing event by 'perf probe -d'\n" |
| " or force duplicates by 'perf probe -f'\n" |
| " or set 'force=yes' in BPF source.\n", |
| buf); |
| ret = -EEXIST; |
| goto out; |
| } |
| |
| /* Try to add suffix */ |
| for (i = 1; i < MAX_EVENT_INDEX; i++) { |
| ret = e_snprintf(buf, len, "%s_%d", nbase, i); |
| if (ret < 0) { |
| pr_debug("snprintf() failed: %d\n", ret); |
| goto out; |
| } |
| 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; |
| } |
| |
| out: |
| free(nbase); |
| |
| /* Final validation */ |
| if (ret >= 0 && !is_c_func_name(buf)) { |
| pr_warning("Internal error: \"%s\" is an invalid event name.\n", |
| buf); |
| ret = -EINVAL; |
| } |
| |
| 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); |
| struct probe_trace_point *tp = &tev->point; |
| |
| if (tp->ref_ctr_offset && !uprobe_ref_ctr_is_supported()) { |
| pr_warning("A semaphore is associated with %s:%s and " |
| "seems your kernel doesn't support it.\n", |
| tev->group, tev->event); |
| } |
| |
| /* 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); |
| } |
| |
| /* Set new name from original perf_probe_event and namelist */ |
| static int probe_trace_event__set_name(struct probe_trace_event *tev, |
| struct perf_probe_event *pev, |
| struct strlist *namelist, |
| bool allow_suffix) |
| { |
| const char *event, *group; |
| char buf[64]; |
| int ret; |
| |
| /* If probe_event or trace_event already have the name, reuse it */ |
| if (pev->event && !pev->sdt) |
| event = pev->event; |
| else if (tev->event) |
| event = tev->event; |
| else { |
| /* Or generate new one from probe point */ |
| if (pev->point.function && |
| (strncmp(pev->point.function, "0x", 2) != 0) && |
| !strisglob(pev->point.function)) |
| event = pev->point.function; |
| else |
| event = tev->point.realname; |
| } |
| if (pev->group && !pev->sdt) |
| group = pev->group; |
| else if (tev->group) |
| group = tev->group; |
| else |
| group = PERFPROBE_GROUP; |
| |
| /* Get an unused new event name */ |
| ret = get_new_event_name(buf, 64, event, namelist, |
| tev->point.retprobe, allow_suffix); |
| if (ret < 0) |
| return ret; |
| |
| event = buf; |
| |
| tev->event = strdup(event); |
| tev->group = strdup(group); |
| if (tev->event == NULL || tev->group == NULL) |
| return -ENOMEM; |
| |
| /* Add added event name to namelist */ |
| strlist__add(namelist, event); |
| return 0; |
| } |
| |
| static int __open_probe_file_and_namelist(bool uprobe, |
| struct strlist **namelist) |
| { |
| int fd; |
| |
| fd = probe_file__open(PF_FL_RW | (uprobe ? PF_FL_UPROBE : 0)); |
| if (fd < 0) |
| return fd; |
| |
| /* Get current event names */ |
| *namelist = probe_file__get_namelist(fd); |
| if (!(*namelist)) { |
| pr_debug("Failed to get current event list.\n"); |
| close(fd); |
| return -ENOMEM; |
| } |
| return fd; |
| } |
| |
| static int __add_probe_trace_events(struct perf_probe_event *pev, |
| struct probe_trace_event *tevs, |
| int ntevs, bool allow_suffix) |
| { |
| int i, fd[2] = {-1, -1}, up, ret; |
| struct probe_trace_event *tev = NULL; |
| struct probe_cache *cache = NULL; |
| struct strlist *namelist[2] = {NULL, NULL}; |
| struct nscookie nsc; |
| |
| up = pev->uprobes ? 1 : 0; |
| fd[up] = __open_probe_file_and_namelist(up, &namelist[up]); |
| if (fd[up] < 0) |
| return fd[up]; |
| |
| ret = 0; |
| for (i = 0; i < ntevs; i++) { |
| tev = &tevs[i]; |
| up = tev->uprobes ? 1 : 0; |
| if (fd[up] == -1) { /* Open the kprobe/uprobe_events */ |
| fd[up] = __open_probe_file_and_namelist(up, |
| &namelist[up]); |
| if (fd[up] < 0) |
| goto close_out; |
| } |
| /* Skip if the symbol is out of .text or blacklisted */ |
| if (!tev->point.symbol && !pev->uprobes) |
| continue; |
| |
| /* Set new name for tev (and update namelist) */ |
| ret = probe_trace_event__set_name(tev, pev, namelist[up], |
| allow_suffix); |
| if (ret < 0) |
| break; |
| |
| nsinfo__mountns_enter(pev->nsi, &nsc); |
| ret = probe_file__add_event(fd[up], tev); |
| nsinfo__mountns_exit(&nsc); |
| if (ret < 0) |
| break; |
| |
| /* |
| * 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); |
| if (ret == 0 && probe_conf.cache) { |
| cache = probe_cache__new(pev->target, pev->nsi); |
| if (!cache || |
| probe_cache__add_entry(cache, pev, tevs, ntevs) < 0 || |
| probe_cache__commit(cache) < 0) |
| pr_warning("Failed to add event to probe cache\n"); |
| probe_cache__delete(cache); |
| } |
| |
| close_out: |
| for (up = 0; up < 2; up++) { |
| strlist__delete(namelist[up]); |
| if (fd[up] >= 0) |
| close(fd[up]); |
| } |
| return ret; |
| } |
| |
| static int find_probe_functions(struct map *map, char *name, |
| struct symbol **syms) |
| { |
| int found = 0; |
| struct symbol *sym; |
| struct rb_node *tmp; |
| const char *norm, *ver; |
| char *buf = NULL; |
| bool cut_version = true; |
| |
| if (map__load(map) < 0) |
| return 0; |
| |
| /* If user gives a version, don't cut off the version from symbols */ |
| if (strchr(name, '@')) |
| cut_version = false; |
| |
| map__for_each_symbol(map, sym, tmp) { |
| norm = arch__normalize_symbol_name(sym->name); |
| if (!norm) |
| continue; |
| |
| if (cut_version) { |
| /* We don't care about default symbol or not */ |
| ver = strchr(norm, '@'); |
| if (ver) { |
| buf = strndup(norm, ver - norm); |
| if (!buf) |
| return -ENOMEM; |
| norm = buf; |
| } |
| } |
| |
| if (strglobmatch(norm, name)) { |
| found++; |
| if (syms && found < probe_conf.max_probes) |
| syms[found - 1] = sym; |
| } |
| if (buf) |
| zfree(&buf); |
| } |
| |
| return found; |
| } |
| |
| 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, |
| struct symbol *sym __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 symbol **syms = NULL; |
| struct probe_trace_event *tev; |
| struct perf_probe_point *pp = &pev->point; |
| struct probe_trace_point *tp; |
| int num_matched_functions; |
| int ret, i, j, skipped = 0; |
| char *mod_name; |
| |
| map = get_target_map(pev->target, pev->nsi, pev->uprobes); |
| if (!map) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| syms = malloc(sizeof(struct symbol *) * probe_conf.max_probes); |
| if (!syms) { |
| ret = -ENOMEM; |
| 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, syms); |
| 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; |
| } |
|