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charset="utf-8" Set up beauty_map, load it to BPF, in such format: if argument No.3 is a struct of size 32 bytes (of syscall number 114) beauty_map[114][2] =3D 32; if argument No.3 is a string (of syscall number 114) beauty_map[114][2] =3D 1; if argument No.3 is a buffer, its size is indicated by argument No.4 (of sy= scall number 114) beauty_map[114][2] =3D -4; /* -1 ~ -6, we'll read this buffer size in BPF = */ Add type_id member to syscall_arg_fmt because it is required by btf_dump. Add syscall_arg__scnprintf_buf() to pretty print augmented buffer. Use btf_dump API to pretty print augmented struct pointer. Add trace__init_pid_filter(), to set up pid_filter before running BPF program. This way, we don't accidentally collect augmented data from processes we don't care about. Signed-off-by: Howard Chu --- tools/perf/builtin-trace.c | 254 ++++++++++++++++++++++++++++++++++++- 1 file changed, 250 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 8af93a2f0bcd..cf52fda453e0 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -113,6 +113,7 @@ struct syscall_arg_fmt { bool show_zero; #ifdef HAVE_LIBBPF_SUPPORT const struct btf_type *type; + int type_id; #endif }; =20 @@ -851,6 +852,11 @@ static size_t syscall_arg__scnprintf_filename(char *bf= , size_t size, =20 #define SCA_FILENAME syscall_arg__scnprintf_filename =20 +static size_t syscall_arg__scnprintf_buf(char *bf, size_t size, + struct syscall_arg *arg); + +#define SCA_BUF syscall_arg__scnprintf_buf + static size_t syscall_arg__scnprintf_pipe_flags(char *bf, size_t size, struct syscall_arg *arg) { @@ -930,6 +936,24 @@ static void syscall_arg_fmt__cache_btf_enum(struct sys= call_arg_fmt *arg_fmt, str arg_fmt->type =3D btf__type_by_id(btf, id); } =20 +static int syscall_arg_fmt__cache_btf_struct(struct syscall_arg_fmt *arg_f= mt, struct btf *btf, char *type) +{ + /* this function is solely used in trace__bpf_sys_enter_beauty_map */ + int id; + + if (arg_fmt->type !=3D NULL) + return -1; + + id =3D btf__find_by_name(btf, type); + if (id < 0) + return -1; + + arg_fmt->type_id =3D id; /* used for dumping data later */ + arg_fmt->type =3D btf__type_by_id(btf, id); + + return 0; +} + static bool syscall_arg__strtoul_btf_enum(char *bf, size_t size, struct sy= scall_arg *arg, u64 *val) { const struct btf_type *bt =3D arg->fmt->type; @@ -991,8 +1015,56 @@ static size_t btf_enum_scnprintf(const struct btf_typ= e *type, struct btf *btf, c return 0; } =20 +#define DUMPSIZ 256 + +static void btf_dump_snprintf(void *ctx, const char *fmt, va_list args) +{ + char *s =3D ctx, new[DUMPSIZ]; + + vsnprintf(new, DUMPSIZ, fmt, args); + + if (strlen(s) + strlen(new) < DUMPSIZ) + strncat(s, new, DUMPSIZ); +} + +static size_t btf_dump__struct_scnprintf(const struct btf_type *type, stru= ct btf *btf, char *bf, size_t size, struct syscall_arg *arg, int type_id) +{ + char str[DUMPSIZ]; + int dump_size; + int consumed; + struct btf_dump *btf_dump; + struct augmented_arg *augmented_arg =3D arg->augmented.args; + LIBBPF_OPTS(btf_dump_opts, dump_opts); + LIBBPF_OPTS(btf_dump_type_data_opts, dump_data_opts); + + if (arg =3D=3D NULL || arg->augmented.args =3D=3D NULL) + return 0; + + memset(str, 0, sizeof(str)); + + dump_data_opts.compact =3D true; + dump_data_opts.skip_names =3D true; + + btf_dump =3D btf_dump__new(btf, btf_dump_snprintf, str, &dump_opts); + if (btf_dump =3D=3D NULL) + return 0; + + consumed =3D sizeof(*augmented_arg) + augmented_arg->size; + + dump_size =3D btf_dump__dump_type_data(btf_dump, type_id, arg->augmented.= args->value, type->size, &dump_data_opts); + if (dump_size =3D=3D 0) + return 0; + + arg->augmented.args =3D ((void *)arg->augmented.args) + consumed; + arg->augmented.size -=3D consumed; + + btf_dump__free(btf_dump); + + return scnprintf(bf, size, "%s", str); +} + static size_t trace__btf_scnprintf(struct trace *trace, struct syscall_arg= _fmt *arg_fmt, char *bf, - size_t size, int val, char *type) + size_t size, int val, struct syscall_arg *arg, char *type) { if (trace->btf =3D=3D NULL) return 0; @@ -1008,6 +1080,8 @@ static size_t trace__btf_scnprintf(struct trace *trac= e, struct syscall_arg_fmt * =20 if (btf_is_enum(arg_fmt->type)) return btf_enum_scnprintf(arg_fmt->type, trace->btf, bf, size, val); + else if (btf_is_struct(arg_fmt->type)) + return btf_dump__struct_scnprintf(arg_fmt->type, trace->btf, bf, size, a= rg, arg_fmt->type_id); =20 return 0; } @@ -1694,6 +1768,53 @@ static size_t syscall_arg__scnprintf_filename(char *= bf, size_t size, return 0; } =20 +#define MAX_CONTROL_CHAR 31 +#define MAX_ASCII 127 +#define MAX_BUF 32 + +static size_t syscall_arg__scnprintf_augmented_buf(struct syscall_arg *arg= , char *bf, size_t size) +{ + struct augmented_arg *augmented_arg =3D arg->augmented.args; + size_t printed =3D 0; + unsigned char *start =3D (unsigned char *)augmented_arg->value; + int i =3D 0, n =3D augmented_arg->size, consumed, digits; + char tmp[MAX_BUF * 4], tens[4]; + + memset(tmp, 0, sizeof(tmp)); + + for (int j =3D 0; j < n && i < (int)sizeof(tmp); ++j) { + /* print control characters(0~31 and 127), and characters bigger than 12= 7 in \ */ + if (start[j] <=3D MAX_CONTROL_CHAR || start[j] > MAX_ASCII) { + tmp[i++] =3D '\\'; + digits =3D scnprintf(tens, sizeof(tmp) - i, "%d", (int)start[j]); + if (digits + i <=3D (int)sizeof(tmp)) { + strncpy(tmp + i, tens, digits); + i +=3D digits; + } + } else { + tmp[i++] =3D start[j]; + } + } + + printed =3D scnprintf(bf, size, "\"%s\"", tmp); + + consumed =3D sizeof(*augmented_arg) + augmented_arg->size; + + arg->augmented.args =3D ((void *)arg->augmented.args) + consumed; + arg->augmented.size -=3D consumed; + + return printed; +} + +static size_t syscall_arg__scnprintf_buf(char *bf, size_t size, + struct syscall_arg *arg) +{ + if (arg->augmented.args) + return syscall_arg__scnprintf_augmented_buf(arg, bf, size); + + return 0; +} + static bool trace__filter_duration(struct trace *trace, double t) { return t < (trace->duration_filter * NSEC_PER_MSEC); @@ -1903,8 +2024,16 @@ syscall_arg_fmt__init_array(struct syscall_arg_fmt *= arg, struct tep_format_field =20 if (strcmp(field->type, "const char *") =3D=3D 0 && ((len >=3D 4 && strcmp(field->name + len - 4, "name") =3D=3D 0) || - strstr(field->name, "path") !=3D NULL)) + strstr(field->name, "path") || + strstr(field->name, "file") || + strstr(field->name, "root") || + strstr(field->name, "key") || + strstr(field->name, "special") || + strstr(field->name, "type") || + strstr(field->name, "description"))) arg->scnprintf =3D SCA_FILENAME; + else if (strstr(field->type, "char *") && strstr(field->name, "buf")) + arg->scnprintf =3D SCA_BUF; else if ((field->flags & TEP_FIELD_IS_POINTER) || strstr(field->name, "a= ddr")) arg->scnprintf =3D SCA_PTR; else if (strcmp(field->type, "pid_t") =3D=3D 0) @@ -2263,7 +2392,7 @@ static size_t syscall__scnprintf_args(struct syscall = *sc, char *bf, size_t size, printed +=3D scnprintf(bf + printed, size - printed, "%s: ", field->na= me); =20 btf_printed =3D trace__btf_scnprintf(trace, &sc->arg_fmt[arg.idx], bf += printed, - size - printed, val, field->type); + size - printed, val, &arg, field->type); if (btf_printed) { printed +=3D btf_printed; continue; @@ -2965,7 +3094,7 @@ static size_t trace__fprintf_tp_fields(struct trace *= trace, struct evsel *evsel, if (trace->show_arg_names) printed +=3D scnprintf(bf + printed, size - printed, "%s: ", field->nam= e); =20 - btf_printed =3D trace__btf_scnprintf(trace, arg, bf + printed, size - pr= inted, val, field->type); + btf_printed =3D trace__btf_scnprintf(trace, arg, bf + printed, size - pr= inted, val, NULL, field->type); if (btf_printed) { printed +=3D btf_printed; continue; @@ -3523,6 +3652,82 @@ static int trace__bpf_prog_sys_exit_fd(struct trace = *trace, int id) return sc ? bpf_program__fd(sc->bpf_prog.sys_exit) : bpf_program__fd(trac= e->skel->progs.syscall_unaugmented); } =20 +static int trace__bpf_sys_enter_beauty_map(struct trace *trace, int key, u= nsigned int *beauty_array) +{ + struct tep_format_field *field; + struct syscall *sc =3D trace__syscall_info(trace, NULL, key); + const struct btf_type *bt; + char *struct_offset, *tmp, name[32]; + bool augmented =3D false; + int i, cnt; + + if (sc =3D=3D NULL) + return -1; + + trace__load_vmlinux_btf(trace); + if (trace->btf =3D=3D NULL) + return -1; + + for (i =3D 0, field =3D sc->args; field; ++i, field =3D field->next) { + struct_offset =3D strstr(field->type, "struct "); + + if (field->flags & TEP_FIELD_IS_POINTER && struct_offset) { /* struct */ + struct_offset +=3D 7; + + /* for 'struct foo *', we only want 'foo' */ + for (tmp =3D struct_offset, cnt =3D 0; *tmp !=3D ' ' && *tmp !=3D '\0';= ++tmp, ++cnt) { + } + + strncpy(name, struct_offset, cnt); + name[cnt] =3D '\0'; + + if (syscall_arg_fmt__cache_btf_struct(&sc->arg_fmt[i], trace->btf, name= )) + continue; + + bt =3D sc->arg_fmt[i].type; + beauty_array[i] =3D bt->size; + augmented =3D true; + } else if (field->flags & TEP_FIELD_IS_POINTER && /* string */ + strcmp(field->type, "const char *") =3D=3D 0 && + (strstr(field->name, "name") || + strstr(field->name, "path") || + strstr(field->name, "file") || + strstr(field->name, "root") || + strstr(field->name, "key") || + strstr(field->name, "special") || + strstr(field->name, "type") || + strstr(field->name, "description"))) { + beauty_array[i] =3D 1; + augmented =3D true; + } else if (field->flags & TEP_FIELD_IS_POINTER && /* buffer */ + strstr(field->type, "char *") && + (strstr(field->name, "buf") || + strstr(field->name, "val") || + strstr(field->name, "msg"))) { + int j; + struct tep_format_field *field_tmp; + + /* find the size of the buffer */ + for (j =3D 0, field_tmp =3D sc->args; field_tmp; ++j, field_tmp =3D fie= ld_tmp->next) { + if (!(field_tmp->flags & TEP_FIELD_IS_POINTER) && /* only integers */ + (strstr(field_tmp->name, "count") || + strstr(field_tmp->name, "siz") || /* size, bufsiz */ + (strstr(field_tmp->name, "len") && strcmp(field_tmp->name, "filen= ame")))) { + /* filename's got 'len' in it, we don't want that */ + beauty_array[i] =3D -(j + 1); + augmented =3D true; + break; + } + } + } + } + + if (augmented) + return 0; + + return -1; +} + static struct bpf_program *trace__find_usable_bpf_prog_entry(struct trace = *trace, struct syscall *sc) { struct tep_format_field *field, *candidate_field; @@ -3627,7 +3832,9 @@ static int trace__init_syscalls_bpf_prog_array_maps(s= truct trace *trace) { int map_enter_fd =3D bpf_map__fd(trace->skel->maps.syscalls_sys_enter); int map_exit_fd =3D bpf_map__fd(trace->skel->maps.syscalls_sys_exit); + int beauty_map_fd =3D bpf_map__fd(trace->skel->maps.beauty_map_enter); int err =3D 0; + unsigned int beauty_array[6]; =20 for (int i =3D 0; i < trace->sctbl->syscalls.nr_entries; ++i) { int prog_fd, key =3D syscalltbl__id_at_idx(trace->sctbl, i); @@ -3646,6 +3853,15 @@ static int trace__init_syscalls_bpf_prog_array_maps(= struct trace *trace) err =3D bpf_map_update_elem(map_exit_fd, &key, &prog_fd, BPF_ANY); if (err) break; + + /* set up the size of struct pointer argument for beauty map */ + memset(beauty_array, 0, sizeof(beauty_array)); + err =3D trace__bpf_sys_enter_beauty_map(trace, key, (unsigned int *)beau= ty_array); + if (err) + continue; + err =3D bpf_map_update_elem(beauty_map_fd, &key, beauty_array, BPF_ANY); + if (err) + break; } =20 /* @@ -3714,6 +3930,33 @@ static int trace__init_syscalls_bpf_prog_array_maps(= struct trace *trace) =20 return err; } + +static void trace__init_pid_filter(struct trace *trace) +{ + int pid_filter_fd =3D bpf_map__fd(trace->skel->maps.pid_filter); + bool exists =3D true; + struct str_node *pos; + struct strlist *pid_slist =3D strlist__new(trace->opts.target.pid, NULL); + + trace->skel->bss->filter_pid =3D false; + + if (pid_slist) { + strlist__for_each_entry(pos, pid_slist) { + char *end_ptr; + int pid =3D strtol(pos->s, &end_ptr, 10); + + if (pid =3D=3D INT_MIN || pid =3D=3D INT_MAX || + (*end_ptr !=3D '\0' && *end_ptr !=3D ',')) + continue; + + bpf_map_update_elem(pid_filter_fd, &pid, &exists, BPF_ANY); + trace->skel->bss->filter_pid =3D true; + } + } + + strlist__delete(pid_slist); +} + #endif // HAVE_BPF_SKEL =20 static int trace__set_ev_qualifier_filter(struct trace *trace) @@ -4108,6 +4351,9 @@ static int trace__run(struct trace *trace, int argc, = const char **argv) #ifdef HAVE_BPF_SKEL if (trace->skel && trace->skel->progs.sys_enter) trace__init_syscalls_bpf_prog_array_maps(trace); + + if (trace->skel) + trace__init_pid_filter(trace); #endif =20 if (trace->ev_qualifier_ids.nr > 0) { --=20 2.45.2