diff options
Diffstat (limited to 'kernel/trace/trace_probe.c')
-rw-r--r-- | kernel/trace/trace_probe.c | 177 |
1 files changed, 151 insertions, 26 deletions
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index dbef0d135075..baf58a3612c0 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -316,6 +316,29 @@ inval_var: return -EINVAL; } +static int str_to_immediate(char *str, unsigned long *imm) +{ + if (isdigit(str[0])) + return kstrtoul(str, 0, imm); + else if (str[0] == '-') + return kstrtol(str, 0, (long *)imm); + else if (str[0] == '+') + return kstrtol(str + 1, 0, (long *)imm); + return -EINVAL; +} + +static int __parse_imm_string(char *str, char **pbuf, int offs) +{ + size_t len = strlen(str); + + if (str[len - 1] != '"') { + trace_probe_log_err(offs + len, IMMSTR_NO_CLOSE); + return -EINVAL; + } + *pbuf = kstrndup(str, len - 1, GFP_KERNEL); + return 0; +} + /* Recursive argument parser */ static int parse_probe_arg(char *arg, const struct fetch_type *type, @@ -430,7 +453,8 @@ parse_probe_arg(char *arg, const struct fetch_type *type, ret = parse_probe_arg(arg, t2, &code, end, flags, offs); if (ret) break; - if (code->op == FETCH_OP_COMM) { + if (code->op == FETCH_OP_COMM || + code->op == FETCH_OP_DATA) { trace_probe_log_err(offs, COMM_CANT_DEREF); return -EINVAL; } @@ -444,6 +468,21 @@ parse_probe_arg(char *arg, const struct fetch_type *type, code->offset = offset; } break; + case '\\': /* Immediate value */ + if (arg[1] == '"') { /* Immediate string */ + ret = __parse_imm_string(arg + 2, &tmp, offs + 2); + if (ret) + break; + code->op = FETCH_OP_DATA; + code->data = tmp; + } else { + ret = str_to_immediate(arg + 1, &code->immediate); + if (ret) + trace_probe_log_err(offs + 1, BAD_IMM); + else + code->op = FETCH_OP_IMM; + } + break; } if (!ret && code->op == FETCH_OP_NOP) { /* Parsed, but do not find fetch method */ @@ -542,8 +581,11 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size, } } - /* Since $comm can not be dereferred, we can find $comm by strcmp */ - if (strcmp(arg, "$comm") == 0) { + /* + * Since $comm and immediate string can not be dereferred, + * we can find those by strcmp. + */ + if (strcmp(arg, "$comm") == 0 || strncmp(arg, "\\\"", 2) == 0) { /* The type of $comm must be "string", and not an array. */ if (parg->count || (t && strcmp(t, "string"))) return -EINVAL; @@ -580,7 +622,8 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size, if (!strcmp(parg->type->name, "string") || !strcmp(parg->type->name, "ustring")) { if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF && - code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM) { + code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM && + code->op != FETCH_OP_DATA) { trace_probe_log_err(offset + (t ? (t - arg) : 0), BAD_STRING); ret = -EINVAL; @@ -589,9 +632,10 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size, if ((code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM) || parg->count) { /* - * IMM and COMM is pointing actual address, those must - * be kept, and if parg->count != 0, this is an array - * of string pointers instead of string address itself. + * IMM, DATA and COMM is pointing actual address, those + * must be kept, and if parg->count != 0, this is an + * array of string pointers instead of string address + * itself. */ code++; if (code->op != FETCH_OP_NOP) { @@ -665,7 +709,8 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size, fail: if (ret) { for (code = tmp; code < tmp + FETCH_INSN_MAX; code++) - if (code->op == FETCH_NOP_SYMBOL) + if (code->op == FETCH_NOP_SYMBOL || + code->op == FETCH_OP_DATA) kfree(code->data); } kfree(tmp); @@ -736,7 +781,8 @@ void traceprobe_free_probe_arg(struct probe_arg *arg) struct fetch_insn *code = arg->code; while (code && code->op != FETCH_OP_END) { - if (code->op == FETCH_NOP_SYMBOL) + if (code->op == FETCH_NOP_SYMBOL || + code->op == FETCH_OP_DATA) kfree(code->data); code++; } @@ -886,43 +932,85 @@ int traceprobe_define_arg_fields(struct trace_event_call *event_call, return 0; } +static void trace_probe_event_free(struct trace_probe_event *tpe) +{ + kfree(tpe->class.system); + kfree(tpe->call.name); + kfree(tpe->call.print_fmt); + kfree(tpe); +} + +int trace_probe_append(struct trace_probe *tp, struct trace_probe *to) +{ + if (trace_probe_has_sibling(tp)) + return -EBUSY; + + list_del_init(&tp->list); + trace_probe_event_free(tp->event); + + tp->event = to->event; + list_add_tail(&tp->list, trace_probe_probe_list(to)); + + return 0; +} + +void trace_probe_unlink(struct trace_probe *tp) +{ + list_del_init(&tp->list); + if (list_empty(trace_probe_probe_list(tp))) + trace_probe_event_free(tp->event); + tp->event = NULL; +} void trace_probe_cleanup(struct trace_probe *tp) { - struct trace_event_call *call = trace_probe_event_call(tp); int i; for (i = 0; i < tp->nr_args; i++) traceprobe_free_probe_arg(&tp->args[i]); - kfree(call->class->system); - kfree(call->name); - kfree(call->print_fmt); + if (tp->event) + trace_probe_unlink(tp); } int trace_probe_init(struct trace_probe *tp, const char *event, const char *group) { - struct trace_event_call *call = trace_probe_event_call(tp); + struct trace_event_call *call; + int ret = 0; if (!event || !group) return -EINVAL; - call->class = &tp->class; - call->name = kstrdup(event, GFP_KERNEL); - if (!call->name) + tp->event = kzalloc(sizeof(struct trace_probe_event), GFP_KERNEL); + if (!tp->event) return -ENOMEM; - tp->class.system = kstrdup(group, GFP_KERNEL); - if (!tp->class.system) { - kfree(call->name); - call->name = NULL; - return -ENOMEM; + INIT_LIST_HEAD(&tp->event->files); + INIT_LIST_HEAD(&tp->event->class.fields); + INIT_LIST_HEAD(&tp->event->probes); + INIT_LIST_HEAD(&tp->list); + list_add(&tp->event->probes, &tp->list); + + call = trace_probe_event_call(tp); + call->class = &tp->event->class; + call->name = kstrdup(event, GFP_KERNEL); + if (!call->name) { + ret = -ENOMEM; + goto error; + } + + tp->event->class.system = kstrdup(group, GFP_KERNEL); + if (!tp->event->class.system) { + ret = -ENOMEM; + goto error; } - INIT_LIST_HEAD(&tp->files); - INIT_LIST_HEAD(&tp->class.fields); return 0; + +error: + trace_probe_cleanup(tp); + return ret; } int trace_probe_register_event_call(struct trace_probe *tp) @@ -951,7 +1039,7 @@ int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file) link->file = file; INIT_LIST_HEAD(&link->list); - list_add_tail_rcu(&link->list, &tp->files); + list_add_tail_rcu(&link->list, &tp->event->files); trace_probe_set_flag(tp, TP_FLAG_TRACE); return 0; } @@ -982,8 +1070,45 @@ int trace_probe_remove_file(struct trace_probe *tp, synchronize_rcu(); kfree(link); - if (list_empty(&tp->files)) + if (list_empty(&tp->event->files)) trace_probe_clear_flag(tp, TP_FLAG_TRACE); return 0; } + +/* + * Return the smallest index of different type argument (start from 1). + * If all argument types and name are same, return 0. + */ +int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b) +{ + int i; + + for (i = 0; i < a->nr_args; i++) { + if ((b->nr_args <= i) || + ((a->args[i].type != b->args[i].type) || + (a->args[i].count != b->args[i].count) || + strcmp(a->args[i].name, b->args[i].name))) + return i + 1; + } + + return 0; +} + +bool trace_probe_match_command_args(struct trace_probe *tp, + int argc, const char **argv) +{ + char buf[MAX_ARGSTR_LEN + 1]; + int i; + + if (tp->nr_args < argc) + return false; + + for (i = 0; i < argc; i++) { + snprintf(buf, sizeof(buf), "%s=%s", + tp->args[i].name, tp->args[i].comm); + if (strcmp(buf, argv[i])) + return false; + } + return true; +} |