From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Move trace event parameter fetching code to common parser in trace_probe.c. This simplifies eprobe's trace-event variable fetching code by introducing a parse context data structure. Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> --- kernel/trace/trace_eprobe.c | 44 +----------- kernel/trace/trace_fprobe.c | 4 + kernel/trace/trace_kprobe.c | 4 + kernel/trace/trace_probe.c | 156 ++++++++++++++++++++++++++----------------- kernel/trace/trace_probe.h | 9 ++ kernel/trace/trace_uprobe.c | 8 +- 6 files changed, 117 insertions(+), 108 deletions(-) diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index fd64cd5d5745..cb0077ba2b49 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -227,37 +227,6 @@ static struct trace_eprobe *alloc_event_probe(const char *group, return ERR_PTR(ret); } -static int trace_eprobe_tp_arg_update(struct trace_eprobe *ep, int i) -{ - struct probe_arg *parg = &ep->tp.args[i]; - struct ftrace_event_field *field; - struct list_head *head; - int ret = -ENOENT; - - head = trace_get_fields(ep->event); - list_for_each_entry(field, head, link) { - if (!strcmp(parg->code->data, field->name)) { - kfree(parg->code->data); - parg->code->data = field; - return 0; - } - } - - /* - * Argument not found on event. But allow for comm and COMM - * to be used to get the current->comm. - */ - if (strcmp(parg->code->data, "COMM") == 0 || - strcmp(parg->code->data, "comm") == 0) { - parg->code->op = FETCH_OP_COMM; - ret = 0; - } - - kfree(parg->code->data); - parg->code->data = NULL; - return ret; -} - static int eprobe_event_define_fields(struct trace_event_call *event_call) { struct eprobe_trace_entry_head field; @@ -817,19 +786,16 @@ find_and_get_event(const char *system, const char *event_name) static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[], int i) { - unsigned int flags = TPARG_FL_KERNEL | TPARG_FL_TEVENT; + struct traceprobe_parse_context ctx = { + .event = ep->event, + .flags = TPARG_FL_KERNEL | TPARG_FL_TEVENT, + }; int ret; - ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], flags); + ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], &ctx); if (ret) return ret; - if (ep->tp.args[i].code->op == FETCH_OP_TP_ARG) { - ret = trace_eprobe_tp_arg_update(ep, i); - if (ret) - trace_probe_log_err(0, BAD_ATTACH_ARG); - } - /* Handle symbols "@" */ if (!ret) ret = traceprobe_update_arg(&ep->tp.args[i]); diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 7c8be8a3616f..1dba45dfd234 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -1044,8 +1044,10 @@ static int __trace_fprobe_create(int argc, const char *argv[]) /* parse arguments */ for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct traceprobe_parse_context ctx = { .flags = flags }; + trace_probe_log_set_index(i + 2); - ret = traceprobe_parse_probe_arg(&tf->tp, i, argv[i], flags); + ret = traceprobe_parse_probe_arg(&tf->tp, i, argv[i], &ctx); if (ret) goto error; /* This can be -ENOMEM */ } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 38e34ed89d55..fd62de2a2f51 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -867,8 +867,10 @@ static int __trace_kprobe_create(int argc, const char *argv[]) /* parse arguments */ for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct traceprobe_parse_context ctx = { .flags = flags }; + trace_probe_log_set_index(i + 2); - ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], flags); + ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], &ctx); if (ret) goto error; /* This can be -ENOMEM */ } diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index dffbed2ddae9..84a9f0446390 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -283,27 +283,53 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup, return 0; } +static int parse_trace_event_arg(char *arg, struct fetch_insn *code, + struct traceprobe_parse_context *ctx) +{ + struct ftrace_event_field *field; + struct list_head *head; + + head = trace_get_fields(ctx->event); + list_for_each_entry(field, head, link) { + if (!strcmp(arg, field->name)) { + code->op = FETCH_OP_TP_ARG; + code->data = field; + return 0; + } + } + return -ENOENT; +} + #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) static int parse_probe_vars(char *arg, const struct fetch_type *t, - struct fetch_insn *code, unsigned int flags, int offs) + struct fetch_insn *code, + struct traceprobe_parse_context *ctx) { unsigned long param; int ret = 0; int len; - if (flags & TPARG_FL_TEVENT) { + if (ctx->flags & TPARG_FL_TEVENT) { if (code->data) return -EFAULT; - code->data = kstrdup(arg, GFP_KERNEL); - if (!code->data) - return -ENOMEM; - code->op = FETCH_OP_TP_ARG; - } else if (strcmp(arg, "retval") == 0) { - if (flags & TPARG_FL_RETURN) { + ret = parse_trace_event_arg(arg, code, ctx); + if (!ret) + return 0; + if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) { + code->op = FETCH_OP_COMM; + return 0; + } + /* backward compatibility */ + ctx->offset = 0; + goto inval_var; + } + + if (strcmp(arg, "retval") == 0) { + if (ctx->flags & TPARG_FL_RETURN) { code->op = FETCH_OP_RETVAL; } else { - trace_probe_log_err(offs, RETVAL_ON_PROBE); + trace_probe_log_err(ctx->offset, RETVAL_ON_PROBE); ret = -EINVAL; } } else if ((len = str_has_prefix(arg, "stack"))) { @@ -313,9 +339,9 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, ret = kstrtoul(arg + len, 10, ¶m); if (ret) { goto inval_var; - } else if ((flags & TPARG_FL_KERNEL) && + } else if ((ctx->flags & TPARG_FL_KERNEL) && param > PARAM_MAX_STACK) { - trace_probe_log_err(offs, BAD_STACK_NUM); + trace_probe_log_err(ctx->offset, BAD_STACK_NUM); ret = -EINVAL; } else { code->op = FETCH_OP_STACK; @@ -326,13 +352,13 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, } else if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) { code->op = FETCH_OP_COMM; #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API - } else if (tparg_is_function_entry(flags) && + } else if (tparg_is_function_entry(ctx->flags) && (len = str_has_prefix(arg, "arg"))) { ret = kstrtoul(arg + len, 10, ¶m); if (ret) { goto inval_var; } else if (!param || param > PARAM_MAX_STACK) { - trace_probe_log_err(offs, BAD_ARG_NUM); + trace_probe_log_err(ctx->offset, BAD_ARG_NUM); return -EINVAL; } code->op = FETCH_OP_ARG; @@ -341,7 +367,7 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, * The tracepoint probe will probe a stub function, and the * first parameter of the stub is a dummy and should be ignored. */ - if (flags & TPARG_FL_TPOINT) + if (ctx->flags & TPARG_FL_TPOINT) code->param++; #endif } else @@ -350,7 +376,7 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, return ret; inval_var: - trace_probe_log_err(offs, BAD_VAR); + trace_probe_log_err(ctx->offset, BAD_VAR); return -EINVAL; } @@ -383,7 +409,7 @@ static int __parse_imm_string(char *str, char **pbuf, int offs) static int parse_probe_arg(char *arg, const struct fetch_type *type, struct fetch_insn **pcode, struct fetch_insn *end, - unsigned int flags, int offs) + struct traceprobe_parse_context *ctx) { struct fetch_insn *code = *pcode; unsigned long param; @@ -394,13 +420,13 @@ parse_probe_arg(char *arg, const struct fetch_type *type, switch (arg[0]) { case '$': - ret = parse_probe_vars(arg + 1, type, code, flags, offs); + ret = parse_probe_vars(arg + 1, type, code, ctx); break; case '%': /* named register */ - if (flags & (TPARG_FL_TEVENT | TPARG_FL_FPROBE)) { + if (ctx->flags & (TPARG_FL_TEVENT | TPARG_FL_FPROBE)) { /* eprobe and fprobe do not handle registers */ - trace_probe_log_err(offs, BAD_VAR); + trace_probe_log_err(ctx->offset, BAD_VAR); break; } ret = regs_query_register_offset(arg + 1); @@ -409,14 +435,14 @@ parse_probe_arg(char *arg, const struct fetch_type *type, code->param = (unsigned int)ret; ret = 0; } else - trace_probe_log_err(offs, BAD_REG_NAME); + trace_probe_log_err(ctx->offset, BAD_REG_NAME); break; case '@': /* memory, file-offset or symbol */ if (isdigit(arg[1])) { ret = kstrtoul(arg + 1, 0, ¶m); if (ret) { - trace_probe_log_err(offs, BAD_MEM_ADDR); + trace_probe_log_err(ctx->offset, BAD_MEM_ADDR); break; } /* load address */ @@ -424,13 +450,13 @@ parse_probe_arg(char *arg, const struct fetch_type *type, code->immediate = param; } else if (arg[1] == '+') { /* kprobes don't support file offsets */ - if (flags & TPARG_FL_KERNEL) { - trace_probe_log_err(offs, FILE_ON_KPROBE); + if (ctx->flags & TPARG_FL_KERNEL) { + trace_probe_log_err(ctx->offset, FILE_ON_KPROBE); return -EINVAL; } ret = kstrtol(arg + 2, 0, &offset); if (ret) { - trace_probe_log_err(offs, BAD_FILE_OFFS); + trace_probe_log_err(ctx->offset, BAD_FILE_OFFS); break; } @@ -438,8 +464,8 @@ parse_probe_arg(char *arg, const struct fetch_type *type, code->immediate = (unsigned long)offset; // imm64? } else { /* uprobes don't support symbols */ - if (!(flags & TPARG_FL_KERNEL)) { - trace_probe_log_err(offs, SYM_ON_UPROBE); + if (!(ctx->flags & TPARG_FL_KERNEL)) { + trace_probe_log_err(ctx->offset, SYM_ON_UPROBE); return -EINVAL; } /* Preserve symbol for updating */ @@ -448,7 +474,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, if (!code->data) return -ENOMEM; if (++code == end) { - trace_probe_log_err(offs, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); return -EINVAL; } code->op = FETCH_OP_IMM; @@ -456,7 +482,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, } /* These are fetching from memory */ if (++code == end) { - trace_probe_log_err(offs, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); return -EINVAL; } *pcode = code; @@ -475,36 +501,38 @@ parse_probe_arg(char *arg, const struct fetch_type *type, arg++; /* Skip '+', because kstrtol() rejects it. */ tmp = strchr(arg, '('); if (!tmp) { - trace_probe_log_err(offs, DEREF_NEED_BRACE); + trace_probe_log_err(ctx->offset, DEREF_NEED_BRACE); return -EINVAL; } *tmp = '\0'; ret = kstrtol(arg, 0, &offset); if (ret) { - trace_probe_log_err(offs, BAD_DEREF_OFFS); + trace_probe_log_err(ctx->offset, BAD_DEREF_OFFS); break; } - offs += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0); + ctx->offset += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0); arg = tmp + 1; tmp = strrchr(arg, ')'); if (!tmp) { - trace_probe_log_err(offs + strlen(arg), + trace_probe_log_err(ctx->offset + strlen(arg), DEREF_OPEN_BRACE); return -EINVAL; } else { - const struct fetch_type *t2 = find_fetch_type(NULL, flags); + const struct fetch_type *t2 = find_fetch_type(NULL, ctx->flags); + int cur_offs = ctx->offset; *tmp = '\0'; - ret = parse_probe_arg(arg, t2, &code, end, flags, offs); + ret = parse_probe_arg(arg, t2, &code, end, ctx); if (ret) break; + ctx->offset = cur_offs; if (code->op == FETCH_OP_COMM || code->op == FETCH_OP_DATA) { - trace_probe_log_err(offs, COMM_CANT_DEREF); + trace_probe_log_err(ctx->offset, COMM_CANT_DEREF); return -EINVAL; } if (++code == end) { - trace_probe_log_err(offs, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); return -EINVAL; } *pcode = code; @@ -515,7 +543,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, break; case '\\': /* Immediate value */ if (arg[1] == '"') { /* Immediate string */ - ret = __parse_imm_string(arg + 2, &tmp, offs + 2); + ret = __parse_imm_string(arg + 2, &tmp, ctx->offset + 2); if (ret) break; code->op = FETCH_OP_DATA; @@ -523,7 +551,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, } else { ret = str_to_immediate(arg + 1, &code->immediate); if (ret) - trace_probe_log_err(offs + 1, BAD_IMM); + trace_probe_log_err(ctx->offset + 1, BAD_IMM); else code->op = FETCH_OP_IMM; } @@ -531,7 +559,7 @@ parse_probe_arg(char *arg, const struct fetch_type *type, } if (!ret && code->op == FETCH_OP_NOP) { /* Parsed, but do not find fetch method */ - trace_probe_log_err(offs, BAD_FETCH_ARG); + trace_probe_log_err(ctx->offset, BAD_FETCH_ARG); ret = -EINVAL; } return ret; @@ -576,12 +604,13 @@ static int __parse_bitfield_probe_arg(const char *bf, /* String length checking wrapper */ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, - struct probe_arg *parg, unsigned int flags, int offset) + struct probe_arg *parg, + struct traceprobe_parse_context *ctx) { struct fetch_insn *code, *scode, *tmp = NULL; char *t, *t2, *t3; - char *arg; int ret, len; + char *arg; arg = kstrdup(argv, GFP_KERNEL); if (!arg) @@ -590,10 +619,10 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, ret = -EINVAL; len = strlen(arg); if (len > MAX_ARGSTR_LEN) { - trace_probe_log_err(offset, ARG_TOO_LONG); + trace_probe_log_err(ctx->offset, ARG_TOO_LONG); goto out; } else if (len == 0) { - trace_probe_log_err(offset, NO_ARG_BODY); + trace_probe_log_err(ctx->offset, NO_ARG_BODY); goto out; } @@ -611,23 +640,24 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, *t2++ = '\0'; t3 = strchr(t2, ']'); if (!t3) { - offset += t2 + strlen(t2) - arg; - trace_probe_log_err(offset, + int offs = t2 + strlen(t2) - arg; + + trace_probe_log_err(ctx->offset + offs, ARRAY_NO_CLOSE); goto out; } else if (t3[1] != '\0') { - trace_probe_log_err(offset + t3 + 1 - arg, + trace_probe_log_err(ctx->offset + t3 + 1 - arg, BAD_ARRAY_SUFFIX); goto out; } *t3 = '\0'; if (kstrtouint(t2, 0, &parg->count) || !parg->count) { - trace_probe_log_err(offset + t2 - arg, + trace_probe_log_err(ctx->offset + t2 - arg, BAD_ARRAY_NUM); goto out; } if (parg->count > MAX_ARRAY_LEN) { - trace_probe_log_err(offset + t2 - arg, + trace_probe_log_err(ctx->offset + t2 - arg, ARRAY_TOO_BIG); goto out; } @@ -638,17 +668,17 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, * Since $comm and immediate string can not be dereferenced, * we can find those by strcmp. But ignore for eprobes. */ - if (!(flags & TPARG_FL_TEVENT) && + if (!(ctx->flags & TPARG_FL_TEVENT) && (strcmp(arg, "$comm") == 0 || 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"))) goto out; - parg->type = find_fetch_type("string", flags); + parg->type = find_fetch_type("string", ctx->flags); } else - parg->type = find_fetch_type(t, flags); + parg->type = find_fetch_type(t, ctx->flags); if (!parg->type) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), BAD_TYPE); + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_TYPE); goto out; } parg->offset = *size; @@ -670,7 +700,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, code[FETCH_INSN_MAX - 1].op = FETCH_OP_END; ret = parse_probe_arg(arg, parg->type, &code, &code[FETCH_INSN_MAX - 1], - flags, offset); + ctx); if (ret) goto fail; @@ -681,7 +711,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (code->op != FETCH_OP_REG && code->op != FETCH_OP_STACK && code->op != FETCH_OP_RETVAL && code->op != FETCH_OP_ARG && code->op != FETCH_OP_DEREF && code->op != FETCH_OP_TP_ARG) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_SYMSTRING); goto fail; } @@ -689,7 +719,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, 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_DATA && code->op != FETCH_OP_TP_ARG) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_STRING); goto fail; } @@ -708,7 +738,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, */ code++; if (code->op != FETCH_OP_NOP) { - trace_probe_log_err(offset, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); goto fail; } } @@ -731,7 +761,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, } else { code++; if (code->op != FETCH_OP_NOP) { - trace_probe_log_err(offset, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); goto fail; } code->op = FETCH_OP_ST_RAW; @@ -742,7 +772,7 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (t != NULL) { ret = __parse_bitfield_probe_arg(t, parg->type, &code); if (ret) { - trace_probe_log_err(offset + t - arg, BAD_BITFIELD); + trace_probe_log_err(ctx->offset + t - arg, BAD_BITFIELD); goto fail; } } @@ -752,13 +782,13 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (scode->op != FETCH_OP_ST_MEM && scode->op != FETCH_OP_ST_STRING && scode->op != FETCH_OP_ST_USTRING) { - trace_probe_log_err(offset + (t ? (t - arg) : 0), + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_STRING); goto fail; } code++; if (code->op != FETCH_OP_NOP) { - trace_probe_log_err(offset, TOO_MANY_OPS); + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); goto fail; } code->op = FETCH_OP_LP_ARRAY; @@ -807,7 +837,7 @@ static int traceprobe_conflict_field_name(const char *name, } int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg, - unsigned int flags) + struct traceprobe_parse_context *ctx) { struct probe_arg *parg = &tp->args[i]; const char *body; @@ -842,9 +872,9 @@ int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg, trace_probe_log_err(0, USED_ARG_NAME); return -EINVAL; } + ctx->offset = body - arg; /* Parse fetch argument */ - return traceprobe_parse_probe_arg_body(body, &tp->size, parg, flags, - body - arg); + return traceprobe_parse_probe_arg_body(body, &tp->size, parg, ctx); } void traceprobe_free_probe_arg(struct probe_arg *arg) diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 6b23206068f7..2dc1e5c4c9e8 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -374,8 +374,15 @@ static inline bool tparg_is_function_entry(unsigned int flags) return (flags & mask) == (TPARG_FL_KERNEL | TPARG_FL_FENTRY); } +struct traceprobe_parse_context { + struct trace_event_call *event; + unsigned int flags; + int offset; +}; + extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, - const char *argv, unsigned int flags); + const char *argv, + struct traceprobe_parse_context *ctx); extern int traceprobe_update_arg(struct probe_arg *arg); extern void traceprobe_free_probe_arg(struct probe_arg *arg); diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 8b92e34ff0c8..fa09b33ee731 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -686,10 +686,12 @@ static int __trace_uprobe_create(int argc, const char **argv) /* parse arguments */ for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct traceprobe_parse_context ctx = { + .flags = (is_return ? TPARG_FL_RETURN : 0) | TPARG_FL_USER, + }; + trace_probe_log_set_index(i + 2); - ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], - (is_return ? TPARG_FL_RETURN : 0) | - TPARG_FL_USER); + ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i], &ctx); if (ret) goto error; }