From: Masami Hiramatsu <[email protected]> Decompose parse_probe_arg() by extracting register, memory/symbol, dereference, immediate, and default BTF/CPU parsing handlers into dedicated static helper functions (parse_probe_arg_register, parse_probe_arg_mem_symbol, parse_probe_arg_deref, parse_probe_arg_imm, and parse_probe_arg_default). This modularizes the recursive argument parser and improves readability.
Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <[email protected]> --- kernel/trace/trace_probe.c | 300 ++++++++++++++++++++++++++------------------ 1 file changed, 174 insertions(+), 126 deletions(-) diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 8af97e29f096..eb9f7bd13c19 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -1516,158 +1516,206 @@ static int __parse_imm_string(char *str, char **pbuf, int offs) return 0; } -/* Recursive argument parser */ -static int -parse_probe_arg(char *arg, const struct fetch_type *type, - struct fetch_insn **pcode, struct fetch_insn *end, - struct traceprobe_parse_context *ctx) +static int parse_probe_arg_register(char *arg, struct fetch_insn *code, + struct traceprobe_parse_context *ctx) +{ + int ret; + + if (ctx->flags & (TPARG_FL_TEVENT | TPARG_FL_FPROBE)) { + /* eprobe and fprobe do not handle registers */ + trace_probe_log_err(ctx->offset, BAD_VAR); + return -EINVAL; + } + ret = regs_query_register_offset(arg + 1); + if (ret >= 0) { + code->op = FETCH_OP_REG; + code->param = (unsigned int)ret; + return 0; + } + trace_probe_log_err(ctx->offset, BAD_REG_NAME); + return -EINVAL; +} + +static int parse_probe_arg_mem_symbol(char *arg, struct fetch_insn **pcode, + struct fetch_insn *end, + struct traceprobe_parse_context *ctx) { struct fetch_insn *code = *pcode; unsigned long param; + long offset = 0; + int ret; + + if (isdigit(arg[1])) { + ret = kstrtoul(arg + 1, 0, ¶m); + if (ret) { + trace_probe_log_err(ctx->offset, BAD_MEM_ADDR); + return ret; + } + /* load address */ + code->op = FETCH_OP_IMM; + code->immediate = param; + } else if (arg[1] == '+') { + /* Kernel probes do not support file offsets */ + 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(ctx->offset, BAD_FILE_OFFS); + return ret; + } + + code->op = FETCH_OP_FOFFS; + code->immediate = (unsigned long)offset; + offset = 0; + } else { + /* uprobes don't support symbols */ + if (!(ctx->flags & TPARG_FL_KERNEL)) { + trace_probe_log_err(ctx->offset, SYM_ON_UPROBE); + return -EINVAL; + } + /* Preserve symbol for updating */ + code->op = FETCH_NOP_SYMBOL; + code->data = kstrdup(arg + 1, GFP_KERNEL); + if (!code->data) + return -ENOMEM; + if (++code == end) { + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); + return -EINVAL; + } + code->op = FETCH_OP_IMM; + code->immediate = 0; + } + /* These are fetching from memory */ + if (++code == end) { + trace_probe_log_err(ctx->offset, TOO_MANY_OPS); + return -EINVAL; + } + *pcode = code; + code->op = FETCH_OP_DEREF; + code->offset = offset; + return 0; +} + +static int parse_probe_arg_deref(char *arg, struct fetch_insn **pcode, + struct fetch_insn *end, + struct traceprobe_parse_context *ctx) +{ int deref = FETCH_OP_DEREF; long offset = 0; char *tmp; - int ret = 0; + int ret; - switch (arg[0]) { - case '$': - ret = parse_probe_vars(arg, type, pcode, end, ctx); - break; + if (arg[1] == 'u') { + deref = FETCH_OP_UDEREF; + arg[1] = arg[0]; + arg++; + } + if (arg[0] == '+') + arg++; /* Skip '+', because kstrtol() rejects it. */ + tmp = strchr(arg, '('); + if (!tmp) { + trace_probe_log_err(ctx->offset, DEREF_NEED_BRACE); + return -EINVAL; + } + *tmp = '\0'; + ret = kstrtol(arg, 0, &offset); + if (ret) { + trace_probe_log_err(ctx->offset, BAD_DEREF_OFFS); + return ret; + } + ctx->offset += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0); + arg = tmp + 1; + return handle_dereference(arg, pcode, end, ctx, deref, offset); +} - case '%': /* named register */ - if (ctx->flags & (TPARG_FL_TEVENT | TPARG_FL_FPROBE)) { - /* eprobe and fprobe do not handle registers */ - trace_probe_log_err(ctx->offset, BAD_VAR); - break; +static int parse_probe_arg_imm(char *arg, struct fetch_insn *code, + struct traceprobe_parse_context *ctx) +{ + char *tmp; + int ret; + + if (arg[1] == '"') { /* Immediate string */ + ret = __parse_imm_string(arg + 2, &tmp, ctx->offset + 2); + if (ret) + return ret; + code->op = FETCH_OP_IMMSTR; + code->data = tmp; + } else { + ret = str_to_immediate(arg + 1, &code->immediate); + if (ret) { + trace_probe_log_err(ctx->offset + 1, BAD_IMM); + return ret; } - ret = regs_query_register_offset(arg + 1); - if (ret >= 0) { - code->op = FETCH_OP_REG; - code->param = (unsigned int)ret; - ret = 0; - } else - trace_probe_log_err(ctx->offset, BAD_REG_NAME); - break; + code->op = FETCH_OP_IMM; + } + return 0; +} - case '@': /* memory, file-offset or symbol */ - if (isdigit(arg[1])) { - ret = kstrtoul(arg + 1, 0, ¶m); - if (ret) { - trace_probe_log_err(ctx->offset, BAD_MEM_ADDR); - break; - } - /* load address */ - code->op = FETCH_OP_IMM; - code->immediate = param; - } else if (arg[1] == '+') { - /* Kernel probes do not support file offsets */ - 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(ctx->offset, BAD_FILE_OFFS); - break; - } +static int parse_probe_arg_default(char *arg, struct fetch_insn **pcode, + struct fetch_insn *end, + struct traceprobe_parse_context *ctx) +{ + int ret; - code->op = FETCH_OP_FOFFS; - code->immediate = (unsigned long)offset; // imm64? - offset = 0; - } else { - /* uprobes don't support symbols */ - if (!(ctx->flags & TPARG_FL_KERNEL)) { - trace_probe_log_err(ctx->offset, SYM_ON_UPROBE); - return -EINVAL; - } - /* Preserve symbol for updating */ - code->op = FETCH_NOP_SYMBOL; - code->data = kstrdup(arg + 1, GFP_KERNEL); - if (!code->data) - return -ENOMEM; - if (++code == end) { - trace_probe_log_err(ctx->offset, TOO_MANY_OPS); + if (str_has_prefix(arg, THIS_CPU_PTR_PREFIX) || + str_has_prefix(arg, THIS_CPU_READ_PREFIX)) { + return parse_this_cpu(arg, pcode, end, ctx); + } + + if (isalpha(arg[0]) || arg[0] == '_') { + /* BTF variable or event field */ + if (ctx->flags & TPARG_FL_TEVENT) { + ret = parse_trace_event(arg, *pcode, ctx); + if (ret < 0) { + trace_probe_log_err(ctx->offset, NO_EVENT_FIELD); return -EINVAL; } - code->op = FETCH_OP_IMM; - code->immediate = 0; + return 0; } - /* These are fetching from memory */ - if (++code == end) { - trace_probe_log_err(ctx->offset, TOO_MANY_OPS); + if (!tparg_is_function_entry(ctx->flags) && + !tparg_is_function_return(ctx->flags)) { + trace_probe_log_err(ctx->offset, NOSUP_BTFARG); return -EINVAL; } - *pcode = code; - code->op = FETCH_OP_DEREF; - code->offset = offset; - break; + return parse_btf_arg(arg, pcode, end, ctx); + } + return 0; +} + +/* Recursive argument parser */ +static int +parse_probe_arg(char *arg, const struct fetch_type *type, + struct fetch_insn **pcode, struct fetch_insn *end, + struct traceprobe_parse_context *ctx) +{ + struct fetch_insn *code = *pcode; + int ret; + + switch (arg[0]) { + case '$': + ret = parse_probe_vars(arg, type, pcode, end, ctx); + break; + case '%': /* named register */ + ret = parse_probe_arg_register(arg, code, ctx); + break; + case '@': /* memory, file-offset or symbol */ + ret = parse_probe_arg_mem_symbol(arg, pcode, end, ctx); + break; case '+': /* deref memory */ case '-': - if (arg[1] == 'u') { - deref = FETCH_OP_UDEREF; - arg[1] = arg[0]; - arg++; - } - if (arg[0] == '+') - arg++; /* Skip '+', because kstrtol() rejects it. */ - tmp = strchr(arg, '('); - if (!tmp) { - trace_probe_log_err(ctx->offset, DEREF_NEED_BRACE); - return -EINVAL; - } - *tmp = '\0'; - ret = kstrtol(arg, 0, &offset); - if (ret) { - trace_probe_log_err(ctx->offset, BAD_DEREF_OFFS); - break; - } - ctx->offset += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0); - arg = tmp + 1; - ret = handle_dereference(arg, pcode, end, ctx, deref, offset); - if (ret < 0) - return ret; + ret = parse_probe_arg_deref(arg, pcode, end, ctx); break; case '\\': /* Immediate value */ - if (arg[1] == '"') { /* Immediate string */ - ret = __parse_imm_string(arg + 2, &tmp, ctx->offset + 2); - if (ret) - break; - code->op = FETCH_OP_IMMSTR; - code->data = tmp; - } else { - ret = str_to_immediate(arg + 1, &code->immediate); - if (ret) - trace_probe_log_err(ctx->offset + 1, BAD_IMM); - else - code->op = FETCH_OP_IMM; - } + ret = parse_probe_arg_imm(arg, code, ctx); break; case '(': ret = handle_typecast(arg, pcode, end, ctx); break; default: - if (str_has_prefix(arg, THIS_CPU_PTR_PREFIX) || - str_has_prefix(arg, THIS_CPU_READ_PREFIX)) { - ret = parse_this_cpu(arg, pcode, end, ctx); - } else if (isalpha(arg[0]) || arg[0] == '_') { - /* BTF variable or event field*/ - if (ctx->flags & TPARG_FL_TEVENT) { - ret = parse_trace_event(arg, *pcode, ctx); - if (ret < 0) { - trace_probe_log_err(ctx->offset, - NO_EVENT_FIELD); - return -EINVAL; - } - break; - } - if (!tparg_is_function_entry(ctx->flags) && - !tparg_is_function_return(ctx->flags)) { - trace_probe_log_err(ctx->offset, NOSUP_BTFARG); - return -EINVAL; - } - ret = parse_btf_arg(arg, pcode, end, ctx); - } + ret = parse_probe_arg_default(arg, pcode, end, ctx); break; } if (!ret && code->op == FETCH_OP_NOP) {
