From: Omar Sandoval <[email protected]> You'd only ever want $comm as a string, but the default is still u64. Push the type parsing later so we can decide based on the actual fetcharg and make "string" the default for $comm.
Signed-off-by: Omar Sandoval <[email protected]> --- Documentation/trace/kprobetrace.txt | 6 +-- Documentation/trace/uprobetracer.txt | 6 +-- kernel/trace/trace_probe.c | 102 +++++++++++++++++++++++------------ 3 files changed, 75 insertions(+), 39 deletions(-) diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt index 0bf746656d06..da3b437d4e5e 100644 --- a/Documentation/trace/kprobetrace.txt +++ b/Documentation/trace/kprobetrace.txt @@ -40,7 +40,7 @@ Synopsis of kprobe_events $stackN : Fetch Nth entry of stack (N >= 0) $stack : Fetch stack address. $retval : Fetch return value.(*) - $comm : Fetch current task comm.(***) + $comm : Fetch current task comm. +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**) NAME=FETCHARG : Set NAME as the argument name of FETCHARG. FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types @@ -49,7 +49,6 @@ Synopsis of kprobe_events (*) only for return probe. (**) this is useful for fetching a field of data structures. - (***) you probably want this as a string, i.e., $comm:string Types ----- @@ -65,7 +64,8 @@ offset, and container-size (usually 32). The syntax is; b<bit-width>@<bit-offset>/<container-size> -For $comm, the type must be either "string" or "string_size". +For $comm, the type must be either "string" or "string_size". The default is +"string". Per-Probe Event Filtering diff --git a/Documentation/trace/uprobetracer.txt b/Documentation/trace/uprobetracer.txt index 34754da46860..5daa61cf431a 100644 --- a/Documentation/trace/uprobetracer.txt +++ b/Documentation/trace/uprobetracer.txt @@ -36,7 +36,7 @@ Synopsis of uprobe_tracer $stackN : Fetch Nth entry of stack (N >= 0) $stack : Fetch stack address. $retval : Fetch return value.(*) - $comm : Fetch current task comm.(***) + $comm : Fetch current task comm. +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**) NAME=FETCHARG : Set NAME as the argument name of FETCHARG. FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types @@ -45,7 +45,6 @@ Synopsis of uprobe_tracer (*) only for return probe. (**) this is useful for fetching a field of data structures. - (***) you probably want this as a string, i.e., $comm:string Types ----- @@ -60,7 +59,8 @@ offset, and container-size (usually 32). The syntax is; b<bit-width>@<bit-offset>/<container-size> -For $comm, the type must be either "string" or "string_size". +For $comm, the type must be either "string" or "string_size". The default is +"string". Event Profiling diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 3900b6e4a05d..6b0a553308f9 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -296,6 +296,26 @@ static void fetch_user_stack_address(struct pt_regs *regs, void *dummy, void *de } NOKPROBE_SYMBOL(fetch_user_stack_address); +static int parse_fetch_type(const char *t, ssize_t *size, + const struct fetch_type **tp, + const struct fetch_type *ftbl, + const char *default_t) +{ + if (!t) + t = default_t; + + *tp = find_fetch_type(t, ftbl); + if (!*tp) { + pr_info("Unsupported type: %s\n", t); + return -EINVAL; + } + + if (size) + *size += (*tp)->size; + + return 0; +} + static fetch_func_t get_fetch_size_function(const struct fetch_type *type, fetch_func_t orig_fn, const struct fetch_type *ftbl) @@ -339,21 +359,28 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset) #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) -static int parse_probe_vars(char *arg, const struct fetch_type *t, - struct fetch_param *f, bool is_return, - bool is_kprobe) +static int parse_probe_vars(char *arg, const char *t, ssize_t *size, + const struct fetch_type **tp, struct fetch_param *f, + bool is_return, bool is_kprobe, + const struct fetch_type *ftbl) { int ret = 0; unsigned long param; if (strcmp(arg, "retval") == 0) { + ret = parse_fetch_type(t, size, tp, ftbl, NULL); + if (ret) + return ret; if (is_return) - f->fn = t->fetch[FETCH_MTD_retval]; + f->fn = (*tp)->fetch[FETCH_MTD_retval]; else ret = -EINVAL; } else if (strncmp(arg, "stack", 5) == 0) { + ret = parse_fetch_type(t, size, tp, ftbl, NULL); + if (ret) + return ret; if (arg[5] == '\0') { - if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR)) + if (strcmp((*tp)->name, DEFAULT_FETCH_TYPE_STR)) return -EINVAL; if (is_kprobe) @@ -365,16 +392,19 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, if (ret || (is_kprobe && param > PARAM_MAX_STACK)) ret = -EINVAL; else { - f->fn = t->fetch[FETCH_MTD_stack]; + f->fn = (*tp)->fetch[FETCH_MTD_stack]; f->data = (void *)param; } } else ret = -EINVAL; } else if (strcmp(arg, "comm") == 0) { - if (strcmp(t->name, "string") != 0 && - strcmp(t->name, "string_size") != 0) + ret = parse_fetch_type(t, size, tp, ftbl, "string"); + if (ret) + return ret; + if (strcmp((*tp)->name, "string") != 0 && + strcmp((*tp)->name, "string_size") != 0) return -EINVAL; - f->fn = t->fetch[FETCH_MTD_comm]; + f->fn = (*tp)->fetch[FETCH_MTD_comm]; } else ret = -EINVAL; @@ -382,9 +412,10 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, } /* Recursive argument parser */ -static int parse_probe_arg(char *arg, const struct fetch_type *t, - struct fetch_param *f, bool is_return, bool is_kprobe, - const struct fetch_type *ftbl) +static int parse_probe_arg(char *arg, const char *t, ssize_t *size, + const struct fetch_type **tp, + struct fetch_param *f, bool is_return, + bool is_kprobe, const struct fetch_type *ftbl) { unsigned long param; long offset; @@ -393,25 +424,32 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, switch (arg[0]) { case '$': - ret = parse_probe_vars(arg + 1, t, f, is_return, is_kprobe); + ret = parse_probe_vars(arg + 1, t, size, tp, f, is_return, + is_kprobe, ftbl); break; case '%': /* named register */ + ret = parse_fetch_type(t, size, tp, ftbl, NULL); + if (ret) + break; ret = regs_query_register_offset(arg + 1); if (ret >= 0) { - f->fn = t->fetch[FETCH_MTD_reg]; + f->fn = (*tp)->fetch[FETCH_MTD_reg]; f->data = (void *)(unsigned long)ret; ret = 0; } break; case '@': /* memory, file-offset or symbol */ + ret = parse_fetch_type(t, size, tp, ftbl, NULL); + if (ret) + break; if (isdigit(arg[1])) { ret = kstrtoul(arg + 1, 0, ¶m); if (ret) break; - f->fn = t->fetch[FETCH_MTD_memory]; + f->fn = (*tp)->fetch[FETCH_MTD_memory]; f->data = (void *)param; } else if (arg[1] == '+') { /* kprobes don't support file offsets */ @@ -422,7 +460,7 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, if (ret) break; - f->fn = t->fetch[FETCH_MTD_file_offset]; + f->fn = (*tp)->fetch[FETCH_MTD_file_offset]; f->data = (void *)offset; } else { /* uprobes don't support symbols */ @@ -435,13 +473,16 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, f->data = alloc_symbol_cache(arg + 1, offset); if (f->data) - f->fn = t->fetch[FETCH_MTD_symbol]; + f->fn = (*tp)->fetch[FETCH_MTD_symbol]; } break; case '+': /* deref memory */ arg++; /* Skip '+', because kstrtol() rejects it. */ case '-': + ret = parse_fetch_type(t, size, tp, ftbl, NULL); + if (ret) + break; tmp = strchr(arg, '('); if (!tmp) break; @@ -459,7 +500,6 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, struct deref_fetch_param *dprm; const struct fetch_type *t2; - t2 = find_fetch_type(NULL, ftbl); *tmp = '\0'; dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL); @@ -467,22 +507,24 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, return -ENOMEM; dprm->offset = offset; - dprm->fetch = t->fetch[FETCH_MTD_memory]; - dprm->fetch_size = get_fetch_size_function(t, - dprm->fetch, ftbl); - ret = parse_probe_arg(arg, t2, &dprm->orig, is_return, - is_kprobe, ftbl); + dprm->fetch = (*tp)->fetch[FETCH_MTD_memory]; + dprm->fetch_size = get_fetch_size_function((*tp), + dprm->fetch, + ftbl); + ret = parse_probe_arg(arg, NULL, NULL, &t2, &dprm->orig, + is_return, is_kprobe, ftbl); if (ret) kfree(dprm); else { - f->fn = t->fetch[FETCH_MTD_deref]; + f->fn = (*tp)->fetch[FETCH_MTD_deref]; f->data = (void *)dprm; } } break; } if (!ret && !f->fn) { /* Parsed, but do not find fetch method */ - pr_info("%s type has no corresponding fetch method.\n", t->name); + pr_info("%s type has no corresponding fetch method.\n", + (*tp)->name); ret = -EINVAL; } @@ -549,15 +591,9 @@ int traceprobe_parse_probe_arg(char *arg, ssize_t *size, arg[t - parg->comm] = '\0'; t++; } - parg->type = find_fetch_type(t, ftbl); - if (!parg->type) { - pr_info("Unsupported type: %s\n", t); - return -EINVAL; - } parg->offset = *size; - *size += parg->type->size; - ret = parse_probe_arg(arg, parg->type, &parg->fetch, is_return, - is_kprobe, ftbl); + ret = parse_probe_arg(arg, t, size, &parg->type, &parg->fetch, + is_return, is_kprobe, ftbl); if (ret >= 0 && t != NULL) ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch); -- 2.8.3
