diff options
| author | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2023-08-23 01:26:32 +0900 |
|---|---|---|
| committer | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2023-08-23 09:41:13 +0900 |
| commit | 27973e5c64b9e6dbea06a3ee86ed7509147b3848 (patch) | |
| tree | aadf61b9eb2eb851a160b3587fdb5daf4770e042 /kernel/trace/trace_probe.h | |
| parent | d157d7694460b9aa5b974c37b1ad5fb10c8f8b7c (diff) | |
tracing/probes: Add string type check with BTF
Add a string type checking with BTF information if possible.
This will check whether the given BTF argument (and field) is
signed char array or pointer to signed char. If not, it reject
the 'string' type. If it is pointer to signed char, it adds
a dereference opration so that it can correctly fetch the
string data from memory.
# echo 'f getname_flags%return retval->name:string' >> dynamic_events
# echo 't sched_switch next->comm:string' >> dynamic_events
The above cases, 'struct filename::name' is 'char *' and
'struct task_struct::comm' is 'char []'. But in both case,
user can specify ':string' to fetch the string data.
Link: https://lore.kernel.org/all/169272159250.160970.1881112937198526188.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_probe.h')
| -rw-r--r-- | kernel/trace/trace_probe.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 9184c84833f8..7f929482e8d4 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -513,7 +513,8 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(NOSUP_DAT_ARG, "Non pointer structure/union argument is not supported."),\ C(BAD_HYPHEN, "Failed to parse single hyphen. Forgot '>'?"), \ C(NO_BTF_FIELD, "This field is not found."), \ - C(BAD_BTF_TID, "Failed to get BTF type info."), + C(BAD_BTF_TID, "Failed to get BTF type info."),\ + C(BAD_TYPE4STR, "This type does not fit for string."), #undef C #define C(a, b) TP_ERR_##a |