Hi Tom,
On Wed, 13 Feb 2019 12:17:55 -0600
Tom Zanussi <zanussi@xxxxxxxxxx> wrote:
> From: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
>
> Here are a few examples of replacing kprobe_events error handling with
> tracing_log_err() from the new tracing error_log mechanism. Only a
> few example errors are converted, and even these are incomplete, since
> I didn't know where to get the current command and used a dummy string
> for those. Also, these are completely untested, just provided for
> RFC purposes.
OK, can I take this over? I would like to try to use this framework.
>
> With this change, users will find some kprobe_events errors in
> tracing/error_log instead of dmesg.
Yes, that is much better, especially for ftracetest.
Thank you,
>
> TODO: If acceptable, convert all the rest of the kprobe errors and
> figure out how to get the actual cmd logged along with the error.
>
> Signed-off-by: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
> ---
> kernel/trace/trace_probe.c | 24 ++++++++++++++++++++----
> 1 file changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
> index 9962cb5da8ac..3d7b195c943b 100644
> --- a/kernel/trace/trace_probe.c
> +++ b/kernel/trace/trace_probe.c
> @@ -13,6 +13,22 @@
>
> #include "trace_probe.h"
>
> +#define ERRORS \
> + C(NONE, "No error"), \
> + C(INVALID_STRING_SPEC, "string only accepts memory or address."), \
> + C(ARG_TOO_LONG, "Argument is too long."), \
> + C(INVALID_ARG_NAME, "Invalid argument name"),
> +
> +#undef C
> +#define C(a, b) KPROBE_ERR_##a
> +
> +enum { ERRORS };
> +
> +#undef C
> +#define C(a, b) b
> +
> +static const char *err_text[] = { ERRORS };
> +
> const char *reserved_field_names[] = {
> "common_type",
> "common_flags",
> @@ -384,7 +400,7 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
> int ret, len;
>
> if (strlen(arg) > MAX_ARGSTR_LEN) {
> - pr_info("Argument is too long.: %s\n", arg);
> + tracing_log_err("kprobe_events", "replace this with command", err_text, KPROBE_ERR_ARG_TOO_LONG, err_pos("command", arg));
> return -ENOSPC;
> }
> parg->comm = kstrdup(arg, GFP_KERNEL);
> @@ -443,7 +459,8 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
> if (!strcmp(parg->type->name, "string")) {
> if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_IMM &&
> code->op != FETCH_OP_COMM) {
> - pr_info("string only accepts memory or address.\n");
> + tracing_log_err("kprobe_events", "replace this with command", err_text, KPROBE_ERR_INVALID_STRING_SPEC, 0);
> +
> ret = -EINVAL;
> goto fail;
> }
> @@ -558,8 +575,7 @@ int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, char *arg,
> return -ENOMEM;
>
> if (!is_good_name(parg->name)) {
> - pr_info("Invalid argument[%d] name: %s\n",
> - i, parg->name);
> + tracing_log_err("kprobe_events", "replace this with command", err_text, KPROBE_ERR_INVALID_ARG_NAME, err_pos("cmd", parg->name));
> return -EINVAL;
> }
>
> --
> 2.14.1
>
--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>
