Re: [PATCH v6 6/7] tracing/probe: Change traceprobe_set_print_fmt() to take a type

Masami Hiramatsu
2021-08-18T16:19:18Z

On Mon, 16 Aug 2021 23:43:01 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
>
> Instead of a boolean "is_return" have traceprobe_set_print_fmt() take a
> type (currently just PROBE_PRINT_NORMAL and PROBE_PRINT_RETURN). This will
> simplify adding different types. For example, the development of the
> event_probe, will need its own type as it prints an event, and not an IP.

This looks good and reasonable to me.

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>

Thank you!

>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
> ---
> kernel/trace/trace_kprobe.c | 9 +++++++--
> kernel/trace/trace_probe.c | 3 ++-
> kernel/trace/trace_probe.h | 7 ++++++-
> kernel/trace/trace_uprobe.c | 8 ++++++--
> 4 files changed, 21 insertions(+), 6 deletions(-)
>
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index ca726c9d0859..c6fe7a6e3f35 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -742,6 +742,7 @@ static int __trace_kprobe_create(int argc, const char *argv[])
> bool is_return = false;
> char *symbol = NULL, *tmp = NULL;
> const char *event = NULL, *group = KPROBE_EVENT_SYSTEM;
> + enum probe_print_type ptype;
> int maxactive = 0;
> long offset = 0;
> void *addr = NULL;
> @@ -875,7 +876,8 @@ static int __trace_kprobe_create(int argc, const char *argv[])
> goto error; /* This can be -ENOMEM */
> }
>
> - ret = traceprobe_set_print_fmt(&tk->tp, is_return);
> + ptype = is_return ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
> + ret = traceprobe_set_print_fmt(&tk->tp, ptype);
> if (ret < 0)
> goto error;
>
> @@ -1799,6 +1801,7 @@ struct trace_event_call *
> create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
> bool is_return)
> {
> + enum probe_print_type ptype;
> struct trace_kprobe *tk;
> int ret;
> char *event;
> @@ -1822,7 +1825,9 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
>
> init_trace_event_call(tk);
>
> - if (traceprobe_set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) {
> + ptype = trace_kprobe_is_return(tk) ?
> + PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
> + if (traceprobe_set_print_fmt(&tk->tp, ptype) < 0) {
> ret = -ENOMEM;
> goto error;
> }
> diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
> index 0916a9964719..a8dcadeaae95 100644
> --- a/kernel/trace/trace_probe.c
> +++ b/kernel/trace/trace_probe.c
> @@ -912,9 +912,10 @@ static int __set_print_fmt(struct trace_probe *tp, char *buf, int len,
> }
> #undef LEN_OR_ZERO
>
> -int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return)
> +int traceprobe_set_print_fmt(struct trace_probe *tp, enum probe_print_type ptype)
> {
> struct trace_event_call *call = trace_probe_event_call(tp);
> + bool is_return = ptype == PROBE_PRINT_RETURN;
> int len;
> char *print_fmt;
>
> diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
> index 42aa084902fa..8adf5f3542a6 100644
> --- a/kernel/trace/trace_probe.h
> +++ b/kernel/trace/trace_probe.h
> @@ -363,7 +363,12 @@ extern int traceprobe_split_symbol_offset(char *symbol, long *offset);
> int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
> char *buf, int offset);
>
> -extern int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return);
> +enum probe_print_type {
> + PROBE_PRINT_NORMAL,
> + PROBE_PRINT_RETURN,
> +};
> +
> +extern int traceprobe_set_print_fmt(struct trace_probe *tp, enum probe_print_type ptype);
>
> #ifdef CONFIG_PERF_EVENTS
> extern struct trace_event_call *
> diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
> index 590bb9a02f8d..09f8ca7f7ba0 100644
> --- a/kernel/trace/trace_uprobe.c
> +++ b/kernel/trace/trace_uprobe.c
> @@ -536,6 +536,7 @@ static int __trace_uprobe_create(int argc, const char **argv)
> const char *event = NULL, *group = UPROBE_EVENT_SYSTEM;
> char *arg, *filename, *rctr, *rctr_end, *tmp;
> char buf[MAX_EVENT_NAME_LEN];
> + enum probe_print_type ptype;
> struct path path;
> unsigned long offset, ref_ctr_offset;
> bool is_return = false;
> @@ -687,7 +688,8 @@ static int __trace_uprobe_create(int argc, const char **argv)
> goto error;
> }
>
> - ret = traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu));
> + ptype = is_ret_probe(tu) ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
> + ret = traceprobe_set_print_fmt(&tu->tp, ptype);
> if (ret < 0)
> goto error;
>
> @@ -1578,6 +1580,7 @@ struct trace_event_call *
> create_local_trace_uprobe(char *name, unsigned long offs,
> unsigned long ref_ctr_offset, bool is_return)
> {
> + enum probe_print_type ptype;
> struct trace_uprobe *tu;
> struct path path;
> int ret;
> @@ -1612,7 +1615,8 @@ create_local_trace_uprobe(char *name, unsigned long offs,
> tu->filename = kstrdup(name, GFP_KERNEL);
> init_trace_event_call(tu);
>
> - if (traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) {
> + ptype = is_ret_probe(tu) ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
> + if (traceprobe_set_print_fmt(&tu->tp, ptype) < 0) {
> ret = -ENOMEM;
> goto error;
> }
> --
> 2.30.2

--
Masami Hiramatsu <mhiramat@kernel.org>