Re: [PATCH v7 01/13] tools lib traceevent: Convert remaining %p[fF] users to %p[sS]

Steven Rostedt
2019-09-18T13:59:02Z

On Wed, 18 Sep 2019 16:34:07 +0300
Sakari Ailus <sakari.ailus@linux.intel.com> wrote:

> There are no in-kernel %p[fF] users left. Convert the traceevent tool,
> too, to align with the kernel.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
> Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
> Cc: linux-trace-devel@vger.kernel.org
> Cc: Jiri Olsa <jolsa@redhat.com>
> Cc: Namhyung Kim <namhyung@kernel.org>
> ---
> .../Documentation/libtraceevent-func_apis.txt | 10 +++++-----
> tools/lib/traceevent/event-parse.c | 18 ++++++++++++++----
> 2 files changed, 19 insertions(+), 9 deletions(-)
>
> diff --git a/tools/lib/traceevent/Documentation/libtraceevent-func_apis.txt b/tools/lib/traceevent/Documentation/libtraceevent-func_apis.txt
> index 38bfea30a5f64..f6aca0df2151a 100644
> --- a/tools/lib/traceevent/Documentation/libtraceevent-func_apis.txt
> +++ b/tools/lib/traceevent/Documentation/libtraceevent-func_apis.txt
> @@ -59,12 +59,12 @@ parser context.
>
> The _tep_register_function()_ function registers a function name mapped to an
> address and (optional) module. This mapping is used in case the function tracer
> -or events have "%pF" or "%pS" parameter in its format string. It is common to
> -pass in the kallsyms function names with their corresponding addresses with this
> +or events have "%pS" parameter in its format string. It is common to pass in
> +the kallsyms function names with their corresponding addresses with this
> function. The _tep_ argument is the trace event parser context. The _name_ is
> -the name of the function, the string is copied internally. The _addr_ is
> -the start address of the function. The _mod_ is the kernel module
> -the function may be in (NULL for none).
> +the name of the function, the string is copied internally. The _addr_ is the
> +start address of the function. The _mod_ is the kernel module the function may
> +be in (NULL for none).
>
> The _tep_register_print_string()_ function registers a string by the address
> it was stored in the kernel. Some strings internal to the kernel with static
> diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
> index b36b536a9fcba..2189621b616bc 100644
> --- a/tools/lib/traceevent/event-parse.c
> +++ b/tools/lib/traceevent/event-parse.c
> @@ -4335,10 +4335,20 @@ static struct tep_print_arg *make_bprint_args(char *fmt, void *data, int size, s
> switch (*ptr) {
> case 's':
> case 'S':
> - case 'f':
> - case 'F':
> case 'x':
> break;
> + case 'f':
> + case 'F':
> + /*
> + * Pre-5.5 kernels use %pf and
> + * %pF for printing symbols
> + * while kernels since 5.5 use
> + * %pfw for fwnodes. So check
> + * %p[fF] isn't followed by 'w'.
> + */

Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

-- Steve

> + if (ptr[1] != 'w')
> + break;
> + /* fall through */
> default:
> /*
> * Older kernels do not process
> @@ -4455,12 +4465,12 @@ get_bprint_format(void *data, int size __maybe_unused,
>
> printk = find_printk(tep, addr);
> if (!printk) {
> - if (asprintf(&format, "%%pf: (NO FORMAT FOUND at %llx)\n", addr) < 0)
> + if (asprintf(&format, "%%ps: (NO FORMAT FOUND at %llx)\n", addr) < 0)
> return NULL;
> return format;
> }
>
> - if (asprintf(&format, "%s: %s", "%pf", printk->printk) < 0)
> + if (asprintf(&format, "%s: %s", "%ps", printk->printk) < 0)
> return NULL;
>
> return format;