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

[Steven Rostedt]

On Wed, 18 Sep 2019 16:34:07 +0300
Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxxx>
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> Cc: Tzvetomir Stoyanov <tstoyanov@xxxxxxxxxx>
> Cc: linux-trace-devel@xxxxxxxxxxxxxxx
> Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
>  .../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@xxxxxxxxxxx>

-- 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;