Re: [PATCH v2] perf scripting python: expose symbol offset and source information

[Eelco Chaudron]

On 22 Feb 2022, at 16:11, Eelco Chaudron wrote:

> This change adds the symbol offset to the data exported for each
> call-chain entry. This can not be calculated from the script and
> only the ip value, and no related mmap information.
>
> In addition, also export the source file and line information, if
> available, to avoid an external lookup if this information is needed.
>
> Signed-off-by: Eelco Chaudron <echaudro@xxxxxxxxxx>

Hi All, was wondering if this patch got lost?

> ---
> v2:
>  - Fixed small code nit
>  - Included new features in auto generated scripts
>
>  .../util/scripting-engines/trace-event-python.c    |   49 +++++++++++++++-----
>  1 file changed, 36 insertions(+), 13 deletions(-)
>
> diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
> index e752e1f4a5f0..86a9c8614231 100644
> --- a/tools/perf/util/scripting-engines/trace-event-python.c
> +++ b/tools/perf/util/scripting-engines/trace-event-python.c
> @@ -392,6 +392,18 @@ static const char *get_dsoname(struct map *map)
>  	return dsoname;
>  }
>
> +static unsigned long get_offset(struct symbol *sym, struct addr_location *al)
> +{
> +	unsigned long offset;
> +
> +	if (al->addr < sym->end)
> +		offset = al->addr - sym->start;
> +	else
> +		offset = al->addr - al->map->start - sym->start;
> +
> +	return offset;
> +}
> +
>  static PyObject *python_process_callchain(struct perf_sample *sample,
>  					 struct evsel *evsel,
>  					 struct addr_location *al)
> @@ -443,6 +455,25 @@ static PyObject *python_process_callchain(struct perf_sample *sample,
>  					_PyUnicode_FromStringAndSize(node->ms.sym->name,
>  							node->ms.sym->namelen));
>  			pydict_set_item_string_decref(pyelem, "sym", pysym);
> +
> +			if (node->ms.map) {
> +				struct map *map = node->ms.map;
> +				struct addr_location node_al;
> +				unsigned long offset;
> +
> +				node_al.addr = map->map_ip(map, node->ip);
> +				node_al.map  = map;
> +				offset = get_offset(node->ms.sym, &node_al);
> +
> +				pydict_set_item_string_decref(
> +					pyelem, "sym_off",
> +					PyLong_FromUnsignedLongLong(offset));
> +			}
> +			if (node->srcline && strcmp(":0", node->srcline)) {
> +				pydict_set_item_string_decref(
> +					pyelem, "sym_srcline",
> +					_PyUnicode_FromString(node->srcline));
> +			}
>  		}
>
>  		if (node->ms.map) {
> @@ -520,18 +551,6 @@ static PyObject *python_process_brstack(struct perf_sample *sample,
>  	return pylist;
>  }
>
> -static unsigned long get_offset(struct symbol *sym, struct addr_location *al)
> -{
> -	unsigned long offset;
> -
> -	if (al->addr < sym->end)
> -		offset = al->addr - sym->start;
> -	else
> -		offset = al->addr - al->map->start - sym->start;
> -
> -	return offset;
> -}
> -
>  static int get_symoff(struct symbol *sym, struct addr_location *al,
>  		      bool print_off, char *bf, int size)
>  {
> @@ -2073,7 +2092,11 @@ static int python_generate_script(struct tep_handle *pevent, const char *outfile
>
>  		fprintf(ofp, "\t\tfor node in common_callchain:");
>  		fprintf(ofp, "\n\t\t\tif 'sym' in node:");
> -		fprintf(ofp, "\n\t\t\t\tprint(\"\\t[%%x] %%s\" %% (node['ip'], node['sym']['name']))");
> +		fprintf(ofp, "\n\t\t\t\tprint(\"\t[%%x] %%s%%s%%s%%s\" %% (");
> +		fprintf(ofp, "\n\t\t\t\t\tnode['ip'], node['sym']['name'],");
> +		fprintf(ofp, "\n\t\t\t\t\t\"+0x{:x}\".format(node['sym_off']) if 'sym_off' in node else \"\",");
> +		fprintf(ofp, "\n\t\t\t\t\t\" ({})\".format(node['dso'])  if 'dso' in node else \"\",");
> +		fprintf(ofp, "\n\t\t\t\t\t\" \" + node['sym_srcline'] if 'sym_srcline' in node else \"\"))");
>  		fprintf(ofp, "\n\t\t\telse:");
>  		fprintf(ofp, "\n\t\t\t\tprint(\"\t[%%x]\" %% (node['ip']))\n\n");
>  		fprintf(ofp, "\t\tprint()\n\n");