Em Mon, May 09, 2022 at 03:42:52PM +0100, James Clark escreveu:
> Architectures can detect availability of extra registers at
> runtime so use this more complete set for unwinding. This
> will include the VG register on arm64 in a later commit.
>
> If the function isn't implemented then PERF_REGS_MASK is
> returned and there is no change.
Committer notes:
Added util/perf_regs.c to tools/perf/util/python-ext-sources so that
'perf test python' passes, i.e. the perf python binding has all the
symbols it needs, addressing:
$ perf test -v python
19: 'import perf' in python :
--- start ---
test child forked, pid 2037817
python usage test: "echo "import sys ; sys.path.append('/tmp/build/perf/python'); import perf" | '/usr/bin/python3' "
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: /tmp/build/perf/python/perf.cpython-310-x86_64-linux-gnu.so: undefined symbol: arch__user_reg_mask
test child finished with -1
---- end ----
'import perf' in python: FAILED!
$
> Signed-off-by: James Clark <james.clark@xxxxxxx>
> ---
> tools/perf/util/evsel.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index d38722560e80..a881784da966 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -875,7 +875,7 @@ static void __evsel__config_callchain(struct evsel *evsel, struct record_opts *o
> "specifying a subset with --user-regs may render DWARF unwinding unreliable, "
> "so the minimal registers set (IP, SP) is explicitly forced.\n");
> } else {
> - attr->sample_regs_user |= PERF_REGS_MASK;
> + attr->sample_regs_user |= arch__user_reg_mask();
> }
> attr->sample_stack_user = param->dump_size;
> attr->exclude_callchain_user = 1;
> --
> 2.28.0
--
- Arnaldo
