On 2/23/21 8:49 PM, Arnaldo Carvalho de Melo wrote:

Em Mon, Feb 22, 2021 at 09:29:22AM +0100, Martin Liška escreveu:

quoted

Perf annotate supports --symbol but it's impossible to filter
a C++ symbol. With --no-demangle one can filter easily by
mangled function name.

Signed-off-by: Martin Liška <redacted>
---
  tools/perf/Documentation/perf-annotate.txt | 7 +++++++
  tools/perf/builtin-annotate.c              | 4 ++++
  2 files changed, 11 insertions(+)

diff --git a/tools/perf/Documentation/perf-annotate.txt b/tools/perf/Documentation/perf-annotate.txt
index 1b5042f134a8..80c1be5d566c 100644
--- a/tools/perf/Documentation/perf-annotate.txt
+++ b/tools/perf/Documentation/perf-annotate.txt

@@ -124,6 +124,13 @@ OPTIONS
  --group::
  	Show event group information together
+--demangle::
+	Demangle symbol names to human readable form. It's enabled by default,
+	disable with --no-demangle.
+
+--demangle-kernel::
+	Demangle kernel symbol names to human readable form (for C++ kernels).
+
  --percent-type::
  	Set annotation percent type from following choices:
  	  global-period, local-period, global-hits, local-hits

diff --git a/tools/perf/builtin-annotate.c b/tools/perf/builtin-annotate.c
index a23ba6bb99b6..ef70a17b9b5b 100644
--- a/tools/perf/builtin-annotate.c
+++ b/tools/perf/builtin-annotate.c

@@ -538,6 +538,10 @@ int cmd_annotate(int argc, const char **argv)
  		    "Strip first N entries of source file path name in programs (with --prefix)"),
  	OPT_STRING(0, "objdump", &annotate.opts.objdump_path, "path",
  		   "objdump binary to use for disassembly and annotations"),
+	OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
+		    "Disable symbol demangling"),

Nope, this _enables_ demangling, i.e.:

	perf annotate --demangle

Oh, yeah, you are right.

Asks for symbol demangling, while:

	perf annotate --no-demangle

As you correctly wrote in your commit message and on the
--demangle-kernel case, enables demangling.

Fixed that in V2.

Martin

Please consider making this configurable (if not already) via
~/.perfconfig, 'perf config', sure in a followup patch.

Thanks,

- Arnaldo

quoted

+	OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
+		    "Enable kernel symbol demangling"),
  	OPT_BOOLEAN(0, "group", &symbol_conf.event_group,
  		    "Show event group information together"),
  	OPT_BOOLEAN(0, "show-total-period", &symbol_conf.show_total_period,
-- 
2.30.1