[PATCH v2 1/4] perf expr: Add debug logging for literals

From: Ian Rogers
Date: Tue Nov 23 2021 - 19:12:38 EST


Useful for diagnosing problems with metrics.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/expr.c | 35 ++++++++++++++++++++++++-----------
1 file changed, 24 insertions(+), 11 deletions(-)

diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c
index 1d532b9fed29..cdbab4f959fe 100644
--- a/tools/perf/util/expr.c
+++ b/tools/perf/util/expr.c
@@ -395,12 +395,17 @@ double expr_id_data__source_count(const struct expr_id_data *data)
double expr__get_literal(const char *literal)
{
static struct cpu_topology *topology;
+ double result = NAN;

- if (!strcmp("#smt_on", literal))
- return smt_on() > 0 ? 1.0 : 0.0;
+ if (!strcmp("#smt_on", literal)) {
+ result = smt_on() > 0 ? 1.0 : 0.0;
+ goto out;
+ }

- if (!strcmp("#num_cpus", literal))
- return cpu__max_present_cpu();
+ if (!strcmp("#num_cpus", literal)) {
+ result = cpu__max_present_cpu();
+ goto out;
+ }

/*
* Assume that topology strings are consistent, such as CPUs "0-1"
@@ -415,13 +420,21 @@ double expr__get_literal(const char *literal)
return NAN;
}
}
- if (!strcmp("#num_packages", literal))
- return topology->package_cpus_lists;
- if (!strcmp("#num_dies", literal))
- return topology->die_cpus_lists;
- if (!strcmp("#num_cores", literal))
- return topology->core_cpus_lists;
+ if (!strcmp("#num_packages", literal)) {
+ result = topology->package_cpus_lists;
+ goto out;
+ }
+ if (!strcmp("#num_dies", literal)) {
+ result = topology->die_cpus_lists;
+ goto out;
+ }
+ if (!strcmp("#num_cores", literal)) {
+ result = topology->core_cpus_lists;
+ goto out;
+ }

pr_err("Unrecognized literal '%s'", literal);
- return NAN;
+out:
+ pr_debug2("literal: %s = %f\n", literal, result);
+ return result;
}
--
2.34.0.rc2.393.gf8c9666880-goog