[PATCH] libperf: Fix perf_cpu_map__for_each_cpu macro

From: Jiri Olsa
Date: Tue Feb 15 2022 - 10:43:08 EST


Tzvetomir Stoyanov reported an issue with using macro
perf_cpu_map__for_each_cpu using private perf_cpu object.

The issue is caused by recent change that wrapped cpu in struct
perf_cpu to distinguish it from cpu indexes. We need to make
struct perf_cpu public.

Adding simple test for using perf_cpu_map__for_each_cpu
macro.

Fixes: 6d18804b963b ("perf cpumap: Give CPUs their own type")
Reported-by: Tzvetomir Stoyanov <tz.stoyanov@xxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/lib/perf/include/internal/cpumap.h | 6 +-----
tools/lib/perf/include/perf/cpumap.h | 5 +++++
tools/lib/perf/libperf.map | 1 +
tools/lib/perf/tests/test-cpumap.c | 11 +++++++++++
4 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/tools/lib/perf/include/internal/cpumap.h b/tools/lib/perf/include/internal/cpumap.h
index 581f9ffb4237..1973a18c096b 100644
--- a/tools/lib/perf/include/internal/cpumap.h
+++ b/tools/lib/perf/include/internal/cpumap.h
@@ -3,11 +3,7 @@
#define __LIBPERF_INTERNAL_CPUMAP_H

#include <linux/refcount.h>
-
-/** A wrapper around a CPU to avoid confusion with the perf_cpu_map's map's indices. */
-struct perf_cpu {
- int cpu;
-};
+#include <perf/cpumap.h>

/**
* A sized, reference counted, sorted array of integers representing CPU
diff --git a/tools/lib/perf/include/perf/cpumap.h b/tools/lib/perf/include/perf/cpumap.h
index 15b8faafd615..4a2edbdb5e2b 100644
--- a/tools/lib/perf/include/perf/cpumap.h
+++ b/tools/lib/perf/include/perf/cpumap.h
@@ -7,6 +7,11 @@
#include <stdio.h>
#include <stdbool.h>

+/** A wrapper around a CPU to avoid confusion with the perf_cpu_map's map's indices. */
+struct perf_cpu {
+ int cpu;
+};
+
LIBPERF_API struct perf_cpu_map *perf_cpu_map__dummy_new(void);
LIBPERF_API struct perf_cpu_map *perf_cpu_map__default_new(void);
LIBPERF_API struct perf_cpu_map *perf_cpu_map__new(const char *cpu_list);
diff --git a/tools/lib/perf/libperf.map b/tools/lib/perf/libperf.map
index 93696affda2e..6fa0d651576b 100644
--- a/tools/lib/perf/libperf.map
+++ b/tools/lib/perf/libperf.map
@@ -2,6 +2,7 @@ LIBPERF_0.0.1 {
global:
libperf_init;
perf_cpu_map__dummy_new;
+ perf_cpu_map__default_new;
perf_cpu_map__get;
perf_cpu_map__put;
perf_cpu_map__new;
diff --git a/tools/lib/perf/tests/test-cpumap.c b/tools/lib/perf/tests/test-cpumap.c
index d39378eaf897..87b0510a556f 100644
--- a/tools/lib/perf/tests/test-cpumap.c
+++ b/tools/lib/perf/tests/test-cpumap.c
@@ -14,6 +14,8 @@ static int libperf_print(enum libperf_print_level level,
int test_cpumap(int argc, char **argv)
{
struct perf_cpu_map *cpus;
+ struct perf_cpu cpu;
+ int idx;

__T_START;

@@ -27,6 +29,15 @@ int test_cpumap(int argc, char **argv)
perf_cpu_map__put(cpus);
perf_cpu_map__put(cpus);

+ cpus = perf_cpu_map__default_new();
+ if (!cpus)
+ return -1;
+
+ perf_cpu_map__for_each_cpu(cpu, idx, cpus)
+ __T("wrong cpu number", cpu.cpu != -1);
+
+ perf_cpu_map__put(cpus);
+
__T_END;
return tests_failed == 0 ? 0 : -1;
}
--
2.35.1