[PATCH 5.10 78/95] libperf tests: Fix test_stat_cpu

From: Greg Kroah-Hartman
Date: Mon Oct 25 2021 - 15:42:43 EST


From: Shunsuke Nakamura <nakamura.shun@xxxxxxxxxxx>

[ Upstream commit 3ff6d64e68abc231955d216236615918797614ae ]

The `cpu` argument of perf_evsel__read() must specify the cpu index.

perf_cpu_map__for_each_cpu() is for iterating the cpu number (not index)
and is thus not appropriate for use with perf_evsel__read().

So, if there is an offline CPU, the cpu number specified in the argument
may point out of range because the cpu number and the cpu index are
different.

Fix test_stat_cpu().

Testing it:

# make tests -C tools/lib/perf/
make: Entering directory '/home/nakamura/kernel_src/linux-5.15-rc4_fix/tools/lib/perf'
running static:
- running tests/test-cpumap.c...OK
- running tests/test-threadmap.c...OK
- running tests/test-evlist.c...OK
- running tests/test-evsel.c...OK
running dynamic:
- running tests/test-cpumap.c...OK
- running tests/test-threadmap.c...OK
- running tests/test-evlist.c...OK
- running tests/test-evsel.c...OK
make: Leaving directory '/home/nakamura/kernel_src/linux-5.15-rc4_fix/tools/lib/perf'

Signed-off-by: Shunsuke Nakamura <nakamura.shun@xxxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lore.kernel.org/lkml/20211011083704.4108720-1-nakamura.shun@xxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/lib/perf/tests/test-evlist.c | 6 +++---
tools/lib/perf/tests/test-evsel.c | 6 +++---
2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/tools/lib/perf/tests/test-evlist.c b/tools/lib/perf/tests/test-evlist.c
index bd19cabddaf6..60b5d1801103 100644
--- a/tools/lib/perf/tests/test-evlist.c
+++ b/tools/lib/perf/tests/test-evlist.c
@@ -38,7 +38,7 @@ static int test_stat_cpu(void)
.type = PERF_TYPE_SOFTWARE,
.config = PERF_COUNT_SW_TASK_CLOCK,
};
- int err, cpu, tmp;
+ int err, idx;

cpus = perf_cpu_map__new(NULL);
__T("failed to create cpus", cpus);
@@ -64,10 +64,10 @@ static int test_stat_cpu(void)
perf_evlist__for_each_evsel(evlist, evsel) {
cpus = perf_evsel__cpus(evsel);

- perf_cpu_map__for_each_cpu(cpu, tmp, cpus) {
+ for (idx = 0; idx < perf_cpu_map__nr(cpus); idx++) {
struct perf_counts_values counts = { .val = 0 };

- perf_evsel__read(evsel, cpu, 0, &counts);
+ perf_evsel__read(evsel, idx, 0, &counts);
__T("failed to read value for evsel", counts.val != 0);
}
}
diff --git a/tools/lib/perf/tests/test-evsel.c b/tools/lib/perf/tests/test-evsel.c
index 0ad82d7a2a51..2de98768d844 100644
--- a/tools/lib/perf/tests/test-evsel.c
+++ b/tools/lib/perf/tests/test-evsel.c
@@ -21,7 +21,7 @@ static int test_stat_cpu(void)
.type = PERF_TYPE_SOFTWARE,
.config = PERF_COUNT_SW_CPU_CLOCK,
};
- int err, cpu, tmp;
+ int err, idx;

cpus = perf_cpu_map__new(NULL);
__T("failed to create cpus", cpus);
@@ -32,10 +32,10 @@ static int test_stat_cpu(void)
err = perf_evsel__open(evsel, cpus, NULL);
__T("failed to open evsel", err == 0);

- perf_cpu_map__for_each_cpu(cpu, tmp, cpus) {
+ for (idx = 0; idx < perf_cpu_map__nr(cpus); idx++) {
struct perf_counts_values counts = { .val = 0 };

- perf_evsel__read(evsel, cpu, 0, &counts);
+ perf_evsel__read(evsel, idx, 0, &counts);
__T("failed to read value for evsel", counts.val != 0);
}

--
2.33.0