[PATCH v2] libperf tests: Fix test_stat_cpu

From: Shunsuke Nakamura
Date: Wed Oct 06 2021 - 05:48:26 EST


`cpu` of perf_evsel__read() must be specified the cpu index.
perf_cpu_map__for_each_cpu is for iterating the cpu number (not index)
and is not appropriate.
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.

Committer testing:

# 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>
---
Previous version at:
https://lore.kernel.org/lkml/20211006080456.474273-1-nakamura.shun@xxxxxxxxxxx/

Changes in v2:
- Remove "2/2" from Patch Subject

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 c67c83399170..47badd7eabf2 100644
--- a/tools/lib/perf/tests/test-evlist.c
+++ b/tools/lib/perf/tests/test-evlist.c
@@ -40,7 +40,7 @@ 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);
@@ -70,10 +70,10 @@ 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 9abd4c0bf6db..33ae9334861a 100644
--- a/tools/lib/perf/tests/test-evsel.c
+++ b/tools/lib/perf/tests/test-evsel.c
@@ -22,7 +22,7 @@ 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);
@@ -33,10 +33,10 @@ 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);
}

--
2.25.1