1 files changed, 119 insertions, 0 deletions

diff --git a/tools/perf/tests/sw-clock.c b/tools/perf/tests/sw-clock.c
new file mode 100644
index 000000000000..2e41e2d32ccc
--- /dev/null
+++ b/tools/perf/tests/sw-clock.c
@@ -0,0 +1,119 @@
+#include <unistd.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <sys/mman.h>
+
+#include "tests.h"
+#include "util/evsel.h"
+#include "util/evlist.h"
+#include "util/cpumap.h"
+#include "util/thread_map.h"
+
+#define NR_LOOPS  1000000
+
+/*
+ * This test will open software clock events (cpu-clock, task-clock)
+ * then check their frequency -> period conversion has no artifact of
+ * setting period to 1 forcefully.
+ */
+static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
+{
+        int i, err = -1;
+        volatile int tmp = 0;
+        u64 total_periods = 0;
+        int nr_samples = 0;
+        union perf_event *event;
+        struct perf_evsel *evsel;
+        struct perf_evlist *evlist;
+        struct perf_event_attr attr = {
+                .type = PERF_TYPE_SOFTWARE,
+                .config = clock_id,
+                .sample_type = PERF_SAMPLE_PERIOD,
+                .exclude_kernel = 1,
+                .disabled = 1,
+                .freq = 1,
+        };
+
+        attr.sample_freq = 10000;
+
+        evlist = perf_evlist__new();
+        if (evlist == NULL) {
+                pr_debug("perf_evlist__new\n");
+                return -1;
+        }
+
+        evsel = perf_evsel__new(&attr, 0);
+        if (evsel == NULL) {
+                pr_debug("perf_evsel__new\n");
+                goto out_free_evlist;
+        }
+        perf_evlist__add(evlist, evsel);
+
+        evlist->cpus = cpu_map__dummy_new();
+        evlist->threads = thread_map__new_by_tid(getpid());
+        if (!evlist->cpus || !evlist->threads) {
+                err = -ENOMEM;
+                pr_debug("Not enough memory to create thread/cpu maps\n");
+                goto out_delete_maps;
+        }
+
+        perf_evlist__open(evlist);
+
+        err = perf_evlist__mmap(evlist, 128, true);
+        if (err < 0) {
+                pr_debug("failed to mmap event: %d (%s)\n", errno,
+                         strerror(errno));
+                goto out_close_evlist;
+        }
+
+        perf_evlist__enable(evlist);
+
+        /* collect samples */
+        for (i = 0; i < NR_LOOPS; i++)
+                tmp++;
+
+        perf_evlist__disable(evlist);
+
+        while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
+                struct perf_sample sample;
+
+                if (event->header.type != PERF_RECORD_SAMPLE)
+                        continue;
+
+                err = perf_evlist__parse_sample(evlist, event, &sample);
+                if (err < 0) {
+                        pr_debug("Error during parse sample\n");
+                        goto out_unmap_evlist;
+                }
+
+                total_periods += sample.period;
+                nr_samples++;
+        }
+
+        if ((u64) nr_samples == total_periods) {
+                pr_debug("All (%d) samples have period value of 1!\n",
+                         nr_samples);
+                err = -1;
+        }
+
+out_unmap_evlist:
+        perf_evlist__munmap(evlist);
+out_close_evlist:
+        perf_evlist__close(evlist);
+out_delete_maps:
+        perf_evlist__delete_maps(evlist);
+out_free_evlist:
+        perf_evlist__delete(evlist);
+        return err;
+}
+
+int test__sw_clock_freq(void)
+{
+        int ret;
+
+        ret = __test__sw_clock_freq(PERF_COUNT_SW_CPU_CLOCK);
+        if (!ret)
+                ret = __test__sw_clock_freq(PERF_COUNT_SW_TASK_CLOCK);
+
+        return ret;
+}