perf tests: Add a test case for checking sw clock event frequency

This test case checks frequency conversion of hrtimer-based software
clock events (cpu-clock, task-clock) have valid (non-1) periods.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1363574507-18808-2-git-send-email-namhyung@kernel.org
[ committer note: Moved .sample_freq to outside named init block to cope with some gcc versions ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

4 files changed, 125 insertions, 0 deletions

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 8e1bba35a1ee..0230b75ed7f9 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -514,6 +514,7 @@ LIB_OBJS += $(OUTPUT)tests/python-use.o
 LIB_OBJS += $(OUTPUT)tests/bp_signal.o
 LIB_OBJS += $(OUTPUT)tests/bp_signal_overflow.o
 LIB_OBJS += $(OUTPUT)tests/task-exit.o
+LIB_OBJS += $(OUTPUT)tests/sw-clock.o
 
 BUILTIN_OBJS += $(OUTPUT)builtin-annotate.o
 BUILTIN_OBJS += $(OUTPUT)builtin-bench.o
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 9b5c70a180d2..0918ada4cc41 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -90,6 +90,10 @@ static struct test {
                 .func = test__task_exit,
         },
         {
+                .desc = "Test software clock events have valid period values",
+                .func = test__sw_clock_freq,
+        },
+        {
                 .func = NULL,
         },
 };
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;
+}
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index b33b3286ad6e..dd7feae2d37b 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -26,5 +26,6 @@ int test__python_use(void);
 int test__bp_signal(void);
 int test__bp_signal_overflow(void);
 int test__task_exit(void);
+int test__sw_clock_freq(void);
 
 #endif /* TESTS_H */