perf tests: Add a test case for checking sw clock event frequency
Namhyung Kim [Mon, 18 Mar 2013 02:41:47 +0000 (11:41 +0900)]
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>

tools/perf/Makefile
tools/perf/tests/builtin-test.c
tools/perf/tests/sw-clock.c [new file with mode: 0644]
tools/perf/tests/tests.h

index 8e1bba3..0230b75 100644 (file)
@@ -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
index 9b5c70a..0918ada 100644 (file)
@@ -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 (file)
index 0000000..2e41e2d
--- /dev/null
@@ -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;
+}
index b33b328..dd7feae 100644 (file)
@@ -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 */