diff options
Diffstat (limited to 'tools/perf/tests/sw-clock.c')
-rw-r--r-- | tools/perf/tests/sw-clock.c | 119 |
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 00000000000..2e41e2d32cc --- /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; +} |