diff options
Diffstat (limited to 'tools/perf/tests/mmap-basic.c')
| -rw-r--r-- | tools/perf/tests/mmap-basic.c | 162 | 
1 files changed, 162 insertions, 0 deletions
diff --git a/tools/perf/tests/mmap-basic.c b/tools/perf/tests/mmap-basic.c new file mode 100644 index 00000000000..e1746811e14 --- /dev/null +++ b/tools/perf/tests/mmap-basic.c @@ -0,0 +1,162 @@ +#include "evlist.h" +#include "evsel.h" +#include "thread_map.h" +#include "cpumap.h" +#include "tests.h" + +/* + * This test will generate random numbers of calls to some getpid syscalls, + * then establish an mmap for a group of events that are created to monitor + * the syscalls. + * + * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated + * sample.id field to map back to its respective perf_evsel instance. + * + * Then it checks if the number of syscalls reported as perf events by + * the kernel corresponds to the number of syscalls made. + */ +int test__basic_mmap(void) +{ +	int err = -1; +	union perf_event *event; +	struct thread_map *threads; +	struct cpu_map *cpus; +	struct perf_evlist *evlist; +	struct perf_event_attr attr = { +		.type		= PERF_TYPE_TRACEPOINT, +		.read_format	= PERF_FORMAT_ID, +		.sample_type	= PERF_SAMPLE_ID, +		.watermark	= 0, +	}; +	cpu_set_t cpu_set; +	const char *syscall_names[] = { "getsid", "getppid", "getpgrp", +					"getpgid", }; +	pid_t (*syscalls[])(void) = { (void *)getsid, getppid, getpgrp, +				      (void*)getpgid }; +#define nsyscalls ARRAY_SIZE(syscall_names) +	int ids[nsyscalls]; +	unsigned int nr_events[nsyscalls], +		     expected_nr_events[nsyscalls], i, j; +	struct perf_evsel *evsels[nsyscalls], *evsel; + +	for (i = 0; i < nsyscalls; ++i) { +		char name[64]; + +		snprintf(name, sizeof(name), "sys_enter_%s", syscall_names[i]); +		ids[i] = trace_event__id(name); +		if (ids[i] < 0) { +			pr_debug("Is debugfs mounted on /sys/kernel/debug?\n"); +			return -1; +		} +		nr_events[i] = 0; +		expected_nr_events[i] = random() % 257; +	} + +	threads = thread_map__new(-1, getpid(), UINT_MAX); +	if (threads == NULL) { +		pr_debug("thread_map__new\n"); +		return -1; +	} + +	cpus = cpu_map__new(NULL); +	if (cpus == NULL) { +		pr_debug("cpu_map__new\n"); +		goto out_free_threads; +	} + +	CPU_ZERO(&cpu_set); +	CPU_SET(cpus->map[0], &cpu_set); +	sched_setaffinity(0, sizeof(cpu_set), &cpu_set); +	if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) { +		pr_debug("sched_setaffinity() failed on CPU %d: %s ", +			 cpus->map[0], strerror(errno)); +		goto out_free_cpus; +	} + +	evlist = perf_evlist__new(cpus, threads); +	if (evlist == NULL) { +		pr_debug("perf_evlist__new\n"); +		goto out_free_cpus; +	} + +	/* anonymous union fields, can't be initialized above */ +	attr.wakeup_events = 1; +	attr.sample_period = 1; + +	for (i = 0; i < nsyscalls; ++i) { +		attr.config = ids[i]; +		evsels[i] = perf_evsel__new(&attr, i); +		if (evsels[i] == NULL) { +			pr_debug("perf_evsel__new\n"); +			goto out_free_evlist; +		} + +		perf_evlist__add(evlist, evsels[i]); + +		if (perf_evsel__open(evsels[i], cpus, threads) < 0) { +			pr_debug("failed to open counter: %s, " +				 "tweak /proc/sys/kernel/perf_event_paranoid?\n", +				 strerror(errno)); +			goto out_close_fd; +		} +	} + +	if (perf_evlist__mmap(evlist, 128, true) < 0) { +		pr_debug("failed to mmap events: %d (%s)\n", errno, +			 strerror(errno)); +		goto out_close_fd; +	} + +	for (i = 0; i < nsyscalls; ++i) +		for (j = 0; j < expected_nr_events[i]; ++j) { +			int foo = syscalls[i](); +			++foo; +		} + +	while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) { +		struct perf_sample sample; + +		if (event->header.type != PERF_RECORD_SAMPLE) { +			pr_debug("unexpected %s event\n", +				 perf_event__name(event->header.type)); +			goto out_munmap; +		} + +		err = perf_evlist__parse_sample(evlist, event, &sample); +		if (err) { +			pr_err("Can't parse sample, err = %d\n", err); +			goto out_munmap; +		} + +		evsel = perf_evlist__id2evsel(evlist, sample.id); +		if (evsel == NULL) { +			pr_debug("event with id %" PRIu64 +				 " doesn't map to an evsel\n", sample.id); +			goto out_munmap; +		} +		nr_events[evsel->idx]++; +	} + +	list_for_each_entry(evsel, &evlist->entries, node) { +		if (nr_events[evsel->idx] != expected_nr_events[evsel->idx]) { +			pr_debug("expected %d %s events, got %d\n", +				 expected_nr_events[evsel->idx], +				 perf_evsel__name(evsel), nr_events[evsel->idx]); +			goto out_munmap; +		} +	} + +	err = 0; +out_munmap: +	perf_evlist__munmap(evlist); +out_close_fd: +	for (i = 0; i < nsyscalls; ++i) +		perf_evsel__close_fd(evsels[i], 1, threads->nr); +out_free_evlist: +	perf_evlist__delete(evlist); +out_free_cpus: +	cpu_map__delete(cpus); +out_free_threads: +	thread_map__delete(threads); +	return err; +}  |