tools/lib/perf/tests/test-evlist.c

Source file repositories/reference/linux-study-clean/tools/lib/perf/tests/test-evlist.c

File Facts

System
Linux kernel
Corpus path
tools/lib/perf/tests/test-evlist.c
Extension
.c
Size
13817 bytes
Lines
590
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

while ((event = perf_mmap__read_event(map)) != NULL) {
			count++;
			perf_mmap__consume(map);
		}

		perf_mmap__read_done(map);
	}

	/* calls perf_evlist__munmap/perf_evlist__close */
	perf_evlist__delete(evlist);

	perf_thread_map__put(threads);
	perf_cpu_map__put(cpus);

	/*
	 * The generated prctl calls should match the
	 * number of events in the buffer.
	 */
	__T("failed count", count == 100);

	return 0;
}

static int test_mmap_cpus(void)
{
	struct perf_evlist *evlist;
	struct perf_evsel *evsel;
	struct perf_mmap *map;
	struct perf_cpu_map *cpus;
	struct perf_event_attr attr = {
		.type             = PERF_TYPE_TRACEPOINT,
		.sample_period    = 1,
		.wakeup_watermark = 1,
		.disabled         = 1,
	};
	cpu_set_t saved_mask;
	char path[PATH_MAX];
	int id, err, tmp;
	struct perf_cpu cpu;
	union perf_event *event;
	int count = 0;

	snprintf(path, PATH_MAX, "%s/kernel/debug/tracing/events/syscalls/sys_enter_prctl/id",
		 sysfs__mountpoint());

	if (filename__read_int(path, &id)) {
		fprintf(stderr, "error: failed to get tracepoint id: %s\n", path);
		return -1;
	}

	attr.config = id;

	cpus = perf_cpu_map__new_online_cpus();
	__T("failed to create cpus", cpus);

	evlist = perf_evlist__new();
	__T("failed to create evlist", evlist);

	evsel = perf_evsel__new(&attr);
	__T("failed to create evsel1", evsel);
	__T("failed to set leader", evsel->leader == evsel);

	perf_evlist__add(evlist, evsel);

	perf_evlist__set_maps(evlist, cpus, NULL);

	err = perf_evlist__open(evlist);
	__T("failed to open evlist", err == 0);

	err = perf_evlist__mmap(evlist, 4);
	__T("failed to mmap evlist", err == 0);

	perf_evlist__enable(evlist);

	err = sched_getaffinity(0, sizeof(saved_mask), &saved_mask);
	__T("sched_getaffinity failed", err == 0);

	perf_cpu_map__for_each_cpu(cpu, tmp, cpus) {
		cpu_set_t mask;

		CPU_ZERO(&mask);
		CPU_SET(cpu.cpu, &mask);

		err = sched_setaffinity(0, sizeof(mask), &mask);
		__T("sched_setaffinity failed", err == 0);

		prctl(0, 0, 0, 0, 0);
	}

	err = sched_setaffinity(0, sizeof(saved_mask), &saved_mask);

Annotation

Implementation Notes