// SPDX-License-Identifier: GPL-2.0 #include <linux/types.h> #include <limits.h> #include <unistd.h> #include <sys/prctl.h> #include <perf/cpumap.h> #include <perf/evlist.h> #include <perf/mmap.h> #include "debug.h" #include "parse-events.h" #include "evlist.h" #include "evsel.h" #include "record.h" #include "thread_map.h" #include "tests.h" #include "util/mmap.h" #define CHECK__(x) { \ while ((x) < 0) { \ pr_debug(#x " failed!\n"); \ goto out_err; \ } \ } #define CHECK_NOT_NULL__(x) { \ while ((x) == NULL) { \ pr_debug(#x " failed!\n"); \ goto out_err; \ } \ } static int find_comm(struct evlist *evlist, const char *comm) { union perf_event *event; struct mmap *md; int i, found; found = 0; for (i = 0; i < evlist->core.nr_mmaps; i++) { md = &evlist->mmap[i]; if (perf_mmap__read_init(&md->core) < 0) continue; while ((event = perf_mmap__read_event(&md->core)) != NULL) { if (event->header.type == PERF_RECORD_COMM && (pid_t)event->comm.pid == getpid() && (pid_t)event->comm.tid == getpid() && strcmp(event->comm.comm, comm) == 0) found += 1; perf_mmap__consume(&md->core); } perf_mmap__read_done(&md->core); } return found; } /** * test__keep_tracking - test using a dummy software event to keep tracking. * * This function implements a test that checks that tracking events continue * when an event is disabled but a dummy software event is not disabled. If the * test passes %0 is returned, otherwise %-1 is returned. */ static int test__keep_tracking(struct test_suite *test __maybe_unused, int subtest __maybe_unused) { struct record_opts opts = { .mmap_pages = UINT_MAX, .user_freq = UINT_MAX, .user_interval = ULLONG_MAX, .target = { .uses_mmap = true, }, }; struct perf_thread_map *threads = NULL; struct perf_cpu_map *cpus = NULL; struct evlist *evlist = NULL; struct evsel *evsel = NULL; int found, err = -1; const char *comm; threads = thread_map__new(-1, getpid(), UINT_MAX); CHECK_NOT_NULL__(threads); cpus = perf_cpu_map__new(NULL); CHECK_NOT_NULL__(cpus); evlist = evlist__new(); CHECK_NOT_NULL__(evlist); perf_evlist__set_maps(&evlist->core, cpus, threads); CHECK__(parse_event(evlist, "dummy:u")); CHECK__(parse_event(evlist, "cycles:u")); evlist__config(evlist, &opts, NULL); evsel = evlist__first(evlist); evsel->core.attr.comm = 1; evsel->core.attr.disabled = 1; evsel->core.attr.enable_on_exec = 0; if (evlist__open(evlist) < 0) { pr_debug("Unable to open dummy and cycles event\n"); err = TEST_SKIP; goto out_err; } CHECK__(evlist__mmap(evlist, UINT_MAX)); /* * First, test that a 'comm' event can be found when the event is * enabled. */ evlist__enable(evlist); comm = "Test COMM 1"; CHECK__(prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0)); evlist__disable(evlist); found = find_comm(evlist, comm); if (found != 1) { pr_debug("First time, failed to find tracking event.\n"); goto out_err; } /* * Secondly, test that a 'comm' event can be found when the event is * disabled with the dummy event still enabled. */ evlist__enable(evlist); evsel = evlist__last(evlist); CHECK__(evsel__disable(evsel)); comm = "Test COMM 2"; CHECK__(prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0)); evlist__disable(evlist); found = find_comm(evlist, comm); if (found != 1) { pr_debug("Second time, failed to find tracking event.\n"); goto out_err; } err = 0; out_err: if (evlist) { evlist__disable(evlist); evlist__delete(evlist); } perf_cpu_map__put(cpus); perf_thread_map__put(threads); return err; } DEFINE_SUITE("Use a dummy software event to keep tracking", keep_tracking);