1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/types.h>
  3#include <unistd.h>
  4#include <sys/prctl.h>
  5
  6#include "parse-events.h"
  7#include "evlist.h"
  8#include "evsel.h"
  9#include "thread_map.h"
 10#include "cpumap.h"
 11#include "tests.h"
 12
 13#define CHECK__(x) {				\
 14	while ((x) < 0) {			\
 15		pr_debug(#x " failed!\n");	\
 16		goto out_err;			\
 17	}					\
 18}
 19
 20#define CHECK_NOT_NULL__(x) {			\
 21	while ((x) == NULL) {			\
 22		pr_debug(#x " failed!\n");	\
 23		goto out_err;			\
 24	}					\
 25}
 26
 27static int find_comm(struct perf_evlist *evlist, const char *comm)
 28{
 29	union perf_event *event;
 30	struct perf_mmap *md;
 31	int i, found;
 32
 33	found = 0;
 34	for (i = 0; i < evlist->nr_mmaps; i++) {
 35		md = &evlist->mmap[i];
 36		if (perf_mmap__read_init(md) < 0)
 37			continue;
 38		while ((event = perf_mmap__read_event(md)) != NULL) {
 39			if (event->header.type == PERF_RECORD_COMM &&
 40			    (pid_t)event->comm.pid == getpid() &&
 41			    (pid_t)event->comm.tid == getpid() &&
 42			    strcmp(event->comm.comm, comm) == 0)
 43				found += 1;
 44			perf_mmap__consume(md);
 45		}
 46		perf_mmap__read_done(md);
 47	}
 48	return found;
 49}
 50
 51/**
 52 * test__keep_tracking - test using a dummy software event to keep tracking.
 53 *
 54 * This function implements a test that checks that tracking events continue
 55 * when an event is disabled but a dummy software event is not disabled.  If the
 56 * test passes %0 is returned, otherwise %-1 is returned.
 57 */
 58int test__keep_tracking(struct test *test __maybe_unused, int subtest __maybe_unused)
 59{
 60	struct record_opts opts = {
 61		.mmap_pages	     = UINT_MAX,
 62		.user_freq	     = UINT_MAX,
 63		.user_interval	     = ULLONG_MAX,
 64		.target		     = {
 65			.uses_mmap   = true,
 66		},
 67	};
 68	struct thread_map *threads = NULL;
 69	struct cpu_map *cpus = NULL;
 70	struct perf_evlist *evlist = NULL;
 71	struct perf_evsel *evsel = NULL;
 72	int found, err = -1;
 73	const char *comm;
 74
 75	threads = thread_map__new(-1, getpid(), UINT_MAX);
 76	CHECK_NOT_NULL__(threads);
 77
 78	cpus = cpu_map__new(NULL);
 79	CHECK_NOT_NULL__(cpus);
 80
 81	evlist = perf_evlist__new();
 82	CHECK_NOT_NULL__(evlist);
 83
 84	perf_evlist__set_maps(evlist, cpus, threads);
 85
 86	CHECK__(parse_events(evlist, "dummy:u", NULL));
 87	CHECK__(parse_events(evlist, "cycles:u", NULL));
 88
 89	perf_evlist__config(evlist, &opts, NULL);
 90
 91	evsel = perf_evlist__first(evlist);
 92
 93	evsel->attr.comm = 1;
 94	evsel->attr.disabled = 1;
 95	evsel->attr.enable_on_exec = 0;
 96
 97	if (perf_evlist__open(evlist) < 0) {
 98		pr_debug("Unable to open dummy and cycles event\n");
 99		err = TEST_SKIP;
100		goto out_err;
101	}
102
103	CHECK__(perf_evlist__mmap(evlist, UINT_MAX));
104
105	/*
106	 * First, test that a 'comm' event can be found when the event is
107	 * enabled.
108	 */
109
110	perf_evlist__enable(evlist);
111
112	comm = "Test COMM 1";
113	CHECK__(prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0));
114
115	perf_evlist__disable(evlist);
116
117	found = find_comm(evlist, comm);
118	if (found != 1) {
119		pr_debug("First time, failed to find tracking event.\n");
120		goto out_err;
121	}
122
123	/*
124	 * Secondly, test that a 'comm' event can be found when the event is
125	 * disabled with the dummy event still enabled.
126	 */
127
128	perf_evlist__enable(evlist);
129
130	evsel = perf_evlist__last(evlist);
131
132	CHECK__(perf_evsel__disable(evsel));
133
134	comm = "Test COMM 2";
135	CHECK__(prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0));
136
137	perf_evlist__disable(evlist);
138
139	found = find_comm(evlist, comm);
140	if (found != 1) {
141		pr_debug("Seconf time, failed to find tracking event.\n");
142		goto out_err;
143	}
144
145	err = 0;
146
147out_err:
148	if (evlist) {
149		perf_evlist__disable(evlist);
150		perf_evlist__delete(evlist);
151	} else {
152		cpu_map__put(cpus);
153		thread_map__put(threads);
154	}
155
156	return err;
157}