1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <inttypes.h>
4 #include <limits.h>
5 #include <stdbool.h>
6 #include <stdio.h>
7 #include <unistd.h>
8 #include <linux/types.h>
9 #include <sys/prctl.h>
10 #include <perf/cpumap.h>
11 #include <perf/evlist.h>
12 #include <perf/mmap.h>
13 
14 #include "debug.h"
15 #include "parse-events.h"
16 #include "evlist.h"
17 #include "evsel.h"
18 #include "thread_map.h"
19 #include "record.h"
20 #include "tsc.h"
21 #include "mmap.h"
22 #include "tests.h"
23 
24 /*
25  * Except x86_64/i386 and Arm64, other archs don't support TSC in perf.  Just
26  * enable the test for x86_64/i386 and Arm64 archs.
27  */
28 #if defined(__x86_64__) || defined(__i386__) || defined(__aarch64__)
29 #define TSC_IS_SUPPORTED 1
30 #else
31 #define TSC_IS_SUPPORTED 0
32 #endif
33 
34 #define CHECK__(x) {				\
35 	while ((x) < 0) {			\
36 		pr_debug(#x " failed!\n");	\
37 		goto out_err;			\
38 	}					\
39 }
40 
41 #define CHECK_NOT_NULL__(x) {			\
42 	while ((x) == NULL) {			\
43 		pr_debug(#x " failed!\n");	\
44 		goto out_err;			\
45 	}					\
46 }
47 
48 static int test__tsc_is_supported(struct test_suite *test __maybe_unused,
49 				  int subtest __maybe_unused)
50 {
51 	if (!TSC_IS_SUPPORTED) {
52 		pr_debug("Test not supported on this architecture\n");
53 		return TEST_SKIP;
54 	}
55 
56 	return TEST_OK;
57 }
58 
59 /**
60  * test__perf_time_to_tsc - test converting perf time to TSC.
61  *
62  * This function implements a test that checks that the conversion of perf time
63  * to and from TSC is consistent with the order of events.  If the test passes
64  * %0 is returned, otherwise %-1 is returned.  If TSC conversion is not
65  * supported then then the test passes but " (not supported)" is printed.
66  */
67 static int test__perf_time_to_tsc(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
68 {
69 	struct record_opts opts = {
70 		.mmap_pages	     = UINT_MAX,
71 		.user_freq	     = UINT_MAX,
72 		.user_interval	     = ULLONG_MAX,
73 		.target		     = {
74 			.uses_mmap   = true,
75 		},
76 		.sample_time	     = true,
77 	};
78 	struct perf_thread_map *threads = NULL;
79 	struct perf_cpu_map *cpus = NULL;
80 	struct evlist *evlist = NULL;
81 	struct evsel *evsel = NULL;
82 	int err = TEST_FAIL, ret, i;
83 	const char *comm1, *comm2;
84 	struct perf_tsc_conversion tc;
85 	struct perf_event_mmap_page *pc;
86 	union perf_event *event;
87 	u64 test_tsc, comm1_tsc, comm2_tsc;
88 	u64 test_time, comm1_time = 0, comm2_time = 0;
89 	struct mmap *md;
90 
91 
92 	threads = thread_map__new(-1, getpid(), UINT_MAX);
93 	CHECK_NOT_NULL__(threads);
94 
95 	cpus = perf_cpu_map__new(NULL);
96 	CHECK_NOT_NULL__(cpus);
97 
98 	evlist = evlist__new();
99 	CHECK_NOT_NULL__(evlist);
100 
101 	perf_evlist__set_maps(&evlist->core, cpus, threads);
102 
103 	CHECK__(parse_events(evlist, "cycles:u", NULL));
104 
105 	evlist__config(evlist, &opts, NULL);
106 
107 	/* For hybrid "cycles:u", it creates two events */
108 	evlist__for_each_entry(evlist, evsel) {
109 		evsel->core.attr.comm = 1;
110 		evsel->core.attr.disabled = 1;
111 		evsel->core.attr.enable_on_exec = 0;
112 	}
113 
114 	ret = evlist__open(evlist);
115 	if (ret < 0) {
116 		if (ret == -ENOENT)
117 			err = TEST_SKIP;
118 		else
119 			pr_debug("evlist__open() failed\n");
120 		goto out_err;
121 	}
122 
123 	CHECK__(evlist__mmap(evlist, UINT_MAX));
124 
125 	pc = evlist->mmap[0].core.base;
126 	ret = perf_read_tsc_conversion(pc, &tc);
127 	if (ret) {
128 		if (ret == -EOPNOTSUPP) {
129 			pr_debug("perf_read_tsc_conversion is not supported in current kernel\n");
130 			err = TEST_SKIP;
131 		}
132 		goto out_err;
133 	}
134 
135 	evlist__enable(evlist);
136 
137 	comm1 = "Test COMM 1";
138 	CHECK__(prctl(PR_SET_NAME, (unsigned long)comm1, 0, 0, 0));
139 
140 	test_tsc = rdtsc();
141 
142 	comm2 = "Test COMM 2";
143 	CHECK__(prctl(PR_SET_NAME, (unsigned long)comm2, 0, 0, 0));
144 
145 	evlist__disable(evlist);
146 
147 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
148 		md = &evlist->mmap[i];
149 		if (perf_mmap__read_init(&md->core) < 0)
150 			continue;
151 
152 		while ((event = perf_mmap__read_event(&md->core)) != NULL) {
153 			struct perf_sample sample;
154 
155 			if (event->header.type != PERF_RECORD_COMM ||
156 			    (pid_t)event->comm.pid != getpid() ||
157 			    (pid_t)event->comm.tid != getpid())
158 				goto next_event;
159 
160 			if (strcmp(event->comm.comm, comm1) == 0) {
161 				CHECK_NOT_NULL__(evsel = evlist__event2evsel(evlist, event));
162 				CHECK__(evsel__parse_sample(evsel, event, &sample));
163 				comm1_time = sample.time;
164 			}
165 			if (strcmp(event->comm.comm, comm2) == 0) {
166 				CHECK_NOT_NULL__(evsel = evlist__event2evsel(evlist, event));
167 				CHECK__(evsel__parse_sample(evsel, event, &sample));
168 				comm2_time = sample.time;
169 			}
170 next_event:
171 			perf_mmap__consume(&md->core);
172 		}
173 		perf_mmap__read_done(&md->core);
174 	}
175 
176 	if (!comm1_time || !comm2_time)
177 		goto out_err;
178 
179 	test_time = tsc_to_perf_time(test_tsc, &tc);
180 	comm1_tsc = perf_time_to_tsc(comm1_time, &tc);
181 	comm2_tsc = perf_time_to_tsc(comm2_time, &tc);
182 
183 	pr_debug("1st event perf time %"PRIu64" tsc %"PRIu64"\n",
184 		 comm1_time, comm1_tsc);
185 	pr_debug("rdtsc          time %"PRIu64" tsc %"PRIu64"\n",
186 		 test_time, test_tsc);
187 	pr_debug("2nd event perf time %"PRIu64" tsc %"PRIu64"\n",
188 		 comm2_time, comm2_tsc);
189 
190 	if (test_time <= comm1_time ||
191 	    test_time >= comm2_time)
192 		goto out_err;
193 
194 	if (test_tsc <= comm1_tsc ||
195 	    test_tsc >= comm2_tsc)
196 		goto out_err;
197 
198 	err = TEST_OK;
199 
200 out_err:
201 	evlist__delete(evlist);
202 	perf_cpu_map__put(cpus);
203 	perf_thread_map__put(threads);
204 	return err;
205 }
206 
207 static struct test_case time_to_tsc_tests[] = {
208 	TEST_CASE_REASON("TSC support", tsc_is_supported,
209 			 "This architecture does not support"),
210 	TEST_CASE_REASON("Perf time to TSC", perf_time_to_tsc,
211 			 "perf_read_tsc_conversion is not supported"),
212 	{ .name = NULL, }
213 };
214 
215 struct test_suite suite__perf_time_to_tsc = {
216 	.desc = "Convert perf time to TSC",
217 	.test_cases = time_to_tsc_tests,
218 };
219