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 #include "pmu.h"
24 #include "pmu-hybrid.h"
25 
26 /*
27  * Except x86_64/i386 and Arm64, other archs don't support TSC in perf.  Just
28  * enable the test for x86_64/i386 and Arm64 archs.
29  */
30 #if defined(__x86_64__) || defined(__i386__) || defined(__aarch64__)
31 #define TSC_IS_SUPPORTED 1
32 #else
33 #define TSC_IS_SUPPORTED 0
34 #endif
35 
36 #define CHECK__(x) {				\
37 	while ((x) < 0) {			\
38 		pr_debug(#x " failed!\n");	\
39 		goto out_err;			\
40 	}					\
41 }
42 
43 #define CHECK_NOT_NULL__(x) {			\
44 	while ((x) == NULL) {			\
45 		pr_debug(#x " failed!\n");	\
46 		goto out_err;			\
47 	}					\
48 }
49 
50 /**
51  * test__perf_time_to_tsc - test converting perf time to TSC.
52  *
53  * This function implements a test that checks that the conversion of perf time
54  * to and from TSC is consistent with the order of events.  If the test passes
55  * %0 is returned, otherwise %-1 is returned.  If TSC conversion is not
56  * supported then then the test passes but " (not supported)" is printed.
57  */
test__perf_time_to_tsc(struct test_suite * test __maybe_unused,int subtest __maybe_unused)58 static int test__perf_time_to_tsc(struct test_suite *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 		.sample_time	     = true,
68 	};
69 	struct perf_thread_map *threads = NULL;
70 	struct perf_cpu_map *cpus = NULL;
71 	struct evlist *evlist = NULL;
72 	struct evsel *evsel = NULL;
73 	int err = -1, ret, i;
74 	const char *comm1, *comm2;
75 	struct perf_tsc_conversion tc;
76 	struct perf_event_mmap_page *pc;
77 	union perf_event *event;
78 	u64 test_tsc, comm1_tsc, comm2_tsc;
79 	u64 test_time, comm1_time = 0, comm2_time = 0;
80 	struct mmap *md;
81 
82 	if (!TSC_IS_SUPPORTED) {
83 		pr_debug("Test not supported on this architecture");
84 		return TEST_SKIP;
85 	}
86 
87 	threads = thread_map__new(-1, getpid(), UINT_MAX);
88 	CHECK_NOT_NULL__(threads);
89 
90 	cpus = perf_cpu_map__new(NULL);
91 	CHECK_NOT_NULL__(cpus);
92 
93 	evlist = evlist__new();
94 	CHECK_NOT_NULL__(evlist);
95 
96 	perf_evlist__set_maps(&evlist->core, cpus, threads);
97 
98 	CHECK__(parse_events(evlist, "cycles:u", NULL));
99 
100 	evlist__config(evlist, &opts, NULL);
101 
102 	evsel = evlist__first(evlist);
103 
104 	evsel->core.attr.comm = 1;
105 	evsel->core.attr.disabled = 1;
106 	evsel->core.attr.enable_on_exec = 0;
107 
108 	/*
109 	 * For hybrid "cycles:u", it creates two events.
110 	 * Init the second evsel here.
111 	 */
112 	if (perf_pmu__has_hybrid() && perf_pmu__hybrid_mounted("cpu_atom")) {
113 		evsel = evsel__next(evsel);
114 		evsel->core.attr.comm = 1;
115 		evsel->core.attr.disabled = 1;
116 		evsel->core.attr.enable_on_exec = 0;
117 	}
118 
119 	CHECK__(evlist__open(evlist));
120 
121 	CHECK__(evlist__mmap(evlist, UINT_MAX));
122 
123 	pc = evlist->mmap[0].core.base;
124 	ret = perf_read_tsc_conversion(pc, &tc);
125 	if (ret) {
126 		if (ret == -EOPNOTSUPP) {
127 			fprintf(stderr, " (not supported)");
128 			return 0;
129 		}
130 		goto out_err;
131 	}
132 
133 	evlist__enable(evlist);
134 
135 	comm1 = "Test COMM 1";
136 	CHECK__(prctl(PR_SET_NAME, (unsigned long)comm1, 0, 0, 0));
137 
138 	test_tsc = rdtsc();
139 
140 	comm2 = "Test COMM 2";
141 	CHECK__(prctl(PR_SET_NAME, (unsigned long)comm2, 0, 0, 0));
142 
143 	evlist__disable(evlist);
144 
145 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
146 		md = &evlist->mmap[i];
147 		if (perf_mmap__read_init(&md->core) < 0)
148 			continue;
149 
150 		while ((event = perf_mmap__read_event(&md->core)) != NULL) {
151 			struct perf_sample sample;
152 
153 			if (event->header.type != PERF_RECORD_COMM ||
154 			    (pid_t)event->comm.pid != getpid() ||
155 			    (pid_t)event->comm.tid != getpid())
156 				goto next_event;
157 
158 			if (strcmp(event->comm.comm, comm1) == 0) {
159 				CHECK__(evsel__parse_sample(evsel, event, &sample));
160 				comm1_time = sample.time;
161 			}
162 			if (strcmp(event->comm.comm, comm2) == 0) {
163 				CHECK__(evsel__parse_sample(evsel, event, &sample));
164 				comm2_time = sample.time;
165 			}
166 next_event:
167 			perf_mmap__consume(&md->core);
168 		}
169 		perf_mmap__read_done(&md->core);
170 	}
171 
172 	if (!comm1_time || !comm2_time)
173 		goto out_err;
174 
175 	test_time = tsc_to_perf_time(test_tsc, &tc);
176 	comm1_tsc = perf_time_to_tsc(comm1_time, &tc);
177 	comm2_tsc = perf_time_to_tsc(comm2_time, &tc);
178 
179 	pr_debug("1st event perf time %"PRIu64" tsc %"PRIu64"\n",
180 		 comm1_time, comm1_tsc);
181 	pr_debug("rdtsc          time %"PRIu64" tsc %"PRIu64"\n",
182 		 test_time, test_tsc);
183 	pr_debug("2nd event perf time %"PRIu64" tsc %"PRIu64"\n",
184 		 comm2_time, comm2_tsc);
185 
186 	if (test_time <= comm1_time ||
187 	    test_time >= comm2_time)
188 		goto out_err;
189 
190 	if (test_tsc <= comm1_tsc ||
191 	    test_tsc >= comm2_tsc)
192 		goto out_err;
193 
194 	err = 0;
195 
196 out_err:
197 	evlist__delete(evlist);
198 	perf_cpu_map__put(cpus);
199 	perf_thread_map__put(threads);
200 	return err;
201 }
202 
203 DEFINE_SUITE("Convert perf time to TSC", perf_time_to_tsc);
204