1 #include <stdio.h>
2 #include <sys/types.h>
3 #include <unistd.h>
4 #include <inttypes.h>
5 #include <sys/prctl.h>
6 
7 #include "parse-events.h"
8 #include "evlist.h"
9 #include "evsel.h"
10 #include "thread_map.h"
11 #include "cpumap.h"
12 #include "tests.h"
13 
14 #include "../arch/x86/util/tsc.h"
15 
16 #define CHECK__(x) {				\
17 	while ((x) < 0) {			\
18 		pr_debug(#x " failed!\n");	\
19 		goto out_err;			\
20 	}					\
21 }
22 
23 #define CHECK_NOT_NULL__(x) {			\
24 	while ((x) == NULL) {			\
25 		pr_debug(#x " failed!\n");	\
26 		goto out_err;			\
27 	}					\
28 }
29 
30 static u64 rdtsc(void)
31 {
32 	unsigned int low, high;
33 
34 	asm volatile("rdtsc" : "=a" (low), "=d" (high));
35 
36 	return low | ((u64)high) << 32;
37 }
38 
39 /**
40  * test__perf_time_to_tsc - test converting perf time to TSC.
41  *
42  * This function implements a test that checks that the conversion of perf time
43  * to and from TSC is consistent with the order of events.  If the test passes
44  * %0 is returned, otherwise %-1 is returned.  If TSC conversion is not
45  * supported then then the test passes but " (not supported)" is printed.
46  */
47 int test__perf_time_to_tsc(void)
48 {
49 	struct perf_record_opts opts = {
50 		.mmap_pages	     = UINT_MAX,
51 		.user_freq	     = UINT_MAX,
52 		.user_interval	     = ULLONG_MAX,
53 		.freq		     = 4000,
54 		.target		     = {
55 			.uses_mmap   = true,
56 		},
57 		.sample_time	     = true,
58 	};
59 	struct thread_map *threads = NULL;
60 	struct cpu_map *cpus = NULL;
61 	struct perf_evlist *evlist = NULL;
62 	struct perf_evsel *evsel = NULL;
63 	int err = -1, ret, i;
64 	const char *comm1, *comm2;
65 	struct perf_tsc_conversion tc;
66 	struct perf_event_mmap_page *pc;
67 	union perf_event *event;
68 	u64 test_tsc, comm1_tsc, comm2_tsc;
69 	u64 test_time, comm1_time = 0, comm2_time = 0;
70 
71 	threads = thread_map__new(-1, getpid(), UINT_MAX);
72 	CHECK_NOT_NULL__(threads);
73 
74 	cpus = cpu_map__new(NULL);
75 	CHECK_NOT_NULL__(cpus);
76 
77 	evlist = perf_evlist__new();
78 	CHECK_NOT_NULL__(evlist);
79 
80 	perf_evlist__set_maps(evlist, cpus, threads);
81 
82 	CHECK__(parse_events(evlist, "cycles:u"));
83 
84 	perf_evlist__config(evlist, &opts);
85 
86 	evsel = perf_evlist__first(evlist);
87 
88 	evsel->attr.comm = 1;
89 	evsel->attr.disabled = 1;
90 	evsel->attr.enable_on_exec = 0;
91 
92 	CHECK__(perf_evlist__open(evlist));
93 
94 	CHECK__(perf_evlist__mmap(evlist, UINT_MAX, false));
95 
96 	pc = evlist->mmap[0].base;
97 	ret = perf_read_tsc_conversion(pc, &tc);
98 	if (ret) {
99 		if (ret == -EOPNOTSUPP) {
100 			fprintf(stderr, " (not supported)");
101 			return 0;
102 		}
103 		goto out_err;
104 	}
105 
106 	perf_evlist__enable(evlist);
107 
108 	comm1 = "Test COMM 1";
109 	CHECK__(prctl(PR_SET_NAME, (unsigned long)comm1, 0, 0, 0));
110 
111 	test_tsc = rdtsc();
112 
113 	comm2 = "Test COMM 2";
114 	CHECK__(prctl(PR_SET_NAME, (unsigned long)comm2, 0, 0, 0));
115 
116 	perf_evlist__disable(evlist);
117 
118 	for (i = 0; i < evlist->nr_mmaps; i++) {
119 		while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
120 			struct perf_sample sample;
121 
122 			if (event->header.type != PERF_RECORD_COMM ||
123 			    (pid_t)event->comm.pid != getpid() ||
124 			    (pid_t)event->comm.tid != getpid())
125 				goto next_event;
126 
127 			if (strcmp(event->comm.comm, comm1) == 0) {
128 				CHECK__(perf_evsel__parse_sample(evsel, event,
129 								 &sample));
130 				comm1_time = sample.time;
131 			}
132 			if (strcmp(event->comm.comm, comm2) == 0) {
133 				CHECK__(perf_evsel__parse_sample(evsel, event,
134 								 &sample));
135 				comm2_time = sample.time;
136 			}
137 next_event:
138 			perf_evlist__mmap_consume(evlist, i);
139 		}
140 	}
141 
142 	if (!comm1_time || !comm2_time)
143 		goto out_err;
144 
145 	test_time = tsc_to_perf_time(test_tsc, &tc);
146 	comm1_tsc = perf_time_to_tsc(comm1_time, &tc);
147 	comm2_tsc = perf_time_to_tsc(comm2_time, &tc);
148 
149 	pr_debug("1st event perf time %"PRIu64" tsc %"PRIu64"\n",
150 		 comm1_time, comm1_tsc);
151 	pr_debug("rdtsc          time %"PRIu64" tsc %"PRIu64"\n",
152 		 test_time, test_tsc);
153 	pr_debug("2nd event perf time %"PRIu64" tsc %"PRIu64"\n",
154 		 comm2_time, comm2_tsc);
155 
156 	if (test_time <= comm1_time ||
157 	    test_time >= comm2_time)
158 		goto out_err;
159 
160 	if (test_tsc <= comm1_tsc ||
161 	    test_tsc >= comm2_tsc)
162 		goto out_err;
163 
164 	err = 0;
165 
166 out_err:
167 	if (evlist) {
168 		perf_evlist__disable(evlist);
169 		perf_evlist__munmap(evlist);
170 		perf_evlist__close(evlist);
171 		perf_evlist__delete(evlist);
172 	}
173 	if (cpus)
174 		cpu_map__delete(cpus);
175 	if (threads)
176 		thread_map__delete(threads);
177 
178 	return err;
179 }
180