tools: Consolidate types.h
[deliverable/linux.git] / tools / perf / tests / rdpmc.c
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1#include <unistd.h>
2#include <stdlib.h>
3#include <signal.h>
4#include <sys/mman.h>
d944c4ee 5#include <linux/types.h>
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6#include "perf.h"
7#include "debug.h"
8#include "tests.h"
9
10#if defined(__x86_64__) || defined(__i386__)
11
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12static u64 rdpmc(unsigned int counter)
13{
14 unsigned int low, high;
15
16 asm volatile("rdpmc" : "=a" (low), "=d" (high) : "c" (counter));
17
18 return low | ((u64)high) << 32;
19}
20
21static u64 rdtsc(void)
22{
23 unsigned int low, high;
24
25 asm volatile("rdtsc" : "=a" (low), "=d" (high));
26
27 return low | ((u64)high) << 32;
28}
29
30static u64 mmap_read_self(void *addr)
31{
32 struct perf_event_mmap_page *pc = addr;
33 u32 seq, idx, time_mult = 0, time_shift = 0;
34 u64 count, cyc = 0, time_offset = 0, enabled, running, delta;
35
36 do {
37 seq = pc->lock;
38 barrier();
39
40 enabled = pc->time_enabled;
41 running = pc->time_running;
42
43 if (enabled != running) {
44 cyc = rdtsc();
45 time_mult = pc->time_mult;
46 time_shift = pc->time_shift;
47 time_offset = pc->time_offset;
48 }
49
50 idx = pc->index;
51 count = pc->offset;
52 if (idx)
53 count += rdpmc(idx - 1);
54
55 barrier();
56 } while (pc->lock != seq);
57
58 if (enabled != running) {
59 u64 quot, rem;
60
61 quot = (cyc >> time_shift);
62 rem = cyc & ((1 << time_shift) - 1);
63 delta = time_offset + quot * time_mult +
64 ((rem * time_mult) >> time_shift);
65
66 enabled += delta;
67 if (idx)
68 running += delta;
69
70 quot = count / running;
71 rem = count % running;
72 count = quot * enabled + (rem * enabled) / running;
73 }
74
75 return count;
76}
77
78/*
79 * If the RDPMC instruction faults then signal this back to the test parent task:
80 */
81static void segfault_handler(int sig __maybe_unused,
82 siginfo_t *info __maybe_unused,
83 void *uc __maybe_unused)
84{
85 exit(-1);
86}
87
88static int __test__rdpmc(void)
89{
90 volatile int tmp = 0;
91 u64 i, loops = 1000;
92 int n;
93 int fd;
94 void *addr;
95 struct perf_event_attr attr = {
96 .type = PERF_TYPE_HARDWARE,
97 .config = PERF_COUNT_HW_INSTRUCTIONS,
98 .exclude_kernel = 1,
99 };
100 u64 delta_sum = 0;
101 struct sigaction sa;
102
103 sigfillset(&sa.sa_mask);
104 sa.sa_sigaction = segfault_handler;
105 sigaction(SIGSEGV, &sa, NULL);
106
107 fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
108 if (fd < 0) {
109 pr_err("Error: sys_perf_event_open() syscall returned "
110 "with %d (%s)\n", fd, strerror(errno));
111 return -1;
112 }
113
114 addr = mmap(NULL, page_size, PROT_READ, MAP_SHARED, fd, 0);
115 if (addr == (void *)(-1)) {
116 pr_err("Error: mmap() syscall returned with (%s)\n",
117 strerror(errno));
118 goto out_close;
119 }
120
121 for (n = 0; n < 6; n++) {
122 u64 stamp, now, delta;
123
124 stamp = mmap_read_self(addr);
125
126 for (i = 0; i < loops; i++)
127 tmp++;
128
129 now = mmap_read_self(addr);
130 loops *= 10;
131
132 delta = now - stamp;
133 pr_debug("%14d: %14Lu\n", n, (long long)delta);
134
135 delta_sum += delta;
136 }
137
138 munmap(addr, page_size);
139 pr_debug(" ");
140out_close:
141 close(fd);
142
143 if (!delta_sum)
144 return -1;
145
146 return 0;
147}
148
149int test__rdpmc(void)
150{
151 int status = 0;
152 int wret = 0;
153 int ret;
154 int pid;
155
156 pid = fork();
157 if (pid < 0)
158 return -1;
159
160 if (!pid) {
161 ret = __test__rdpmc();
162
163 exit(ret);
164 }
165
166 wret = waitpid(pid, &status, 0);
167 if (wret < 0 || status)
168 return -1;
169
170 return 0;
171}
172
173#endif
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