1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * User Events Perf Events Test Program 4 * 5 * Copyright (c) 2021 Beau Belgrave <beaub@linux.microsoft.com> 6 */ 7 8 #include <errno.h> 9 #include <linux/user_events.h> 10 #include <linux/perf_event.h> 11 #include <stdio.h> 12 #include <stdlib.h> 13 #include <fcntl.h> 14 #include <sys/ioctl.h> 15 #include <sys/stat.h> 16 #include <unistd.h> 17 #include <asm/unistd.h> 18 19 #include "../kselftest_harness.h" 20 21 const char *data_file = "/sys/kernel/tracing/user_events_data"; 22 const char *id_file = "/sys/kernel/tracing/events/user_events/__test_event/id"; 23 const char *fmt_file = "/sys/kernel/tracing/events/user_events/__test_event/format"; 24 25 struct event { 26 __u32 index; 27 __u32 field1; 28 __u32 field2; 29 }; 30 31 static long perf_event_open(struct perf_event_attr *pe, pid_t pid, 32 int cpu, int group_fd, unsigned long flags) 33 { 34 return syscall(__NR_perf_event_open, pe, pid, cpu, group_fd, flags); 35 } 36 37 static int get_id(void) 38 { 39 FILE *fp = fopen(id_file, "r"); 40 int ret, id = 0; 41 42 if (!fp) 43 return -1; 44 45 ret = fscanf(fp, "%d", &id); 46 fclose(fp); 47 48 if (ret != 1) 49 return -1; 50 51 return id; 52 } 53 54 static int get_offset(void) 55 { 56 FILE *fp = fopen(fmt_file, "r"); 57 int ret, c, last = 0, offset = 0; 58 59 if (!fp) 60 return -1; 61 62 /* Read until empty line */ 63 while (true) { 64 c = getc(fp); 65 66 if (c == EOF) 67 break; 68 69 if (last == '\n' && c == '\n') 70 break; 71 72 last = c; 73 } 74 75 ret = fscanf(fp, "\tfield:u32 field1;\toffset:%d;", &offset); 76 fclose(fp); 77 78 if (ret != 1) 79 return -1; 80 81 return offset; 82 } 83 84 FIXTURE(user) { 85 int data_fd; 86 int check; 87 }; 88 89 FIXTURE_SETUP(user) { 90 self->data_fd = open(data_file, O_RDWR); 91 ASSERT_NE(-1, self->data_fd); 92 } 93 94 FIXTURE_TEARDOWN(user) { 95 close(self->data_fd); 96 } 97 98 TEST_F(user, perf_write) { 99 struct perf_event_attr pe = {0}; 100 struct user_reg reg = {0}; 101 struct event event; 102 struct perf_event_mmap_page *perf_page; 103 int page_size = sysconf(_SC_PAGESIZE); 104 int id, fd, offset; 105 __u32 *val; 106 107 reg.size = sizeof(reg); 108 reg.name_args = (__u64)"__test_event u32 field1; u32 field2"; 109 reg.enable_bit = 31; 110 reg.enable_addr = (__u64)&self->check; 111 reg.enable_size = sizeof(self->check); 112 113 /* Register should work */ 114 ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, ®)); 115 ASSERT_EQ(0, reg.write_index); 116 ASSERT_EQ(0, self->check); 117 118 /* Id should be there */ 119 id = get_id(); 120 ASSERT_NE(-1, id); 121 offset = get_offset(); 122 ASSERT_NE(-1, offset); 123 124 pe.type = PERF_TYPE_TRACEPOINT; 125 pe.size = sizeof(pe); 126 pe.config = id; 127 pe.sample_type = PERF_SAMPLE_RAW; 128 pe.sample_period = 1; 129 pe.wakeup_events = 1; 130 131 /* Tracepoint attach should work */ 132 fd = perf_event_open(&pe, 0, -1, -1, 0); 133 ASSERT_NE(-1, fd); 134 135 perf_page = mmap(NULL, page_size * 2, PROT_READ, MAP_SHARED, fd, 0); 136 ASSERT_NE(MAP_FAILED, perf_page); 137 138 /* Status should be updated */ 139 ASSERT_EQ(1 << reg.enable_bit, self->check); 140 141 event.index = reg.write_index; 142 event.field1 = 0xc001; 143 event.field2 = 0xc01a; 144 145 /* Ensure write shows up at correct offset */ 146 ASSERT_NE(-1, write(self->data_fd, &event, sizeof(event))); 147 val = (void *)(((char *)perf_page) + perf_page->data_offset); 148 ASSERT_EQ(PERF_RECORD_SAMPLE, *val); 149 /* Skip over header and size, move to offset */ 150 val += 3; 151 val = (void *)((char *)val) + offset; 152 /* Ensure correct */ 153 ASSERT_EQ(event.field1, *val++); 154 ASSERT_EQ(event.field2, *val++); 155 156 munmap(perf_page, page_size * 2); 157 close(fd); 158 159 /* Status should be updated */ 160 ASSERT_EQ(0, self->check); 161 } 162 163 int main(int argc, char **argv) 164 { 165 return test_harness_run(argc, argv); 166 } 167