1 /* 2 * Originally done by Vince Weaver <vincent.weaver@maine.edu> for 3 * perf_event_tests (git://github.com/deater/perf_event_tests) 4 */ 5 6 #include <stdlib.h> 7 #include <stdio.h> 8 #include <unistd.h> 9 #include <string.h> 10 #include <sys/ioctl.h> 11 #include <time.h> 12 #include <fcntl.h> 13 #include <signal.h> 14 #include <sys/mman.h> 15 #include <linux/compiler.h> 16 #include <linux/hw_breakpoint.h> 17 18 #include "tests.h" 19 #include "debug.h" 20 #include "perf.h" 21 22 static int overflows; 23 24 __attribute__ ((noinline)) 25 static int test_function(void) 26 { 27 return time(NULL); 28 } 29 30 static void sig_handler(int signum __maybe_unused, 31 siginfo_t *oh __maybe_unused, 32 void *uc __maybe_unused) 33 { 34 overflows++; 35 } 36 37 static long long bp_count(int fd) 38 { 39 long long count; 40 int ret; 41 42 ret = read(fd, &count, sizeof(long long)); 43 if (ret != sizeof(long long)) { 44 pr_debug("failed to read: %d\n", ret); 45 return TEST_FAIL; 46 } 47 48 return count; 49 } 50 51 #define EXECUTIONS 10000 52 #define THRESHOLD 100 53 54 int test__bp_signal_overflow(void) 55 { 56 struct perf_event_attr pe; 57 struct sigaction sa; 58 long long count; 59 int fd, i, fails = 0; 60 61 /* setup SIGIO signal handler */ 62 memset(&sa, 0, sizeof(struct sigaction)); 63 sa.sa_sigaction = (void *) sig_handler; 64 sa.sa_flags = SA_SIGINFO; 65 66 if (sigaction(SIGIO, &sa, NULL) < 0) { 67 pr_debug("failed setting up signal handler\n"); 68 return TEST_FAIL; 69 } 70 71 memset(&pe, 0, sizeof(struct perf_event_attr)); 72 pe.type = PERF_TYPE_BREAKPOINT; 73 pe.size = sizeof(struct perf_event_attr); 74 75 pe.config = 0; 76 pe.bp_type = HW_BREAKPOINT_X; 77 pe.bp_addr = (unsigned long) test_function; 78 pe.bp_len = sizeof(long); 79 80 pe.sample_period = THRESHOLD; 81 pe.sample_type = PERF_SAMPLE_IP; 82 pe.wakeup_events = 1; 83 84 pe.disabled = 1; 85 pe.exclude_kernel = 1; 86 pe.exclude_hv = 1; 87 88 fd = sys_perf_event_open(&pe, 0, -1, -1, 0); 89 if (fd < 0) { 90 pr_debug("failed opening event %llx\n", pe.config); 91 return TEST_FAIL; 92 } 93 94 fcntl(fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC); 95 fcntl(fd, F_SETSIG, SIGIO); 96 fcntl(fd, F_SETOWN, getpid()); 97 98 ioctl(fd, PERF_EVENT_IOC_RESET, 0); 99 ioctl(fd, PERF_EVENT_IOC_ENABLE, 0); 100 101 for (i = 0; i < EXECUTIONS; i++) 102 test_function(); 103 104 ioctl(fd, PERF_EVENT_IOC_DISABLE, 0); 105 106 count = bp_count(fd); 107 108 close(fd); 109 110 pr_debug("count %lld, overflow %d\n", 111 count, overflows); 112 113 if (count != EXECUTIONS) { 114 pr_debug("\tWrong number of executions %lld != %d\n", 115 count, EXECUTIONS); 116 fails++; 117 } 118 119 if (overflows != EXECUTIONS / THRESHOLD) { 120 pr_debug("\tWrong number of overflows %d != %d\n", 121 overflows, EXECUTIONS / THRESHOLD); 122 fails++; 123 } 124 125 return fails ? TEST_FAIL : TEST_OK; 126 } 127