1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Originally done by Vince Weaver <vincent.weaver@maine.edu> for 4 * perf_event_tests (git://github.com/deater/perf_event_tests) 5 */ 6 7 /* 8 * Powerpc needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select 9 * 'int-ll64.h' and avoid compile warnings when printing __u64 with %llu. 10 */ 11 #define __SANE_USERSPACE_TYPES__ 12 13 #include <stdlib.h> 14 #include <stdio.h> 15 #include <unistd.h> 16 #include <string.h> 17 #include <sys/ioctl.h> 18 #include <time.h> 19 #include <fcntl.h> 20 #include <signal.h> 21 #include <sys/mman.h> 22 #include <linux/compiler.h> 23 #include <linux/hw_breakpoint.h> 24 25 #include "tests.h" 26 #include "debug.h" 27 #include "event.h" 28 #include "../perf-sys.h" 29 #include "cloexec.h" 30 31 static int overflows; 32 33 static noinline int test_function(void) 34 { 35 return time(NULL); 36 } 37 38 static void sig_handler(int signum __maybe_unused, 39 siginfo_t *oh __maybe_unused, 40 void *uc __maybe_unused) 41 { 42 overflows++; 43 } 44 45 static long long bp_count(int fd) 46 { 47 long long count; 48 int ret; 49 50 ret = read(fd, &count, sizeof(long long)); 51 if (ret != sizeof(long long)) { 52 pr_debug("failed to read: %d\n", ret); 53 return TEST_FAIL; 54 } 55 56 return count; 57 } 58 59 #define EXECUTIONS 10000 60 #define THRESHOLD 100 61 62 static int test__bp_signal_overflow(struct test_suite *test __maybe_unused, int subtest __maybe_unused) 63 { 64 struct perf_event_attr pe; 65 struct sigaction sa; 66 long long count; 67 int fd, i, fails = 0; 68 69 if (!BP_SIGNAL_IS_SUPPORTED) { 70 pr_debug("Test not supported on this architecture"); 71 return TEST_SKIP; 72 } 73 74 /* setup SIGIO signal handler */ 75 memset(&sa, 0, sizeof(struct sigaction)); 76 sa.sa_sigaction = (void *) sig_handler; 77 sa.sa_flags = SA_SIGINFO; 78 79 if (sigaction(SIGIO, &sa, NULL) < 0) { 80 pr_debug("failed setting up signal handler\n"); 81 return TEST_FAIL; 82 } 83 84 memset(&pe, 0, sizeof(struct perf_event_attr)); 85 pe.type = PERF_TYPE_BREAKPOINT; 86 pe.size = sizeof(struct perf_event_attr); 87 88 pe.config = 0; 89 pe.bp_type = HW_BREAKPOINT_X; 90 pe.bp_addr = (unsigned long) test_function; 91 pe.bp_len = sizeof(long); 92 93 pe.sample_period = THRESHOLD; 94 pe.sample_type = PERF_SAMPLE_IP; 95 pe.wakeup_events = 1; 96 97 pe.disabled = 1; 98 pe.exclude_kernel = 1; 99 pe.exclude_hv = 1; 100 101 fd = sys_perf_event_open(&pe, 0, -1, -1, 102 perf_event_open_cloexec_flag()); 103 if (fd < 0) { 104 pr_debug("failed opening event %llx\n", pe.config); 105 return TEST_FAIL; 106 } 107 108 fcntl(fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC); 109 fcntl(fd, F_SETSIG, SIGIO); 110 fcntl(fd, F_SETOWN, getpid()); 111 112 ioctl(fd, PERF_EVENT_IOC_RESET, 0); 113 ioctl(fd, PERF_EVENT_IOC_ENABLE, 0); 114 115 for (i = 0; i < EXECUTIONS; i++) 116 test_function(); 117 118 ioctl(fd, PERF_EVENT_IOC_DISABLE, 0); 119 120 count = bp_count(fd); 121 122 close(fd); 123 124 pr_debug("count %lld, overflow %d\n", 125 count, overflows); 126 127 if (count != EXECUTIONS) { 128 pr_debug("\tWrong number of executions %lld != %d\n", 129 count, EXECUTIONS); 130 fails++; 131 } 132 133 if (overflows != EXECUTIONS / THRESHOLD) { 134 pr_debug("\tWrong number of overflows %d != %d\n", 135 overflows, EXECUTIONS / THRESHOLD); 136 fails++; 137 } 138 139 return fails ? TEST_FAIL : TEST_OK; 140 } 141 142 DEFINE_SUITE("Breakpoint overflow sampling", bp_signal_overflow); 143