tools/perf/tests/bp_signal_overflow.c

   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 "parse-events.h"
  29 #include "../perf-sys.h"
  30 #include "cloexec.h"
  31
  32 static int overflows;
  33
  34 static noinline int test_function(void)
  35 {
  36         return time(NULL);
  37 }
  38
  39 static void sig_handler(int signum __maybe_unused,
  40                         siginfo_t *oh __maybe_unused,
  41                         void *uc __maybe_unused)
  42 {
  43         overflows++;
  44 }
  45
  46 static long long bp_count(int fd)
  47 {
  48         long long count;
  49         int ret;
  50
  51         ret = read(fd, &count, sizeof(long long));
  52         if (ret != sizeof(long long)) {
  53                 pr_debug("failed to read: %d\n", ret);
  54                 return TEST_FAIL;
  55         }
  56
  57         return count;
  58 }
  59
  60 #define EXECUTIONS 10000
  61 #define THRESHOLD  100
  62
  63 static int test__bp_signal_overflow(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
  64 {
  65         struct perf_event_attr pe;
  66         struct sigaction sa;
  67         long long count;
  68         int fd, i, fails = 0;
  69
  70         if (!BP_SIGNAL_IS_SUPPORTED) {
  71                 pr_debug("Test not supported on this architecture");
  72                 return TEST_SKIP;
  73         }
  74
  75         /* setup SIGIO signal handler */
  76         memset(&sa, 0, sizeof(struct sigaction));
  77         sa.sa_sigaction = (void *) sig_handler;
  78         sa.sa_flags = SA_SIGINFO;
  79
  80         if (sigaction(SIGIO, &sa, NULL) < 0) {
  81                 pr_debug("failed setting up signal handler\n");
  82                 return TEST_FAIL;
  83         }
  84
  85         memset(&pe, 0, sizeof(struct perf_event_attr));
  86         pe.type = PERF_TYPE_BREAKPOINT;
  87         pe.size = sizeof(struct perf_event_attr);
  88
  89         pe.config = 0;
  90         pe.bp_type = HW_BREAKPOINT_X;
  91         pe.bp_addr = (unsigned long) test_function;
  92         pe.bp_len = default_breakpoint_len();
  93
  94         pe.sample_period = THRESHOLD;
  95         pe.sample_type = PERF_SAMPLE_IP;
  96         pe.wakeup_events = 1;
  97
  98         pe.disabled = 1;
  99         pe.exclude_kernel = 1;
 100         pe.exclude_hv = 1;
 101
 102         fd = sys_perf_event_open(&pe, 0, -1, -1,
 103                                  perf_event_open_cloexec_flag());
 104         if (fd < 0) {
 105                 pr_debug("failed opening event %llx\n", pe.config);
 106                 return TEST_FAIL;
 107         }
 108
 109         fcntl(fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC);
 110         fcntl(fd, F_SETSIG, SIGIO);
 111         fcntl(fd, F_SETOWN, getpid());
 112
 113         ioctl(fd, PERF_EVENT_IOC_RESET, 0);
 114         ioctl(fd, PERF_EVENT_IOC_ENABLE, 0);
 115
 116         for (i = 0; i < EXECUTIONS; i++)
 117                 test_function();
 118
 119         ioctl(fd, PERF_EVENT_IOC_DISABLE, 0);
 120
 121         count = bp_count(fd);
 122
 123         close(fd);
 124
 125         pr_debug("count %lld, overflow %d\n",
 126                  count, overflows);
 127
 128         if (count != EXECUTIONS) {
 129                 pr_debug("\tWrong number of executions %lld != %d\n",
 130                 count, EXECUTIONS);
 131                 fails++;
 132         }
 133
 134         if (overflows != EXECUTIONS / THRESHOLD) {
 135                 pr_debug("\tWrong number of overflows %d != %d\n",
 136                 overflows, EXECUTIONS / THRESHOLD);
 137                 fails++;
 138         }
 139
 140         return fails ? TEST_FAIL : TEST_OK;
 141 }
 142
 143 DEFINE_SUITE("Breakpoint overflow sampling", bp_signal_overflow);