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 "perf.h"
  28 #include "cloexec.h"
  29
  30 static int overflows;
  31
  32 static noinline int test_function(void)
  33 {
  34         return time(NULL);
  35 }
  36
  37 static void sig_handler(int signum __maybe_unused,
  38                         siginfo_t *oh __maybe_unused,
  39                         void *uc __maybe_unused)
  40 {
  41         overflows++;
  42 }
  43
  44 static long long bp_count(int fd)
  45 {
  46         long long count;
  47         int ret;
  48
  49         ret = read(fd, &count, sizeof(long long));
  50         if (ret != sizeof(long long)) {
  51                 pr_debug("failed to read: %d\n", ret);
  52                 return TEST_FAIL;
  53         }
  54
  55         return count;
  56 }
  57
  58 #define EXECUTIONS 10000
  59 #define THRESHOLD  100
  60
  61 int test__bp_signal_overflow(struct test *test __maybe_unused, int subtest __maybe_unused)
  62 {
  63         struct perf_event_attr pe;
  64         struct sigaction sa;
  65         long long count;
  66         int fd, i, fails = 0;
  67
  68         /* setup SIGIO signal handler */
  69         memset(&sa, 0, sizeof(struct sigaction));
  70         sa.sa_sigaction = (void *) sig_handler;
  71         sa.sa_flags = SA_SIGINFO;
  72
  73         if (sigaction(SIGIO, &sa, NULL) < 0) {
  74                 pr_debug("failed setting up signal handler\n");
  75                 return TEST_FAIL;
  76         }
  77
  78         memset(&pe, 0, sizeof(struct perf_event_attr));
  79         pe.type = PERF_TYPE_BREAKPOINT;
  80         pe.size = sizeof(struct perf_event_attr);
  81
  82         pe.config = 0;
  83         pe.bp_type = HW_BREAKPOINT_X;
  84         pe.bp_addr = (unsigned long) test_function;
  85         pe.bp_len = sizeof(long);
  86
  87         pe.sample_period = THRESHOLD;
  88         pe.sample_type = PERF_SAMPLE_IP;
  89         pe.wakeup_events = 1;
  90
  91         pe.disabled = 1;
  92         pe.exclude_kernel = 1;
  93         pe.exclude_hv = 1;
  94
  95         fd = sys_perf_event_open(&pe, 0, -1, -1,
  96                                  perf_event_open_cloexec_flag());
  97         if (fd < 0) {
  98                 pr_debug("failed opening event %llx\n", pe.config);
  99                 return TEST_FAIL;
 100         }
 101
 102         fcntl(fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC);
 103         fcntl(fd, F_SETSIG, SIGIO);
 104         fcntl(fd, F_SETOWN, getpid());
 105
 106         ioctl(fd, PERF_EVENT_IOC_RESET, 0);
 107         ioctl(fd, PERF_EVENT_IOC_ENABLE, 0);
 108
 109         for (i = 0; i < EXECUTIONS; i++)
 110                 test_function();
 111
 112         ioctl(fd, PERF_EVENT_IOC_DISABLE, 0);
 113
 114         count = bp_count(fd);
 115
 116         close(fd);
 117
 118         pr_debug("count %lld, overflow %d\n",
 119                  count, overflows);
 120
 121         if (count != EXECUTIONS) {
 122                 pr_debug("\tWrong number of executions %lld != %d\n",
 123                 count, EXECUTIONS);
 124                 fails++;
 125         }
 126
 127         if (overflows != EXECUTIONS / THRESHOLD) {
 128                 pr_debug("\tWrong number of overflows %d != %d\n",
 129                 overflows, EXECUTIONS / THRESHOLD);
 130                 fails++;
 131         }
 132
 133         return fails ? TEST_FAIL : TEST_OK;
 134 }