LXR linux/tools/perf/tests/bp_signal

   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
  22static int overflows;
  23
  24__attribute__ ((noinline))
  25static int test_function(void)
  26{
  27        return time(NULL);
  28}
  29
  30static void sig_handler(int signum __maybe_unused,
  31                        siginfo_t *oh __maybe_unused,
  32                        void *uc __maybe_unused)
  33{
  34        overflows++;
  35}
  36
  37static 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
  54int 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