// SPDX-License-Identifier: GPL-2.0 /* * Originally done by Vince Weaver <vincent.weaver@maine.edu> for * perf_event_tests (git://github.com/deater/perf_event_tests) */ /* * Powerpc needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select * 'int-ll64.h' and avoid compile warnings when printing __u64 with %llu. */ #define __SANE_USERSPACE_TYPES__ #include <stdlib.h> #include <stdio.h> #include <unistd.h> #include <string.h> #include <sys/ioctl.h> #include <time.h> #include <fcntl.h> #include <signal.h> #include <sys/mman.h> #include <linux/compiler.h> #include <linux/hw_breakpoint.h> #include "tests.h" #include "debug.h" #include "event.h" #include "../perf-sys.h" #include "cloexec.h" static int overflows; static noinline int test_function(void) { return time(NULL); } static void sig_handler(int signum __maybe_unused, siginfo_t *oh __maybe_unused, void *uc __maybe_unused) { overflows++; } static long long bp_count(int fd) { long long count; int ret; ret = read(fd, &count, sizeof(long long)); if (ret != sizeof(long long)) { pr_debug("failed to read: %d\n", ret); return TEST_FAIL; } return count; } #define EXECUTIONS 10000 #define THRESHOLD 100 static int test__bp_signal_overflow(struct test_suite *test __maybe_unused, int subtest __maybe_unused) { struct perf_event_attr pe; struct sigaction sa; long long count; int fd, i, fails = 0; if (!BP_SIGNAL_IS_SUPPORTED) { pr_debug("Test not supported on this architecture"); return TEST_SKIP; } /* setup SIGIO signal handler */ memset(&sa, 0, sizeof(struct sigaction)); sa.sa_sigaction = (void *) sig_handler; sa.sa_flags = SA_SIGINFO; if (sigaction(SIGIO, &sa, NULL) < 0) { pr_debug("failed setting up signal handler\n"); return TEST_FAIL; } memset(&pe, 0, sizeof(struct perf_event_attr)); pe.type = PERF_TYPE_BREAKPOINT; pe.size = sizeof(struct perf_event_attr); pe.config = 0; pe.bp_type = HW_BREAKPOINT_X; pe.bp_addr = (unsigned long) test_function; pe.bp_len = sizeof(long); pe.sample_period = THRESHOLD; pe.sample_type = PERF_SAMPLE_IP; pe.wakeup_events = 1; pe.disabled = 1; pe.exclude_kernel = 1; pe.exclude_hv = 1; fd = sys_perf_event_open(&pe, 0, -1, -1, perf_event_open_cloexec_flag()); if (fd < 0) { pr_debug("failed opening event %llx\n", pe.config); return TEST_FAIL; } fcntl(fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC); fcntl(fd, F_SETSIG, SIGIO); fcntl(fd, F_SETOWN, getpid()); ioctl(fd, PERF_EVENT_IOC_RESET, 0); ioctl(fd, PERF_EVENT_IOC_ENABLE, 0); for (i = 0; i < EXECUTIONS; i++) test_function(); ioctl(fd, PERF_EVENT_IOC_DISABLE, 0); count = bp_count(fd); close(fd); pr_debug("count %lld, overflow %d\n", count, overflows); if (count != EXECUTIONS) { pr_debug("\tWrong number of executions %lld != %d\n", count, EXECUTIONS); fails++; } if (overflows != EXECUTIONS / THRESHOLD) { pr_debug("\tWrong number of overflows %d != %d\n", overflows, EXECUTIONS / THRESHOLD); fails++; } return fails ? TEST_FAIL : TEST_OK; } DEFINE_SUITE("Breakpoint overflow sampling", bp_signal_overflow);