--- /dev/null
+/*
+ * Inspired by breakpoint overflow test done by
+ * Vince Weaver <vincent.weaver@maine.edu> for perf_event_tests
+ * (git://github.com/deater/perf_event_tests)
+ */
+
+#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 "perf.h"
+
+static int fd1;
+static int fd2;
+static int overflows;
+
+__attribute__ ((noinline))
+static 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++;
+
+ if (overflows > 10) {
+ /*
+ * This should be executed only once during
+ * this test, if we are here for the 10th
+ * time, consider this the recursive issue.
+ *
+ * We can get out of here by disable events,
+ * so no new SIGIO is delivered.
+ */
+ ioctl(fd1, PERF_EVENT_IOC_DISABLE, 0);
+ ioctl(fd2, PERF_EVENT_IOC_DISABLE, 0);
+ }
+}
+
+static int bp_event(void *fn, int setup_signal)
+{
+ struct perf_event_attr pe;
+ int fd;
+
+ 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) fn;
+ pe.bp_len = sizeof(long);
+
+ pe.sample_period = 1;
+ 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, 0);
+ if (fd < 0) {
+ pr_debug("failed opening event %llx\n", pe.config);
+ return TEST_FAIL;
+ }
+
+ if (setup_signal) {
+ 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);
+
+ return fd;
+}
+
+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;
+}
+
+int test__bp_signal(void)
+{
+ struct sigaction sa;
+ long long count1, count2;
+
+ /* 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;
+ }
+
+ /*
+ * We create following events:
+ *
+ * fd1 - breakpoint event on test_function with SIGIO
+ * signal configured. We should get signal
+ * notification each time the breakpoint is hit
+ *
+ * fd2 - breakpoint event on sig_handler without SIGIO
+ * configured.
+ *
+ * Following processing should happen:
+ * - execute test_function
+ * - fd1 event breakpoint hit -> count1 == 1
+ * - SIGIO is delivered -> overflows == 1
+ * - fd2 event breakpoint hit -> count2 == 1
+ *
+ * The test case check following error conditions:
+ * - we get stuck in signal handler because of debug
+ * exception being triggered receursively due to
+ * the wrong RF EFLAG management
+ *
+ * - we never trigger the sig_handler breakpoint due
+ * to the rong RF EFLAG management
+ *
+ */
+
+ fd1 = bp_event(test_function, 1);
+ fd2 = bp_event(sig_handler, 0);
+
+ ioctl(fd1, PERF_EVENT_IOC_ENABLE, 0);
+ ioctl(fd2, PERF_EVENT_IOC_ENABLE, 0);
+
+ /*
+ * Kick off the test by trigering 'fd1'
+ * breakpoint.
+ */
+ test_function();
+
+ ioctl(fd1, PERF_EVENT_IOC_DISABLE, 0);
+ ioctl(fd2, PERF_EVENT_IOC_DISABLE, 0);
+
+ count1 = bp_count(fd1);
+ count2 = bp_count(fd2);
+
+ close(fd1);
+ close(fd2);
+
+ pr_debug("count1 %lld, count2 %lld, overflow %d\n",
+ count1, count2, overflows);
+
+ if (count1 != 1) {
+ if (count1 == 11)
+ pr_debug("failed: RF EFLAG recursion issue detected\n");
+ else
+ pr_debug("failed: wrong count for bp1%lld\n", count1);
+ }
+
+ if (overflows != 1)
+ pr_debug("failed: wrong overflow hit\n");
+
+ if (count2 != 1)
+ pr_debug("failed: wrong count for bp2\n");
+
+ return count1 == 1 && overflows == 1 && count2 == 1 ?
+ TEST_OK : TEST_FAIL;
+}
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff