perf tests: Test breakpoint overflow signal handler counts
Adding automated test to check the exact number of breakpoint event
overflows and counts.
This test was originally done by Vince Weaver for perf_event_tests.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1362940871-24486-7-git-send-email-jolsa@redhat.com
[ committer note: s/pr_err/pr_debug/g i.e. print just OK or FAILED in non verbose mode ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/tests/bp_signal_overflow.c b/tools/perf/tests/bp_signal_overflow.c
new file mode 100644
index 0000000..fe7ed28
--- /dev/null
+++ b/tools/perf/tests/bp_signal_overflow.c
@@ -0,0 +1,126 @@
+/*
+ * Originally 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 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++;
+}
+
+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
+
+int test__bp_signal_overflow(void)
+{
+ struct perf_event_attr pe;
+ struct sigaction sa;
+ long long count;
+ int fd, i, fails = 0;
+
+ /* 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, 0);
+ 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;
+}
