remarkable-linux/tools/perf/tests/bp_signal_overflow.c
Yann Droneaud 57480d2cd9 perf tools: Enable close-on-exec flag on perf file descriptor
In commit a21b0b354d ('perf: Introduce a flag to enable
close-on-exec in perf_event_open()'), flag PERF_FLAG_FD_CLOEXEC
was added to perf_event_open(2) syscall to allows userspace
to atomically enable close-on-exec behavor when creating
the file descriptor.

This patch makes perf tools use the new flag if supported
by the kernel, so that the event file descriptors got
automatically closed if perf tool exec a sub-command.

Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/1404160127-7475-1-git-send-email-ydroneaud@opteya.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
2014-07-18 09:09:34 +02:00

135 lines
2.7 KiB
C

/*
* 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 "perf.h"
#include "cloexec.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,
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;
}