forked from luck/tmp_suning_uos_patched
8e50d384cc
The tail position of the event buffer should only be modified after actually use that event. If not the event buffer could be invalid before use, and segment fault occurs when invoking perf top -G. Signed-off-by: Zhouyi Zhou <yizhouzhou@ict.ac.cn> Cc: David Ahern <dsahern@gmail.com> Cc: Zhouyi Zhou <yizhouzhou@ict.ac.cn> Link: http://lkml.kernel.org/r/1382600613-32177-1-git-send-email-zhouzhouyi@gmail.com [ Simplified the logic using exit gotos and renamed write_tail method to mmap_consume ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
124 lines
2.7 KiB
C
124 lines
2.7 KiB
C
#include "evlist.h"
|
|
#include "evsel.h"
|
|
#include "thread_map.h"
|
|
#include "cpumap.h"
|
|
#include "tests.h"
|
|
|
|
#include <signal.h>
|
|
|
|
static int exited;
|
|
static int nr_exit;
|
|
|
|
static void sig_handler(int sig)
|
|
{
|
|
exited = 1;
|
|
|
|
if (sig == SIGUSR1)
|
|
nr_exit = -1;
|
|
}
|
|
|
|
/*
|
|
* This test will start a workload that does nothing then it checks
|
|
* if the number of exit event reported by the kernel is 1 or not
|
|
* in order to check the kernel returns correct number of event.
|
|
*/
|
|
int test__task_exit(void)
|
|
{
|
|
int err = -1;
|
|
union perf_event *event;
|
|
struct perf_evsel *evsel;
|
|
struct perf_evlist *evlist;
|
|
struct perf_target target = {
|
|
.uid = UINT_MAX,
|
|
.uses_mmap = true,
|
|
};
|
|
const char *argv[] = { "true", NULL };
|
|
|
|
signal(SIGCHLD, sig_handler);
|
|
signal(SIGUSR1, sig_handler);
|
|
|
|
evlist = perf_evlist__new();
|
|
if (evlist == NULL) {
|
|
pr_debug("perf_evlist__new\n");
|
|
return -1;
|
|
}
|
|
/*
|
|
* We need at least one evsel in the evlist, use the default
|
|
* one: "cycles".
|
|
*/
|
|
err = perf_evlist__add_default(evlist);
|
|
if (err < 0) {
|
|
pr_debug("Not enough memory to create evsel\n");
|
|
goto out_free_evlist;
|
|
}
|
|
|
|
/*
|
|
* Create maps of threads and cpus to monitor. In this case
|
|
* we start with all threads and cpus (-1, -1) but then in
|
|
* perf_evlist__prepare_workload we'll fill in the only thread
|
|
* we're monitoring, the one forked there.
|
|
*/
|
|
evlist->cpus = cpu_map__dummy_new();
|
|
evlist->threads = thread_map__new_by_tid(-1);
|
|
if (!evlist->cpus || !evlist->threads) {
|
|
err = -ENOMEM;
|
|
pr_debug("Not enough memory to create thread/cpu maps\n");
|
|
goto out_delete_maps;
|
|
}
|
|
|
|
err = perf_evlist__prepare_workload(evlist, &target, argv, false, true);
|
|
if (err < 0) {
|
|
pr_debug("Couldn't run the workload!\n");
|
|
goto out_delete_maps;
|
|
}
|
|
|
|
evsel = perf_evlist__first(evlist);
|
|
evsel->attr.task = 1;
|
|
evsel->attr.sample_freq = 0;
|
|
evsel->attr.inherit = 0;
|
|
evsel->attr.watermark = 0;
|
|
evsel->attr.wakeup_events = 1;
|
|
evsel->attr.exclude_kernel = 1;
|
|
|
|
err = perf_evlist__open(evlist);
|
|
if (err < 0) {
|
|
pr_debug("Couldn't open the evlist: %s\n", strerror(-err));
|
|
goto out_delete_maps;
|
|
}
|
|
|
|
if (perf_evlist__mmap(evlist, 128, true) < 0) {
|
|
pr_debug("failed to mmap events: %d (%s)\n", errno,
|
|
strerror(errno));
|
|
goto out_close_evlist;
|
|
}
|
|
|
|
perf_evlist__start_workload(evlist);
|
|
|
|
retry:
|
|
while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
|
|
if (event->header.type == PERF_RECORD_EXIT)
|
|
nr_exit++;
|
|
|
|
perf_evlist__mmap_consume(evlist, 0);
|
|
}
|
|
|
|
if (!exited || !nr_exit) {
|
|
poll(evlist->pollfd, evlist->nr_fds, -1);
|
|
goto retry;
|
|
}
|
|
|
|
if (nr_exit != 1) {
|
|
pr_debug("received %d EXIT records\n", nr_exit);
|
|
err = -1;
|
|
}
|
|
|
|
perf_evlist__munmap(evlist);
|
|
out_close_evlist:
|
|
perf_evlist__close(evlist);
|
|
out_delete_maps:
|
|
perf_evlist__delete_maps(evlist);
|
|
out_free_evlist:
|
|
perf_evlist__delete(evlist);
|
|
return err;
|
|
}
|