- 根目录:
- tools
- testing
- selftests
- powerpc
- pmu
- ebb
- ebb_on_willing_child_test.c
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
* Licensed under GPLv2.
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "ebb.h"
/*
* Tests we can setup an EBB on our child. The child expects this and enables
* EBBs, which are then delivered to the child, even though the event is
* created by the parent.
*/
static int victim_child(union pipe read_pipe, union pipe write_pipe)
{
FAIL_IF(wait_for_parent(read_pipe));
/* Setup our EBB handler, before the EBB event is created */
ebb_enable_pmc_counting(1);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(notify_parent(write_pipe));
while (ebb_state.stats.ebb_count < 20) {
FAIL_IF(core_busy_loop());
}
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_ebb_state();
FAIL_IF(ebb_state.stats.ebb_count == 0);
return 0;
}
/* Tests we can setup an EBB on our child - if it's expecting it */
int ebb_on_willing_child(void)
{
union pipe read_pipe, write_pipe;
struct event event;
pid_t pid;
FAIL_IF(pipe(read_pipe.fds) == -1);
FAIL_IF(pipe(write_pipe.fds) == -1);
pid = fork();
if (pid == 0) {
/* NB order of pipes looks reversed */
exit(victim_child(write_pipe, read_pipe));
}
/* Signal the child to setup its EBB handler */
FAIL_IF(sync_with_child(read_pipe, write_pipe));
/* Child is running now */
event_init_named(&event, 0x1001e, "cycles");
event_leader_ebb_init(&event);
event.attr.exclude_kernel = 1;
event.attr.exclude_hv = 1;
event.attr.exclude_idle = 1;
FAIL_IF(event_open_with_pid(&event, pid));
FAIL_IF(ebb_event_enable(&event));
/* Child show now take EBBs and then exit */
FAIL_IF(wait_for_child(pid));
event_close(&event);
return 0;
}
int main(void)
{
return test_harness(ebb_on_willing_child, "ebb_on_willing_child");
}