// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2014, Michael Ellerman, IBM Corp.
*/
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include "ebb.h"
/*
* Test running multiple EBB using processes at once on a single CPU. They
* should all run happily without interfering with each other.
*/
static bool child_should_exit;
static void sigint_handler(int signal)
{
child_should_exit = true;
}
struct sigaction sigint_action = {
.sa_handler = sigint_handler,
};
static int cycles_child(void)
{
struct event event;
if (sigaction(SIGINT, &sigint_action, NULL)) {
perror("sigaction");
return 1;
}
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(&event));
ebb_enable_pmc_counting(1);
setup_ebb_handler(standard_ebb_callee);
ebb_global_enable();
FAIL_IF(ebb_event_enable(&event));
mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
while (!child_should_exit) {
FAIL_IF(core_busy_loop());
FAIL_IF(ebb_check_mmcr0());
}
ebb_global_disable();
ebb_freeze_pmcs();
count_pmc(1, sample_period);
dump_summary_ebb_state();
event_close(&event);
FAIL_IF(ebb_state.stats.ebb_count == 0);
return 0;
}
#define NR_CHILDREN 4
int multi_ebb_procs(void)
{
pid_t pids[NR_CHILDREN];
int cpu, rc, i;
SKIP_IF(!ebb_is_supported());
cpu = pick_online_cpu();
FAIL_IF(cpu < 0);
FAIL_IF(bind_to_cpu(cpu));
for (i = 0; i < NR_CHILDREN; i++) {
pids[i] = fork();
if (pids[i] == 0)
exit(cycles_child());
}
/* Have them all run for "a while" */
sleep(10);
rc = 0;
for (i = 0; i < NR_CHILDREN; i++) {
/* Tell them to stop */
kill(pids[i], SIGINT);
/* And wait */
rc |= wait_for_child(pids[i]);
}
return rc;
}
int main(void)
{
return test_harness(multi_ebb_procs, "multi_ebb_procs");
}