LXR linux/tools/testing/selftests/powerpc/pmu/ebb/cpu_event_pinned_vs_ebb

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright 2014, Michael Ellerman, IBM Corp.
   4 */
   5
   6#include <signal.h>
   7#include <stdio.h>
   8#include <stdlib.h>
   9#include <stdbool.h>
  10#include <sys/types.h>
  11#include <sys/wait.h>
  12#include <unistd.h>
  13
  14#include "ebb.h"
  15
  16
  17/*
  18 * Tests a pinned cpu event vs an EBB - in that order. The pinned cpu event
  19 * should remain and the EBB event should fail to enable.
  20 */
  21
  22static int setup_cpu_event(struct event *event, int cpu)
  23{
  24        event_init_named(event, 0x400FA, "PM_RUN_INST_CMPL");
  25
  26        event->attr.pinned = 1;
  27
  28        event->attr.exclude_kernel = 1;
  29        event->attr.exclude_hv = 1;
  30        event->attr.exclude_idle = 1;
  31
  32        SKIP_IF(require_paranoia_below(1));
  33        FAIL_IF(event_open_with_cpu(event, cpu));
  34        FAIL_IF(event_enable(event));
  35
  36        return 0;
  37}
  38
  39int cpu_event_pinned_vs_ebb(void)
  40{
  41        union pipe read_pipe, write_pipe;
  42        struct event event;
  43        int cpu, rc;
  44        pid_t pid;
  45
  46        SKIP_IF(!ebb_is_supported());
  47
  48        cpu = pick_online_cpu();
  49        FAIL_IF(cpu < 0);
  50        FAIL_IF(bind_to_cpu(cpu));
  51
  52        FAIL_IF(pipe(read_pipe.fds) == -1);
  53        FAIL_IF(pipe(write_pipe.fds) == -1);
  54
  55        pid = fork();
  56        if (pid == 0) {
  57                /* NB order of pipes looks reversed */
  58                exit(ebb_child(write_pipe, read_pipe));
  59        }
  60
  61        /* We setup the cpu event first */
  62        rc = setup_cpu_event(&event, cpu);
  63        if (rc) {
  64                kill_child_and_wait(pid);
  65                return rc;
  66        }
  67
  68        /* Signal the child to install its EBB event and wait */
  69        if (sync_with_child(read_pipe, write_pipe))
  70                /* If it fails, wait for it to exit */
  71                goto wait;
  72
  73        /* Signal the child to run */
  74        FAIL_IF(sync_with_child(read_pipe, write_pipe));
  75
  76wait:
  77        /* We expect it to fail to read the event */
  78        FAIL_IF(wait_for_child(pid) != 2);
  79
  80        FAIL_IF(event_disable(&event));
  81        FAIL_IF(event_read(&event));
  82
  83        event_report(&event);
  84
  85        /* The cpu event should have run */
  86        FAIL_IF(event.result.value == 0);
  87        FAIL_IF(event.result.enabled != event.result.running);
  88
  89        return 0;
  90}
  91
  92int main(void)
  93{
  94        return test_harness(cpu_event_pinned_vs_ebb, "cpu_event_pinned_vs_ebb");
  95}
  96