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 per-task event vs an EBB - in that order. The pinned per-task
19 * event should prevent the EBB event from being enabled.
20 */
21
22static int setup_child_event(struct event *event, pid_t child_pid)
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	FAIL_IF(event_open_with_pid(event, child_pid));
33	FAIL_IF(event_enable(event));
34
35	return 0;
36}
37
38int task_event_pinned_vs_ebb(void)
39{
40	union pipe read_pipe, write_pipe;
41	struct event event;
42	pid_t pid;
43	int rc;
44
45	SKIP_IF(!ebb_is_supported());
46
47	FAIL_IF(pipe(read_pipe.fds) == -1);
48	FAIL_IF(pipe(write_pipe.fds) == -1);
49
50	pid = fork();
51	if (pid == 0) {
52		/* NB order of pipes looks reversed */
53		exit(ebb_child(write_pipe, read_pipe));
54	}
55
56	/* We setup the task event first */
57	rc = setup_child_event(&event, pid);
58	if (rc) {
59		kill_child_and_wait(pid);
60		return rc;
61	}
62
63	/* Signal the child to install its EBB event and wait */
64	if (sync_with_child(read_pipe, write_pipe))
65		/* If it fails, wait for it to exit */
66		goto wait;
67
68	/* Signal the child to run */
69	FAIL_IF(sync_with_child(read_pipe, write_pipe));
70
71wait:
72	/* We expect it to fail to read the event */
73	FAIL_IF(wait_for_child(pid) != 2);
74	FAIL_IF(event_disable(&event));
75	FAIL_IF(event_read(&event));
76
77	event_report(&event);
78
79	FAIL_IF(event.result.value == 0);
80	/*
81	 * For reasons I don't understand enabled is usually just slightly
82	 * lower than running. Would be good to confirm why.
83	 */
84	FAIL_IF(event.result.enabled == 0);
85	FAIL_IF(event.result.running == 0);
86
87	return 0;
88}
89
90int main(void)
91{
92	return test_harness(task_event_pinned_vs_ebb, "task_event_pinned_vs_ebb");
93}
94