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 an EBB vs a cpu event - in that order. The EBB should force the cpu
19 * event off the PMU.
20 */
21
setup_cpu_event(struct event * event,int cpu)22 static int setup_cpu_event(struct event *event, int cpu)
23 {
24 event_init_named(event, 0x400FA, "PM_RUN_INST_CMPL");
25
26 event->attr.exclude_kernel = 1;
27 event->attr.exclude_hv = 1;
28 event->attr.exclude_idle = 1;
29
30 SKIP_IF(require_paranoia_below(1));
31 FAIL_IF(event_open_with_cpu(event, cpu));
32 FAIL_IF(event_enable(event));
33
34 return 0;
35 }
36
ebb_vs_cpu_event(void)37 int ebb_vs_cpu_event(void)
38 {
39 union pipe read_pipe, write_pipe;
40 struct event event;
41 int cpu, rc;
42 pid_t pid;
43
44 SKIP_IF(!ebb_is_supported());
45
46 cpu = pick_online_cpu();
47 FAIL_IF(cpu < 0);
48 FAIL_IF(bind_to_cpu(cpu));
49
50 FAIL_IF(pipe(read_pipe.fds) == -1);
51 FAIL_IF(pipe(write_pipe.fds) == -1);
52
53 pid = fork();
54 if (pid == 0) {
55 /* NB order of pipes looks reversed */
56 exit(ebb_child(write_pipe, read_pipe));
57 }
58
59 /* Signal the child to install its EBB event and wait */
60 FAIL_IF(sync_with_child(read_pipe, write_pipe));
61
62 /* Now try to install our CPU event */
63 rc = setup_cpu_event(&event, cpu);
64 if (rc) {
65 kill_child_and_wait(pid);
66 return rc;
67 }
68
69 /* Signal the child to run */
70 FAIL_IF(sync_with_child(read_pipe, write_pipe));
71
72 /* .. and wait for it to complete */
73 FAIL_IF(wait_for_child(pid));
74 FAIL_IF(event_disable(&event));
75 FAIL_IF(event_read(&event));
76
77 event_report(&event);
78
79 /* The cpu event may have run, but we don't expect 100% */
80 FAIL_IF(event.result.enabled >= event.result.running);
81
82 return 0;
83 }
84
main(void)85 int main(void)
86 {
87 return test_harness(ebb_vs_cpu_event, "ebb_vs_cpu_event");
88 }
89
