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 | |
22 | static int setup_cpu_event(struct event *event, int cpu) |
23 | { |
24 | event_init_named(e: event, config: 0x400FA, name: "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(level: 1)); |
31 | FAIL_IF(event_open_with_cpu(e: event, cpu)); |
32 | FAIL_IF(event_enable(e: event)); |
33 | |
34 | return 0; |
35 | } |
36 | |
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 = bind_to_cpu(BIND_CPU_ANY); |
47 | FAIL_IF(cpu < 0); |
48 | |
49 | FAIL_IF(pipe(read_pipe.fds) == -1); |
50 | FAIL_IF(pipe(write_pipe.fds) == -1); |
51 | |
52 | pid = fork(); |
53 | if (pid == 0) { |
54 | /* NB order of pipes looks reversed */ |
55 | exit(ebb_child(read_pipe: write_pipe, write_pipe: read_pipe)); |
56 | } |
57 | |
58 | /* Signal the child to install its EBB event and wait */ |
59 | FAIL_IF(sync_with_child(read_pipe, write_pipe)); |
60 | |
61 | /* Now try to install our CPU event */ |
62 | rc = setup_cpu_event(event: &event, cpu); |
63 | if (rc) { |
64 | kill_child_and_wait(child_pid: pid); |
65 | return rc; |
66 | } |
67 | |
68 | /* Signal the child to run */ |
69 | FAIL_IF(sync_with_child(read_pipe, write_pipe)); |
70 | |
71 | /* .. and wait for it to complete */ |
72 | FAIL_IF(wait_for_child(child_pid: pid)); |
73 | FAIL_IF(event_disable(e: &event)); |
74 | FAIL_IF(event_read(e: &event)); |
75 | |
76 | event_report(e: &event); |
77 | |
78 | /* The cpu event may have run, but we don't expect 100% */ |
79 | FAIL_IF(event.result.enabled >= event.result.running); |
80 | |
81 | return 0; |
82 | } |
83 | |
84 | int main(void) |
85 | { |
86 | return test_harness(ebb_vs_cpu_event, "ebb_vs_cpu_event" ); |
87 | } |
88 | |