1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright 2014, Michael Ellerman, IBM Corp. |
4 | */ |
5 | |
6 | #include <stdbool.h> |
7 | #include <stdio.h> |
8 | #include <stdlib.h> |
9 | #include <signal.h> |
10 | |
11 | #include "ebb.h" |
12 | |
13 | |
14 | /* |
15 | * Test running multiple EBB using processes at once on a single CPU. They |
16 | * should all run happily without interfering with each other. |
17 | */ |
18 | |
19 | static bool child_should_exit; |
20 | |
21 | static void sigint_handler(int signal) |
22 | { |
23 | child_should_exit = true; |
24 | } |
25 | |
26 | struct sigaction sigint_action = { |
27 | .sa_handler = sigint_handler, |
28 | }; |
29 | |
30 | static int cycles_child(void) |
31 | { |
32 | struct event event; |
33 | |
34 | if (sigaction(SIGINT, &sigint_action, NULL)) { |
35 | perror("sigaction" ); |
36 | return 1; |
37 | } |
38 | |
39 | event_init_named(e: &event, config: 0x1001e, name: "cycles" ); |
40 | event_leader_ebb_init(e: &event); |
41 | |
42 | event.attr.exclude_kernel = 1; |
43 | event.attr.exclude_hv = 1; |
44 | event.attr.exclude_idle = 1; |
45 | |
46 | FAIL_IF(event_open(e: &event)); |
47 | |
48 | ebb_enable_pmc_counting(pmc: 1); |
49 | setup_ebb_handler(standard_ebb_callee); |
50 | ebb_global_enable(); |
51 | |
52 | FAIL_IF(ebb_event_enable(e: &event)); |
53 | |
54 | mtspr(SPRN_PMC1, pmc_sample_period(value: sample_period)); |
55 | |
56 | while (!child_should_exit) { |
57 | FAIL_IF(core_busy_loop()); |
58 | FAIL_IF(ebb_check_mmcr0()); |
59 | } |
60 | |
61 | ebb_global_disable(); |
62 | ebb_freeze_pmcs(); |
63 | |
64 | dump_summary_ebb_state(); |
65 | |
66 | event_close(e: &event); |
67 | |
68 | FAIL_IF(ebb_state.stats.ebb_count == 0); |
69 | |
70 | return 0; |
71 | } |
72 | |
73 | #define NR_CHILDREN 4 |
74 | |
75 | int multi_ebb_procs(void) |
76 | { |
77 | pid_t pids[NR_CHILDREN]; |
78 | int rc, i; |
79 | |
80 | SKIP_IF(!ebb_is_supported()); |
81 | |
82 | FAIL_IF(bind_to_cpu(BIND_CPU_ANY) < 0); |
83 | |
84 | for (i = 0; i < NR_CHILDREN; i++) { |
85 | pids[i] = fork(); |
86 | if (pids[i] == 0) |
87 | exit(cycles_child()); |
88 | } |
89 | |
90 | /* Have them all run for "a while" */ |
91 | sleep(10); |
92 | |
93 | rc = 0; |
94 | for (i = 0; i < NR_CHILDREN; i++) { |
95 | /* Tell them to stop */ |
96 | kill(pids[i], SIGINT); |
97 | /* And wait */ |
98 | rc |= wait_for_child(child_pid: pids[i]); |
99 | } |
100 | |
101 | return rc; |
102 | } |
103 | |
104 | int main(void) |
105 | { |
106 | return test_harness(multi_ebb_procs, "multi_ebb_procs" ); |
107 | } |
108 | |