| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright 2014, Michael Ellerman, IBM Corp. |
| */ |
| |
| #include <signal.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <stdbool.h> |
| #include <sys/types.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| |
| #include "ebb.h" |
| |
| |
| /* |
| * Tests we can setup an EBB on our child. The child expects this and enables |
| * EBBs, which are then delivered to the child, even though the event is |
| * created by the parent. |
| */ |
| |
| static int victim_child(union pipe read_pipe, union pipe write_pipe) |
| { |
| FAIL_IF(wait_for_parent(read_pipe)); |
| |
| /* Setup our EBB handler, before the EBB event is created */ |
| ebb_enable_pmc_counting(1); |
| setup_ebb_handler(standard_ebb_callee); |
| ebb_global_enable(); |
| |
| FAIL_IF(notify_parent(write_pipe)); |
| |
| while (ebb_state.stats.ebb_count < 20) { |
| FAIL_IF(core_busy_loop()); |
| } |
| |
| ebb_global_disable(); |
| ebb_freeze_pmcs(); |
| |
| dump_ebb_state(); |
| |
| FAIL_IF(ebb_state.stats.ebb_count == 0); |
| |
| return 0; |
| } |
| |
| /* Tests we can setup an EBB on our child - if it's expecting it */ |
| int ebb_on_willing_child(void) |
| { |
| union pipe read_pipe, write_pipe; |
| struct event event; |
| pid_t pid; |
| |
| SKIP_IF(!ebb_is_supported()); |
| |
| FAIL_IF(pipe(read_pipe.fds) == -1); |
| FAIL_IF(pipe(write_pipe.fds) == -1); |
| |
| pid = fork(); |
| if (pid == 0) { |
| /* NB order of pipes looks reversed */ |
| exit(victim_child(write_pipe, read_pipe)); |
| } |
| |
| /* Signal the child to setup its EBB handler */ |
| FAIL_IF(sync_with_child(read_pipe, write_pipe)); |
| |
| /* Child is running now */ |
| |
| event_init_named(&event, 0x1001e, "cycles"); |
| event_leader_ebb_init(&event); |
| |
| event.attr.exclude_kernel = 1; |
| event.attr.exclude_hv = 1; |
| event.attr.exclude_idle = 1; |
| |
| FAIL_IF(event_open_with_pid(&event, pid)); |
| FAIL_IF(ebb_event_enable(&event)); |
| |
| /* Child show now take EBBs and then exit */ |
| FAIL_IF(wait_for_child(pid)); |
| |
| event_close(&event); |
| |
| return 0; |
| } |
| |
| int main(void) |
| { |
| return test_harness(ebb_on_willing_child, "ebb_on_willing_child"); |
| } |