cpu_event_vs_ebb_test.c (1776B)
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 cpu event vs an EBB - in that order. The EBB should force the cpu 19 * event off the PMU. 20 */ 21 22static 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 37int cpu_event_vs_ebb(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 /* We setup the cpu event first */ 60 rc = setup_cpu_event(&event, cpu); 61 if (rc) { 62 kill_child_and_wait(pid); 63 return rc; 64 } 65 66 /* Signal the child to install its EBB event and wait */ 67 if (sync_with_child(read_pipe, write_pipe)) 68 /* If it fails, wait for it to exit */ 69 goto wait; 70 71 /* Signal the child to run */ 72 FAIL_IF(sync_with_child(read_pipe, write_pipe)); 73 74wait: 75 /* We expect the child to succeed */ 76 FAIL_IF(wait_for_child(pid)); 77 78 FAIL_IF(event_disable(&event)); 79 FAIL_IF(event_read(&event)); 80 81 event_report(&event); 82 83 /* The cpu event may have run */ 84 85 return 0; 86} 87 88int main(void) 89{ 90 return test_harness(cpu_event_vs_ebb, "cpu_event_vs_ebb"); 91}