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(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 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 85 int main(void) 86 { 87 return test_harness(ebb_vs_cpu_event, "ebb_vs_cpu_event"); 88 } 89