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 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 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 = 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(write_pipe, read_pipe)); 56 } 57 58 /* We setup the cpu event first */ 59 rc = setup_cpu_event(&event, cpu); 60 if (rc) { 61 kill_child_and_wait(pid); 62 return rc; 63 } 64 65 /* Signal the child to install its EBB event and wait */ 66 if (sync_with_child(read_pipe, write_pipe)) 67 /* If it fails, wait for it to exit */ 68 goto wait; 69 70 /* Signal the child to run */ 71 FAIL_IF(sync_with_child(read_pipe, write_pipe)); 72 73 wait: 74 /* We expect the child to succeed */ 75 FAIL_IF(wait_for_child(pid)); 76 77 FAIL_IF(event_disable(&event)); 78 FAIL_IF(event_read(&event)); 79 80 event_report(&event); 81 82 /* The cpu event may have run */ 83 84 return 0; 85 } 86 87 int main(void) 88 { 89 return test_harness(cpu_event_vs_ebb, "cpu_event_vs_ebb"); 90 } 91