1 /* 2 * Copyright 2014, Michael Ellerman, IBM Corp. 3 * Licensed under GPLv2. 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 we can setup an EBB on our child. The child expects this and enables 19 * EBBs, which are then delivered to the child, even though the event is 20 * created by the parent. 21 */ 22 23 static int victim_child(union pipe read_pipe, union pipe write_pipe) 24 { 25 FAIL_IF(wait_for_parent(read_pipe)); 26 27 /* Setup our EBB handler, before the EBB event is created */ 28 ebb_enable_pmc_counting(1); 29 setup_ebb_handler(standard_ebb_callee); 30 ebb_global_enable(); 31 32 FAIL_IF(notify_parent(write_pipe)); 33 34 while (ebb_state.stats.ebb_count < 20) { 35 FAIL_IF(core_busy_loop()); 36 } 37 38 ebb_global_disable(); 39 ebb_freeze_pmcs(); 40 41 count_pmc(1, sample_period); 42 43 dump_ebb_state(); 44 45 FAIL_IF(ebb_state.stats.ebb_count == 0); 46 47 return 0; 48 } 49 50 /* Tests we can setup an EBB on our child - if it's expecting it */ 51 int ebb_on_willing_child(void) 52 { 53 union pipe read_pipe, write_pipe; 54 struct event event; 55 pid_t pid; 56 57 SKIP_IF(!ebb_is_supported()); 58 59 FAIL_IF(pipe(read_pipe.fds) == -1); 60 FAIL_IF(pipe(write_pipe.fds) == -1); 61 62 pid = fork(); 63 if (pid == 0) { 64 /* NB order of pipes looks reversed */ 65 exit(victim_child(write_pipe, read_pipe)); 66 } 67 68 /* Signal the child to setup its EBB handler */ 69 FAIL_IF(sync_with_child(read_pipe, write_pipe)); 70 71 /* Child is running now */ 72 73 event_init_named(&event, 0x1001e, "cycles"); 74 event_leader_ebb_init(&event); 75 76 event.attr.exclude_kernel = 1; 77 event.attr.exclude_hv = 1; 78 event.attr.exclude_idle = 1; 79 80 FAIL_IF(event_open_with_pid(&event, pid)); 81 FAIL_IF(ebb_event_enable(&event)); 82 83 /* Child show now take EBBs and then exit */ 84 FAIL_IF(wait_for_child(pid)); 85 86 event_close(&event); 87 88 return 0; 89 } 90 91 int main(void) 92 { 93 return test_harness(ebb_on_willing_child, "ebb_on_willing_child"); 94 } 95
