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      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 a pinned per-task event vs an EBB - in that order. The pinned per-task
     19  * event should prevent the EBB event from being enabled.
     20  */
     21 
     22 static int setup_child_event(struct event *event, pid_t child_pid)
     23 {
     24 	event_init_named(event, 0x400FA, "PM_RUN_INST_CMPL");
     25 
     26 	event->attr.pinned = 1;
     27 
     28 	event->attr.exclude_kernel = 1;
     29 	event->attr.exclude_hv = 1;
     30 	event->attr.exclude_idle = 1;
     31 
     32 	FAIL_IF(event_open_with_pid(event, child_pid));
     33 	FAIL_IF(event_enable(event));
     34 
     35 	return 0;
     36 }
     37 
     38 int task_event_pinned_vs_ebb(void)
     39 {
     40 	union pipe read_pipe, write_pipe;
     41 	struct event event;
     42 	pid_t pid;
     43 	int rc;
     44 
     45 	SKIP_IF(!ebb_is_supported());
     46 
     47 	FAIL_IF(pipe(read_pipe.fds) == -1);
     48 	FAIL_IF(pipe(write_pipe.fds) == -1);
     49 
     50 	pid = fork();
     51 	if (pid == 0) {
     52 		/* NB order of pipes looks reversed */
     53 		exit(ebb_child(write_pipe, read_pipe));
     54 	}
     55 
     56 	/* We setup the task event first */
     57 	rc = setup_child_event(&event, pid);
     58 	if (rc) {
     59 		kill_child_and_wait(pid);
     60 		return rc;
     61 	}
     62 
     63 	/* Signal the child to install its EBB event and wait */
     64 	if (sync_with_child(read_pipe, write_pipe))
     65 		/* If it fails, wait for it to exit */
     66 		goto wait;
     67 
     68 	/* Signal the child to run */
     69 	FAIL_IF(sync_with_child(read_pipe, write_pipe));
     70 
     71 wait:
     72 	/* We expect it to fail to read the event */
     73 	FAIL_IF(wait_for_child(pid) != 2);
     74 	FAIL_IF(event_disable(&event));
     75 	FAIL_IF(event_read(&event));
     76 
     77 	event_report(&event);
     78 
     79 	FAIL_IF(event.result.value == 0);
     80 	/*
     81 	 * For reasons I don't understand enabled is usually just slightly
     82 	 * lower than running. Would be good to confirm why.
     83 	 */
     84 	FAIL_IF(event.result.enabled == 0);
     85 	FAIL_IF(event.result.running == 0);
     86 
     87 	return 0;
     88 }
     89 
     90 int main(void)
     91 {
     92 	return test_harness(task_event_pinned_vs_ebb, "task_event_pinned_vs_ebb");
     93 }
     94