cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ebb_vs_cpu_event_test.c (1806B)

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