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_on_willing_child_test.c (1927B)

      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 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
     23static 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	dump_ebb_state();
     42
     43	FAIL_IF(ebb_state.stats.ebb_count == 0);
     44
     45	return 0;
     46}
     47
     48/* Tests we can setup an EBB on our child - if it's expecting it */
     49int ebb_on_willing_child(void)
     50{
     51	union pipe read_pipe, write_pipe;
     52	struct event event;
     53	pid_t pid;
     54
     55	SKIP_IF(!ebb_is_supported());
     56
     57	FAIL_IF(pipe(read_pipe.fds) == -1);
     58	FAIL_IF(pipe(write_pipe.fds) == -1);
     59
     60	pid = fork();
     61	if (pid == 0) {
     62		/* NB order of pipes looks reversed */
     63		exit(victim_child(write_pipe, read_pipe));
     64	}
     65
     66	/* Signal the child to setup its EBB handler */
     67	FAIL_IF(sync_with_child(read_pipe, write_pipe));
     68
     69	/* Child is running now */
     70
     71	event_init_named(&event, 0x1001e, "cycles");
     72	event_leader_ebb_init(&event);
     73
     74	event.attr.exclude_kernel = 1;
     75	event.attr.exclude_hv = 1;
     76	event.attr.exclude_idle = 1;
     77
     78	FAIL_IF(event_open_with_pid(&event, pid));
     79	FAIL_IF(ebb_event_enable(&event));
     80
     81	/* Child show now take EBBs and then exit */
     82	FAIL_IF(wait_for_child(pid));
     83
     84	event_close(&event);
     85
     86	return 0;
     87}
     88
     89int main(void)
     90{
     91	return test_harness(ebb_on_willing_child, "ebb_on_willing_child");
     92}