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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2018 IBM Corporation.
*/
#define __SANE_USERSPACE_TYPES__
#include <sys/types.h>
#include <stdint.h>
#include <malloc.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "utils.h"
#define CACHELINE_SIZE 128
struct perf_event_read {
__u64 nr;
__u64 l1d_misses;
};
static inline __u64 load(void *addr)
{
__u64 tmp;
asm volatile("ld %0,0(%1)" : "=r"(tmp) : "b"(addr));
return tmp;
}
static void syscall_loop(char *p, unsigned long iterations,
unsigned long zero_size)
{
for (unsigned long i = 0; i < iterations; i++) {
for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
load(p + j);
getppid();
}
}
int rfi_flush_test(void)
{
char *p;
int repetitions = 10;
int fd, passes = 0, iter, rc = 0;
struct perf_event_read v;
__u64 l1d_misses_total = 0;
unsigned long iterations = 100000, zero_size = 24 * 1024;
int rfi_flush_org, rfi_flush;
SKIP_IF(geteuid() != 0);
if (read_debugfs_file("powerpc/rfi_flush", &rfi_flush_org)) {
perror("Unable to read powerpc/rfi_flush debugfs file");
SKIP_IF(1);
}
rfi_flush = rfi_flush_org;
fd = perf_event_open_counter(PERF_TYPE_RAW, /* L1d miss */ 0x400f0, -1);
FAIL_IF(fd < 0);
p = (char *)memalign(zero_size, CACHELINE_SIZE);
FAIL_IF(perf_event_enable(fd));
set_dscr(1);
iter = repetitions;
again:
FAIL_IF(perf_event_reset(fd));
syscall_loop(p, iterations, zero_size);
FAIL_IF(read(fd, &v, sizeof(v)) != sizeof(v));
/* Expect at least zero_size/CACHELINE_SIZE misses per iteration */
if (v.l1d_misses >= (iterations * zero_size / CACHELINE_SIZE) && rfi_flush)
passes++;
else if (v.l1d_misses < iterations && !rfi_flush)
passes++;
l1d_misses_total += v.l1d_misses;
while (--iter)
goto again;
if (passes < repetitions) {
printf("FAIL (L1D misses with rfi_flush=%d: %llu %c %lu) [%d/%d failures]\n",
rfi_flush, l1d_misses_total, rfi_flush ? '<' : '>',
rfi_flush ? (repetitions * iterations * zero_size / CACHELINE_SIZE) : iterations,
repetitions - passes, repetitions);
rc = 1;
} else
printf("PASS (L1D misses with rfi_flush=%d: %llu %c %lu) [%d/%d pass]\n",
rfi_flush, l1d_misses_total, rfi_flush ? '>' : '<',
rfi_flush ? (repetitions * iterations * zero_size / CACHELINE_SIZE) : iterations,
passes, repetitions);
if (rfi_flush == rfi_flush_org) {
rfi_flush = !rfi_flush_org;
if (write_debugfs_file("powerpc/rfi_flush", rfi_flush) < 0) {
perror("error writing to powerpc/rfi_flush debugfs file");
return 1;
}
iter = repetitions;
l1d_misses_total = 0;
passes = 0;
goto again;
}
perf_event_disable(fd);
close(fd);
set_dscr(0);
if (write_debugfs_file("powerpc/rfi_flush", rfi_flush_org) < 0) {
perror("unable to restore original value of powerpc/rfi_flush debugfs file");
return 1;
}
return rc;
}
int main(int argc, char *argv[])
{
return test_harness(rfi_flush_test, "rfi_flush_test");
}
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