memtest86plus/tests/test_helper.c
Martin Whitaker e92f488753 Improve efficiency of random number generation (discussion #8).
Use a more efficient algorithm that can be in-lined, and keep the
generator state in a local variable.
2022-03-05 20:04:32 +00:00

75 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2020-2022 Martin Whitaker.
//
// Partly derived from an extract of memtest86+ test.c:
//
// MemTest86+ V5 Specific code (GPL V2.0)
// By Samuel DEMEULEMEESTER, sdemeule@memtest.org
// http://www.canardpc.com - http://www.memtest.org
// Thanks to Passmark for calculate_chunk() and various comments !
// ----------------------------------------------------
// test.c - MemTest-86 Version 3.4
//
// Released under version 2 of the Gnu Public License.
// By Chris Brady
#include <stdint.h>
#include "cache.h"
#include "smp.h"
#include "barrier.h"
#include "config.h"
#include "display.h"
#include "test_helper.h"
//------------------------------------------------------------------------------
// Public Functions
//------------------------------------------------------------------------------
void calculate_chunk(testword_t **start, testword_t **end, int my_cpu, int segment, size_t chunk_align)
{
if (my_cpu < 0) {
my_cpu = 0;
}
// If we are only running 1 CPU then test the whole segment.
if (num_active_cpus == 1) {
*start = vm_map[segment].start;
*end = vm_map[segment].end;
} else {
uintptr_t segment_size = (vm_map[segment].end - vm_map[segment].start + 1) * sizeof(testword_t);
uintptr_t chunk_size = round_down(segment_size / num_active_cpus, chunk_align);
// Calculate chunk boundaries.
*start = (testword_t *)((uintptr_t)vm_map[segment].start + chunk_size * chunk_index[my_cpu]);
*end = (testword_t *)((uintptr_t)(*start) + chunk_size) - 1;
if (*end > vm_map[segment].end) {
*end = vm_map[segment].end;
}
}
}
void flush_caches(int my_cpu)
{
if (my_cpu >= 0) {
bool use_spin_wait = (power_save < POWER_SAVE_HIGH);
if (use_spin_wait) {
barrier_spin_wait(run_barrier);
} else {
barrier_halt_wait(run_barrier);
}
if (my_cpu == master_cpu) {
cache_flush();
}
if (use_spin_wait) {
barrier_spin_wait(run_barrier);
} else {
barrier_halt_wait(run_barrier);
}
}
}