summaryrefslogtreecommitdiff
path: root/src/memtest.c
blob: a455430f5df52c3a2a2c39b9b6354114f9e0f42a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
/*
 * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *   * Neither the name of Redis nor the names of its contributors may be used
 *     to endorse or promote products derived from this software without
 *     specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <limits.h>
#include <errno.h>
#include <termios.h>
#include <sys/ioctl.h>
#if defined(__sun)
#include <stropts.h>
#endif
#include "config.h"

#if (ULONG_MAX == 4294967295UL)
#define MEMTEST_32BIT
#elif (ULONG_MAX == 18446744073709551615ULL)
#define MEMTEST_64BIT
#else
#error "ULONG_MAX value not supported."
#endif

#ifdef MEMTEST_32BIT
#define ULONG_ONEZERO 0xaaaaaaaaUL
#define ULONG_ZEROONE 0x55555555UL
#else
#define ULONG_ONEZERO 0xaaaaaaaaaaaaaaaaUL
#define ULONG_ZEROONE 0x5555555555555555UL
#endif

static struct winsize ws;
size_t progress_printed; /* Printed chars in screen-wide progress bar. */
size_t progress_full; /* How many chars to write to fill the progress bar. */

void memtest_progress_start(char *title, int pass) {
    int j;

    printf("\x1b[H\x1b[2J");    /* Cursor home, clear screen. */
    /* Fill with dots. */
    for (j = 0; j < ws.ws_col*(ws.ws_row-2); j++) printf(".");
    printf("Please keep the test running several minutes per GB of memory.\n");
    printf("Also check http://www.memtest86.com/ and http://pyropus.ca/software/memtester/");
    printf("\x1b[H\x1b[2K");          /* Cursor home, clear current line.  */
    printf("%s [%d]\n", title, pass); /* Print title. */
    progress_printed = 0;
    progress_full = ws.ws_col*(ws.ws_row-3);
    fflush(stdout);
}

void memtest_progress_end(void) {
    printf("\x1b[H\x1b[2J");    /* Cursor home, clear screen. */
}

void memtest_progress_step(size_t curr, size_t size, char c) {
    size_t chars = ((unsigned long long)curr*progress_full)/size, j;

    for (j = 0; j < chars-progress_printed; j++) printf("%c",c);
    progress_printed = chars;
    fflush(stdout);
}

/* Test that addressing is fine. Every location is populated with its own
 * address, and finally verified. This test is very fast but may detect
 * ASAP big issues with the memory subsystem. */
int memtest_addressing(unsigned long *l, size_t bytes, int interactive) {
    unsigned long words = bytes/sizeof(unsigned long);
    unsigned long j, *p;

    /* Fill */
    p = l;
    for (j = 0; j < words; j++) {
        *p = (unsigned long)p;
        p++;
        if ((j & 0xffff) == 0 && interactive)
            memtest_progress_step(j,words*2,'A');
    }
    /* Test */
    p = l;
    for (j = 0; j < words; j++) {
        if (*p != (unsigned long)p) {
            if (interactive) {
                printf("\n*** MEMORY ADDRESSING ERROR: %p contains %lu\n",
                    (void*) p, *p);
                exit(1);
            }
            return 1;
        }
        p++;
        if ((j & 0xffff) == 0 && interactive)
            memtest_progress_step(j+words,words*2,'A');
    }
    return 0;
}

/* Fill words stepping a single page at every write, so we continue to
 * touch all the pages in the smallest amount of time reducing the
 * effectiveness of caches, and making it hard for the OS to transfer
 * pages on the swap.
 *
 * In this test we can't call rand() since the system may be completely
 * unable to handle library calls, so we have to resort to our own
 * PRNG that only uses local state. We use an xorshift* PRNG. */
#define xorshift64star_next() do { \
        rseed ^= rseed >> 12; \
        rseed ^= rseed << 25; \
        rseed ^= rseed >> 27; \
        rout = rseed * UINT64_C(2685821657736338717); \
} while(0)

void memtest_fill_random(unsigned long *l, size_t bytes, int interactive) {
    unsigned long step = 4096/sizeof(unsigned long);
    unsigned long words = bytes/sizeof(unsigned long)/2;
    unsigned long iwords = words/step;  /* words per iteration */
    unsigned long off, w, *l1, *l2;
    uint64_t rseed = UINT64_C(0xd13133de9afdb566); /* Just a random seed. */
    uint64_t rout = 0;

    assert((bytes & 4095) == 0);
    for (off = 0; off < step; off++) {
        l1 = l+off;
        l2 = l1+words;
        for (w = 0; w < iwords; w++) {
            xorshift64star_next();
            *l1 = *l2 = (unsigned long) rout;
            l1 += step;
            l2 += step;
            if ((w & 0xffff) == 0 && interactive)
                memtest_progress_step(w+iwords*off,words,'R');
        }
    }
}

/* Like memtest_fill_random() but uses the two specified values to fill
 * memory, in an alternated way (v1|v2|v1|v2|...) */
void memtest_fill_value(unsigned long *l, size_t bytes, unsigned long v1,
                        unsigned long v2, char sym, int interactive)
{
    unsigned long step = 4096/sizeof(unsigned long);
    unsigned long words = bytes/sizeof(unsigned long)/2;
    unsigned long iwords = words/step;  /* words per iteration */
    unsigned long off, w, *l1, *l2, v;

    assert((bytes & 4095) == 0);
    for (off = 0; off < step; off++) {
        l1 = l+off;
        l2 = l1+words;
        v = (off & 1) ? v2 : v1;
        for (w = 0; w < iwords; w++) {
#ifdef MEMTEST_32BIT
            *l1 = *l2 = ((unsigned long)     v) |
                        (((unsigned long)    v) << 16);
#else
            *l1 = *l2 = ((unsigned long)     v) |
                        (((unsigned long)    v) << 16) |
                        (((unsigned long)    v) << 32) |
                        (((unsigned long)    v) << 48);
#endif
            l1 += step;
            l2 += step;
            if ((w & 0xffff) == 0 && interactive)
                memtest_progress_step(w+iwords*off,words,sym);
        }
    }
}

int memtest_compare(unsigned long *l, size_t bytes, int interactive) {
    unsigned long words = bytes/sizeof(unsigned long)/2;
    unsigned long w, *l1, *l2;

    assert((bytes & 4095) == 0);
    l1 = l;
    l2 = l1+words;
    for (w = 0; w < words; w++) {
        if (*l1 != *l2) {
            if (interactive) {
                printf("\n*** MEMORY ERROR DETECTED: %p != %p (%lu vs %lu)\n",
                    (void*)l1, (void*)l2, *l1, *l2);
                exit(1);
            }
            return 1;
        }
        l1 ++;
        l2 ++;
        if ((w & 0xffff) == 0 && interactive)
            memtest_progress_step(w,words,'=');
    }
    return 0;
}

int memtest_compare_times(unsigned long *m, size_t bytes, int pass, int times,
                          int interactive)
{
    int j;
    int errors = 0;

    for (j = 0; j < times; j++) {
        if (interactive) memtest_progress_start("Compare",pass);
        errors += memtest_compare(m,bytes,interactive);
        if (interactive) memtest_progress_end();
    }
    return errors;
}

/* Test the specified memory. The number of bytes must be multiple of 4096.
 * If interactive is true the program exists with an error and prints
 * ASCII arts to show progresses. Instead when interactive is 0, it can
 * be used as an API call, and returns 1 if memory errors were found or
 * 0 if there were no errors detected. */
int memtest_test(unsigned long *m, size_t bytes, int passes, int interactive) {
    int pass = 0;
    int errors = 0;

    while (pass != passes) {
        pass++;

        if (interactive) memtest_progress_start("Addressing test",pass);
        errors += memtest_addressing(m,bytes,interactive);
        if (interactive) memtest_progress_end();

        if (interactive) memtest_progress_start("Random fill",pass);
        memtest_fill_random(m,bytes,interactive);
        if (interactive) memtest_progress_end();
        errors += memtest_compare_times(m,bytes,pass,4,interactive);

        if (interactive) memtest_progress_start("Solid fill",pass);
        memtest_fill_value(m,bytes,0,(unsigned long)-1,'S',interactive);
        if (interactive) memtest_progress_end();
        errors += memtest_compare_times(m,bytes,pass,4,interactive);

        if (interactive) memtest_progress_start("Checkerboard fill",pass);
        memtest_fill_value(m,bytes,ULONG_ONEZERO,ULONG_ZEROONE,'C',interactive);
        if (interactive) memtest_progress_end();
        errors += memtest_compare_times(m,bytes,pass,4,interactive);
    }
    return errors;
}

/* A version of memtest_test() that tests memory in small pieces
 * in order to restore the memory content at exit.
 *
 * One problem we have with this approach, is that the cache can avoid
 * real memory accesses, and we can't test big chunks of memory at the
 * same time, because we need to backup them on the stack (the allocator
 * may not be usable or we may be already in an out of memory condition).
 * So what we do is to try to trash the cache with useless memory accesses
 * between the fill and compare cycles. */
#define MEMTEST_BACKUP_WORDS (1024*(1024/sizeof(long)))
/* Random accesses of MEMTEST_DECACHE_SIZE are performed at the start and
 * end of the region between fill and compare cycles in order to trash
 * the cache. */
#define MEMTEST_DECACHE_SIZE (1024*8)
int memtest_preserving_test(unsigned long *m, size_t bytes, int passes) {
    unsigned long backup[MEMTEST_BACKUP_WORDS];
    unsigned long *p = m;
    unsigned long *end = (unsigned long*) (((unsigned char*)m)+(bytes-MEMTEST_DECACHE_SIZE));
    size_t left = bytes;
    int errors = 0;

    if (bytes & 4095) return 0; /* Can't test across 4k page boundaries. */
    if (bytes < 4096*2) return 0; /* Can't test a single page. */

    while(left) {
        /* If we have to test a single final page, go back a single page
         * so that we can test two pages, since the code can't test a single
         * page but at least two. */
        if (left == 4096) {
            left += 4096;
            p -= 4096/sizeof(unsigned long);
        }

        int pass = 0;
        size_t len = (left > sizeof(backup)) ? sizeof(backup) : left;

        /* Always test an even number of pages. */
        if (len/4096 % 2) len -= 4096;

        memcpy(backup,p,len); /* Backup. */
        while(pass != passes) {
            pass++;
            errors += memtest_addressing(p,len,0);
            memtest_fill_random(p,len,0);
            if (bytes >= MEMTEST_DECACHE_SIZE) {
                memtest_compare_times(m,MEMTEST_DECACHE_SIZE,pass,1,0);
                memtest_compare_times(end,MEMTEST_DECACHE_SIZE,pass,1,0);
            }
            errors += memtest_compare_times(p,len,pass,4,0);
            memtest_fill_value(p,len,0,(unsigned long)-1,'S',0);
            if (bytes >= MEMTEST_DECACHE_SIZE) {
                memtest_compare_times(m,MEMTEST_DECACHE_SIZE,pass,1,0);
                memtest_compare_times(end,MEMTEST_DECACHE_SIZE,pass,1,0);
            }
            errors += memtest_compare_times(p,len,pass,4,0);
            memtest_fill_value(p,len,ULONG_ONEZERO,ULONG_ZEROONE,'C',0);
            if (bytes >= MEMTEST_DECACHE_SIZE) {
                memtest_compare_times(m,MEMTEST_DECACHE_SIZE,pass,1,0);
                memtest_compare_times(end,MEMTEST_DECACHE_SIZE,pass,1,0);
            }
            errors += memtest_compare_times(p,len,pass,4,0);
        }
        memcpy(p,backup,len); /* Restore. */
        left -= len;
        p += len/sizeof(unsigned long);
    }
    return errors;
}

/* Perform an interactive test allocating the specified number of megabytes. */
void memtest_alloc_and_test(size_t megabytes, int passes) {
    size_t bytes = megabytes*1024*1024;
    unsigned long *m = malloc(bytes);

    if (m == NULL) {
        fprintf(stderr,"Unable to allocate %zu megabytes: %s",
            megabytes, strerror(errno));
        exit(1);
    }
    memtest_test(m,bytes,passes,1);
    free(m);
}

void memtest(size_t megabytes, int passes) {
    if (ioctl(1, TIOCGWINSZ, &ws) == -1) {
        ws.ws_col = 80;
        ws.ws_row = 20;
    }
    memtest_alloc_and_test(megabytes,passes);
    printf("\nYour memory passed this test.\n");
    printf("Please if you are still in doubt use the following two tools:\n");
    printf("1) memtest86: http://www.memtest86.com/\n");
    printf("2) memtester: http://pyropus.ca/software/memtester/\n");
    exit(0);
}