varnish-cache/bin/varnishd/cache/cache_shmlog.c
0
/*-
1
 * Copyright (c) 2006 Verdens Gang AS
2
 * Copyright (c) 2006-2015 Varnish Software AS
3
 * All rights reserved.
4
 *
5
 * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
6
 *
7
 * SPDX-License-Identifier: BSD-2-Clause
8
 *
9
 * Redistribution and use in source and binary forms, with or without
10
 * modification, are permitted provided that the following conditions
11
 * are met:
12
 * 1. Redistributions of source code must retain the above copyright
13
 *    notice, this list of conditions and the following disclaimer.
14
 * 2. Redistributions in binary form must reproduce the above copyright
15
 *    notice, this list of conditions and the following disclaimer in the
16
 *    documentation and/or other materials provided with the distribution.
17
 *
18
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21
 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
22
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28
 * SUCH DAMAGE.
29
 */
30
31
#include "config.h"
32
33
#include "cache_varnishd.h"
34
35
#include <stdio.h>
36
#include <stdlib.h>
37
38
#include "vgz.h"
39
#include "vsl_priv.h"
40
#include "vmb.h"
41
42
#include "common/heritage.h"
43
#include "common/vsmw.h"
44
45
/* ------------------------------------------------------------
46
 * strands helpers - move elsewhere?
47
 */
48
49
static unsigned
50 144406
strands_len(const struct strands *s)
51
{
52 144406
        unsigned r = 0;
53
        int i;
54
55 288993
        for (i = 0; i < s->n; i++) {
56 144587
                if (s->p[i] == NULL || *s->p[i] == '\0')
57 13828
                        continue;
58 130759
                r += strlen(s->p[i]);
59 130759
        }
60
61 144406
        return (r);
62
}
63
64
/*
65
 * like VRT_Strands(), but truncating instead of failing for end of buffer
66
 *
67
 * returns number of bytes including NUL
68
 */
69
static unsigned
70 144968
strands_cat(char *buf, unsigned bufl, const struct strands *s)
71
{
72 144968
        unsigned l = 0, ll;
73
        int i;
74
75
        /* NUL-terminated */
76 144968
        assert(bufl > 0);
77 144968
        bufl--;
78
79 276576
        for (i = 0; i < s->n && bufl > 0; i++) {
80 131608
                if (s->p[i] == NULL || *s->p[i] == '\0')
81 6
                        continue;
82 131602
                ll = vmin_t(unsigned, strlen(s->p[i]), bufl);
83 131602
                memcpy(buf, s->p[i], ll);
84 131602
                l += ll;
85 131602
                buf += ll;
86 131602
                bufl -= ll;
87 131602
        }
88 144968
        *buf = '\0';    /* NUL-terminated */
89 144968
        return (l + 1);
90
}
91
92
/* These cannot be struct lock, which depends on vsm/vsl working */
93
static pthread_mutex_t vsl_mtx;
94
static pthread_mutex_t vsc_mtx;
95
static pthread_mutex_t vsm_mtx;
96
97
static struct VSL_head          *vsl_head;
98
static const uint32_t           *vsl_end;
99
static uint32_t                 *vsl_ptr;
100
static unsigned                 vsl_segment_n;
101
static ssize_t                  vsl_segsize;
102
103
struct VSC_main *VSC_C_main;
104
105
static void
106 1424526
vsl_sanity(const struct vsl_log *vsl)
107
{
108 1424526
        AN(vsl);
109 1424526
        AN(vsl->wlp);
110 1424526
        AN(vsl->wlb);
111 1424526
        AN(vsl->wle);
112 1424526
        assert(vsl->wlb <= vsl->wlp);
113 1424526
        assert(vsl->wlp <= vsl->wle);
114 1424526
}
115
116
/*--------------------------------------------------------------------
117
 * Check if the VSL_tag is masked by parameter bitmap
118
 */
119
120
static inline int
121 1067557
vsl_tag_is_masked(enum VSL_tag_e tag)
122
{
123 1067557
        volatile uint8_t *bm = &cache_param->vsl_mask[0];
124
        uint8_t b;
125
126 1067557
        assert(tag > SLT__Bogus);
127 1067557
        assert(tag < SLT__Reserved);
128 1067557
        bm += ((unsigned)tag >> 3);
129 1067557
        b = (0x80 >> ((unsigned)tag & 7));
130 1067557
        return (*bm & b);
131
}
132
133
int
134 3790
VSL_tag_is_masked(enum VSL_tag_e tag)
135
{
136 3790
        return (vsl_tag_is_masked(tag));
137
}
138
139
/*--------------------------------------------------------------------
140
 * Lay down a header fields, and return pointer to the next record
141
 */
142
143
static inline uint32_t *
144 878706
vsl_hdr(enum VSL_tag_e tag, uint32_t *p, unsigned len, vxid_t vxid)
145
{
146
147 878706
        AZ((uintptr_t)p & 0x3);
148 878706
        assert(tag > SLT__Bogus);
149 878706
        assert(tag < SLT__Reserved);
150 878706
        AZ(len & ~VSL_LENMASK);
151
152 878706
        p[2] = vxid.vxid >> 32;
153 878706
        p[1] = vxid.vxid;
154 1757412
        p[0] = (((unsigned)tag & VSL_IDMASK) << VSL_IDSHIFT) |
155 878706
             (VSL_VERSION_3 << VSL_VERSHIFT) |
156 878706
             len;
157 878706
        return (VSL_END(p, len));
158
}
159
160
/*--------------------------------------------------------------------
161
 * Space available in a VSL buffer when accounting for overhead
162
 */
163
164
static unsigned
165 212928
vsl_space(const struct vsl_log *vsl)
166
{
167
        ptrdiff_t mlen;
168
169 212928
        mlen = vsl->wle - vsl->wlp;
170 212928
        assert(mlen >= 0);
171 212928
        if (mlen < VSL_OVERHEAD + 1)
172 6
                return (0);
173 212922
        mlen -= VSL_OVERHEAD;
174 212922
        mlen *= sizeof *vsl->wlp;
175 212922
        if (mlen > cache_param->vsl_reclen)
176 212866
                mlen = cache_param->vsl_reclen;
177 212922
        return(mlen);
178 212928
}
179
180
/*--------------------------------------------------------------------
181
 * Wrap the VSL buffer
182
 */
183
184
static void
185 0
vsl_wrap(void)
186
{
187
188 0
        assert(vsl_ptr >= vsl_head->log);
189 0
        assert(vsl_ptr < vsl_end);
190 0
        vsl_segment_n += VSL_SEGMENTS - (vsl_segment_n % VSL_SEGMENTS);
191 0
        assert(vsl_segment_n % VSL_SEGMENTS == 0);
192 0
        vsl_head->offset[0] = 0;
193 0
        vsl_head->log[0] = VSL_ENDMARKER;
194 0
        VWMB();
195 0
        if (vsl_ptr != vsl_head->log) {
196 0
                *vsl_ptr = VSL_WRAPMARKER;
197 0
                vsl_ptr = vsl_head->log;
198 0
        }
199 0
        vsl_head->segment_n = vsl_segment_n;
200 0
        VSC_C_main->shm_cycles++;
201 0
}
202
203
/*--------------------------------------------------------------------
204
 * Reserve bytes for a record, wrap if necessary
205
 */
206
207
static uint32_t *
208 253510
vsl_get(unsigned len, unsigned records, unsigned flushes)
209
{
210
        uint32_t *p;
211
        int err;
212
213 253510
        err = pthread_mutex_trylock(&vsl_mtx);
214 253510
        if (err == EBUSY) {
215 1351
                PTOK(pthread_mutex_lock(&vsl_mtx));
216 1351
                VSC_C_main->shm_cont++;
217 1351
        } else {
218 252159
                AZ(err);
219
        }
220 253510
        assert(vsl_ptr < vsl_end);
221 253510
        AZ((uintptr_t)vsl_ptr & 0x3);
222
223 253510
        VSC_C_main->shm_writes++;
224 253510
        VSC_C_main->shm_flushes += flushes;
225 253510
        VSC_C_main->shm_records += records;
226 253510
        VSC_C_main->shm_bytes +=
227 253510
            VSL_BYTES(VSL_OVERHEAD + VSL_WORDS((uint64_t)len));
228
229
        /* Wrap if necessary */
230 253510
        if (VSL_END(vsl_ptr, len) >= vsl_end)
231 0
                vsl_wrap();
232
233 253510
        p = vsl_ptr;
234 253510
        vsl_ptr = VSL_END(vsl_ptr, len);
235 253510
        assert(vsl_ptr < vsl_end);
236 253510
        AZ((uintptr_t)vsl_ptr & 0x3);
237
238 253510
        *vsl_ptr = VSL_ENDMARKER;
239
240 253516
        while ((vsl_ptr - vsl_head->log) / vsl_segsize >
241 253516
            vsl_segment_n % VSL_SEGMENTS) {
242 6
                vsl_segment_n++;
243 6
                vsl_head->offset[vsl_segment_n % VSL_SEGMENTS] =
244 6
                    vsl_ptr - vsl_head->log;
245
        }
246
247 253510
        PTOK(pthread_mutex_unlock(&vsl_mtx));
248
        /* Implicit VWMB() in mutex op ensures ENDMARKER and new table
249
           values are seen before new segment number */
250 253510
        vsl_head->segment_n = vsl_segment_n;
251
252 253510
        return (p);
253
}
254
255
/*--------------------------------------------------------------------
256
 * Stick a finished record into VSL.
257
 */
258
259
static void
260 170082
vslr(enum VSL_tag_e tag, vxid_t vxid, const char *b, unsigned len)
261
{
262
        uint32_t *p;
263
        unsigned mlen;
264
265 170082
        mlen = cache_param->vsl_reclen;
266
267
        /* Truncate */
268 170082
        if (len > mlen)
269 0
                len = mlen;
270
271 170082
        p = vsl_get(len, 1, 0);
272
273 170082
        memcpy(p + VSL_OVERHEAD, b, len);
274
275
        /*
276
         * the vxid needs to be written before the barrier to
277
         * ensure it is valid when vsl_hdr() marks the record
278
         * ready by writing p[0]
279
         */
280 170082
        p[2] = vxid.vxid >> 32;
281 170082
        p[1] = vxid.vxid;
282 170082
        VWMB();
283 170082
        (void)vsl_hdr(tag, p, len, vxid);
284 170082
}
285
286
/*--------------------------------------------------------------------
287
 * Add a unbuffered record to VSL
288
 *
289
 * NB: This variant should be used sparingly and only for low volume
290
 * NB: since it significantly adds to the mutex load on the VSL.
291
 */
292
293
void
294 228582
VSLv(enum VSL_tag_e tag, vxid_t vxid, const char *fmt, va_list ap)
295
{
296 228582
        unsigned n, mlen = cache_param->vsl_reclen;
297 228582
        char buf[mlen];
298
299 228582
        AN(fmt);
300 228582
        if (vsl_tag_is_masked(tag))
301 59089
                return;
302
303 169493
        if (strchr(fmt, '%') == NULL) {
304 3346
                vslr(tag, vxid, fmt, strlen(fmt) + 1);
305 3346
        } else {
306 166147
                n = vsnprintf(buf, mlen, fmt, ap);
307 166147
                n = vmin(n, mlen - 1);
308 166147
                buf[n++] = '\0'; /* NUL-terminated */
309 166147
                vslr(tag, vxid, buf, n);
310
        }
311
312 228582
}
313
314
void
315 582
VSLs(enum VSL_tag_e tag, vxid_t vxid, const struct strands *s)
316
{
317 582
        unsigned n, mlen = cache_param->vsl_reclen;
318 582
        char buf[mlen];
319
320 582
        if (vsl_tag_is_masked(tag))
321 0
                return;
322
323 582
        n = strands_cat(buf, mlen, s);
324
325 582
        vslr(tag, vxid, buf, n);
326 582
}
327
328
void
329 223658
VSL(enum VSL_tag_e tag, vxid_t vxid, const char *fmt, ...)
330
{
331
        va_list ap;
332
333 223658
        va_start(ap, fmt);
334 223658
        VSLv(tag, vxid, fmt, ap);
335 223658
        va_end(ap);
336 223658
}
337
338
/*--------------------------------------------------------------------*/
339
340
void
341 106401
VSL_Flush(struct vsl_log *vsl, int overflow)
342
{
343
        uint32_t *p;
344
        unsigned l;
345
346 106401
        vsl_sanity(vsl);
347 106401
        l = pdiff(vsl->wlb, vsl->wlp);
348 106401
        if (l == 0)
349 23187
                return;
350
351 83214
        assert(l >= 8);
352
353 83214
        p = vsl_get(l, vsl->wlr, overflow);
354
355 83214
        memcpy(p + VSL_OVERHEAD, vsl->wlb, l);
356 83214
        p[1] = l;
357 83214
        VWMB();
358 83214
        p[0] = ((((unsigned)SLT__Batch & 0xff) << VSL_IDSHIFT));
359 83214
        vsl->wlp = vsl->wlb;
360 83214
        vsl->wlr = 0;
361 106401
}
362
363
/*--------------------------------------------------------------------
364
 * Buffered VSLs
365
 */
366
367
static char *
368 704580
vslb_get(struct vsl_log *vsl, enum VSL_tag_e tag, unsigned *length)
369
{
370 704580
        unsigned mlen = cache_param->vsl_reclen;
371
        char *retval;
372
373 704580
        vsl_sanity(vsl);
374 704580
        if (*length < mlen)
375 702845
                mlen = *length;
376
377 704580
        if (VSL_END(vsl->wlp, mlen) > vsl->wle)
378 21
                VSL_Flush(vsl, 1);
379
380 704580
        retval = VSL_DATA(vsl->wlp);
381
382
        /* If it still doesn't fit, truncate */
383 704580
        if (VSL_END(vsl->wlp, mlen) > vsl->wle)
384 6
                mlen = vsl_space(vsl);
385
386 704580
        vsl->wlp = vsl_hdr(tag, vsl->wlp, mlen, vsl->wid);
387 704580
        vsl->wlr++;
388 704580
        *length = mlen;
389 704580
        return (retval);
390
}
391
392
static void
393 347554
vslb_simple(struct vsl_log *vsl, enum VSL_tag_e tag,
394
    unsigned length, const char *str)
395
{
396
        char *p;
397
398 347554
        if (length == 0)
399 27318
                length = strlen(str);
400 347554
        length += 1; // NUL
401 347554
        p = vslb_get(vsl, tag, &length);
402 347554
        memcpy(p, str, length - 1);
403 347554
        p[length - 1] = '\0';
404
405 347554
        if (DO_DEBUG(DBG_SYNCVSL))
406 30172
                VSL_Flush(vsl, 0);
407 347554
}
408
409
/*--------------------------------------------------------------------
410
 * VSL-buffered-txt
411
 */
412
413
void
414 390506
VSLbt(struct vsl_log *vsl, enum VSL_tag_e tag, txt t)
415
{
416
417 390506
        Tcheck(t);
418 390506
        if (vsl_tag_is_masked(tag))
419 51970
                return;
420
421 338536
        vslb_simple(vsl, tag, Tlen(t), t.b);
422 390506
}
423
424
/*--------------------------------------------------------------------
425
 * VSL-buffered-strands
426
 */
427
void
428 171149
VSLbs(struct vsl_log *vsl, enum VSL_tag_e tag, const struct strands *s)
429
{
430
        unsigned l;
431
        char *p;
432
433 171149
        if (vsl_tag_is_masked(tag))
434 26744
                return;
435
436 144405
        l = strands_len(s) + 1;
437 144405
        p = vslb_get(vsl, tag, &l);
438
439 144405
        (void)strands_cat(p, l, s);
440
441 144405
        if (DO_DEBUG(DBG_SYNCVSL))
442 12023
                VSL_Flush(vsl, 0);
443 171149
}
444
445
/*--------------------------------------------------------------------
446
 * VSL-buffered
447
 */
448
449
void
450 265246
VSLbv(struct vsl_log *vsl, enum VSL_tag_e tag, const char *fmt, va_list ap)
451
{
452
        char *p, *p1;
453 265246
        unsigned n = 0, mlen;
454
        va_list ap2;
455
456 265246
        AN(fmt);
457 265246
        if (vsl_tag_is_masked(tag))
458 43284
                return;
459
460
        /*
461
         * If there are no printf-expansions, don't waste time expanding them
462
         */
463 221962
        if (strchr(fmt, '%') == NULL) {
464 8973
                vslb_simple(vsl, tag, 0, fmt);
465 8973
                return;
466
        }
467
468
        /*
469
         * If the format is trivial, deal with it directly
470
         */
471 212989
        if (!strcmp(fmt, "%s")) {
472 54
                p1 = va_arg(ap, char *);
473 54
                vslb_simple(vsl, tag, 0, p1);
474 54
                return;
475
        }
476
477 212935
        vsl_sanity(vsl);
478
479 212935
        mlen = vsl_space(vsl);
480
481
        // First attempt, only if any space at all
482 212935
        if (mlen > 0) {
483 212853
                p = VSL_DATA(vsl->wlp);
484 212853
                va_copy(ap2, ap);
485 212853
                n = vsnprintf(p, mlen, fmt, ap2);
486 212853
                va_end(ap2);
487 212853
        }
488
489
        // Second attempt, if a flush might help
490 212935
        if (mlen == 0 || (n + 1 > mlen && n + 1 <= cache_param->vsl_reclen)) {
491 236
                VSL_Flush(vsl, 1);
492 236
                mlen = vsl_space(vsl);
493 236
                p = VSL_DATA(vsl->wlp);
494 236
                n = vsnprintf(p, mlen, fmt, ap);
495 236
        }
496 212971
        if (n + 1 < mlen)
497 212189
                mlen = n + 1;
498 212971
        (void)vslb_get(vsl, tag, &mlen);
499
500 212971
        if (DO_DEBUG(DBG_SYNCVSL))
501 22208
                VSL_Flush(vsl, 0);
502 265282
}
503
504
void
505 254912
VSLb(struct vsl_log *vsl, enum VSL_tag_e tag, const char *fmt, ...)
506
{
507
        va_list ap;
508
509 254912
        vsl_sanity(vsl);
510 254912
        va_start(ap, fmt);
511 254912
        VSLbv(vsl, tag, fmt, ap);
512 254912
        va_end(ap);
513 254912
}
514
515
#define Tf6 "%ju.%06ju"
516
#define Ta6(t) (uintmax_t)floor((t)), (uintmax_t)floor((t) * 1e6) % 1000000U
517
518
void
519 96534
VSLb_ts(struct vsl_log *vsl, const char *event, vtim_real first,
520
    vtim_real *pprev, vtim_real now)
521
{
522
523
        /*
524
         * XXX: Make an option to turn off some unnecessary timestamp
525
         * logging. This must be done carefully because some functions
526
         * (e.g. V1L_Open) takes the last timestamp as its initial
527
         * value for timeout calculation.
528
         */
529 96534
        vsl_sanity(vsl);
530 96534
        AN(event);
531 96534
        AN(pprev);
532 96534
        assert(!isnan(now) && now != 0.);
533 193068
        VSLb(vsl, SLT_Timestamp, "%s: " Tf6 " " Tf6 " " Tf6,
534 96534
            event, Ta6(now), Ta6(now - first), Ta6(now - *pprev));
535 96534
        *pprev = now;
536 96534
}
537
538
void
539 8303
VSLb_bin(struct vsl_log *vsl, enum VSL_tag_e tag, ssize_t len, const void *ptr)
540
{
541
        unsigned mlen;
542
        char *p;
543
544 8303
        vsl_sanity(vsl);
545 8303
        AN(ptr);
546 8303
        if (vsl_tag_is_masked(tag))
547 3884
                return;
548 4419
        mlen = cache_param->vsl_reclen;
549
550
        /* Truncate */
551 4419
        len = vmin_t(ssize_t, len, mlen);
552
553 4419
        assert(vsl->wlp <= vsl->wle);
554
555
        /* Flush if necessary */
556 4419
        if (VSL_END(vsl->wlp, len) > vsl->wle)
557 27
                VSL_Flush(vsl, 1);
558 4419
        assert(VSL_END(vsl->wlp, len) <= vsl->wle);
559 4419
        p = VSL_DATA(vsl->wlp);
560 4419
        memcpy(p, ptr, len);
561 4419
        vsl->wlp = vsl_hdr(tag, vsl->wlp, len, vsl->wid);
562 4419
        assert(vsl->wlp <= vsl->wle);
563 4419
        vsl->wlr++;
564
565 4419
        if (DO_DEBUG(DBG_SYNCVSL))
566 1821
                VSL_Flush(vsl, 0);
567 8303
}
568
569
/*--------------------------------------------------------------------
570
 * Setup a VSL buffer, allocate space if none provided.
571
 */
572
573
void
574 24160
VSL_Setup(struct vsl_log *vsl, void *ptr, size_t len)
575
{
576
577 24160
        if (ptr == NULL) {
578 8352
                len = cache_param->vsl_buffer;
579 8352
                ptr = malloc(len);
580 8352
                AN(ptr);
581 8352
        }
582 24160
        vsl->wlp = ptr;
583 24160
        vsl->wlb = ptr;
584 24160
        vsl->wle = ptr;
585 24160
        vsl->wle += len / sizeof(*vsl->wle);
586 24160
        vsl->wlr = 0;
587 24160
        vsl->wid = NO_VXID;
588 24160
        vsl_sanity(vsl);
589 24160
}
590
591
/*--------------------------------------------------------------------*/
592
593
void
594 288
VSL_ChgId(struct vsl_log *vsl, const char *typ, const char *why, vxid_t vxid)
595
{
596
        vxid_t ovxid;
597
598 288
        vsl_sanity(vsl);
599 288
        ovxid = vsl->wid;
600 288
        VSLb(vsl, SLT_Link, "%s %ju %s", typ, VXID(vxid), why);
601 288
        VSL_End(vsl);
602 288
        vsl->wid = vxid;
603 288
        VSLb(vsl, SLT_Begin, "%s %ju %s", typ, VXID(ovxid), why);
604 288
}
605
606
/*--------------------------------------------------------------------*/
607
608
void
609 18291
VSL_End(struct vsl_log *vsl)
610
{
611
        txt t;
612 18291
        char p[] = "";
613
614 18291
        vsl_sanity(vsl);
615 18291
        assert(!IS_NO_VXID(vsl->wid));
616 18291
        t.b = p;
617 18291
        t.e = p;
618 18291
        VSLbt(vsl, SLT_End, t);
619 18291
        VSL_Flush(vsl, 0);
620 18291
        vsl->wid = NO_VXID;
621 18291
}
622
623
static void v_matchproto_(vsm_lock_f)
624 99575
vsm_vsc_lock(void)
625
{
626 99575
        PTOK(pthread_mutex_lock(&vsc_mtx));
627 99575
}
628
629
static void v_matchproto_(vsm_lock_f)
630 99575
vsm_vsc_unlock(void)
631
{
632 99575
        PTOK(pthread_mutex_unlock(&vsc_mtx));
633 99575
}
634
635
static void v_matchproto_(vsm_lock_f)
636 121884
vsm_vsmw_lock(void)
637
{
638 121884
        PTOK(pthread_mutex_lock(&vsm_mtx));
639 121884
}
640
641
static void v_matchproto_(vsm_lock_f)
642 121884
vsm_vsmw_unlock(void)
643
{
644 121884
        PTOK(pthread_mutex_unlock(&vsm_mtx));
645 121884
}
646
647
/*--------------------------------------------------------------------*/
648
649
void
650 2786
VSM_Init(void)
651
{
652
        unsigned u;
653
654 2786
        assert(UINT_MAX % VSL_SEGMENTS == VSL_SEGMENTS - 1);
655
656 2786
        PTOK(pthread_mutex_init(&vsl_mtx, &mtxattr_errorcheck));
657 2786
        PTOK(pthread_mutex_init(&vsc_mtx, &mtxattr_errorcheck));
658 2786
        PTOK(pthread_mutex_init(&vsm_mtx, &mtxattr_errorcheck));
659
660 2786
        vsc_lock = vsm_vsc_lock;
661 2786
        vsc_unlock = vsm_vsc_unlock;
662 2786
        vsmw_lock = vsm_vsmw_lock;
663 2786
        vsmw_unlock = vsm_vsmw_unlock;
664
665 2786
        heritage.proc_vsmw = VSMW_New(heritage.vsm_fd, 0640, "_.index");
666 2786
        AN(heritage.proc_vsmw);
667
668 2786
        VSC_C_main = VSC_main_New(NULL, NULL, "");
669 2786
        AN(VSC_C_main);
670
671 2786
        AN(heritage.proc_vsmw);
672 5572
        vsl_head = VSMW_Allocf(heritage.proc_vsmw, NULL, VSL_CLASS,
673 2786
            cache_param->vsl_space, VSL_CLASS);
674 2786
        AN(vsl_head);
675 5572
        vsl_segsize = ((cache_param->vsl_space - sizeof *vsl_head) /
676 2786
            sizeof *vsl_end) / VSL_SEGMENTS;
677 2786
        vsl_end = vsl_head->log + vsl_segsize * VSL_SEGMENTS;
678
        /* Make segment_n always overflow on first log wrap to make any
679
           problems with regard to readers on that event visible */
680 2786
        vsl_segment_n = UINT_MAX - (VSL_SEGMENTS - 1);
681 2786
        AZ(vsl_segment_n % VSL_SEGMENTS);
682 2786
        vsl_ptr = vsl_head->log;
683 2786
        *vsl_ptr = VSL_ENDMARKER;
684
685 2786
        memset(vsl_head, 0, sizeof *vsl_head);
686 2786
        vsl_head->segsize = vsl_segsize;
687 2786
        vsl_head->offset[0] = 0;
688 2786
        vsl_head->segment_n = vsl_segment_n;
689 22288
        for (u = 1; u < VSL_SEGMENTS; u++)
690 19502
                vsl_head->offset[u] = -1;
691 2786
        VWMB();
692 2786
        memcpy(vsl_head->marker, VSL_HEAD_MARKER, sizeof vsl_head->marker);
693 2786
}