varnish-cache/vmod/vmod_directors.c
0
/*-
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 * Copyright (c) 2013-2015 Varnish Software AS
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 * Copyright 2019 UPLEX - Nils Goroll Systemoptimierung
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 * All rights reserved.
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 *
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 * Author: Poul-Henning Kamp <phk@FreeBSD.org>
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 * Author: Nils Goroll <nils.goroll@uplex.de>
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 *
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 * SPDX-License-Identifier: BSD-2-Clause
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include "config.h"
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34
#include <stdlib.h>
35
#include <stdio.h>
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37
#include "cache/cache.h"
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39
#include "vbm.h"
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#include "vcl.h"
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#include "vsb.h"
42
43
#include "vcc_directors_if.h"
44
45
#include "vmod_directors.h"
46
47
VCL_BACKEND
48 16
VPFX(lookup)(VRT_CTX, VCL_STRING name)
49
{
50 16
        AN(ctx->method & VCL_MET_TASK_H);
51 16
        return (VRT_LookupDirector(ctx, name));
52
}
53
54
static void
55 528
vdir_expand(struct vdir *vd, unsigned n)
56
{
57 528
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
58
59 528
        vd->backend = realloc(vd->backend, n * sizeof *vd->backend);
60 528
        AN(vd->backend);
61 528
        vd->weight = realloc(vd->weight, n * sizeof *vd->weight);
62 528
        AN(vd->weight);
63 528
        if (n > vd->healthy->nbits)
64 0
                vbit_expand(vd->healthy, n);
65 528
        AN(vd->healthy);
66 528
        vd->l_backend = n;
67 528
}
68
69
void
70 576
vdir_new(VRT_CTX, struct vdir **vdp, const char *vcl_name,
71
    const struct vdi_methods *m, void *priv)
72
{
73
        struct vdir *vd;
74
75 576
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
76 576
        CHECK_OBJ_NOTNULL(m, VDI_METHODS_MAGIC);
77 576
        AN(vcl_name);
78 576
        AN(vdp);
79 576
        AZ(*vdp);
80 576
        ALLOC_OBJ(vd, VDIR_MAGIC);
81 576
        AN(vd);
82 576
        *vdp = vd;
83 576
        PTOK(pthread_rwlock_init(&vd->mtx, NULL));
84 576
        vd->dir = VRT_AddDirector(ctx, m, priv, "%s", vcl_name);
85 576
        vd->healthy = vbit_new(8);
86 576
        AN(vd->healthy);
87 576
}
88
89
void
90 128
vdir_release(struct vdir *vd)
91
{
92
        unsigned u;
93
94 128
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
95
96 128
        vdir_wrlock(vd);
97 320
        for (u = 0; u < vd->n_backend; u++)
98 192
                VRT_Assign_Backend(&vd->backend[u], NULL);
99 128
        vd->n_backend = 0;
100 128
        vdir_unlock(vd);
101 128
}
102
103
void
104 128
vdir_delete(struct vdir **vdp)
105
{
106
        struct vdir *vd;
107
108 128
        TAKE_OBJ_NOTNULL(vd, vdp, VDIR_MAGIC);
109
110 128
        AZ(vd->dir);
111 128
        AZ(vd->n_backend);
112 128
        free(vd->backend);
113 128
        free(vd->weight);
114 128
        PTOK(pthread_rwlock_destroy(&vd->mtx));
115 128
        vbit_destroy(vd->healthy);
116 128
        FREE_OBJ(vd);
117 128
}
118
119
void
120 2512
vdir_rdlock(struct vdir *vd)
121
{
122 2512
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
123 2512
        PTOK(pthread_rwlock_rdlock(&vd->mtx));
124 2512
}
125
126
void
127 2896
vdir_wrlock(struct vdir *vd)
128
{
129 2896
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
130 2896
        PTOK(pthread_rwlock_wrlock(&vd->mtx));
131 2896
}
132
133
void
134 5408
vdir_unlock(struct vdir *vd)
135
{
136 5408
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
137 5408
        PTOK(pthread_rwlock_unlock(&vd->mtx));
138 5408
}
139
140
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void
142 1440
vdir_add_backend(VRT_CTX, struct vdir *vd, VCL_BACKEND be, double weight)
143
{
144
        unsigned u;
145
146 1440
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
147 1440
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
148 1440
        if (be == NULL) {
149 96
                VRT_fail(ctx, "%s: None backend cannot be added",
150 48
                    VRT_BACKEND_string(vd->dir));
151 48
                return;
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        }
153 1392
        AN(be);
154 1392
        vdir_wrlock(vd);
155 1392
        if (vd->n_backend >= vd->l_backend)
156 528
                vdir_expand(vd, vd->l_backend + 16);
157 1392
        assert(vd->n_backend < vd->l_backend);
158 1392
        u = vd->n_backend++;
159 1392
        vd->backend[u] = NULL;
160 1392
        VRT_Assign_Backend(&vd->backend[u], be);
161 1392
        vd->weight[u] = weight;
162 1392
        vdir_unlock(vd);
163 1440
}
164
165
void
166 192
vdir_remove_backend(VRT_CTX, struct vdir *vd, VCL_BACKEND be, unsigned *cur)
167
{
168
        unsigned u, n;
169
170 192
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
171 192
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
172 192
        if (be == NULL) {
173 0
                VRT_fail(ctx, "%s: None backend cannot be removed",
174 0
                    VRT_BACKEND_string(vd->dir));
175 0
                return;
176
        }
177 192
        CHECK_OBJ(be, DIRECTOR_MAGIC);
178 192
        vdir_wrlock(vd);
179 272
        for (u = 0; u < vd->n_backend; u++)
180 272
                if (vd->backend[u] == be)
181 192
                        break;
182 192
        if (u == vd->n_backend) {
183 0
                vdir_unlock(vd);
184 0
                return;
185
        }
186 192
        VRT_Assign_Backend(&vd->backend[u], NULL);
187 192
        n = (vd->n_backend - u) - 1;
188 192
        memmove(&vd->backend[u], &vd->backend[u+1], n * sizeof(vd->backend[0]));
189 192
        memmove(&vd->weight[u], &vd->weight[u+1], n * sizeof(vd->weight[0]));
190 192
        vd->n_backend--;
191
192 192
        if (cur) {
193 64
                assert(*cur <= vd->n_backend);
194 64
                if (u < *cur)
195 16
                        (*cur)--;
196 48
                else if (*cur == vd->n_backend)
197 16
                        *cur = 0;
198 64
        }
199 192
        vdir_unlock(vd);
200 192
}
201
202
VCL_BOOL
203 784
vdir_any_healthy(VRT_CTX, struct vdir *vd, VCL_TIME *changed)
204
{
205 784
        unsigned retval = 0;
206
        VCL_BACKEND be;
207
        unsigned u;
208
        vtim_real c;
209
210 784
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
211 784
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
212 784
        vdir_rdlock(vd);
213 784
        if (changed != NULL)
214 160
                *changed = 0;
215 1120
        for (u = 0; u < vd->n_backend; u++) {
216 1008
                be = vd->backend[u];
217 1008
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
218 1008
                retval = VRT_Healthy(ctx, be, &c);
219 1008
                if (changed != NULL && c > *changed)
220 208
                        *changed = c;
221 1008
                if (retval)
222 672
                        break;
223 336
        }
224 784
        vdir_unlock(vd);
225 784
        return (retval);
226
}
227
228
void
229 832
vdir_list(VRT_CTX, struct vdir *vd, struct vsb *vsb, int pflag, int jflag,
230
    int weight)
231
{
232
        VCL_BACKEND be;
233
        VCL_BOOL h;
234
        unsigned u, nh;
235
        double w;
236
237 832
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
238 832
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
239
240 832
        if (pflag) {
241 128
                if (jflag) {
242 64
                        VSB_cat(vsb, "{\n");
243 64
                        VSB_indent(vsb, 2);
244 64
                        if (weight)
245 32
                                VSB_printf(vsb, "\"total_weight\": %f,\n",
246 16
                                    vd->total_weight);
247 64
                        VSB_cat(vsb, "\"backends\": {\n");
248 64
                        VSB_indent(vsb, 2);
249 64
                } else {
250 64
                        VSB_cat(vsb, "\n\n\tBackend\tWeight\tHealth\n");
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                }
252 128
        }
253
254 832
        vdir_rdlock(vd);
255 832
        vdir_update_health(ctx, vd);
256 1184
        for (u = 0; pflag && u < vd->n_backend; u++) {
257 352
                be = vd->backend[u];
258 352
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
259
260 352
                h = vbit_test(vd->healthy, u);
261
262 352
                w = h ? vd->weight[u] : 0.0;
263
264 352
                if (jflag) {
265 176
                        if (u)
266 112
                                VSB_cat(vsb, ",\n");
267 176
                        VSB_printf(vsb, "\"%s\": {\n", be->vcl_name);
268 176
                        VSB_indent(vsb, 2);
269
270 176
                        if (weight)
271 64
                                VSB_printf(vsb, "\"weight\": %f,\n", w);
272
273 176
                        if (h)
274 128
                                VSB_cat(vsb, "\"health\": \"healthy\"\n");
275
                        else
276 48
                                VSB_cat(vsb, "\"health\": \"sick\"\n");
277
278 176
                        VSB_indent(vsb, -2);
279 176
                        VSB_cat(vsb, "}");
280 176
                } else {
281 176
                        VSB_cat(vsb, "\t");
282 176
                        VSB_cat(vsb, be->vcl_name);
283 176
                        if (weight)
284 128
                                VSB_printf(vsb, "\t%6.2f%%\t",
285 64
                                    100 * w / vd->total_weight);
286
                        else
287 112
                                VSB_cat(vsb, "\t-\t");
288 176
                        VSB_cat(vsb, h ? "healthy" : "sick");
289 176
                        VSB_cat(vsb, "\n");
290
                }
291 352
        }
292 832
        nh = vd->n_healthy;
293 832
        u = vd->n_backend;
294 832
        vdir_unlock(vd);
295
296 832
        if (jflag && (pflag)) {
297 64
                VSB_cat(vsb, "\n");
298 64
                VSB_indent(vsb, -2);
299 64
                VSB_cat(vsb, "}\n");
300 64
                VSB_indent(vsb, -2);
301 64
                VSB_cat(vsb, "},\n");
302 64
        }
303
304 832
        if (pflag)
305 128
                return;
306
307 704
        if (jflag)
308 320
                VSB_printf(vsb, "[%u, %u, \"%s\"]", nh, u,
309 160
                    nh ? "healthy" : "sick");
310
        else
311 544
                VSB_printf(vsb, "%u/%u\t%s", nh, u, nh ? "healthy" : "sick");
312 832
}
313
314
/*
315
 * iterate backends and update
316
 * - healthy bitmap
317
 * - number of healthy backends
318
 * - total_weight
319
 * - last change time of the VCL_BACKEND
320
 *
321
 * must be called under the vdir lock (read or write).
322
 *
323
 * A write lock is required if consistency between the individual attributes is
324
 * a must, e.g. when total_weight is required to be the exact sum of the weights
325
 *
326
 * The read lock is safe because add_backend expands the healthy bitmap and all
327
 * other members are atomic and may be used if consistency is not required.
328
 */
329
void
330 1792
vdir_update_health(VRT_CTX, struct vdir *vd)
331
{
332 1792
        VCL_TIME c, changed = 0;
333
        VCL_BOOL h;
334
        VCL_BACKEND be;
335 1792
        unsigned u, nh = 0;
336 1792
        double tw = 0.0;
337
        struct vbitmap *healthy;
338
339 1792
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
340 1792
        healthy = vd->healthy;
341 5984
        for (u = 0; u < vd->n_backend; u++) {
342 4192
                be = vd->backend[u];
343 4192
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
344 4192
                c = 0;
345 4192
                h = VRT_Healthy(ctx, vd->backend[u], &c);
346 4192
                if (h) {
347 3248
                        nh++;
348 3248
                        tw += vd->weight[u];
349 3248
                }
350 4192
                if (c > changed)
351 4032
                        changed = c;
352 4192
                if (h != vbit_test(healthy, u)) {
353 2144
                        if (h)
354 2112
                                vbit_set(healthy, u);
355
                        else
356 32
                                vbit_clr(healthy, u);
357 2144
                }
358 4192
        }
359 1792
        VRT_SetChanged(vd->dir, changed);
360 1792
        vd->total_weight = tw;
361 1792
        vd->n_healthy = nh;
362 1792
}
363
364
static unsigned
365 736
vdir_pick_by_weight(const struct vdir *vd, double w)
366
{
367 736
        const struct vbitmap *healthy = vd->healthy;
368 736
        double a = 0.0;
369
        unsigned u;
370
371 736
        AN(healthy);
372 1119
        for (u = 0; u < vd->n_backend; u++) {
373 1119
                if (! vbit_test(healthy, u))
374 64
                        continue;
375 1055
                a += vd->weight[u];
376 1055
                if (w < a)
377 736
                        return (u);
378 319
        }
379 0
        WRONG("");
380
}
381
382
VCL_BACKEND
383 752
vdir_pick_be(VRT_CTX, struct vdir *vd, double w)
384
{
385
        unsigned u;
386 752
        VCL_BACKEND be = NULL;
387
388 752
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
389 752
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
390 752
        vdir_wrlock(vd);
391 752
        vdir_update_health(ctx, vd);
392 752
        if (vd->total_weight > 0.0) {
393 736
                u = vdir_pick_by_weight(vd, w * vd->total_weight);
394 736
                assert(u < vd->n_backend);
395 736
                be = vd->backend[u];
396 736
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
397 736
        }
398 752
        vdir_unlock(vd);
399 752
        return (be);
400
}