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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 *
10
 * 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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 */
31
32
#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"
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43
#include "vcc_directors_if.h"
44
45
#include "vmod_directors.h"
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47
VCL_BACKEND
48 40
VPFX(lookup)(VRT_CTX, VCL_STRING name)
49
{
50 40
        AN(ctx->method & VCL_MET_TASK_H);
51 40
        return (VRT_LookupDirector(ctx, name));
52
}
53
54
static void
55 1320
vdir_expand(struct vdir *vd, unsigned n)
56
{
57 1320
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
58
59 1320
        vd->backend = realloc(vd->backend, n * sizeof *vd->backend);
60 1320
        AN(vd->backend);
61 1320
        vd->weight = realloc(vd->weight, n * sizeof *vd->weight);
62 1320
        AN(vd->weight);
63 1320
        if (n > vd->healthy->nbits)
64 0
                vbit_expand(vd->healthy, n);
65 1320
        AN(vd->healthy);
66 1320
        vd->l_backend = n;
67 1320
}
68
69
void
70 1440
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 1440
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
76 1440
        CHECK_OBJ_NOTNULL(m, VDI_METHODS_MAGIC);
77 1440
        AN(vcl_name);
78 1440
        AN(vdp);
79 1440
        AZ(*vdp);
80 1440
        ALLOC_OBJ(vd, VDIR_MAGIC);
81 1440
        AN(vd);
82 1440
        *vdp = vd;
83 1440
        PTOK(pthread_rwlock_init(&vd->mtx, NULL));
84 1440
        vd->dir = VRT_AddDirector(ctx, m, priv, "%s", vcl_name);
85 1440
        vd->healthy = vbit_new(8);
86 1440
        AN(vd->healthy);
87 1440
}
88
89
void
90 320
vdir_release(struct vdir *vd)
91
{
92
        unsigned u;
93
94 320
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
95
96 320
        vdir_wrlock(vd);
97 800
        for (u = 0; u < vd->n_backend; u++)
98 480
                VRT_Assign_Backend(&vd->backend[u], NULL);
99 320
        vd->n_backend = 0;
100 320
        vdir_unlock(vd);
101 320
}
102
103
void
104 320
vdir_delete(struct vdir **vdp)
105
{
106
        struct vdir *vd;
107
108 320
        TAKE_OBJ_NOTNULL(vd, vdp, VDIR_MAGIC);
109
110 320
        AZ(vd->dir);
111 320
        AZ(vd->n_backend);
112 320
        free(vd->backend);
113 320
        free(vd->weight);
114 320
        PTOK(pthread_rwlock_destroy(&vd->mtx));
115 320
        vbit_destroy(vd->healthy);
116 320
        FREE_OBJ(vd);
117 320
}
118
119
void
120 6280
vdir_rdlock(struct vdir *vd)
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{
122 6280
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
123 6280
        PTOK(pthread_rwlock_rdlock(&vd->mtx));
124 6280
}
125
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void
127 7240
vdir_wrlock(struct vdir *vd)
128
{
129 7240
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
130 7240
        PTOK(pthread_rwlock_wrlock(&vd->mtx));
131 7240
}
132
133
void
134 13520
vdir_unlock(struct vdir *vd)
135
{
136 13520
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
137 13520
        PTOK(pthread_rwlock_unlock(&vd->mtx));
138 13520
}
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140
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void
142 3600
vdir_add_backend(VRT_CTX, struct vdir *vd, VCL_BACKEND be, double weight)
143
{
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        unsigned u;
145
146 3600
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
147 3600
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
148 3600
        if (be == NULL) {
149 240
                VRT_fail(ctx, "%s: None backend cannot be added",
150 120
                    VRT_BACKEND_string(vd->dir));
151 120
                return;
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        }
153 3480
        AN(be);
154 3480
        vdir_wrlock(vd);
155 3480
        if (vd->n_backend >= vd->l_backend)
156 1320
                vdir_expand(vd, vd->l_backend + 16);
157 3480
        assert(vd->n_backend < vd->l_backend);
158 3480
        u = vd->n_backend++;
159 3480
        vd->backend[u] = NULL;
160 3480
        VRT_Assign_Backend(&vd->backend[u], be);
161 3480
        vd->weight[u] = weight;
162 3480
        vdir_unlock(vd);
163 3600
}
164
165
void
166 480
vdir_remove_backend(VRT_CTX, struct vdir *vd, VCL_BACKEND be, unsigned *cur)
167
{
168
        unsigned u, n;
169
170 480
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
171 480
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
172 480
        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
        }
177 480
        CHECK_OBJ(be, DIRECTOR_MAGIC);
178 480
        vdir_wrlock(vd);
179 680
        for (u = 0; u < vd->n_backend; u++)
180 680
                if (vd->backend[u] == be)
181 480
                        break;
182 480
        if (u == vd->n_backend) {
183 0
                vdir_unlock(vd);
184 0
                return;
185
        }
186 480
        VRT_Assign_Backend(&vd->backend[u], NULL);
187 480
        n = (vd->n_backend - u) - 1;
188 480
        memmove(&vd->backend[u], &vd->backend[u+1], n * sizeof(vd->backend[0]));
189 480
        memmove(&vd->weight[u], &vd->weight[u+1], n * sizeof(vd->weight[0]));
190 480
        vd->n_backend--;
191
192 480
        if (cur) {
193 160
                assert(*cur <= vd->n_backend);
194 160
                if (u < *cur)
195 40
                        (*cur)--;
196 120
                else if (*cur == vd->n_backend)
197 40
                        *cur = 0;
198 160
        }
199 480
        vdir_unlock(vd);
200 480
}
201
202
VCL_BOOL
203 1960
vdir_any_healthy(VRT_CTX, struct vdir *vd, VCL_TIME *changed)
204
{
205 1960
        unsigned retval = 0;
206
        VCL_BACKEND be;
207
        unsigned u;
208
        vtim_real c;
209
210 1960
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
211 1960
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
212 1960
        vdir_rdlock(vd);
213 1960
        if (changed != NULL)
214 400
                *changed = 0;
215 2800
        for (u = 0; u < vd->n_backend; u++) {
216 2520
                be = vd->backend[u];
217 2520
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
218 2520
                retval = VRT_Healthy(ctx, be, &c);
219 2520
                if (changed != NULL && c > *changed)
220 520
                        *changed = c;
221 2520
                if (retval)
222 1680
                        break;
223 840
        }
224 1960
        vdir_unlock(vd);
225 1960
        return (retval);
226
}
227
228
void
229 2080
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 2080
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
238 2080
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
239
240 2080
        if (pflag) {
241 320
                if (jflag) {
242 160
                        VSB_cat(vsb, "{\n");
243 160
                        VSB_indent(vsb, 2);
244 160
                        if (weight)
245 80
                                VSB_printf(vsb, "\"total_weight\": %f,\n",
246 40
                                    vd->total_weight);
247 160
                        VSB_cat(vsb, "\"backends\": {\n");
248 160
                        VSB_indent(vsb, 2);
249 160
                } else {
250 160
                        VSB_cat(vsb, "\n\n\tBackend\tWeight\tHealth\n");
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                }
252 320
        }
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254 2080
        vdir_rdlock(vd);
255 2080
        vdir_update_health(ctx, vd);
256 2960
        for (u = 0; pflag && u < vd->n_backend; u++) {
257 880
                be = vd->backend[u];
258 880
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
259
260 880
                h = vbit_test(vd->healthy, u);
261
262 880
                w = h ? vd->weight[u] : 0.0;
263
264 880
                if (jflag) {
265 440
                        if (u)
266 280
                                VSB_cat(vsb, ",\n");
267 440
                        VSB_printf(vsb, "\"%s\": {\n", be->vcl_name);
268 440
                        VSB_indent(vsb, 2);
269
270 440
                        if (weight)
271 160
                                VSB_printf(vsb, "\"weight\": %f,\n", w);
272
273 440
                        if (h)
274 320
                                VSB_cat(vsb, "\"health\": \"healthy\"\n");
275
                        else
276 120
                                VSB_cat(vsb, "\"health\": \"sick\"\n");
277
278 440
                        VSB_indent(vsb, -2);
279 440
                        VSB_cat(vsb, "}");
280 440
                } else {
281 440
                        VSB_cat(vsb, "\t");
282 440
                        VSB_cat(vsb, be->vcl_name);
283 440
                        if (weight)
284 320
                                VSB_printf(vsb, "\t%6.2f%%\t",
285 160
                                    100 * w / vd->total_weight);
286
                        else
287 280
                                VSB_cat(vsb, "\t-\t");
288 440
                        VSB_cat(vsb, h ? "healthy" : "sick");
289 440
                        VSB_cat(vsb, "\n");
290
                }
291 880
        }
292 2080
        nh = vd->n_healthy;
293 2080
        u = vd->n_backend;
294 2080
        vdir_unlock(vd);
295
296 2080
        if (jflag && (pflag)) {
297 160
                VSB_cat(vsb, "\n");
298 160
                VSB_indent(vsb, -2);
299 160
                VSB_cat(vsb, "}\n");
300 160
                VSB_indent(vsb, -2);
301 160
                VSB_cat(vsb, "},\n");
302 160
        }
303
304 2080
        if (pflag)
305 320
                return;
306
307 1760
        if (jflag)
308 800
                VSB_printf(vsb, "[%u, %u, \"%s\"]", nh, u,
309 400
                    nh ? "healthy" : "sick");
310
        else
311 1360
                VSB_printf(vsb, "%u/%u\t%s", nh, u, nh ? "healthy" : "sick");
312 2080
}
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 4480
vdir_update_health(VRT_CTX, struct vdir *vd)
331
{
332 4480
        VCL_TIME c, changed = 0;
333
        VCL_BOOL h;
334
        VCL_BACKEND be;
335 4480
        unsigned u, nh = 0;
336 4480
        double tw = 0.0;
337
        struct vbitmap *healthy;
338
339 4480
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
340 4480
        healthy = vd->healthy;
341 14960
        for (u = 0; u < vd->n_backend; u++) {
342 10480
                be = vd->backend[u];
343 10480
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
344 10480
                c = 0;
345 10480
                h = VRT_Healthy(ctx, vd->backend[u], &c);
346 10480
                if (h) {
347 8120
                        nh++;
348 8120
                        tw += vd->weight[u];
349 8120
                }
350 10480
                if (c > changed)
351 10080
                        changed = c;
352 10480
                if (h != vbit_test(healthy, u)) {
353 5360
                        if (h)
354 5280
                                vbit_set(healthy, u);
355
                        else
356 80
                                vbit_clr(healthy, u);
357 5360
                }
358 10480
        }
359 4480
        VRT_SetChanged(vd->dir, changed);
360 4480
        vd->total_weight = tw;
361 4480
        vd->n_healthy = nh;
362 4480
}
363
364
static unsigned
365 1840
vdir_pick_by_weight(const struct vdir *vd, double w)
366
{
367 1840
        const struct vbitmap *healthy = vd->healthy;
368 1840
        double a = 0.0;
369
        unsigned u;
370
371 1840
        AN(healthy);
372 2799
        for (u = 0; u < vd->n_backend; u++) {
373 2799
                if (! vbit_test(healthy, u))
374 160
                        continue;
375 2639
                a += vd->weight[u];
376 2639
                if (w < a)
377 1840
                        return (u);
378 799
        }
379 0
        WRONG("");
380
}
381
382
VCL_BACKEND
383 1880
vdir_pick_be(VRT_CTX, struct vdir *vd, double w)
384
{
385
        unsigned u;
386 1880
        VCL_BACKEND be = NULL;
387
388 1880
        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
389 1880
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
390 1880
        vdir_wrlock(vd);
391 1880
        vdir_update_health(ctx, vd);
392 1880
        if (vd->total_weight > 0.0) {
393 1840
                u = vdir_pick_by_weight(vd, w * vd->total_weight);
394 1840
                assert(u < vd->n_backend);
395 1840
                be = vd->backend[u];
396 1840
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
397 1840
        }
398 1880
        vdir_unlock(vd);
399 1880
        return (be);
400
}