GCOV - Varnish Cache


/*-
 * Copyright (c) 2013-2015 Varnish Software AS
 * Copyright 2019 UPLEX - Nils Goroll Systemoptimierung
 * All rights reserved.
 *
 * Author: Poul-Henning Kamp <phk@FreeBSD.org>
 * Author: Nils Goroll <nils.goroll@uplex.de>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 "config.h"

#include <stdlib.h>
#include <stdio.h>

#include "cache/cache.h"

#include "vbm.h"
#include "vcl.h"
#include "vsb.h"

#include "vcc_directors_if.h"

#include "vmod_directors.h"

VCL_BACKEND
VPFX(lookup)(VRT_CTX, VCL_STRING name)
{
        if ((ctx->method & VCL_MET_TASK_H) == 0) {
                VRT_fail(ctx,
                    "lookup() may only be called from vcl_init / vcl_fini");
                return (NULL);
        }

        return (VRT_LookupDirector(ctx, name));
}

static void
vdir_expand(struct vdir *vd, unsigned n)
{
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);

        vd->backend = realloc(vd->backend, n * sizeof *vd->backend);
        AN(vd->backend);
        vd->weight = realloc(vd->weight, n * sizeof *vd->weight);
        AN(vd->weight);
        if (n > vd->healthy->nbits)
                vbit_expand(vd->healthy, n);
        AN(vd->healthy);
        vd->l_backend = n;
}

void
vdir_new(VRT_CTX, struct vdir **vdp, const char *vcl_name,
    const struct vdi_methods *m, void *priv)
{
        struct vdir *vd;

        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
        CHECK_OBJ_NOTNULL(m, VDI_METHODS_MAGIC);
        AN(vcl_name);
        AN(vdp);
        AZ(*vdp);
        ALLOC_OBJ(vd, VDIR_MAGIC);
        AN(vd);
        *vdp = vd;
        AZ(pthread_rwlock_init(&vd->mtx, NULL));
        vd->dir = VRT_AddDirector(ctx, m, priv, "%s", vcl_name);
        vd->healthy = vbit_new(8);
        AN(vd->healthy);
}

void
vdir_delete(struct vdir **vdp)
{
        struct vdir *vd;
        unsigned u;

        TAKE_OBJ_NOTNULL(vd, vdp, VDIR_MAGIC);

        AZ(vd->dir);
        for (u = 0; u < vd->n_backend; u++)
                VRT_Assign_Backend(&vd->backend[u], NULL);
        free(vd->backend);
        free(vd->weight);
        AZ(pthread_rwlock_destroy(&vd->mtx));
        vbit_destroy(vd->healthy);
        FREE_OBJ(vd);
}

void
vdir_rdlock(struct vdir *vd)
{
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
        AZ(pthread_rwlock_rdlock(&vd->mtx));
}

void
vdir_wrlock(struct vdir *vd)
{
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
        AZ(pthread_rwlock_wrlock(&vd->mtx));
}

void
vdir_unlock(struct vdir *vd)
{
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
        AZ(pthread_rwlock_unlock(&vd->mtx));
}


void
vdir_add_backend(VRT_CTX, struct vdir *vd, VCL_BACKEND be, double weight)
{
        unsigned u;

        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
        if (be == NULL) {
                VRT_fail(ctx, "%s: None backend cannot be added",
                    VRT_BACKEND_string(vd->dir));
                return;
        }
        AN(be);
        vdir_wrlock(vd);
        if (vd->n_backend >= vd->l_backend)
                vdir_expand(vd, vd->l_backend + 16);
        assert(vd->n_backend < vd->l_backend);
        u = vd->n_backend++;
        vd->backend[u] = NULL;
        VRT_Assign_Backend(&vd->backend[u], be);
        vd->weight[u] = weight;
        vdir_unlock(vd);
}

void
vdir_remove_backend(VRT_CTX, struct vdir *vd, VCL_BACKEND be, unsigned *cur)
{
        unsigned u, n;

        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
        if (be == NULL) {
                VRT_fail(ctx, "%s: None backend cannot be removed",
                    VRT_BACKEND_string(vd->dir));
                return;
        }
        CHECK_OBJ(be, DIRECTOR_MAGIC);
        vdir_wrlock(vd);
        for (u = 0; u < vd->n_backend; u++)
                if (vd->backend[u] == be)
                        break;
        if (u == vd->n_backend) {
                vdir_unlock(vd);
                return;
        }
        VRT_Assign_Backend(&vd->backend[u], NULL);
        n = (vd->n_backend - u) - 1;
        memmove(&vd->backend[u], &vd->backend[u+1], n * sizeof(vd->backend[0]));
        memmove(&vd->weight[u], &vd->weight[u+1], n * sizeof(vd->weight[0]));
        vd->n_backend--;

        if (cur) {
                assert(*cur <= vd->n_backend);
                if (u < *cur)
                        (*cur)--;
                else if (*cur == vd->n_backend)
                        *cur = 0;
        }
        vdir_unlock(vd);
}

VCL_BOOL
vdir_any_healthy(VRT_CTX, struct vdir *vd, VCL_TIME *changed)
{
        unsigned retval = 0;
        VCL_BACKEND be;
        unsigned u;
        vtim_real c;

        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
        vdir_rdlock(vd);
        if (changed != NULL)
                *changed = 0;
        for (u = 0; u < vd->n_backend; u++) {
                be = vd->backend[u];
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
                retval = VRT_Healthy(ctx, be, &c);
                if (changed != NULL && c > *changed)
                        *changed = c;
                if (retval)
                        break;
        }
        vdir_unlock(vd);
        return (retval);
}

void
vdir_list(VRT_CTX, struct vdir *vd, struct vsb *vsb, int pflag, int jflag,
    int weight)
{
        VCL_BACKEND be;
        VCL_BOOL h;
        unsigned u, nh;
        double w;

        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);

        if (pflag) {
                if (jflag) {
                        VSB_cat(vsb, "{\n");
                        VSB_indent(vsb, 2);
                        if (weight)
                                VSB_printf(vsb, "\"total_weight\": %f,\n",
                                    vd->total_weight);
                        VSB_cat(vsb, "\"backends\": {\n");
                        VSB_indent(vsb, 2);
                } else {
                        VSB_cat(vsb, "\n\n\tBackend\tWeight\tHealth\n");
                }
        }

        vdir_rdlock(vd);
        vdir_update_health(ctx, vd);
        for (u = 0; pflag && u < vd->n_backend; u++) {
                be = vd->backend[u];
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);

                h = vbit_test(vd->healthy, u);

                w = h ? vd->weight[u] : 0.0;

                if (jflag) {
                        if (u)
                                VSB_cat(vsb, ",\n");
                        VSB_printf(vsb, "\"%s\": {\n", be->vcl_name);
                        VSB_indent(vsb, 2);

                        if (weight)
                                VSB_printf(vsb, "\"weight\": %f,\n", w);

                        if (h)
                                VSB_cat(vsb, "\"health\": \"healthy\"\n");
                        else
                                VSB_cat(vsb, "\"health\": \"sick\"\n");

                        VSB_indent(vsb, -2);
                        VSB_cat(vsb, "}");
                } else {
                        VSB_cat(vsb, "\t");
                        VSB_cat(vsb, be->vcl_name);
                        if (weight)
                                VSB_printf(vsb, "\t%6.2f%%\t",
                                    100 * w / vd->total_weight);
                        else
                                VSB_cat(vsb, "\t-\t");
                        VSB_cat(vsb, h ? "healthy" : "sick");
                        VSB_cat(vsb, "\n");
                }
        }
        nh = vd->n_healthy;
        u = vd->n_backend;
        vdir_unlock(vd);

        if (jflag && (pflag)) {
                VSB_cat(vsb, "\n");
                VSB_indent(vsb, -2);
                VSB_cat(vsb, "}\n");
                VSB_indent(vsb, -2);
                VSB_cat(vsb, "},\n");
        }

        if (pflag)
                return;

        if (jflag)
                VSB_printf(vsb, "[%u, %u, \"%s\"]", nh, u,
                    nh ? "healthy" : "sick");
        else
                VSB_printf(vsb, "%u/%u\t%s", nh, u, nh ? "healthy" : "sick");
}

/*
 * iterate backends and update
 * - healthy bitmap
 * - number of healthy backends
 * - total_weight
 * - last change time of the VCL_BACKEND
 *
 * must be called under the vdir lock (read or write).
 *
 * A write lock is required if consistency between the individual attributes is
 * a must, e.g. when total_weight is required to be the exact sum of the weights
 *
 * The read lock is safe because add_backend expands the healthy bitmap and all
 * other members are atomic and may be used if consistency is not required.
 */
void
vdir_update_health(VRT_CTX, struct vdir *vd)
{
        VCL_TIME c, changed = 0;
        VCL_BOOL h;
        VCL_BACKEND be;
        unsigned u, nh = 0;
        double tw = 0.0;
        struct vbitmap *healthy;

        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
        healthy = vd->healthy;
        for (u = 0; u < vd->n_backend; u++) {
                be = vd->backend[u];
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
                c = 0;
                h = VRT_Healthy(ctx, vd->backend[u], &c);
                if (h) {
                        nh++;
                        tw += vd->weight[u];
                }
                if (c > changed)
                        changed = c;
                if (h != vbit_test(healthy, u)) {
                        if (h)
                                vbit_set(healthy, u);
                        else
                                vbit_clr(healthy, u);
                }
        }
        VRT_SetChanged(vd->dir, changed);
        vd->total_weight = tw;
        vd->n_healthy = nh;
}

static unsigned
vdir_pick_by_weight(const struct vdir *vd, double w)
{
        const struct vbitmap *healthy = vd->healthy;
        double a = 0.0;
        unsigned u;

        AN(healthy);
        for (u = 0; u < vd->n_backend; u++) {
                if (! vbit_test(healthy, u))
                        continue;
                a += vd->weight[u];
                if (w < a)
                        return (u);
        }
        WRONG("");
}

VCL_BACKEND
vdir_pick_be(VRT_CTX, struct vdir *vd, double w)
{
        unsigned u;
        VCL_BACKEND be = NULL;

        CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
        CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
        vdir_wrlock(vd);
        vdir_update_health(ctx, vd);
        if (vd->total_weight > 0.0) {
                u = vdir_pick_by_weight(vd, w * vd->total_weight);
                assert(u < vd->n_backend);
                be = vd->backend[u];
                CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
        }
        vdir_unlock(vd);
        return (be);
}

		varnish-cache/vmod/vmod_directors.c
0		/*-
1		* Copyright (c) 2013-2015 Varnish Software AS
2		* Copyright 2019 UPLEX - Nils Goroll Systemoptimierung
3		* All rights reserved.
4		*
5		* Author: Poul-Henning Kamp <phk@FreeBSD.org>
6		* Author: Nils Goroll <nils.goroll@uplex.de>
7		*
8		* SPDX-License-Identifier: BSD-2-Clause
9		*
10		* Redistribution and use in source and binary forms, with or without
11		* modification, are permitted provided that the following conditions
12		* are met:
13		* 1. Redistributions of source code must retain the above copyright
14		* notice, this list of conditions and the following disclaimer.
15		* 2. Redistributions in binary form must reproduce the above copyright
16		* notice, this list of conditions and the following disclaimer in the
17		* documentation and/or other materials provided with the distribution.
18		*
19		* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20		* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21		* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22		* ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
23		* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24		* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25		* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26		* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27		* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28		* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29		* SUCH DAMAGE.
30		*/
31
32		#include "config.h"
33
34		#include <stdlib.h>
35		#include <stdio.h>
36
37		#include "cache/cache.h"
38
39		#include "vbm.h"
40		#include "vcl.h"
41		#include "vsb.h"
42
43		#include "vcc_directors_if.h"
44
45		#include "vmod_directors.h"
46
47		VCL_BACKEND
48	80	VPFX(lookup)(VRT_CTX, VCL_STRING name)
49		{
50	80	if ((ctx->method & VCL_MET_TASK_H) == 0) {
51	40	VRT_fail(ctx,
52		"lookup() may only be called from vcl_init / vcl_fini");
53	40	return (NULL);
54		}
55
56	40	return (VRT_LookupDirector(ctx, name));
57	80	}
58
59		static void
60	1200	vdir_expand(struct vdir *vd, unsigned n)
61		{
62	1200	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
63
64	1200	vd->backend = realloc(vd->backend, n * sizeof *vd->backend);
65	1200	AN(vd->backend);
66	1200	vd->weight = realloc(vd->weight, n * sizeof *vd->weight);
67	1200	AN(vd->weight);
68	1200	if (n > vd->healthy->nbits)
69	0	vbit_expand(vd->healthy, n);
70	1200	AN(vd->healthy);
71	1200	vd->l_backend = n;
72	1200	}
73
74		void
75	1320	vdir_new(VRT_CTX, struct vdir *vdp, const char vcl_name,
76		const struct vdi_methods m, void priv)
77		{
78		struct vdir *vd;
79
80	1320	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
81	1320	CHECK_OBJ_NOTNULL(m, VDI_METHODS_MAGIC);
82	1320	AN(vcl_name);
83	1320	AN(vdp);
84	1320	AZ(*vdp);
85	1320	ALLOC_OBJ(vd, VDIR_MAGIC);
86	1320	AN(vd);
87	1320	*vdp = vd;
88	1320	AZ(pthread_rwlock_init(&vd->mtx, NULL));
89	1320	vd->dir = VRT_AddDirector(ctx, m, priv, "%s", vcl_name);
90	1320	vd->healthy = vbit_new(8);
91	1320	AN(vd->healthy);
92	1320	}
93
94		void
95	240	vdir_delete(struct vdir **vdp)
96		{
97		struct vdir *vd;
98		unsigned u;
99
100	240	TAKE_OBJ_NOTNULL(vd, vdp, VDIR_MAGIC);
101
102	240	AZ(vd->dir);
103	480	for (u = 0; u < vd->n_backend; u++)
104	240	VRT_Assign_Backend(&vd->backend[u], NULL);
105	240	free(vd->backend);
106	240	free(vd->weight);
107	240	AZ(pthread_rwlock_destroy(&vd->mtx));
108	240	vbit_destroy(vd->healthy);
109	240	FREE_OBJ(vd);
110	240	}
111
112		void
113	6240	vdir_rdlock(struct vdir *vd)
114		{
115	6240	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
116	6240	AZ(pthread_rwlock_rdlock(&vd->mtx));
117	6240	}
118
119		void
120	6360	vdir_wrlock(struct vdir *vd)
121		{
122	6360	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
123	6360	AZ(pthread_rwlock_wrlock(&vd->mtx));
124	6360	}
125
126		void
127	12600	vdir_unlock(struct vdir *vd)
128		{
129	12600	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
130	12600	AZ(pthread_rwlock_unlock(&vd->mtx));
131	12600	}
132
133
134		void
135	3200	vdir_add_backend(VRT_CTX, struct vdir *vd, VCL_BACKEND be, double weight)
136		{
137		unsigned u;
138
139	3200	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
140	3200	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
141	3200	if (be == NULL) {
142	240	VRT_fail(ctx, "%s: None backend cannot be added",
143	120	VRT_BACKEND_string(vd->dir));
144	120	return;
145		}
146	3080	AN(be);
147	3080	vdir_wrlock(vd);
148	3080	if (vd->n_backend >= vd->l_backend)
149	1200	vdir_expand(vd, vd->l_backend + 16);
150	3080	assert(vd->n_backend < vd->l_backend);
151	3080	u = vd->n_backend++;
152	3080	vd->backend[u] = NULL;
153	3080	VRT_Assign_Backend(&vd->backend[u], be);
154	3080	vd->weight[u] = weight;
155	3080	vdir_unlock(vd);
156	3200	}
157
158		void
159	480	vdir_remove_backend(VRT_CTX, struct vdir vd, VCL_BACKEND be, unsigned cur)
160		{
161		unsigned u, n;
162
163	480	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
164	480	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
165	480	if (be == NULL) {
166	0	VRT_fail(ctx, "%s: None backend cannot be removed",
167	0	VRT_BACKEND_string(vd->dir));
168	0	return;
169		}
170	480	CHECK_OBJ(be, DIRECTOR_MAGIC);
171	480	vdir_wrlock(vd);
172	680	for (u = 0; u < vd->n_backend; u++)
173	680	if (vd->backend[u] == be)
174	480	break;
175	480	if (u == vd->n_backend) {
176	0	vdir_unlock(vd);
177	0	return;
178		}
179	480	VRT_Assign_Backend(&vd->backend[u], NULL);
180	480	n = (vd->n_backend - u) - 1;
181	480	memmove(&vd->backend[u], &vd->backend[u+1], n * sizeof(vd->backend[0]));
182	480	memmove(&vd->weight[u], &vd->weight[u+1], n * sizeof(vd->weight[0]));
183	480	vd->n_backend--;
184
185	480	if (cur) {
186	160	assert(*cur <= vd->n_backend);
187	160	if (u < *cur)
188	40	(*cur)--;
189	120	else if (*cur == vd->n_backend)
190	40	*cur = 0;
191	160	}
192	480	vdir_unlock(vd);
193	480	}
194
195		VCL_BOOL
196	1960	vdir_any_healthy(VRT_CTX, struct vdir vd, VCL_TIME changed)
197		{
198	1960	unsigned retval = 0;
199		VCL_BACKEND be;
200		unsigned u;
201		vtim_real c;
202
203	1960	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
204	1960	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
205	1960	vdir_rdlock(vd);
206	1960	if (changed != NULL)
207	400	*changed = 0;
208	2800	for (u = 0; u < vd->n_backend; u++) {
209	2520	be = vd->backend[u];
210	2520	CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
211	2520	retval = VRT_Healthy(ctx, be, &c);
212	2520	if (changed != NULL && c > *changed)
213	520	*changed = c;
214	2520	if (retval)
215	1680	break;
216	840	}
217	1960	vdir_unlock(vd);
218	1960	return (retval);
219		}
220
221		void
222	2040	vdir_list(VRT_CTX, struct vdir vd, struct vsb vsb, int pflag, int jflag,
223		int weight)
224		{
225		VCL_BACKEND be;
226		VCL_BOOL h;
227		unsigned u, nh;
228		double w;
229
230	2040	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
231	2040	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
232
233	2040	if (pflag) {
234	320	if (jflag) {
235	160	VSB_cat(vsb, "{\n");
236	160	VSB_indent(vsb, 2);
237	160	if (weight)
238	80	VSB_printf(vsb, "\"total_weight\": %f,\n",
239	40	vd->total_weight);
240	160	VSB_cat(vsb, "\"backends\": {\n");
241	160	VSB_indent(vsb, 2);
242	160	} else {
243	160	VSB_cat(vsb, "\n\n\tBackend\tWeight\tHealth\n");
244		}
245	320	}
246
247	2040	vdir_rdlock(vd);
248	2040	vdir_update_health(ctx, vd);
249	2920	for (u = 0; pflag && u < vd->n_backend; u++) {
250	880	be = vd->backend[u];
251	880	CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
252
253	880	h = vbit_test(vd->healthy, u);
254
255	880	w = h ? vd->weight[u] : 0.0;
256
257	880	if (jflag) {
258	440	if (u)
259	280	VSB_cat(vsb, ",\n");
260	440	VSB_printf(vsb, "\"%s\": {\n", be->vcl_name);
261	440	VSB_indent(vsb, 2);
262
263	440	if (weight)
264	160	VSB_printf(vsb, "\"weight\": %f,\n", w);
265
266	440	if (h)
267	320	VSB_cat(vsb, "\"health\": \"healthy\"\n");
268		else
269	120	VSB_cat(vsb, "\"health\": \"sick\"\n");
270
271	440	VSB_indent(vsb, -2);
272	440	VSB_cat(vsb, "}");
273	440	} else {
274	440	VSB_cat(vsb, "\t");
275	440	VSB_cat(vsb, be->vcl_name);
276	440	if (weight)
277	320	VSB_printf(vsb, "\t%6.2f%%\t",
278	160	100 * w / vd->total_weight);
279		else
280	280	VSB_cat(vsb, "\t-\t");
281	440	VSB_cat(vsb, h ? "healthy" : "sick");
282	440	VSB_cat(vsb, "\n");
283		}
284	880	}
285	2040	nh = vd->n_healthy;
286	2040	u = vd->n_backend;
287	2040	vdir_unlock(vd);
288
289	2040	if (jflag && (pflag)) {
290	160	VSB_cat(vsb, "\n");
291	160	VSB_indent(vsb, -2);
292	160	VSB_cat(vsb, "}\n");
293	160	VSB_indent(vsb, -2);
294	160	VSB_cat(vsb, "},\n");
295	160	}
296
297	2040	if (pflag)
298	320	return;
299
300	1720	if (jflag)
301	800	VSB_printf(vsb, "[%u, %u, \"%s\"]", nh, u,
302	400	nh ? "healthy" : "sick");
303		else
304	1320	VSB_printf(vsb, "%u/%u\t%s", nh, u, nh ? "healthy" : "sick");
305	2040	}
306
307		/*
308		* iterate backends and update
309		* - healthy bitmap
310		* - number of healthy backends
311		* - total_weight
312		* - last change time of the VCL_BACKEND
313		*
314		* must be called under the vdir lock (read or write).
315		*
316		* A write lock is required if consistency between the individual attributes is
317		* a must, e.g. when total_weight is required to be the exact sum of the weights
318		*
319		* The read lock is safe because add_backend expands the healthy bitmap and all
320		* other members are atomic and may be used if consistency is not required.
321		*/
322		void
323	4440	vdir_update_health(VRT_CTX, struct vdir *vd)
324		{
325	4440	VCL_TIME c, changed = 0;
326		VCL_BOOL h;
327		VCL_BACKEND be;
328	4440	unsigned u, nh = 0;
329	4440	double tw = 0.0;
330		struct vbitmap *healthy;
331
332	4440	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
333	4440	healthy = vd->healthy;
334	14760	for (u = 0; u < vd->n_backend; u++) {
335	10320	be = vd->backend[u];
336	10320	CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
337	10320	c = 0;
338	10320	h = VRT_Healthy(ctx, vd->backend[u], &c);
339	10320	if (h) {
340	7960	nh++;
341	7960	tw += vd->weight[u];
342	7960	}
343	10320	if (c > changed)
344	9920	changed = c;
345	10320	if (h != vbit_test(healthy, u)) {
346	5200	if (h)
347	5120	vbit_set(healthy, u);
348		else
349	80	vbit_clr(healthy, u);
350	5200	}
351	10320	}
352	4440	VRT_SetChanged(vd->dir, changed);
353	4440	vd->total_weight = tw;
354	4440	vd->n_healthy = nh;
355	4440	}
356
357		static unsigned
358	1840	vdir_pick_by_weight(const struct vdir *vd, double w)
359		{
360	1840	const struct vbitmap *healthy = vd->healthy;
361	1840	double a = 0.0;
362		unsigned u;
363
364	1840	AN(healthy);
365	2799	for (u = 0; u < vd->n_backend; u++) {
366	2799	if (! vbit_test(healthy, u))
367	160	continue;
368	2639	a += vd->weight[u];
369	2639	if (w < a)
370	1840	return (u);
371	799	}
372	0	WRONG("");
373		}
374
375		VCL_BACKEND
376	1880	vdir_pick_be(VRT_CTX, struct vdir *vd, double w)
377		{
378		unsigned u;
379	1880	VCL_BACKEND be = NULL;
380
381	1880	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
382	1880	CHECK_OBJ_NOTNULL(vd, VDIR_MAGIC);
383	1880	vdir_wrlock(vd);
384	1880	vdir_update_health(ctx, vd);
385	1880	if (vd->total_weight > 0.0) {
386	1840	u = vdir_pick_by_weight(vd, w * vd->total_weight);
387	1840	assert(u < vd->n_backend);
388	1840	be = vd->backend[u];
389	1840	CHECK_OBJ_NOTNULL(be, DIRECTOR_MAGIC);
390	1840	}
391	1880	vdir_unlock(vd);
392	1880	return (be);
393		}