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Commit 9891a071 authored by Poul-Henning Kamp's avatar Poul-Henning Kamp
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Split the backend code into two files, the probe code will make it 

more complicated than a single file can carry.

cache_backend_cfg.c now contains the configuration and selection of
backends and directors.

cache_backend.c contains the connection and request management against
backends.



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@2905 d4fa192b-c00b-0410-8231-f00ffab90ce4
parent 9d2652c9
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Showing with 373 additions and 280 deletions
bin/varnishd/Makefile.am
View file @ 9891a071
......@@ -12,6 +12,7 @@ varnishd_SOURCES = \
cache_acceptor_poll.c \
cache_acceptor_kqueue.c \
cache_backend.c \
cache_backend_cfg.c \
cache_ban.c \
cache_center.c \
cache_cli.c \
......
bin/varnishd/cache.h
View file @ 9891a071
......@@ -413,17 +413,19 @@ extern int vca_pipes[2];
/* cache_backend.c */
void VBE_Init(void);
struct vbe_conn *VBE_GetFd(struct sess *sp);
struct vbe_conn *VBE_GetFd(const struct sess *sp);
void VBE_ClosedFd(struct worker *w, struct vbe_conn *vc);
void VBE_RecycleFd(struct worker *w, struct vbe_conn *vc);
struct bereq * VBE_new_bereq(void);
void VBE_free_bereq(struct bereq *bereq);
void VBE_DropRef(struct backend *);
struct backend *VBE_AddBackend(struct cli *cli, const struct vrt_backend *vb);
void VBE_UpdateHealth(const struct sess *sp, const struct vbe_conn *, int);
void VBE_AddHostHeader(struct sess *sp);
void VBE_AddHostHeader(const struct sess *sp);
/* cache_backend_cfg.c */
void VBE_Init(void);
void VBE_DropRef(struct backend *);
void VBE_SelectBackend(struct sess *sp);
struct backend *VBE_AddBackend(struct cli *cli, const struct vrt_backend *vb);
/* cache_ban.c */
int BAN_Add(struct cli *cli, const char *regexp, int hash);
......
bin/varnishd/cache_backend.c
View file @ 9891a071
......@@ -28,43 +28,7 @@
*
* $Id$
*
* This is the central switch-board for backend connections and it is
* slightly complicated by a number of optimizations.
*
* The data structures:
*
* A vrt_backend is a definition of a backend in a VCL program.
*
* A backend is a TCP destination, possibly multi-homed and it has a
* number of associated properties and statistics.
*
* A vbe_conn is an open TCP connection to a backend.
*
* A bereq is a memory carrier for handling a HTTP transaction with
* a backend over a vbe_conn.
*
* A director is a piece of code that selects which backend to use,
* by whatever method or metric it chooses.
*
* The relationships:
*
* Backends and directors get instantiated when VCL's are loaded,
* and this always happen in the CLI thread.
*
* When a VCL tries to instantiate a backend, any existing backend
* with the same identity (== definition in VCL) will be used instead
* so that vbe_conn's can be reused across VCL changes.
*
* Directors disapper with the VCL that created them.
*
* Backends disappear when their reference count drop to zero.
*
* Backends have their host/port name looked up to addrinfo structures
* when they are instantiated, and we just cache that result and cycle
* through the entries (for multihomed backends) on failure only.
* XXX: add cli command to redo lookup.
*
* bereq is sort of a step-child here, we just manage the pool of them.
* Handle backend connections and backend request structures.
*
*/
......@@ -82,29 +46,7 @@
#include "shmlog.h"
#include "cache.h"
#include "vrt.h"
#include "cli_priv.h"
/* Backend indstance */
struct backend {
unsigned magic;
#define BACKEND_MAGIC 0x64c4c7c6
struct vrt_backend vrt[1];
uint32_t hash;
VTAILQ_ENTRY(backend) list;
int refcount;
pthread_mutex_t mtx;
struct addrinfo *ai;
struct addrinfo *last_ai;
VTAILQ_HEAD(, vbe_conn) connlist;
int health;
};
static MTX VBE_mtx;
#include "cache_backend.h"
/*
* List of cached vbe_conns, used if enabled in params/heritage
......@@ -116,17 +58,11 @@ static VTAILQ_HEAD(,vbe_conn) vbe_conns = VTAILQ_HEAD_INITIALIZER(vbe_conns);
*/
static VTAILQ_HEAD(,bereq) bereq_head = VTAILQ_HEAD_INITIALIZER(bereq_head);
/*
* The list of backends is not locked, it is only ever accessed from
* the CLI thread, so there is no need.
*/
static VTAILQ_HEAD(, backend) backends = VTAILQ_HEAD_INITIALIZER(backends);
/*--------------------------------------------------------------------
* Create default Host: header for backend request
*/
void
VBE_AddHostHeader(struct sess *sp)
VBE_AddHostHeader(const struct sess *sp)
{
CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
......@@ -299,7 +235,7 @@ VBE_NewConn(void)
return (vc);
}
static void
void
VBE_ReleaseConn(struct vbe_conn *vc)
{
......@@ -318,52 +254,6 @@ VBE_ReleaseConn(struct vbe_conn *vc)
}
}
/*--------------------------------------------------------------------
* Drop a reference to a backend.
* The last reference must come from the watcher in the CLI thread,
* as only that thread is allowed to clean up the backend list.
*/
static void
VBE_DropRefLocked(struct backend *b)
{
int i;
struct vbe_conn *vbe, *vbe2;
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
assert(b->refcount > 0);
i = --b->refcount;
UNLOCK(&b->mtx);
if (i > 0)
return;
ASSERT_CLI();
VTAILQ_REMOVE(&backends, b, list);
VTAILQ_FOREACH_SAFE(vbe, &b->connlist, list, vbe2) {
VTAILQ_REMOVE(&b->connlist, vbe, list);
if (vbe->fd >= 0)
AZ(close(vbe->fd));
VBE_ReleaseConn(vbe);
}
free(TRUST_ME(b->vrt->ident));
free(TRUST_ME(b->vrt->hostname));
free(TRUST_ME(b->vrt->portname));
b->magic = 0;
free(b);
VSL_stats->n_backend--;
}
void
VBE_DropRef(struct backend *b)
{
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
LOCK(&b->mtx);
VBE_DropRefLocked(b);
}
/*--------------------------------------------------------------------
* Try to get a socket connected to one of the addresses on the list.
* We start from the cached "last good" address and try all items on
......@@ -430,22 +320,8 @@ bes_conn_try(const struct sess *sp, struct backend *bp)
/*--------------------------------------------------------------------*/
void
VBE_SelectBackend(struct sess *sp)
{
struct backend *bp;
CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
CHECK_OBJ_NOTNULL(sp->director, DIRECTOR_MAGIC);
bp = sp->director->choose(sp);
CHECK_OBJ_NOTNULL(bp, BACKEND_MAGIC);
sp->backend = bp;
}
/*--------------------------------------------------------------------*/
struct vbe_conn *
VBE_GetFd(struct sess *sp)
VBE_GetFd(const struct sess *sp)
{
struct backend *bp;
struct vbe_conn *vc;
......@@ -560,149 +436,3 @@ VBE_UpdateHealth(const struct sess *sp, const struct vbe_conn *vc, int a)
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
#endif
}
/*--------------------------------------------------------------------
* DNS lookup of backend host/port
*/
static void
vbe_dns_lookup(struct cli *cli, struct backend *bp)
{
int error;
struct addrinfo *res, hint, *old;
CHECK_OBJ_NOTNULL(bp, BACKEND_MAGIC);
memset(&hint, 0, sizeof hint);
hint.ai_family = PF_UNSPEC;
hint.ai_socktype = SOCK_STREAM;
res = NULL;
error = getaddrinfo(bp->vrt->hostname, bp->vrt->portname,
&hint, &res);
if (error) {
if (res != NULL)
freeaddrinfo(res);
/*
* We cannot point to the source code any more, it may
* be long gone from memory. We already checked over in
* the VCL compiler, so this is only relevant for refreshes.
* XXX: which we do when exactly ?
*/
cli_out(cli, "DNS(/hosts) lookup failed for (%s/%s): %s",
bp->vrt->hostname, bp->vrt->portname, gai_strerror(error));
return;
}
LOCK(&bp->mtx);
old = bp->ai;
bp->ai = res;
bp->last_ai = res;
UNLOCK(&bp->mtx);
if (old != NULL)
freeaddrinfo(old);
}
/*--------------------------------------------------------------------
* Add a backend/director instance when loading a VCL.
* If an existing backend is matched, grab a refcount and return.
* Else create a new backend structure with reference initialized to one.
*/
struct backend *
VBE_AddBackend(struct cli *cli, const struct vrt_backend *vb)
{
struct backend *b;
uint32_t u;
AN(vb->hostname);
AN(vb->portname);
AN(vb->ident);
(void)cli;
ASSERT_CLI();
u = crc32_l(vb->ident, strlen(vb->ident));
VTAILQ_FOREACH(b, &backends, list) {
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
if (u != b->hash)
continue;
if (strcmp(b->vrt->ident, vb->ident))
continue;
b->refcount++;
return (b);
}
ALLOC_OBJ(b, BACKEND_MAGIC);
XXXAN(b);
b->magic = BACKEND_MAGIC;
VTAILQ_INIT(&b->connlist);
b->hash = u;
/*
* This backend may live longer than the VCL that instantiated it
* so we cannot simply reference the VCL's copy of things.
*/
REPLACE(b->vrt->ident, vb->ident);
REPLACE(b->vrt->hostname, vb->hostname);
REPLACE(b->vrt->portname, vb->portname);
REPLACE(b->vrt->vcl_name, vb->vcl_name);
b->vrt->connect_timeout = vb->connect_timeout;
MTX_INIT(&b->mtx);
b->refcount = 1;
vbe_dns_lookup(cli, b);
VTAILQ_INSERT_TAIL(&backends, b, list);
VSL_stats->n_backend++;
return (b);
}
/*--------------------------------------------------------------------*/
void
VRT_fini_dir(struct cli *cli, struct director *b)
{
(void)cli;
ASSERT_CLI();
CHECK_OBJ_NOTNULL(b, DIRECTOR_MAGIC);
b->fini(b);
}
/*--------------------------------------------------------------------*/
static void
cli_debug_backend(struct cli *cli, const char * const *av, void *priv)
{
struct backend *b;
(void)av;
(void)priv;
ASSERT_CLI();
VTAILQ_FOREACH(b, &backends, list) {
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
cli_out(cli, "%p %s/%s/%s %d\n",
b,
b->vrt->vcl_name,
b->vrt->hostname,
b->vrt->portname,
b->refcount);
}
}
static struct cli_proto debug_cmds[] = {
{ "debug.backend", "debug.backend",
"\tExamine Backend internals\n", 0, 0, cli_debug_backend },
{ NULL }
};
/*--------------------------------------------------------------------*/
void
VBE_Init(void)
{
MTX_INIT(&VBE_mtx);
CLI_AddFuncs(DEBUG_CLI, debug_cmds);
}
bin/varnishd/cache_backend.h 0 → 100644
View file @ 9891a071
/*-
* Copyright (c) 2006 Verdens Gang AS
* Copyright (c) 2006-2008 Linpro AS
* All rights reserved.
*
* Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
*
* 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.
*
* $Id$
*
* This is the central switch-board for backend connections and it is
* slightly complicated by a number of optimizations.
*
* The data structures:
*
* A vrt_backend is a definition of a backend in a VCL program.
*
* A backend is a TCP destination, possibly multi-homed and it has a
* number of associated properties and statistics.
*
* A vbe_conn is an open TCP connection to a backend.
*
* A bereq is a memory carrier for handling a HTTP transaction with
* a backend over a vbe_conn.
*
* A director is a piece of code that selects which backend to use,
* by whatever method or metric it chooses.
*
* The relationships:
*
* Backends and directors get instantiated when VCL's are loaded,
* and this always happen in the CLI thread.
*
* When a VCL tries to instantiate a backend, any existing backend
* with the same identity (== definition in VCL) will be used instead
* so that vbe_conn's can be reused across VCL changes.
*
* Directors disapper with the VCL that created them.
*
* Backends disappear when their reference count drop to zero.
*
* Backends have their host/port name looked up to addrinfo structures
* when they are instantiated, and we just cache that result and cycle
* through the entries (for multihomed backends) on failure only.
* XXX: add cli command to redo lookup.
*
* bereq is sort of a step-child here, we just manage the pool of them.
*
*/
/* Backend indstance */
struct backend {
unsigned magic;
#define BACKEND_MAGIC 0x64c4c7c6
struct vrt_backend vrt[1];
uint32_t hash;
VTAILQ_ENTRY(backend) list;
int refcount;
pthread_mutex_t mtx;
struct addrinfo *ai;
struct addrinfo *last_ai;
VTAILQ_HEAD(, vbe_conn) connlist;
int health;
};
/* cache_backend_cfg.c */
extern MTX VBE_mtx;
void VBE_DropRefLocked(struct backend *b);
/* cache_backend.c */
void VBE_ReleaseConn(struct vbe_conn *vc);
bin/varnishd/cache_backend_cfg.c 0 → 100644
View file @ 9891a071
/*-
* Copyright (c) 2006 Verdens Gang AS
* Copyright (c) 2006-2008 Linpro AS
* All rights reserved.
*
* Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
*
* 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.
*
* $Id$
*
* Handle configuration of backends from VCL programs.
*
*/
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <poll.h>
#include <sys/socket.h>
#include <netdb.h>
#include "shmlog.h"
#include "cache.h"
#include "vrt.h"
#include "cache_backend.h"
#include "cli_priv.h"
MTX VBE_mtx;
/*
* The list of backends is not locked, it is only ever accessed from
* the CLI thread, so there is no need.
*/
static VTAILQ_HEAD(, backend) backends = VTAILQ_HEAD_INITIALIZER(backends);
/*--------------------------------------------------------------------*/
void
VBE_SelectBackend(struct sess *sp)
{
struct backend *bp;
CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
CHECK_OBJ_NOTNULL(sp->director, DIRECTOR_MAGIC);
bp = sp->director->choose(sp);
CHECK_OBJ_NOTNULL(bp, BACKEND_MAGIC);
sp->backend = bp;
}
/*--------------------------------------------------------------------
* Drop a reference to a backend.
* The last reference must come from the watcher in the CLI thread,
* as only that thread is allowed to clean up the backend list.
*/
void
VBE_DropRefLocked(struct backend *b)
{
int i;
struct vbe_conn *vbe, *vbe2;
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
assert(b->refcount > 0);
i = --b->refcount;
UNLOCK(&b->mtx);
if (i > 0)
return;
ASSERT_CLI();
VTAILQ_REMOVE(&backends, b, list);
VTAILQ_FOREACH_SAFE(vbe, &b->connlist, list, vbe2) {
VTAILQ_REMOVE(&b->connlist, vbe, list);
if (vbe->fd >= 0)
AZ(close(vbe->fd));
VBE_ReleaseConn(vbe);
}
free(TRUST_ME(b->vrt->ident));
free(TRUST_ME(b->vrt->hostname));
free(TRUST_ME(b->vrt->portname));
b->magic = 0;
free(b);
VSL_stats->n_backend--;
}
void
VBE_DropRef(struct backend *b)
{
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
LOCK(&b->mtx);
VBE_DropRefLocked(b);
}
/*--------------------------------------------------------------------
* DNS lookup of backend host/port
*/
static void
vbe_dns_lookup(const struct cli *cli, struct backend *bp)
{
int error;
struct addrinfo *res, hint, *old;
CHECK_OBJ_NOTNULL(bp, BACKEND_MAGIC);
memset(&hint, 0, sizeof hint);
hint.ai_family = PF_UNSPEC;
hint.ai_socktype = SOCK_STREAM;
res = NULL;
error = getaddrinfo(bp->vrt->hostname, bp->vrt->portname,
&hint, &res);
if (error) {
if (res != NULL)
freeaddrinfo(res);
/*
* We cannot point to the source code any more, it may
* be long gone from memory. We already checked over in
* the VCL compiler, so this is only relevant for refreshes.
* XXX: which we do when exactly ?
*/
cli_out(cli, "DNS(/hosts) lookup failed for (%s/%s): %s",
bp->vrt->hostname, bp->vrt->portname, gai_strerror(error));
return;
}
LOCK(&bp->mtx);
old = bp->ai;
bp->ai = res;
bp->last_ai = res;
UNLOCK(&bp->mtx);
if (old != NULL)
freeaddrinfo(old);
}
/*--------------------------------------------------------------------
* Add a backend/director instance when loading a VCL.
* If an existing backend is matched, grab a refcount and return.
* Else create a new backend structure with reference initialized to one.
*/
struct backend *
VBE_AddBackend(struct cli *cli, const struct vrt_backend *vb)
{
struct backend *b;
uint32_t u;
AN(vb->hostname);
AN(vb->portname);
AN(vb->ident);
(void)cli;
ASSERT_CLI();
u = crc32_l(vb->ident, strlen(vb->ident));
VTAILQ_FOREACH(b, &backends, list) {
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
if (u != b->hash)
continue;
if (strcmp(b->vrt->ident, vb->ident))
continue;
b->refcount++;
return (b);
}
ALLOC_OBJ(b, BACKEND_MAGIC);
XXXAN(b);
b->magic = BACKEND_MAGIC;
VTAILQ_INIT(&b->connlist);
b->hash = u;
/*
* This backend may live longer than the VCL that instantiated it
* so we cannot simply reference the VCL's copy of things.
*/
REPLACE(b->vrt->ident, vb->ident);
REPLACE(b->vrt->hostname, vb->hostname);
REPLACE(b->vrt->portname, vb->portname);
REPLACE(b->vrt->vcl_name, vb->vcl_name);
b->vrt->connect_timeout = vb->connect_timeout;
MTX_INIT(&b->mtx);
b->refcount = 1;
vbe_dns_lookup(cli, b);
VTAILQ_INSERT_TAIL(&backends, b, list);
VSL_stats->n_backend++;
return (b);
}
/*--------------------------------------------------------------------*/
void
VRT_fini_dir(struct cli *cli, struct director *b)
{
(void)cli;
ASSERT_CLI();
CHECK_OBJ_NOTNULL(b, DIRECTOR_MAGIC);
b->fini(b);
}
/*--------------------------------------------------------------------*/
static void
cli_debug_backend(struct cli *cli, const char * const *av, void *priv)
{
struct backend *b;
(void)av;
(void)priv;
ASSERT_CLI();
VTAILQ_FOREACH(b, &backends, list) {
CHECK_OBJ_NOTNULL(b, BACKEND_MAGIC);
cli_out(cli, "%p %s/%s/%s %d\n",
b,
b->vrt->vcl_name,
b->vrt->hostname,
b->vrt->portname,
b->refcount);
}
}
static struct cli_proto debug_cmds[] = {
{ "debug.backend", "debug.backend",
"\tExamine Backend internals\n", 0, 0, cli_debug_backend },
{ NULL }
};
/*--------------------------------------------------------------------*/
void
VBE_Init(void)
{
MTX_INIT(&VBE_mtx);
CLI_AddFuncs(DEBUG_CLI, debug_cmds);
}
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