blob: 6f169c8f6ab500f135e5844d2f4040cee8b967e8 [file] [log] [blame]
/*
* Copyright (C) Nginx, Inc.
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>
typedef struct {
ngx_http_upstream_rr_peer_t *peer;
ngx_uint_t range;
} ngx_http_upstream_random_range_t;
typedef struct {
ngx_uint_t two;
ngx_http_upstream_random_range_t *ranges;
} ngx_http_upstream_random_srv_conf_t;
typedef struct {
/* the round robin data must be first */
ngx_http_upstream_rr_peer_data_t rrp;
ngx_http_upstream_random_srv_conf_t *conf;
u_char tries;
} ngx_http_upstream_random_peer_data_t;
static ngx_int_t ngx_http_upstream_init_random(ngx_conf_t *cf,
ngx_http_upstream_srv_conf_t *us);
static ngx_int_t ngx_http_upstream_update_random(ngx_pool_t *pool,
ngx_http_upstream_srv_conf_t *us);
static ngx_int_t ngx_http_upstream_init_random_peer(ngx_http_request_t *r,
ngx_http_upstream_srv_conf_t *us);
static ngx_int_t ngx_http_upstream_get_random_peer(ngx_peer_connection_t *pc,
void *data);
static ngx_int_t ngx_http_upstream_get_random2_peer(ngx_peer_connection_t *pc,
void *data);
static ngx_uint_t ngx_http_upstream_peek_random_peer(
ngx_http_upstream_rr_peers_t *peers,
ngx_http_upstream_random_peer_data_t *rp);
static void *ngx_http_upstream_random_create_conf(ngx_conf_t *cf);
static char *ngx_http_upstream_random(ngx_conf_t *cf, ngx_command_t *cmd,
void *conf);
static ngx_command_t ngx_http_upstream_random_commands[] = {
{ ngx_string("random"),
NGX_HTTP_UPS_CONF|NGX_CONF_NOARGS|NGX_CONF_TAKE12,
ngx_http_upstream_random,
NGX_HTTP_SRV_CONF_OFFSET,
0,
NULL },
ngx_null_command
};
static ngx_http_module_t ngx_http_upstream_random_module_ctx = {
NULL, /* preconfiguration */
NULL, /* postconfiguration */
NULL, /* create main configuration */
NULL, /* init main configuration */
ngx_http_upstream_random_create_conf, /* create server configuration */
NULL, /* merge server configuration */
NULL, /* create location configuration */
NULL /* merge location configuration */
};
ngx_module_t ngx_http_upstream_random_module = {
NGX_MODULE_V1,
&ngx_http_upstream_random_module_ctx, /* module context */
ngx_http_upstream_random_commands, /* module directives */
NGX_HTTP_MODULE, /* module type */
NULL, /* init master */
NULL, /* init module */
NULL, /* init process */
NULL, /* init thread */
NULL, /* exit thread */
NULL, /* exit process */
NULL, /* exit master */
NGX_MODULE_V1_PADDING
};
static ngx_int_t
ngx_http_upstream_init_random(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us)
{
ngx_log_debug0(NGX_LOG_DEBUG_HTTP, cf->log, 0, "init random");
if (ngx_http_upstream_init_round_robin(cf, us) != NGX_OK) {
return NGX_ERROR;
}
us->peer.init = ngx_http_upstream_init_random_peer;
#if (NGX_HTTP_UPSTREAM_ZONE)
if (us->shm_zone) {
return NGX_OK;
}
#endif
return ngx_http_upstream_update_random(cf->pool, us);
}
static ngx_int_t
ngx_http_upstream_update_random(ngx_pool_t *pool,
ngx_http_upstream_srv_conf_t *us)
{
size_t size;
ngx_uint_t i, total_weight;
ngx_http_upstream_rr_peer_t *peer;
ngx_http_upstream_rr_peers_t *peers;
ngx_http_upstream_random_range_t *ranges;
ngx_http_upstream_random_srv_conf_t *rcf;
rcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_random_module);
peers = us->peer.data;
size = peers->number * sizeof(ngx_http_upstream_random_range_t);
ranges = pool ? ngx_palloc(pool, size) : ngx_alloc(size, ngx_cycle->log);
if (ranges == NULL) {
return NGX_ERROR;
}
total_weight = 0;
for (peer = peers->peer, i = 0; peer; peer = peer->next, i++) {
ranges[i].peer = peer;
ranges[i].range = total_weight;
total_weight += peer->weight;
}
rcf->ranges = ranges;
return NGX_OK;
}
static ngx_int_t
ngx_http_upstream_init_random_peer(ngx_http_request_t *r,
ngx_http_upstream_srv_conf_t *us)
{
ngx_http_upstream_random_srv_conf_t *rcf;
ngx_http_upstream_random_peer_data_t *rp;
ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"init random peer");
rcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_random_module);
rp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_random_peer_data_t));
if (rp == NULL) {
return NGX_ERROR;
}
r->upstream->peer.data = &rp->rrp;
if (ngx_http_upstream_init_round_robin_peer(r, us) != NGX_OK) {
return NGX_ERROR;
}
if (rcf->two) {
r->upstream->peer.get = ngx_http_upstream_get_random2_peer;
} else {
r->upstream->peer.get = ngx_http_upstream_get_random_peer;
}
rp->conf = rcf;
rp->tries = 0;
ngx_http_upstream_rr_peers_rlock(rp->rrp.peers);
#if (NGX_HTTP_UPSTREAM_ZONE)
if (rp->rrp.peers->shpool && rcf->ranges == NULL) {
if (ngx_http_upstream_update_random(NULL, us) != NGX_OK) {
ngx_http_upstream_rr_peers_unlock(rp->rrp.peers);
return NGX_ERROR;
}
}
#endif
ngx_http_upstream_rr_peers_unlock(rp->rrp.peers);
return NGX_OK;
}
static ngx_int_t
ngx_http_upstream_get_random_peer(ngx_peer_connection_t *pc, void *data)
{
ngx_http_upstream_random_peer_data_t *rp = data;
time_t now;
uintptr_t m;
ngx_uint_t i, n;
ngx_http_upstream_rr_peer_t *peer;
ngx_http_upstream_rr_peers_t *peers;
ngx_http_upstream_rr_peer_data_t *rrp;
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
"get random peer, try: %ui", pc->tries);
rrp = &rp->rrp;
peers = rrp->peers;
ngx_http_upstream_rr_peers_rlock(peers);
if (rp->tries > 20 || peers->single) {
ngx_http_upstream_rr_peers_unlock(peers);
return ngx_http_upstream_get_round_robin_peer(pc, rrp);
}
pc->cached = 0;
pc->connection = NULL;
now = ngx_time();
for ( ;; ) {
i = ngx_http_upstream_peek_random_peer(peers, rp);
peer = rp->conf->ranges[i].peer;
n = i / (8 * sizeof(uintptr_t));
m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t));
if (rrp->tried[n] & m) {
goto next;
}
ngx_http_upstream_rr_peer_lock(peers, peer);
if (peer->down) {
ngx_http_upstream_rr_peer_unlock(peers, peer);
goto next;
}
if (peer->max_fails
&& peer->fails >= peer->max_fails
&& now - peer->checked <= peer->fail_timeout)
{
ngx_http_upstream_rr_peer_unlock(peers, peer);
goto next;
}
if (peer->max_conns && peer->conns >= peer->max_conns) {
ngx_http_upstream_rr_peer_unlock(peers, peer);
goto next;
}
break;
next:
if (++rp->tries > 20) {
ngx_http_upstream_rr_peers_unlock(peers);
return ngx_http_upstream_get_round_robin_peer(pc, rrp);
}
}
rrp->current = peer;
if (now - peer->checked > peer->fail_timeout) {
peer->checked = now;
}
pc->sockaddr = peer->sockaddr;
pc->socklen = peer->socklen;
pc->name = &peer->name;
peer->conns++;
ngx_http_upstream_rr_peer_unlock(peers, peer);
ngx_http_upstream_rr_peers_unlock(peers);
rrp->tried[n] |= m;
return NGX_OK;
}
static ngx_int_t
ngx_http_upstream_get_random2_peer(ngx_peer_connection_t *pc, void *data)
{
ngx_http_upstream_random_peer_data_t *rp = data;
time_t now;
uintptr_t m;
ngx_uint_t i, n, p;
ngx_http_upstream_rr_peer_t *peer, *prev;
ngx_http_upstream_rr_peers_t *peers;
ngx_http_upstream_rr_peer_data_t *rrp;
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
"get random2 peer, try: %ui", pc->tries);
rrp = &rp->rrp;
peers = rrp->peers;
ngx_http_upstream_rr_peers_wlock(peers);
if (rp->tries > 20 || peers->single) {
ngx_http_upstream_rr_peers_unlock(peers);
return ngx_http_upstream_get_round_robin_peer(pc, rrp);
}
pc->cached = 0;
pc->connection = NULL;
now = ngx_time();
prev = NULL;
#if (NGX_SUPPRESS_WARN)
p = 0;
#endif
for ( ;; ) {
i = ngx_http_upstream_peek_random_peer(peers, rp);
peer = rp->conf->ranges[i].peer;
if (peer == prev) {
goto next;
}
n = i / (8 * sizeof(uintptr_t));
m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t));
if (rrp->tried[n] & m) {
goto next;
}
if (peer->down) {
goto next;
}
if (peer->max_fails
&& peer->fails >= peer->max_fails
&& now - peer->checked <= peer->fail_timeout)
{
goto next;
}
if (peer->max_conns && peer->conns >= peer->max_conns) {
goto next;
}
if (prev) {
if (peer->conns * prev->weight > prev->conns * peer->weight) {
peer = prev;
n = p / (8 * sizeof(uintptr_t));
m = (uintptr_t) 1 << p % (8 * sizeof(uintptr_t));
}
break;
}
prev = peer;
p = i;
next:
if (++rp->tries > 20) {
ngx_http_upstream_rr_peers_unlock(peers);
return ngx_http_upstream_get_round_robin_peer(pc, rrp);
}
}
rrp->current = peer;
if (now - peer->checked > peer->fail_timeout) {
peer->checked = now;
}
pc->sockaddr = peer->sockaddr;
pc->socklen = peer->socklen;
pc->name = &peer->name;
peer->conns++;
ngx_http_upstream_rr_peers_unlock(peers);
rrp->tried[n] |= m;
return NGX_OK;
}
static ngx_uint_t
ngx_http_upstream_peek_random_peer(ngx_http_upstream_rr_peers_t *peers,
ngx_http_upstream_random_peer_data_t *rp)
{
ngx_uint_t i, j, k, x;
x = ngx_random() % peers->total_weight;
i = 0;
j = peers->number;
while (j - i > 1) {
k = (i + j) / 2;
if (x < rp->conf->ranges[k].range) {
j = k;
} else {
i = k;
}
}
return i;
}
static void *
ngx_http_upstream_random_create_conf(ngx_conf_t *cf)
{
ngx_http_upstream_random_srv_conf_t *conf;
conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_random_srv_conf_t));
if (conf == NULL) {
return NULL;
}
/*
* set by ngx_pcalloc():
*
* conf->two = 0;
*/
return conf;
}
static char *
ngx_http_upstream_random(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
ngx_http_upstream_random_srv_conf_t *rcf = conf;
ngx_str_t *value;
ngx_http_upstream_srv_conf_t *uscf;
uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_upstream_module);
if (uscf->peer.init_upstream) {
ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
"load balancing method redefined");
}
uscf->peer.init_upstream = ngx_http_upstream_init_random;
uscf->flags = NGX_HTTP_UPSTREAM_CREATE
|NGX_HTTP_UPSTREAM_WEIGHT
|NGX_HTTP_UPSTREAM_MAX_CONNS
|NGX_HTTP_UPSTREAM_MAX_FAILS
|NGX_HTTP_UPSTREAM_FAIL_TIMEOUT
|NGX_HTTP_UPSTREAM_DOWN;
if (cf->args->nelts == 1) {
return NGX_CONF_OK;
}
value = cf->args->elts;
if (ngx_strcmp(value[1].data, "two") == 0) {
rcf->two = 1;
} else {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"invalid parameter \"%V\"", &value[1]);
return NGX_CONF_ERROR;
}
if (cf->args->nelts == 2) {
return NGX_CONF_OK;
}
if (ngx_strcmp(value[2].data, "least_conn") != 0) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"invalid parameter \"%V\"", &value[2]);
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
}