| |
| /* |
| * Copyright (C) Igor Sysoev |
| * Copyright (C) Nginx, Inc. |
| */ |
| |
| |
| #include <ngx_config.h> |
| #include <ngx_core.h> |
| #include <ngx_http.h> |
| |
| |
| typedef struct { |
| /* the round robin data must be first */ |
| ngx_http_upstream_rr_peer_data_t rrp; |
| |
| ngx_uint_t hash; |
| |
| u_char addrlen; |
| u_char *addr; |
| |
| u_char tries; |
| |
| ngx_event_get_peer_pt get_rr_peer; |
| } ngx_http_upstream_ip_hash_peer_data_t; |
| |
| |
| static ngx_int_t ngx_http_upstream_init_ip_hash_peer(ngx_http_request_t *r, |
| ngx_http_upstream_srv_conf_t *us); |
| static ngx_int_t ngx_http_upstream_get_ip_hash_peer(ngx_peer_connection_t *pc, |
| void *data); |
| static char *ngx_http_upstream_ip_hash(ngx_conf_t *cf, ngx_command_t *cmd, |
| void *conf); |
| |
| |
| static ngx_command_t ngx_http_upstream_ip_hash_commands[] = { |
| |
| { ngx_string("ip_hash"), |
| NGX_HTTP_UPS_CONF|NGX_CONF_NOARGS, |
| ngx_http_upstream_ip_hash, |
| 0, |
| 0, |
| NULL }, |
| |
| ngx_null_command |
| }; |
| |
| |
| static ngx_http_module_t ngx_http_upstream_ip_hash_module_ctx = { |
| NULL, /* preconfiguration */ |
| NULL, /* postconfiguration */ |
| |
| NULL, /* create main configuration */ |
| NULL, /* init main configuration */ |
| |
| NULL, /* create server configuration */ |
| NULL, /* merge server configuration */ |
| |
| NULL, /* create location configuration */ |
| NULL /* merge location configuration */ |
| }; |
| |
| |
| ngx_module_t ngx_http_upstream_ip_hash_module = { |
| NGX_MODULE_V1, |
| &ngx_http_upstream_ip_hash_module_ctx, /* module context */ |
| ngx_http_upstream_ip_hash_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 u_char ngx_http_upstream_ip_hash_pseudo_addr[3]; |
| |
| |
| static ngx_int_t |
| ngx_http_upstream_init_ip_hash(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us) |
| { |
| if (ngx_http_upstream_init_round_robin(cf, us) != NGX_OK) { |
| return NGX_ERROR; |
| } |
| |
| us->peer.init = ngx_http_upstream_init_ip_hash_peer; |
| |
| return NGX_OK; |
| } |
| |
| |
| static ngx_int_t |
| ngx_http_upstream_init_ip_hash_peer(ngx_http_request_t *r, |
| ngx_http_upstream_srv_conf_t *us) |
| { |
| struct sockaddr_in *sin; |
| #if (NGX_HAVE_INET6) |
| struct sockaddr_in6 *sin6; |
| #endif |
| ngx_http_upstream_ip_hash_peer_data_t *iphp; |
| |
| iphp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_ip_hash_peer_data_t)); |
| if (iphp == NULL) { |
| return NGX_ERROR; |
| } |
| |
| r->upstream->peer.data = &iphp->rrp; |
| |
| if (ngx_http_upstream_init_round_robin_peer(r, us) != NGX_OK) { |
| return NGX_ERROR; |
| } |
| |
| r->upstream->peer.get = ngx_http_upstream_get_ip_hash_peer; |
| |
| switch (r->connection->sockaddr->sa_family) { |
| |
| case AF_INET: |
| sin = (struct sockaddr_in *) r->connection->sockaddr; |
| iphp->addr = (u_char *) &sin->sin_addr.s_addr; |
| iphp->addrlen = 3; |
| break; |
| |
| #if (NGX_HAVE_INET6) |
| case AF_INET6: |
| sin6 = (struct sockaddr_in6 *) r->connection->sockaddr; |
| iphp->addr = (u_char *) &sin6->sin6_addr.s6_addr; |
| iphp->addrlen = 16; |
| break; |
| #endif |
| |
| default: |
| iphp->addr = ngx_http_upstream_ip_hash_pseudo_addr; |
| iphp->addrlen = 3; |
| } |
| |
| iphp->hash = 89; |
| iphp->tries = 0; |
| iphp->get_rr_peer = ngx_http_upstream_get_round_robin_peer; |
| |
| return NGX_OK; |
| } |
| |
| |
| static ngx_int_t |
| ngx_http_upstream_get_ip_hash_peer(ngx_peer_connection_t *pc, void *data) |
| { |
| ngx_http_upstream_ip_hash_peer_data_t *iphp = data; |
| |
| time_t now; |
| ngx_int_t w; |
| uintptr_t m; |
| ngx_uint_t i, n, p, hash; |
| ngx_http_upstream_rr_peer_t *peer; |
| |
| ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, |
| "get ip hash peer, try: %ui", pc->tries); |
| |
| /* TODO: cached */ |
| |
| ngx_http_upstream_rr_peers_rlock(iphp->rrp.peers); |
| |
| if (iphp->tries > 20 || iphp->rrp.peers->single) { |
| ngx_http_upstream_rr_peers_unlock(iphp->rrp.peers); |
| return iphp->get_rr_peer(pc, &iphp->rrp); |
| } |
| |
| now = ngx_time(); |
| |
| pc->cached = 0; |
| pc->connection = NULL; |
| |
| hash = iphp->hash; |
| |
| for ( ;; ) { |
| |
| for (i = 0; i < (ngx_uint_t) iphp->addrlen; i++) { |
| hash = (hash * 113 + iphp->addr[i]) % 6271; |
| } |
| |
| w = hash % iphp->rrp.peers->total_weight; |
| peer = iphp->rrp.peers->peer; |
| p = 0; |
| |
| while (w >= peer->weight) { |
| w -= peer->weight; |
| peer = peer->next; |
| p++; |
| } |
| |
| n = p / (8 * sizeof(uintptr_t)); |
| m = (uintptr_t) 1 << p % (8 * sizeof(uintptr_t)); |
| |
| if (iphp->rrp.tried[n] & m) { |
| goto next; |
| } |
| |
| ngx_log_debug2(NGX_LOG_DEBUG_HTTP, pc->log, 0, |
| "get ip hash peer, hash: %ui %04XL", p, (uint64_t) m); |
| |
| ngx_http_upstream_rr_peer_lock(iphp->rrp.peers, peer); |
| |
| if (peer->down) { |
| ngx_http_upstream_rr_peer_unlock(iphp->rrp.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(iphp->rrp.peers, peer); |
| goto next; |
| } |
| |
| if (peer->max_conns && peer->conns >= peer->max_conns) { |
| ngx_http_upstream_rr_peer_unlock(iphp->rrp.peers, peer); |
| goto next; |
| } |
| |
| break; |
| |
| next: |
| |
| if (++iphp->tries > 20) { |
| ngx_http_upstream_rr_peers_unlock(iphp->rrp.peers); |
| return iphp->get_rr_peer(pc, &iphp->rrp); |
| } |
| } |
| |
| iphp->rrp.current = peer; |
| |
| pc->sockaddr = peer->sockaddr; |
| pc->socklen = peer->socklen; |
| pc->name = &peer->name; |
| |
| peer->conns++; |
| |
| if (now - peer->checked > peer->fail_timeout) { |
| peer->checked = now; |
| } |
| |
| ngx_http_upstream_rr_peer_unlock(iphp->rrp.peers, peer); |
| ngx_http_upstream_rr_peers_unlock(iphp->rrp.peers); |
| |
| iphp->rrp.tried[n] |= m; |
| iphp->hash = hash; |
| |
| return NGX_OK; |
| } |
| |
| |
| static char * |
| ngx_http_upstream_ip_hash(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) |
| { |
| 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_ip_hash; |
| |
| 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; |
| |
| return NGX_CONF_OK; |
| } |