- fast-reload, fix to use atomic store for config variables with nopause.

diff --git a/config.h.in b/config.h.in
index bc39544c40568b59aabcf1e2458387460ca66afa..f04baa7e9e24508d2075455a647278aec312c06a 100644 (file)
--- a/config.h.in
+++ b/config.h.in
@@ -581,6 +581,9 @@
 /* Define to 1 if you have the <stdarg.h> header file. */
 #undef HAVE_STDARG_H
 
+/* Define to 1 if you have the <stdatomic.h> header file. */
+#undef HAVE_STDATOMIC_H
+
 /* Define to 1 if you have the <stdbool.h> header file. */
 #undef HAVE_STDBOOL_H
 

diff --git a/configure b/configure
index 062b5ba0206609623d3523e5d171edcd8037776f..e8b6910d26e11aa4db859372d59cc0f2cd373e40 100755 (executable)
--- a/configure
+++ b/configure
@@ -16007,6 +16007,14 @@ then :
 
 fi
 
+ac_fn_c_check_header_compile "$LINENO" "stdatomic.h" "ac_cv_header_stdatomic_h" "$ac_includes_default
+"
+if test "x$ac_cv_header_stdatomic_h" = xyes
+then :
+  printf "%s\n" "#define HAVE_STDATOMIC_H 1" >>confdefs.h
+
+fi
+
 
 # check for types.
 # Using own tests for int64* because autoconf builtin only give 32bit.

diff --git a/configure.ac b/configure.ac
index e85fd2eb6dd9d0f8f8dee29232e2982ca8f8b0ed..7b8ad44ccf16eb45d6cc698c0e934365f4a8cc4e 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -471,6 +471,7 @@ AC_CHECK_HEADERS([netioapi.h],,, [AC_INCLUDES_DEFAULT
 
 # Check for Linux timestamping headers
 AC_CHECK_HEADERS([linux/net_tstamp.h],,, [AC_INCLUDES_DEFAULT])
+AC_CHECK_HEADERS([stdatomic.h],,, [AC_INCLUDES_DEFAULT])
 
 # check for types.  
 # Using own tests for int64* because autoconf builtin only give 32bit.

diff --git a/daemon/remote.c b/daemon/remote.c
index 2b77d8763cc17bda78494bd65cabb2d54a751455..12214a005c288d37192788409d02a7d831c578a9 100644 (file)
--- a/daemon/remote.c
+++ b/daemon/remote.c
@@ -52,6 +52,9 @@
 #ifdef HAVE_OPENSSL_BN_H
 #include <openssl/bn.h>
 #endif
+#ifdef HAVE_STDATOMIC_H
+#include <stdatomic.h>
+#endif
 
 #include <ctype.h>
 #include "daemon/remote.h"
@@ -4153,6 +4156,351 @@ fr_finish_time(struct fast_reload_thread* fr, struct timeval* time_start,
        return 1;
 }
 
+#ifdef ATOMIC_POINTER_LOCK_FREE
+/** Fast reload thread, if atomics are available, copy the config items
+ * one by one with atomic store operations. */
+static void
+fr_atomic_copy_cfg(struct config_file* oldcfg, struct config_file* cfg,
+       struct config_file* newcfg)
+{
+#define COPY_VAR(var) oldcfg->var = cfg->var; atomic_store(&cfg->var, newcfg->var); newcfg->var = 0;
+       /* If config file items are missing from this list, they are
+        * not updated by fast-reload +p. */
+       /* For missing items, the oldcfg item is not updated, still NULL,
+        * and the cfg stays the same. The newcfg item is untouched.
+        * The newcfg item is then deleted later. */
+       /* Items that need synchronisation are omitted from the list.
+        * Use fast-reload without +p to update them together. */
+       COPY_VAR(verbosity);
+       COPY_VAR(stat_interval);
+       COPY_VAR(stat_cumulative);
+       COPY_VAR(stat_extended);
+       COPY_VAR(stat_inhibit_zero);
+       COPY_VAR(num_threads);
+       COPY_VAR(port);
+       COPY_VAR(do_ip4);
+       COPY_VAR(do_ip6);
+       COPY_VAR(do_nat64);
+       COPY_VAR(prefer_ip4);
+       COPY_VAR(prefer_ip6);
+       COPY_VAR(do_udp);
+       COPY_VAR(do_tcp);
+       COPY_VAR(max_reuse_tcp_queries);
+       COPY_VAR(tcp_reuse_timeout);
+       COPY_VAR(tcp_auth_query_timeout);
+       COPY_VAR(tcp_upstream);
+       COPY_VAR(udp_upstream_without_downstream);
+       COPY_VAR(tcp_mss);
+       COPY_VAR(outgoing_tcp_mss);
+       COPY_VAR(tcp_idle_timeout);
+       COPY_VAR(do_tcp_keepalive);
+       COPY_VAR(tcp_keepalive_timeout);
+       COPY_VAR(sock_queue_timeout);
+       COPY_VAR(proxy_protocol_port);
+       COPY_VAR(ssl_service_key);
+       COPY_VAR(ssl_service_pem);
+       COPY_VAR(ssl_port);
+       COPY_VAR(ssl_upstream);
+       COPY_VAR(tls_cert_bundle);
+       COPY_VAR(tls_win_cert);
+       COPY_VAR(tls_additional_port);
+       /* The first is used to walk throught the list but last is
+        * only used during config read. */
+       COPY_VAR(tls_session_ticket_keys.first);
+       COPY_VAR(tls_session_ticket_keys.last);
+       COPY_VAR(tls_ciphers);
+       COPY_VAR(tls_ciphersuites);
+       COPY_VAR(tls_use_sni);
+       COPY_VAR(https_port);
+       COPY_VAR(http_endpoint);
+       COPY_VAR(http_max_streams);
+       COPY_VAR(http_query_buffer_size);
+       COPY_VAR(http_response_buffer_size);
+       COPY_VAR(http_nodelay);
+       COPY_VAR(http_notls_downstream);
+       COPY_VAR(outgoing_num_ports);
+       COPY_VAR(outgoing_num_tcp);
+       COPY_VAR(incoming_num_tcp);
+       COPY_VAR(outgoing_avail_ports);
+       COPY_VAR(edns_buffer_size);
+       COPY_VAR(stream_wait_size);
+       COPY_VAR(msg_buffer_size);
+       COPY_VAR(msg_cache_size);
+       COPY_VAR(msg_cache_slabs);
+       COPY_VAR(num_queries_per_thread);
+       COPY_VAR(jostle_time);
+       COPY_VAR(rrset_cache_size);
+       COPY_VAR(rrset_cache_slabs);
+       COPY_VAR(host_ttl);
+       COPY_VAR(infra_cache_slabs);
+       COPY_VAR(infra_cache_numhosts);
+       COPY_VAR(infra_cache_min_rtt);
+       COPY_VAR(infra_cache_max_rtt);
+       COPY_VAR(infra_keep_probing);
+       COPY_VAR(delay_close);
+       COPY_VAR(udp_connect);
+       COPY_VAR(target_fetch_policy);
+       COPY_VAR(fast_server_permil);
+       COPY_VAR(fast_server_num);
+       COPY_VAR(if_automatic);
+       COPY_VAR(if_automatic_ports);
+       COPY_VAR(so_rcvbuf);
+       COPY_VAR(so_sndbuf);
+       COPY_VAR(so_reuseport);
+       COPY_VAR(ip_transparent);
+       COPY_VAR(ip_freebind);
+       COPY_VAR(ip_dscp);
+       /* Not copied because the length and items could then not match.
+          num_ifs, ifs, num_out_ifs, out_ifs
+       */
+       COPY_VAR(root_hints);
+       COPY_VAR(stubs);
+       COPY_VAR(forwards);
+       COPY_VAR(auths);
+       COPY_VAR(views);
+       COPY_VAR(donotqueryaddrs);
+#ifdef CLIENT_SUBNET
+       COPY_VAR(client_subnet);
+       COPY_VAR(client_subnet_zone);
+       COPY_VAR(client_subnet_opcode);
+       COPY_VAR(client_subnet_always_forward);
+       COPY_VAR(max_client_subnet_ipv4);
+       COPY_VAR(max_client_subnet_ipv6);
+       COPY_VAR(min_client_subnet_ipv4);
+       COPY_VAR(min_client_subnet_ipv6);
+       COPY_VAR(max_ecs_tree_size_ipv4);
+       COPY_VAR(max_ecs_tree_size_ipv6);
+#endif
+       COPY_VAR(acls);
+       COPY_VAR(donotquery_localhost);
+       COPY_VAR(tcp_connection_limits);
+       COPY_VAR(harden_short_bufsize);
+       COPY_VAR(harden_large_queries);
+       COPY_VAR(harden_glue);
+       COPY_VAR(harden_dnssec_stripped);
+       COPY_VAR(harden_below_nxdomain);
+       COPY_VAR(harden_referral_path);
+       COPY_VAR(harden_algo_downgrade);
+       COPY_VAR(harden_unknown_additional);
+       COPY_VAR(use_caps_bits_for_id);
+       COPY_VAR(caps_whitelist);
+       COPY_VAR(private_address);
+       COPY_VAR(private_domain);
+       COPY_VAR(unwanted_threshold);
+       COPY_VAR(max_ttl);
+       COPY_VAR(min_ttl);
+       COPY_VAR(max_negative_ttl);
+       COPY_VAR(prefetch);
+       COPY_VAR(prefetch_key);
+       COPY_VAR(deny_any);
+       COPY_VAR(chrootdir);
+       COPY_VAR(username);
+       COPY_VAR(directory);
+       COPY_VAR(logfile);
+       COPY_VAR(pidfile);
+       COPY_VAR(use_syslog);
+       COPY_VAR(log_time_ascii);
+       COPY_VAR(log_queries);
+       COPY_VAR(log_replies);
+       COPY_VAR(log_tag_queryreply);
+       COPY_VAR(log_local_actions);
+       COPY_VAR(log_servfail);
+       COPY_VAR(log_identity);
+       COPY_VAR(log_destaddr);
+       COPY_VAR(hide_identity);
+       COPY_VAR(hide_version);
+       COPY_VAR(hide_trustanchor);
+       COPY_VAR(hide_http_user_agent);
+       COPY_VAR(identity);
+       COPY_VAR(version);
+       COPY_VAR(http_user_agent);
+       COPY_VAR(nsid_cfg_str);
+       /* Not copied because the length and items could then not match.
+       nsid;
+       nsid_len;
+       */
+       COPY_VAR(module_conf);
+       COPY_VAR(trust_anchor_file_list);
+       COPY_VAR(trust_anchor_list);
+       COPY_VAR(auto_trust_anchor_file_list);
+       COPY_VAR(trusted_keys_file_list);
+       COPY_VAR(domain_insecure);
+       COPY_VAR(trust_anchor_signaling);
+       COPY_VAR(root_key_sentinel);
+       COPY_VAR(val_date_override);
+       COPY_VAR(val_sig_skew_min);
+       COPY_VAR(val_sig_skew_max);
+       COPY_VAR(val_max_restart);
+       COPY_VAR(bogus_ttl);
+       COPY_VAR(val_clean_additional);
+       COPY_VAR(val_log_level);
+       COPY_VAR(val_log_squelch);
+       COPY_VAR(val_permissive_mode);
+       COPY_VAR(aggressive_nsec);
+       COPY_VAR(ignore_cd);
+       COPY_VAR(disable_edns_do);
+       COPY_VAR(serve_expired);
+       COPY_VAR(serve_expired_ttl);
+       COPY_VAR(serve_expired_ttl_reset);
+       COPY_VAR(serve_expired_reply_ttl);
+       COPY_VAR(serve_expired_client_timeout);
+       COPY_VAR(ede_serve_expired);
+       COPY_VAR(serve_original_ttl);
+       COPY_VAR(val_nsec3_key_iterations);
+       COPY_VAR(zonemd_permissive_mode);
+       COPY_VAR(add_holddown);
+       COPY_VAR(del_holddown);
+       COPY_VAR(keep_missing);
+       COPY_VAR(permit_small_holddown);
+       COPY_VAR(key_cache_size);
+       COPY_VAR(key_cache_slabs);
+       COPY_VAR(neg_cache_size);
+       COPY_VAR(local_zones);
+       COPY_VAR(local_zones_nodefault);
+#ifdef USE_IPSET
+       COPY_VAR(local_zones_ipset);
+#endif
+       COPY_VAR(local_zones_disable_default);
+       COPY_VAR(local_data);
+       COPY_VAR(local_zone_overrides);
+       COPY_VAR(unblock_lan_zones);
+       COPY_VAR(insecure_lan_zones);
+       /* These reference tags
+       COPY_VAR(local_zone_tags);
+       COPY_VAR(acl_tags);
+       COPY_VAR(acl_tag_actions);
+       COPY_VAR(acl_tag_datas);
+       */
+       COPY_VAR(acl_view);
+       COPY_VAR(interface_actions);
+       /* These reference tags
+       COPY_VAR(interface_tags);
+       COPY_VAR(interface_tag_actions);
+       COPY_VAR(interface_tag_datas);
+       */
+       COPY_VAR(interface_view);
+       /* This references tags
+       COPY_VAR(respip_tags);
+       */
+       COPY_VAR(respip_actions);
+       COPY_VAR(respip_data);
+       /* Not copied because the length and items could then not match.
+        * also the respip module keeps a pointer to the array in its state.
+          tagname, num_tags
+       */
+       COPY_VAR(remote_control_enable);
+       /* The first is used to walk throught the list but last is
+        * only used during config read. */
+       COPY_VAR(control_ifs.first);
+       COPY_VAR(control_ifs.last);
+       COPY_VAR(control_use_cert);
+       COPY_VAR(control_port);
+       COPY_VAR(server_key_file);
+       COPY_VAR(server_cert_file);
+       COPY_VAR(control_key_file);
+       COPY_VAR(control_cert_file);
+       COPY_VAR(python_script);
+       COPY_VAR(dynlib_file);
+       COPY_VAR(use_systemd);
+       COPY_VAR(do_daemonize);
+       COPY_VAR(minimal_responses);
+       COPY_VAR(rrset_roundrobin);
+       COPY_VAR(unknown_server_time_limit);
+       COPY_VAR(max_udp_size);
+       COPY_VAR(dns64_prefix);
+       COPY_VAR(dns64_synthall);
+       COPY_VAR(dns64_ignore_aaaa);
+       COPY_VAR(nat64_prefix);
+       COPY_VAR(dnstap);
+       COPY_VAR(dnstap_bidirectional);
+       COPY_VAR(dnstap_socket_path);
+       COPY_VAR(dnstap_ip);
+       COPY_VAR(dnstap_tls);
+       COPY_VAR(dnstap_tls_server_name);
+       COPY_VAR(dnstap_tls_cert_bundle);
+       COPY_VAR(dnstap_tls_client_key_file);
+       COPY_VAR(dnstap_tls_client_cert_file);
+       COPY_VAR(dnstap_send_identity);
+       COPY_VAR(dnstap_send_version);
+       COPY_VAR(dnstap_identity);
+       COPY_VAR(dnstap_version);
+       COPY_VAR(dnstap_log_resolver_query_messages);
+       COPY_VAR(dnstap_log_resolver_response_messages);
+       COPY_VAR(dnstap_log_client_query_messages);
+       COPY_VAR(dnstap_log_client_response_messages);
+       COPY_VAR(dnstap_log_forwarder_query_messages);
+       COPY_VAR(dnstap_log_forwarder_response_messages);
+       COPY_VAR(disable_dnssec_lame_check);
+       COPY_VAR(ip_ratelimit);
+       COPY_VAR(ip_ratelimit_cookie);
+       COPY_VAR(ip_ratelimit_slabs);
+       COPY_VAR(ip_ratelimit_size);
+       COPY_VAR(ip_ratelimit_factor);
+       COPY_VAR(ip_ratelimit_backoff);
+       COPY_VAR(ratelimit);
+       COPY_VAR(ratelimit_slabs);
+       COPY_VAR(ratelimit_size);
+       COPY_VAR(ratelimit_for_domain);
+       COPY_VAR(ratelimit_below_domain);
+       COPY_VAR(ratelimit_factor);
+       COPY_VAR(ratelimit_backoff);
+       COPY_VAR(outbound_msg_retry);
+       COPY_VAR(max_sent_count);
+       COPY_VAR(max_query_restarts);
+       COPY_VAR(qname_minimisation);
+       COPY_VAR(qname_minimisation_strict);
+       COPY_VAR(shm_enable);
+       COPY_VAR(shm_key);
+       COPY_VAR(edns_client_strings);
+       COPY_VAR(edns_client_string_opcode);
+       COPY_VAR(dnscrypt);
+       COPY_VAR(dnscrypt_port);
+       COPY_VAR(dnscrypt_provider);
+       COPY_VAR(dnscrypt_secret_key);
+       COPY_VAR(dnscrypt_provider_cert);
+       COPY_VAR(dnscrypt_provider_cert_rotated);
+       COPY_VAR(dnscrypt_shared_secret_cache_size);
+       COPY_VAR(dnscrypt_shared_secret_cache_slabs);
+       COPY_VAR(dnscrypt_nonce_cache_size);
+       COPY_VAR(dnscrypt_nonce_cache_slabs);
+       COPY_VAR(pad_responses);
+       COPY_VAR(pad_responses_block_size);
+       COPY_VAR(pad_queries);
+       COPY_VAR(pad_queries_block_size);
+#ifdef USE_IPSECMOD
+       COPY_VAR(ipsecmod_enabled);
+       COPY_VAR(ipsecmod_whitelist);
+       COPY_VAR(ipsecmod_hook);
+       COPY_VAR(ipsecmod_ignore_bogus);
+       COPY_VAR(ipsecmod_max_ttl);
+       COPY_VAR(ipsecmod_strict);
+#endif
+#ifdef USE_CACHEDB
+       COPY_VAR(cachedb_backend);
+       COPY_VAR(cachedb_secret);
+       COPY_VAR(cachedb_no_store);
+#ifdef USE_REDIS
+       COPY_VAR(redis_server_host);
+       COPY_VAR(redis_server_port);
+       COPY_VAR(redis_server_path);
+       COPY_VAR(redis_server_password);
+       COPY_VAR(redis_timeout);
+       COPY_VAR(redis_expire_records);
+       COPY_VAR(redis_logical_db);
+#endif
+#endif
+       COPY_VAR(do_answer_cookie);
+       /* Not copied because the length and content could then not match.
+          cookie_secret[40], cookie_secret_len
+       */
+#ifdef USE_IPSET
+       COPY_VAR(ipset_name_v4);
+       COPY_VAR(ipset_name_v6);
+#endif
+       COPY_VAR(ede);
+}
+#endif /* ATOMIC_POINTER_LOCK_FREE */
+
 /** fast reload thread, reload config with putting the new config items
  * in place and swapping out the old items. */
 static int
@@ -4173,16 +4521,29 @@ fr_reload_config(struct fast_reload_thread* fr, struct config_file* newcfg,
        lock_rw_wrlock(&env->fwds->lock);
        lock_rw_wrlock(&env->hints->lock);
 
-       /* Store old config elements. */
-       *ct->oldcfg = *env->cfg;
-       /* Insert new config elements. */
-       *env->cfg = *newcfg;
+#ifdef ATOMIC_POINTER_LOCK_FREE
+       if(fr->fr_nopause) {
+               fr_atomic_copy_cfg(ct->oldcfg, env->cfg, newcfg);
+       } else {
+#endif
+               /* Store old config elements. */
+               *ct->oldcfg = *env->cfg;
+               /* Insert new config elements. */
+               *env->cfg = *newcfg;
+#ifdef ATOMIC_POINTER_LOCK_FREE
+       }
+#endif
+
        if(env->cfg->log_identity || ct->oldcfg->log_identity) {
                /* pick up new log_identity string to use for log output. */
                log_ident_set_or_default(env->cfg->log_identity);
        }
        /* the newcfg elements are in env->cfg, so should not be freed here. */
-       memset(newcfg, 0, sizeof(*newcfg));
+#ifdef ATOMIC_POINTER_LOCK_FREE
+       /* if used, the routine that copies the config has zeroed items. */
+       if(!fr->fr_nopause)
+#endif
+               memset(newcfg, 0, sizeof(*newcfg));
 
        /* Quickly swap the tree roots themselves with the already allocated
         * elements. This is a quick swap operation on the pointer.