From 690dde672a877083e29ee5af0b8252697aa48fa0 Mon Sep 17 00:00:00 2001 From: Alexander Polcyn Date: Wed, 18 Oct 2017 00:20:33 -0700 Subject: Add address sorting submodule for use in c-ares wrapper --- .../resolver/dns/c_ares/dns_resolver_ares.cc | 4 ++ .../resolver/dns/c_ares/grpc_ares_wrapper.cc | 49 +++++++++++++++++++++- .../resolver/dns/c_ares/grpc_ares_wrapper.h | 5 +++ 3 files changed, 57 insertions(+), 1 deletion(-) (limited to 'src/core') diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc index c63de3c509..5d297df1af 100644 --- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc +++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc @@ -28,6 +28,8 @@ #include #include +#include + #include "src/core/ext/filters/client_channel/http_connect_handshaker.h" #include "src/core/ext/filters/client_channel/lb_policy_registry.h" #include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h" @@ -458,6 +460,7 @@ void grpc_resolver_dns_ares_init() { /* TODO(zyc): Turn on c-ares based resolver by default after the address sorter and the CNAME support are added. */ if (resolver_env != nullptr && gpr_stricmp(resolver_env, "ares") == 0) { + address_sorting_init(); grpc_error* error = grpc_ares_init(); if (error != GRPC_ERROR_NONE) { GRPC_LOG_IF_ERROR("ares_library_init() failed", error); @@ -475,6 +478,7 @@ void grpc_resolver_dns_ares_init() { void grpc_resolver_dns_ares_shutdown() { char* resolver_env = gpr_getenv("GRPC_DNS_RESOLVER"); if (resolver_env != nullptr && gpr_stricmp(resolver_env, "ares") == 0) { + address_sorting_shutdown(); grpc_ares_cleanup(); } gpr_free(resolver_env); diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc index 71b06eb87e..97a2357a42 100644 --- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc +++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc @@ -33,6 +33,7 @@ #include #include +#include #include "src/core/ext/filters/client_channel/parse_address.h" #include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h" #include "src/core/lib/gpr/host_port.h" @@ -46,6 +47,9 @@ static gpr_once g_basic_init = GPR_ONCE_INIT; static gpr_mu g_init_mu; +grpc_core::TraceFlag grpc_trace_cares_address_sorting(false, + "cares_address_sorting"); + struct grpc_ares_request { /** indicates the DNS server to use, if specified */ struct ares_addr_port_node dns_server_addr; @@ -96,11 +100,54 @@ static void grpc_ares_request_ref(grpc_ares_request* r) { gpr_ref(&r->pending_queries); } +static void log_address_sorting_list(grpc_lb_addresses* lb_addrs, + const char* input_output_str) { + for (size_t i = 0; i < lb_addrs->num_addresses; i++) { + char* addr_str; + if (grpc_sockaddr_to_string(&addr_str, &lb_addrs->addresses[i].address, + true)) { + gpr_log(GPR_DEBUG, "c-ares address sorting: %s[%" PRIuPTR "]=%s", + input_output_str, i, addr_str); + gpr_free(addr_str); + } else { + gpr_log(GPR_DEBUG, + "c-ares address sorting: %s[%" PRIuPTR "]=", + input_output_str, i); + } + } +} + +void grpc_cares_wrapper_address_sorting_sort(grpc_lb_addresses* lb_addrs) { + if (grpc_trace_cares_address_sorting.enabled()) { + log_address_sorting_list(lb_addrs, "input"); + } + address_sorting_sortable* sortables = (address_sorting_sortable*)gpr_zalloc( + sizeof(address_sorting_sortable) * lb_addrs->num_addresses); + for (size_t i = 0; i < lb_addrs->num_addresses; i++) { + sortables[i].user_data = &lb_addrs->addresses[i]; + memcpy(&sortables[i].dest_addr.addr, &lb_addrs->addresses[i].address.addr, + lb_addrs->addresses[i].address.len); + sortables[i].dest_addr.len = lb_addrs->addresses[i].address.len; + } + address_sorting_rfc_6724_sort(sortables, lb_addrs->num_addresses); + grpc_lb_address* sorted_lb_addrs = (grpc_lb_address*)gpr_zalloc( + sizeof(grpc_lb_address) * lb_addrs->num_addresses); + for (size_t i = 0; i < lb_addrs->num_addresses; i++) { + sorted_lb_addrs[i] = *(grpc_lb_address*)sortables[i].user_data; + } + gpr_free(sortables); + gpr_free(lb_addrs->addresses); + lb_addrs->addresses = sorted_lb_addrs; + if (grpc_trace_cares_address_sorting.enabled()) { + log_address_sorting_list(lb_addrs, "output"); + } +} + static void grpc_ares_request_unref(grpc_ares_request* r) { /* If there are no pending queries, invoke on_done callback and destroy the request */ if (gpr_unref(&r->pending_queries)) { - /* TODO(zyc): Sort results with RFC6724 before invoking on_done. */ + grpc_cares_wrapper_address_sorting_sort(*(r->lb_addrs_out)); GRPC_CLOSURE_SCHED(r->on_done, r->error); gpr_mu_destroy(&r->mu); grpc_ares_ev_driver_destroy(r->ev_driver); diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h index 3e8ea01e12..afb0e41c38 100644 --- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h +++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h @@ -26,6 +26,8 @@ #include "src/core/lib/iomgr/polling_entity.h" #include "src/core/lib/iomgr/resolve_address.h" +extern grpc_core::TraceFlag grpc_trace_cares_address_sorting; + typedef struct grpc_ares_request grpc_ares_request; /* Asynchronously resolve \a name. Use \a default_port if a port isn't @@ -64,5 +66,8 @@ grpc_error* grpc_ares_init(void); it has been called the same number of times as grpc_ares_init(). */ void grpc_ares_cleanup(void); +/* Exposed only for testing */ +void grpc_cares_wrapper_address_sorting_sort(grpc_lb_addresses* lb_addrs); + #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H \ */ -- cgit v1.2.3