diff options
Diffstat (limited to 'src/core/ext/filters/client_channel/resolver/dns')
5 files changed, 121 insertions, 26 deletions
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 aa93e5d8de..c3c62b60bf 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 <grpc/support/alloc.h> #include <grpc/support/string_util.h> +#include <address_sorting/address_sorting.h> + #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" @@ -133,6 +135,7 @@ AresDnsResolver::AresDnsResolver(const ResolverArgs& args) if (path[0] == '/') ++path; name_to_resolve_ = gpr_strdup(path); // Get DNS server from URI authority. + dns_server_ = nullptr; if (0 != strcmp(args.uri->authority, "")) { dns_server_ = gpr_strdup(args.uri->authority); } @@ -360,6 +363,15 @@ void AresDnsResolver::OnResolvedLocked(void* arg, grpc_error* error) { } void AresDnsResolver::MaybeStartResolvingLocked() { + // If there is an existing timer, the time it fires is the earliest time we + // can start the next resolution. + if (have_next_resolution_timer_) { + // TODO(dgq): remove the following two lines once Pick First stops + // discarding subchannels after selecting. + ++resolved_version_; + MaybeFinishNextLocked(); + return; + } if (last_resolution_timestamp_ >= 0) { const grpc_millis earliest_next_resolution = last_resolution_timestamp_ + min_time_between_resolutions_; @@ -372,17 +384,15 @@ void AresDnsResolver::MaybeStartResolvingLocked() { "In cooldown from last resolution (from %" PRIdPTR " ms ago). Will resolve again in %" PRIdPTR " ms", last_resolution_ago, ms_until_next_resolution); - if (!have_next_resolution_timer_) { - have_next_resolution_timer_ = true; - // TODO(roth): We currently deal with this ref manually. Once the - // new closure API is done, find a way to track this ref with the timer - // callback as part of the type system. - RefCountedPtr<Resolver> self = - Ref(DEBUG_LOCATION, "next_resolution_timer_cooldown"); - self.release(); - grpc_timer_init(&next_resolution_timer_, ms_until_next_resolution, - &on_next_resolution_); - } + have_next_resolution_timer_ = true; + // TODO(roth): We currently deal with this ref manually. Once the + // new closure API is done, find a way to track this ref with the timer + // callback as part of the type system. + RefCountedPtr<Resolver> self = + Ref(DEBUG_LOCATION, "next_resolution_timer_cooldown"); + self.release(); + grpc_timer_init(&next_resolution_timer_, ms_until_next_resolution, + &on_next_resolution_); // TODO(dgq): remove the following two lines once Pick First stops // discarding subchannels after selecting. ++resolved_version_; @@ -394,6 +404,7 @@ void AresDnsResolver::MaybeStartResolvingLocked() { } void AresDnsResolver::StartResolvingLocked() { + gpr_log(GPR_DEBUG, "Start resolving."); // TODO(roth): We currently deal with this ref manually. Once the // new closure API is done, find a way to track this ref with the timer // callback as part of the type system. @@ -440,17 +451,32 @@ class AresDnsResolverFactory : public ResolverFactory { } // namespace grpc_core +extern grpc_address_resolver_vtable* grpc_resolve_address_impl; +static grpc_address_resolver_vtable* default_resolver; + +static grpc_error* blocking_resolve_address_ares( + const char* name, const char* default_port, + grpc_resolved_addresses** addresses) { + return default_resolver->blocking_resolve_address(name, default_port, + addresses); +} + +static grpc_address_resolver_vtable ares_resolver = { + grpc_resolve_address_ares, blocking_resolve_address_ares}; + void grpc_resolver_dns_ares_init() { char* resolver_env = gpr_getenv("GRPC_DNS_RESOLVER"); /* 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); return; } - grpc_resolve_address = grpc_resolve_address_ares; + default_resolver = grpc_resolve_address_impl; + grpc_set_resolver_impl(&ares_resolver); grpc_core::ResolverRegistry::Builder::RegisterResolverFactory( grpc_core::UniquePtr<grpc_core::ResolverFactory>( grpc_core::New<grpc_core::AresDnsResolverFactory>())); @@ -461,6 +487,7 @@ 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_ev_driver.h b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h index 0bc13e35f4..6239549534 100644 --- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h +++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h @@ -22,7 +22,6 @@ #include <grpc/support/port_platform.h> #include <ares.h> -#include "src/core/lib/iomgr/exec_ctx.h" #include "src/core/lib/iomgr/pollset_set.h" typedef struct grpc_ares_ev_driver grpc_ares_ev_driver; 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..e86ab5a37e 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 <grpc/support/string_util.h> #include <grpc/support/time.h> +#include <address_sorting/address_sorting.h> #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 +100,63 @@ 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 "]=<unprintable>", + 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"); + } +} + +/* Allow tests to access grpc_ares_wrapper_address_sorting_sort */ +void grpc_cares_wrapper_test_only_address_sorting_sort( + grpc_lb_addresses* lb_addrs) { + grpc_cares_wrapper_address_sorting_sort(lb_addrs); +} + 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_lb_addresses* lb_addrs = *(r->lb_addrs_out); + if (lb_addrs != nullptr) { + grpc_cares_wrapper_address_sorting_sort(lb_addrs); + } 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 bda9cd1729..2d84a038d6 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 @@ -22,11 +22,12 @@ #include <grpc/support/port_platform.h> #include "src/core/ext/filters/client_channel/lb_policy_factory.h" -#include "src/core/lib/iomgr/exec_ctx.h" #include "src/core/lib/iomgr/iomgr.h" #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 @@ -65,5 +66,9 @@ 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_test_only_address_sorting_sort( + grpc_lb_addresses* lb_addrs); + #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_WRAPPER_H \ */ diff --git a/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc b/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc index fbab136421..e7842a7951 100644 --- a/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc +++ b/src/core/ext/filters/client_channel/resolver/dns/native/dns_resolver.cc @@ -236,6 +236,15 @@ void NativeDnsResolver::OnResolvedLocked(void* arg, grpc_error* error) { } void NativeDnsResolver::MaybeStartResolvingLocked() { + // If there is an existing timer, the time it fires is the earliest time we + // can start the next resolution. + if (have_next_resolution_timer_) { + // TODO(dgq): remove the following two lines once Pick First stops + // discarding subchannels after selecting. + ++resolved_version_; + MaybeFinishNextLocked(); + return; + } if (last_resolution_timestamp_ >= 0) { const grpc_millis earliest_next_resolution = last_resolution_timestamp_ + min_time_between_resolutions_; @@ -248,17 +257,15 @@ void NativeDnsResolver::MaybeStartResolvingLocked() { "In cooldown from last resolution (from %" PRIdPTR " ms ago). Will resolve again in %" PRIdPTR " ms", last_resolution_ago, ms_until_next_resolution); - if (!have_next_resolution_timer_) { - have_next_resolution_timer_ = true; - // TODO(roth): We currently deal with this ref manually. Once the - // new closure API is done, find a way to track this ref with the timer - // callback as part of the type system. - RefCountedPtr<Resolver> self = - Ref(DEBUG_LOCATION, "next_resolution_timer_cooldown"); - self.release(); - grpc_timer_init(&next_resolution_timer_, ms_until_next_resolution, - &on_next_resolution_); - } + have_next_resolution_timer_ = true; + // TODO(roth): We currently deal with this ref manually. Once the + // new closure API is done, find a way to track this ref with the timer + // callback as part of the type system. + RefCountedPtr<Resolver> self = + Ref(DEBUG_LOCATION, "next_resolution_timer_cooldown"); + self.release(); + grpc_timer_init(&next_resolution_timer_, ms_until_next_resolution, + &on_next_resolution_); // TODO(dgq): remove the following two lines once Pick First stops // discarding subchannels after selecting. ++resolved_version_; @@ -270,6 +277,7 @@ void NativeDnsResolver::MaybeStartResolvingLocked() { } void NativeDnsResolver::StartResolvingLocked() { + gpr_log(GPR_DEBUG, "Start resolving."); // TODO(roth): We currently deal with this ref manually. Once the // new closure API is done, find a way to track this ref with the timer // callback as part of the type system. |