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Diffstat (limited to 'src/core/ext/lb_policy/grpclb/grpclb.c')
-rw-r--r--src/core/ext/lb_policy/grpclb/grpclb.c120
1 files changed, 84 insertions, 36 deletions
diff --git a/src/core/ext/lb_policy/grpclb/grpclb.c b/src/core/ext/lb_policy/grpclb/grpclb.c
index 412090158a..6da4febf26 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb.c
+++ b/src/core/ext/lb_policy/grpclb/grpclb.c
@@ -96,6 +96,12 @@
* - Implement LB service forwarding (point 2c. in the doc's diagram).
*/
+/* With the addition of a libuv endpoint, sockaddr.h now includes uv.h when
+ using that endpoint. Because of various transitive includes in uv.h,
+ including windows.h on Windows, uv.h must be included before other system
+ headers. Therefore, sockaddr.h must always be included first */
+#include "src/core/lib/iomgr/sockaddr.h"
+
#include <errno.h>
#include <string.h>
@@ -114,7 +120,6 @@
#include "src/core/ext/lb_policy/grpclb/grpclb.h"
#include "src/core/ext/lb_policy/grpclb/load_balancer_api.h"
#include "src/core/lib/channel/channel_args.h"
-#include "src/core/lib/iomgr/sockaddr.h"
#include "src/core/lib/iomgr/sockaddr_utils.h"
#include "src/core/lib/support/string.h"
#include "src/core/lib/surface/call.h"
@@ -338,6 +343,21 @@ static bool is_server_valid(const grpc_grpclb_server *server, size_t idx,
return true;
}
+/* vtable for LB tokens in grpc_lb_addresses. */
+static void *lb_token_copy(void *token) {
+ return token == NULL ? NULL : GRPC_MDELEM_REF(token);
+}
+static void lb_token_destroy(void *token) {
+ if (token != NULL) GRPC_MDELEM_UNREF(token);
+}
+static int lb_token_cmp(void *token1, void *token2) {
+ if (token1 > token2) return 1;
+ if (token1 < token2) return -1;
+ return 0;
+}
+static const grpc_lb_user_data_vtable lb_token_vtable = {
+ lb_token_copy, lb_token_destroy, lb_token_cmp};
+
/* Returns addresses extracted from \a serverlist. */
static grpc_lb_addresses *process_serverlist(
const grpc_grpclb_serverlist *serverlist) {
@@ -349,7 +369,8 @@ static grpc_lb_addresses *process_serverlist(
}
if (num_valid == 0) return NULL;
- grpc_lb_addresses *lb_addresses = grpc_lb_addresses_create(num_valid);
+ grpc_lb_addresses *lb_addresses =
+ grpc_lb_addresses_create(num_valid, &lb_token_vtable);
/* second pass: actually populate the addresses and LB tokens (aka user data
* to the outside world) to be read by the RR policy during its creation.
@@ -396,7 +417,7 @@ static grpc_lb_addresses *process_serverlist(
gpr_log(GPR_ERROR,
"Missing LB token for backend address '%s'. The empty token will "
"be used instead",
- grpc_sockaddr_to_uri((struct sockaddr *)&addr.addr));
+ grpc_sockaddr_to_uri(&addr));
user_data = GRPC_MDELEM_LB_TOKEN_EMPTY;
}
@@ -410,11 +431,6 @@ static grpc_lb_addresses *process_serverlist(
return lb_addresses;
}
-/* A plugin for grpc_lb_addresses_destroy that unrefs the LB token metadata. */
-static void lb_token_destroy(void *token) {
- if (token != NULL) GRPC_MDELEM_UNREF(token);
-}
-
/* perform a pick over \a rr_policy. Given that a pick can return immediately
* (ignoring its completion callback) we need to perform the cleanups this
* callback would be otherwise resposible for */
@@ -454,20 +470,27 @@ static grpc_lb_policy *create_rr_locked(
glb_lb_policy *glb_policy) {
GPR_ASSERT(serverlist != NULL && serverlist->num_servers > 0);
+ if (glb_policy->addresses != NULL) {
+ /* dispose of the previous version */
+ grpc_lb_addresses_destroy(glb_policy->addresses);
+ }
+ glb_policy->addresses = process_serverlist(serverlist);
+
grpc_lb_policy_args args;
memset(&args, 0, sizeof(args));
- args.server_name = glb_policy->server_name;
args.client_channel_factory = glb_policy->cc_factory;
- args.addresses = process_serverlist(serverlist);
- args.additional_args = glb_policy->args;
- grpc_lb_policy *rr = grpc_lb_policy_create(exec_ctx, "round_robin", &args);
+ // Replace the LB addresses in the channel args that we pass down to
+ // the subchannel.
+ static const char *keys_to_remove[] = {GRPC_ARG_LB_ADDRESSES};
+ const grpc_arg arg =
+ grpc_lb_addresses_create_channel_arg(glb_policy->addresses);
+ args.args = grpc_channel_args_copy_and_add_and_remove(
+ glb_policy->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &arg,
+ 1);
- if (glb_policy->addresses != NULL) {
- /* dispose of the previous version */
- grpc_lb_addresses_destroy(glb_policy->addresses, lb_token_destroy);
- }
- glb_policy->addresses = args.addresses;
+ grpc_lb_policy *rr = grpc_lb_policy_create(exec_ctx, "round_robin", &args);
+ grpc_channel_args_destroy(args.args);
return rr;
}
@@ -563,6 +586,12 @@ static void glb_rr_connectivity_changed(grpc_exec_ctx *exec_ctx, void *arg,
static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
grpc_lb_policy_factory *factory,
grpc_lb_policy_args *args) {
+ /* Get server name. */
+ const grpc_arg *arg =
+ grpc_channel_args_find(args->args, GRPC_ARG_SERVER_NAME);
+ const char *server_name =
+ arg != NULL && arg->type == GRPC_ARG_STRING ? arg->value.string : NULL;
+
/* Count the number of gRPC-LB addresses. There must be at least one.
* TODO(roth): For now, we ignore non-balancer addresses, but in the
* future, we may change the behavior such that we fall back to using
@@ -570,24 +599,27 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
* time, this should be changed to allow a list with no balancer addresses,
* since the resolver might fail to return a balancer address even when
* this is the right LB policy to use. */
+ arg = grpc_channel_args_find(args->args, GRPC_ARG_LB_ADDRESSES);
+ GPR_ASSERT(arg != NULL && arg->type == GRPC_ARG_POINTER);
+ grpc_lb_addresses *addresses = arg->value.pointer.p;
size_t num_grpclb_addrs = 0;
- for (size_t i = 0; i < args->addresses->num_addresses; ++i) {
- if (args->addresses->addresses[i].is_balancer) ++num_grpclb_addrs;
+ for (size_t i = 0; i < addresses->num_addresses; ++i) {
+ if (addresses->addresses[i].is_balancer) ++num_grpclb_addrs;
}
if (num_grpclb_addrs == 0) return NULL;
glb_lb_policy *glb_policy = gpr_malloc(sizeof(*glb_policy));
memset(glb_policy, 0, sizeof(*glb_policy));
- /* All input addresses in args->addresses come from a resolver that claims
+ /* All input addresses in addresses come from a resolver that claims
* they are LB services. It's the resolver's responsibility to make sure
* this
* policy is only instantiated and used in that case.
*
* Create a client channel over them to communicate with a LB service */
- glb_policy->server_name = gpr_strdup(args->server_name);
+ glb_policy->server_name = gpr_strdup(server_name);
glb_policy->cc_factory = args->client_channel_factory;
- glb_policy->args = grpc_channel_args_copy(args->additional_args);
+ glb_policy->args = grpc_channel_args_copy(args->args);
GPR_ASSERT(glb_policy->cc_factory != NULL);
/* construct a target from the addresses in args, given in the form
@@ -595,22 +627,19 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
* TODO(dgq): support mixed ip version */
char **addr_strs = gpr_malloc(sizeof(char *) * num_grpclb_addrs);
size_t addr_index = 0;
- for (size_t i = 0; i < args->addresses->num_addresses; i++) {
- if (args->addresses->addresses[i].user_data != NULL) {
+ for (size_t i = 0; i < addresses->num_addresses; i++) {
+ if (addresses->addresses[i].user_data != NULL) {
gpr_log(GPR_ERROR,
"This LB policy doesn't support user data. It will be ignored");
}
- if (args->addresses->addresses[i].is_balancer) {
+ if (addresses->addresses[i].is_balancer) {
if (addr_index == 0) {
- addr_strs[addr_index++] = grpc_sockaddr_to_uri(
- (const struct sockaddr *)&args->addresses->addresses[i]
- .address.addr);
+ addr_strs[addr_index++] =
+ grpc_sockaddr_to_uri(&addresses->addresses[i].address);
} else {
- GPR_ASSERT(grpc_sockaddr_to_string(
- &addr_strs[addr_index++],
- (const struct sockaddr *)&args->addresses->addresses[i]
- .address.addr,
- true) > 0);
+ GPR_ASSERT(grpc_sockaddr_to_string(&addr_strs[addr_index++],
+ &addresses->addresses[i].address,
+ true) > 0);
}
}
}
@@ -618,10 +647,29 @@ static grpc_lb_policy *glb_create(grpc_exec_ctx *exec_ctx,
char *target_uri_str = gpr_strjoin_sep((const char **)addr_strs,
num_grpclb_addrs, ",", &uri_path_len);
- /* will pick using pick_first */
+ /* Create a channel to talk to the LBs.
+ *
+ * We strip out the channel arg for the LB policy name, since we want
+ * to use the default (pick_first) in this case.
+ *
+ * We also strip out the channel arg for the resolved addresses, since
+ * that will be generated by the name resolver used in the LB channel.
+ * Note that the LB channel will use the sockaddr resolver, so this
+ * won't actually generate a query to DNS (or some other name service).
+ * However, the addresses returned by the sockaddr resolver will have
+ * is_balancer=false, whereas our own addresses have is_balancer=true.
+ * We need the LB channel to return addresses with is_balancer=false
+ * so that it does not wind up recursively using the grpclb LB policy,
+ * as per the special case logic in client_channel.c.
+ */
+ static const char *keys_to_remove[] = {GRPC_ARG_LB_POLICY_NAME,
+ GRPC_ARG_LB_ADDRESSES};
+ grpc_channel_args *new_args = grpc_channel_args_copy_and_remove(
+ args->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove));
glb_policy->lb_channel = grpc_client_channel_factory_create_channel(
exec_ctx, glb_policy->cc_factory, target_uri_str,
- GRPC_CLIENT_CHANNEL_TYPE_LOAD_BALANCING, NULL);
+ GRPC_CLIENT_CHANNEL_TYPE_LOAD_BALANCING, new_args);
+ grpc_channel_args_destroy(new_args);
gpr_free(target_uri_str);
for (size_t i = 0; i < num_grpclb_addrs; i++) {
@@ -662,7 +710,7 @@ static void glb_destroy(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
grpc_grpclb_destroy_serverlist(glb_policy->serverlist);
}
gpr_mu_destroy(&glb_policy->mu);
- grpc_lb_addresses_destroy(glb_policy->addresses, lb_token_destroy);
+ grpc_lb_addresses_destroy(glb_policy->addresses);
gpr_free(glb_policy);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 22:52:35 +0000