static int cc_pick_subchannel(grpc_exec_ctx *exec_ctx, void *elemp,
grpc_metadata_batch *initial_metadata,
uint32_t initial_metadata_flags,
grpc_connected_subchannel **connected_subchannel,
grpc_closure *on_ready) {
grpc_call_element *elem = elemp;
channel_data *chand = elem->channel_data;
call_data *calld = elem->call_data;
continue_picking_args *cpa;
grpc_closure *closure;
GPR_ASSERT(connected_subchannel);
gpr_mu_lock(&chand->mu_config);
if (initial_metadata == NULL) {
if (chand->lb_policy != NULL) {
grpc_lb_policy_cancel_pick(exec_ctx, chand->lb_policy,
connected_subchannel);
}
for (closure = chand->waiting_for_config_closures.head; closure != NULL;
closure = grpc_closure_next(closure)) {
cpa = closure->cb_arg;
if (cpa->connected_subchannel == connected_subchannel) {
cpa->connected_subchannel = NULL;
grpc_exec_ctx_enqueue(exec_ctx, cpa->on_ready, false, NULL);
}
}
gpr_mu_unlock(&chand->mu_config);
return 1;
}
if (chand->lb_policy != NULL) {
grpc_lb_policy *lb_policy = chand->lb_policy;
int r;
GRPC_LB_POLICY_REF(lb_policy, "cc_pick_subchannel");
gpr_mu_unlock(&chand->mu_config);
r = grpc_lb_policy_pick(exec_ctx, lb_policy, calld->pollset,
initial_metadata, initial_metadata_flags,
connected_subchannel, on_ready);
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "cc_pick_subchannel");
return r;
}
if (chand->resolver != NULL && !chand->started_resolving) {
chand->started_resolving = 1;
GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
grpc_resolver_next(exec_ctx, chand->resolver,
&chand->incoming_configuration,
&chand->on_config_changed);
}
cpa = gpr_malloc(sizeof(*cpa));
cpa->initial_metadata = initial_metadata;
cpa->initial_metadata_flags = initial_metadata_flags;
cpa->connected_subchannel = connected_subchannel;
cpa->on_ready = on_ready;
cpa->elem = elem;
grpc_closure_init(&cpa->closure, continue_picking, cpa);
grpc_closure_list_add(&chand->waiting_for_config_closures, &cpa->closure, 1);
gpr_mu_unlock(&chand->mu_config);
return 0;
}
static bool pick_subchannel(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
grpc_metadata_batch *initial_metadata,
uint32_t initial_metadata_flags,
grpc_connected_subchannel **connected_subchannel,
grpc_closure *on_ready, grpc_error *error) {
GPR_TIMER_BEGIN("pick_subchannel", 0);
channel_data *chand = elem->channel_data;
call_data *calld = elem->call_data;
continue_picking_args *cpa;
grpc_closure *closure;
GPR_ASSERT(connected_subchannel);
gpr_mu_lock(&chand->mu);
if (initial_metadata == NULL) {
if (chand->lb_policy != NULL) {
grpc_lb_policy_cancel_pick(exec_ctx, chand->lb_policy,
connected_subchannel, GRPC_ERROR_REF(error));
}
for (closure = chand->waiting_for_config_closures.head; closure != NULL;
closure = closure->next_data.next) {
cpa = closure->cb_arg;
if (cpa->connected_subchannel == connected_subchannel) {
cpa->connected_subchannel = NULL;
grpc_exec_ctx_sched(
exec_ctx, cpa->on_ready,
GRPC_ERROR_CREATE_REFERENCING("Pick cancelled", &error, 1), NULL);
}
}
gpr_mu_unlock(&chand->mu);
GPR_TIMER_END("pick_subchannel", 0);
GRPC_ERROR_UNREF(error);
return true;
}
GPR_ASSERT(error == GRPC_ERROR_NONE);
if (chand->lb_policy != NULL) {
grpc_lb_policy *lb_policy = chand->lb_policy;
GRPC_LB_POLICY_REF(lb_policy, "pick_subchannel");
gpr_mu_unlock(&chand->mu);
// If the application explicitly set wait_for_ready, use that.
// Otherwise, if the service config specified a value for this
// method, use that.
const bool wait_for_ready_set_from_api =
initial_metadata_flags &
GRPC_INITIAL_METADATA_WAIT_FOR_READY_EXPLICITLY_SET;
const bool wait_for_ready_set_from_service_config =
calld->wait_for_ready_from_service_config != WAIT_FOR_READY_UNSET;
if (!wait_for_ready_set_from_api &&
wait_for_ready_set_from_service_config) {
if (calld->wait_for_ready_from_service_config == WAIT_FOR_READY_TRUE) {
initial_metadata_flags |= GRPC_INITIAL_METADATA_WAIT_FOR_READY;
} else {
initial_metadata_flags &= ~GRPC_INITIAL_METADATA_WAIT_FOR_READY;
}
}
// TODO(dgq): make this deadline configurable somehow.
const grpc_lb_policy_pick_args inputs = {
initial_metadata, initial_metadata_flags, &calld->lb_token_mdelem,
gpr_inf_future(GPR_CLOCK_MONOTONIC)};
const bool result = grpc_lb_policy_pick(
exec_ctx, lb_policy, &inputs, connected_subchannel, NULL, on_ready);
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "pick_subchannel");
GPR_TIMER_END("pick_subchannel", 0);
return result;
}
if (chand->resolver != NULL && !chand->started_resolving) {
chand->started_resolving = true;
GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
grpc_resolver_next(exec_ctx, chand->resolver, &chand->resolver_result,
&chand->on_resolver_result_changed);
}
if (chand->resolver != NULL) {
cpa = gpr_malloc(sizeof(*cpa));
cpa->initial_metadata = initial_metadata;
cpa->initial_metadata_flags = initial_metadata_flags;
cpa->connected_subchannel = connected_subchannel;
cpa->on_ready = on_ready;
cpa->elem = elem;
grpc_closure_init(&cpa->closure, continue_picking, cpa);
grpc_closure_list_append(&chand->waiting_for_config_closures, &cpa->closure,
GRPC_ERROR_NONE);
} else {
grpc_exec_ctx_sched(exec_ctx, on_ready, GRPC_ERROR_CREATE("Disconnected"),
NULL);
}
gpr_mu_unlock(&chand->mu);
GPR_TIMER_END("pick_subchannel", 0);
return false;
}
static bool pick_subchannel(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
grpc_metadata_batch *initial_metadata,
uint32_t initial_metadata_flags,
grpc_connected_subchannel **connected_subchannel,
grpc_closure *on_ready) {
GPR_TIMER_BEGIN("pick_subchannel", 0);
channel_data *chand = elem->channel_data;
call_data *calld = elem->call_data;
continue_picking_args *cpa;
grpc_closure *closure;
GPR_ASSERT(connected_subchannel);
gpr_mu_lock(&chand->mu);
if (initial_metadata == NULL) {
if (chand->lb_policy != NULL) {
grpc_lb_policy_cancel_pick(exec_ctx, chand->lb_policy,
connected_subchannel);
}
for (closure = chand->waiting_for_config_closures.head; closure != NULL;
closure = closure->next_data.next) {
cpa = closure->cb_arg;
if (cpa->connected_subchannel == connected_subchannel) {
cpa->connected_subchannel = NULL;
grpc_exec_ctx_sched(exec_ctx, cpa->on_ready,
GRPC_ERROR_CREATE("Pick cancelled"), NULL);
}
}
gpr_mu_unlock(&chand->mu);
GPR_TIMER_END("pick_subchannel", 0);
return true;
}
if (chand->lb_policy != NULL) {
grpc_lb_policy *lb_policy = chand->lb_policy;
int r;
GRPC_LB_POLICY_REF(lb_policy, "pick_subchannel");
gpr_mu_unlock(&chand->mu);
const grpc_lb_policy_pick_args inputs = {calld->pollent, initial_metadata,
initial_metadata_flags,
&calld->lb_token_mdelem};
r = grpc_lb_policy_pick(exec_ctx, lb_policy, &inputs, connected_subchannel,
NULL, on_ready);
GRPC_LB_POLICY_UNREF(exec_ctx, lb_policy, "pick_subchannel");
GPR_TIMER_END("pick_subchannel", 0);
return r;
}
if (chand->resolver != NULL && !chand->started_resolving) {
chand->started_resolving = true;
GRPC_CHANNEL_STACK_REF(chand->owning_stack, "resolver");
grpc_resolver_next(exec_ctx, chand->resolver, &chand->resolver_result,
&chand->on_resolver_result_changed);
}
if (chand->resolver != NULL) {
cpa = gpr_malloc(sizeof(*cpa));
cpa->initial_metadata = initial_metadata;
cpa->initial_metadata_flags = initial_metadata_flags;
cpa->connected_subchannel = connected_subchannel;
cpa->on_ready = on_ready;
cpa->elem = elem;
grpc_closure_init(&cpa->closure, continue_picking, cpa);
grpc_closure_list_append(&chand->waiting_for_config_closures, &cpa->closure,
GRPC_ERROR_NONE);
} else {
grpc_exec_ctx_sched(exec_ctx, on_ready, GRPC_ERROR_CREATE("Disconnected"),
NULL);
}
gpr_mu_unlock(&chand->mu);
GPR_TIMER_END("pick_subchannel", 0);
return false;
}