static void pf_shutdown(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
pending_pick *pp;
grpc_connected_subchannel *selected;
gpr_mu_lock(&p->mu);
selected = GET_SELECTED(p);
p->shutdown = 1;
pp = p->pending_picks;
p->pending_picks = NULL;
grpc_connectivity_state_set(
exec_ctx, &p->state_tracker, GRPC_CHANNEL_SHUTDOWN,
GRPC_ERROR_CREATE("Channel shutdown"), "shutdown");
/* cancel subscription */
if (selected != NULL) {
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, selected, NULL, NULL, &p->connectivity_changed);
} else if (p->num_subchannels > 0) {
grpc_subchannel_notify_on_state_change(
exec_ctx, p->subchannels[p->checking_subchannel], NULL, NULL,
&p->connectivity_changed);
}
gpr_mu_unlock(&p->mu);
while (pp != NULL) {
pending_pick *next = pp->next;
*pp->target = NULL;
grpc_exec_ctx_sched(exec_ctx, pp->on_complete, GRPC_ERROR_NONE, NULL);
gpr_free(pp);
pp = next;
}
}
void pf_shutdown(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
pick_first_lb_policy *p = (pick_first_lb_policy *)pol;
pending_pick *pp;
grpc_connected_subchannel *selected;
gpr_mu_lock(&p->mu);
selected = GET_SELECTED(p);
p->shutdown = 1;
pp = p->pending_picks;
p->pending_picks = NULL;
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
GRPC_CHANNEL_FATAL_FAILURE, "shutdown");
/* cancel subscription */
if (selected != NULL) {
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, selected, NULL, NULL, &p->connectivity_changed);
} else {
grpc_subchannel_notify_on_state_change(
exec_ctx, p->subchannels[p->checking_subchannel], NULL, NULL,
&p->connectivity_changed);
}
gpr_mu_unlock(&p->mu);
while (pp != NULL) {
pending_pick *next = pp->next;
*pp->target = NULL;
grpc_pollset_set_del_pollset(exec_ctx, &p->base.interested_parties,
pp->pollset);
grpc_exec_ctx_enqueue(exec_ctx, pp->on_complete, 1);
gpr_free(pp);
pp = next;
}
}
static void monitor_subchannel(grpc_exec_ctx *exec_ctx, void *arg,
bool iomgr_success) {
channel_data *chand = arg;
grpc_connectivity_state_set(exec_ctx, &chand->state_tracker,
chand->subchannel_connectivity,
"uchannel_monitor_subchannel");
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, chand->connected_subchannel, NULL,
&chand->subchannel_connectivity, &chand->connectivity_cb);
}
/* Destructor for channel_data */
static void cuc_destroy_channel_elem(grpc_exec_ctx *exec_ctx,
grpc_channel_element *elem) {
channel_data *chand = elem->channel_data;
/* cancel subscription */
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, chand->connected_subchannel, NULL, NULL,
&chand->connectivity_cb);
grpc_connectivity_state_destroy(exec_ctx, &chand->state_tracker);
gpr_mu_destroy(&chand->mu_state);
GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, chand->connected_subchannel,
"uchannel");
}
static void pf_connectivity_changed(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
pick_first_lb_policy *p = arg;
grpc_subchannel *selected_subchannel;
pending_pick *pp;
grpc_connected_subchannel *selected;
GRPC_ERROR_REF(error);
gpr_mu_lock(&p->mu);
selected = GET_SELECTED(p);
if (p->shutdown) {
gpr_mu_unlock(&p->mu);
GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "pick_first_connectivity");
GRPC_ERROR_UNREF(error);
return;
} else if (selected != NULL) {
if (p->checking_connectivity == GRPC_CHANNEL_TRANSIENT_FAILURE) {
/* if the selected channel goes bad, we're done */
p->checking_connectivity = GRPC_CHANNEL_SHUTDOWN;
}
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
p->checking_connectivity, GRPC_ERROR_REF(error),
"selected_changed");
if (p->checking_connectivity != GRPC_CHANNEL_SHUTDOWN) {
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, selected, p->base.interested_parties,
&p->checking_connectivity, &p->connectivity_changed);
} else {
GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "pick_first_connectivity");
}
} else {
loop:
switch (p->checking_connectivity) {
case GRPC_CHANNEL_READY:
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
GRPC_CHANNEL_READY, GRPC_ERROR_NONE,
"connecting_ready");
selected_subchannel = p->subchannels[p->checking_subchannel];
selected =
grpc_subchannel_get_connected_subchannel(selected_subchannel);
GPR_ASSERT(selected != NULL);
GRPC_CONNECTED_SUBCHANNEL_REF(selected, "picked_first");
/* drop the pick list: we are connected now */
GRPC_LB_POLICY_WEAK_REF(&p->base, "destroy_subchannels");
gpr_atm_rel_store(&p->selected, (gpr_atm)selected);
grpc_exec_ctx_sched(exec_ctx,
grpc_closure_create(destroy_subchannels, p),
GRPC_ERROR_NONE, NULL);
/* update any calls that were waiting for a pick */
while ((pp = p->pending_picks)) {
p->pending_picks = pp->next;
*pp->target = selected;
grpc_exec_ctx_sched(exec_ctx, pp->on_complete, GRPC_ERROR_NONE, NULL);
gpr_free(pp);
}
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, selected, p->base.interested_parties,
&p->checking_connectivity, &p->connectivity_changed);
break;
case GRPC_CHANNEL_TRANSIENT_FAILURE:
p->checking_subchannel =
(p->checking_subchannel + 1) % p->num_subchannels;
if (p->checking_subchannel == 0) {
/* only trigger transient failure when we've tried all alternatives */
grpc_connectivity_state_set(
exec_ctx, &p->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
GRPC_ERROR_REF(error), "connecting_transient_failure");
}
GRPC_ERROR_UNREF(error);
p->checking_connectivity = grpc_subchannel_check_connectivity(
p->subchannels[p->checking_subchannel], &error);
if (p->checking_connectivity == GRPC_CHANNEL_TRANSIENT_FAILURE) {
grpc_subchannel_notify_on_state_change(
exec_ctx, p->subchannels[p->checking_subchannel],
p->base.interested_parties, &p->checking_connectivity,
&p->connectivity_changed);
} else {
goto loop;
}
break;
case GRPC_CHANNEL_CONNECTING:
case GRPC_CHANNEL_IDLE:
grpc_connectivity_state_set(
exec_ctx, &p->state_tracker, GRPC_CHANNEL_CONNECTING,
GRPC_ERROR_REF(error), "connecting_changed");
grpc_subchannel_notify_on_state_change(
exec_ctx, p->subchannels[p->checking_subchannel],
p->base.interested_parties, &p->checking_connectivity,
&p->connectivity_changed);
break;
case GRPC_CHANNEL_SHUTDOWN:
p->num_subchannels--;
GPR_SWAP(grpc_subchannel *, p->subchannels[p->checking_subchannel],
p->subchannels[p->num_subchannels]);
GRPC_SUBCHANNEL_UNREF(exec_ctx, p->subchannels[p->num_subchannels],
"pick_first");
if (p->num_subchannels == 0) {
grpc_connectivity_state_set(
exec_ctx, &p->state_tracker, GRPC_CHANNEL_SHUTDOWN,
GRPC_ERROR_CREATE_REFERENCING("Pick first exhausted channels",
&error, 1),
"no_more_channels");
while ((pp = p->pending_picks)) {
p->pending_picks = pp->next;
*pp->target = NULL;
grpc_exec_ctx_sched(exec_ctx, pp->on_complete, GRPC_ERROR_NONE,
NULL);
gpr_free(pp);
}
GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base,
"pick_first_connectivity");
} else {
grpc_connectivity_state_set(
exec_ctx, &p->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
GRPC_ERROR_REF(error), "subchannel_failed");
p->checking_subchannel %= p->num_subchannels;
GRPC_ERROR_UNREF(error);
p->checking_connectivity = grpc_subchannel_check_connectivity(
p->subchannels[p->checking_subchannel], &error);
goto loop;
}
}
}
gpr_mu_unlock(&p->mu);
GRPC_ERROR_UNREF(error);
}
static void pf_connectivity_changed(grpc_exec_ctx *exec_ctx, void *arg,
int iomgr_success) {
pick_first_lb_policy *p = arg;
grpc_subchannel *selected_subchannel;
pending_pick *pp;
grpc_connected_subchannel *selected;
gpr_mu_lock(&p->mu);
selected = GET_SELECTED(p);
if (p->shutdown) {
gpr_mu_unlock(&p->mu);
GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "pick_first_connectivity");
return;
} else if (selected != NULL) {
if (p->checking_connectivity == GRPC_CHANNEL_TRANSIENT_FAILURE) {
/* if the selected channel goes bad, we're done */
p->checking_connectivity = GRPC_CHANNEL_FATAL_FAILURE;
}
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
p->checking_connectivity, "selected_changed");
if (p->checking_connectivity != GRPC_CHANNEL_FATAL_FAILURE) {
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, selected, &p->base.interested_parties,
&p->checking_connectivity, &p->connectivity_changed);
} else {
GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base, "pick_first_connectivity");
}
} else {
loop:
switch (p->checking_connectivity) {
case GRPC_CHANNEL_READY:
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
GRPC_CHANNEL_READY, "connecting_ready");
selected_subchannel = p->subchannels[p->checking_subchannel];
selected = grpc_subchannel_get_connected_subchannel(selected_subchannel);
GPR_ASSERT(selected != NULL);
gpr_atm_no_barrier_store(&p->selected, (gpr_atm)selected);
GRPC_CONNECTED_SUBCHANNEL_REF(selected, "picked_first");
/* drop the pick list: we are connected now */
GRPC_LB_POLICY_WEAK_REF(&p->base, "destroy_subchannels");
grpc_exec_ctx_enqueue(exec_ctx,
grpc_closure_create(destroy_subchannels, p), 1);
/* update any calls that were waiting for a pick */
while ((pp = p->pending_picks)) {
p->pending_picks = pp->next;
*pp->target = selected;
grpc_pollset_set_del_pollset(exec_ctx, &p->base.interested_parties,
pp->pollset);
grpc_exec_ctx_enqueue(exec_ctx, pp->on_complete, 1);
gpr_free(pp);
}
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, selected, &p->base.interested_parties,
&p->checking_connectivity, &p->connectivity_changed);
break;
case GRPC_CHANNEL_TRANSIENT_FAILURE:
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
GRPC_CHANNEL_TRANSIENT_FAILURE,
"connecting_transient_failure");
p->checking_subchannel =
(p->checking_subchannel + 1) % p->num_subchannels;
p->checking_connectivity = grpc_subchannel_check_connectivity(
p->subchannels[p->checking_subchannel]);
if (p->checking_connectivity == GRPC_CHANNEL_TRANSIENT_FAILURE) {
grpc_subchannel_notify_on_state_change(
exec_ctx, p->subchannels[p->checking_subchannel],
&p->base.interested_parties, &p->checking_connectivity,
&p->connectivity_changed);
} else {
goto loop;
}
break;
case GRPC_CHANNEL_CONNECTING:
case GRPC_CHANNEL_IDLE:
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
GRPC_CHANNEL_CONNECTING,
"connecting_changed");
grpc_subchannel_notify_on_state_change(
exec_ctx, p->subchannels[p->checking_subchannel],
&p->base.interested_parties, &p->checking_connectivity,
&p->connectivity_changed);
break;
case GRPC_CHANNEL_FATAL_FAILURE:
p->num_subchannels--;
GPR_SWAP(grpc_subchannel *, p->subchannels[p->checking_subchannel],
p->subchannels[p->num_subchannels]);
GRPC_SUBCHANNEL_UNREF(exec_ctx, p->subchannels[p->num_subchannels],
"pick_first");
if (p->num_subchannels == 0) {
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
GRPC_CHANNEL_FATAL_FAILURE,
"no_more_channels");
while ((pp = p->pending_picks)) {
p->pending_picks = pp->next;
*pp->target = NULL;
grpc_exec_ctx_enqueue(exec_ctx, pp->on_complete, 1);
gpr_free(pp);
}
GRPC_LB_POLICY_WEAK_UNREF(exec_ctx, &p->base,
"pick_first_connectivity");
} else {
grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
GRPC_CHANNEL_TRANSIENT_FAILURE,
"subchannel_failed");
p->checking_subchannel %= p->num_subchannels;
p->checking_connectivity = grpc_subchannel_check_connectivity(
p->subchannels[p->checking_subchannel]);
goto loop;
}
}
}
gpr_mu_unlock(&p->mu);
}
