Chiebot-Mirror
/
grpc
mirror of https://github.com/grpc/grpc.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

More cleanup in client_channel code.

Browse Source
pull/12297/head
Mark D. Roth 7 years ago
parent ca7084bced
commit b29296042a
1 changed files with 153 additions and 161 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 314
      src/core/ext/filters/client_channel/client_channel.c

314
src/core/ext/filters/client_channel/client_channel.c
Unescape View File

@ -1016,13 +1016,11 @@ static void create_subchannel_call_locked(grpc_exec_ctx *exec_ctx,
GRPC_ERROR_UNREF(error);
}
static void subchannel_ready_locked(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem,
grpc_error *error) {
// Invoked when a pick is completed, on both success or failure.
static void pick_done_locked(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
grpc_error *error) {
call_data *calld = (call_data *)elem->call_data;
channel_data *chand = (channel_data *)elem->channel_data;
grpc_polling_entity_del_from_pollset_set(exec_ctx, calld->pollent,
chand->interested_parties);
if (calld->connected_subchannel == NULL) {
// Failed to create subchannel.
GRPC_ERROR_UNREF(calld->error);
@ -1044,12 +1042,116 @@ static void subchannel_ready_locked(grpc_exec_ctx *exec_ctx,
GRPC_ERROR_UNREF(error);
}
/** Return true if subchannel is available immediately (in which case
subchannel_ready_locked() should not be called), or false otherwise (in
which case subchannel_ready_locked() should be called when the subchannel
is available). */
static bool pick_subchannel_locked(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem);
// A wrapper around pick_done_locked() that is used in cases where
// either (a) the pick was deferred pending a resolver result or (b) the
// pick was done asynchronously. Removes the call's polling entity from
// chand->interested_parties before invoking pick_done_locked().
static void async_pick_done_locked(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem, grpc_error *error) {
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
grpc_polling_entity_del_from_pollset_set(exec_ctx, calld->pollent,
chand->interested_parties);
pick_done_locked(exec_ctx, elem, error);
}
// Note: This runs under the client_channel combiner, but will NOT be
// holding the call combiner.
static void pick_callback_cancel_locked(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
grpc_call_element *elem = (grpc_call_element *)arg;
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
if (calld->lb_policy != NULL) {
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: cancelling pick from LB policy %p",
chand, calld, calld->lb_policy);
}
grpc_lb_policy_cancel_pick_locked(exec_ctx, calld->lb_policy,
&calld->connected_subchannel,
GRPC_ERROR_REF(error));
}
GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call, "pick_callback_cancel");
}
// Callback invoked by grpc_lb_policy_pick_locked() for async picks.
// Unrefs the LB policy and invokes async_pick_done_locked().
static void pick_callback_done_locked(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
grpc_call_element *elem = (grpc_call_element *)arg;
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed asynchronously",
chand, calld);
}
GPR_ASSERT(calld->lb_policy != NULL);
GRPC_LB_POLICY_UNREF(exec_ctx, calld->lb_policy, "pick_subchannel");
calld->lb_policy = NULL;
async_pick_done_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
}
// Takes a ref to chand->lb_policy and calls grpc_lb_policy_pick_locked().
// If the pick was completed synchronously, unrefs the LB policy and
// returns true.
static bool pick_callback_start_locked(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem) {
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: starting pick on lb_policy=%p",
chand, calld, chand->lb_policy);
}
apply_service_config_to_call_locked(exec_ctx, elem);
// If the application explicitly set wait_for_ready, use that.
// Otherwise, if the service config specified a value for this
// method, use that.
uint32_t initial_metadata_flags =
calld->initial_metadata_batch->payload->send_initial_metadata
.send_initial_metadata_flags;
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->method_params != NULL &&
calld->method_params->wait_for_ready != WAIT_FOR_READY_UNSET;
if (!wait_for_ready_set_from_api && wait_for_ready_set_from_service_config) {
if (calld->method_params->wait_for_ready == WAIT_FOR_READY_TRUE) {
initial_metadata_flags |= GRPC_INITIAL_METADATA_WAIT_FOR_READY;
} else {
initial_metadata_flags &= ~GRPC_INITIAL_METADATA_WAIT_FOR_READY;
}
}
const grpc_lb_policy_pick_args inputs = {
calld->initial_metadata_batch->payload->send_initial_metadata
.send_initial_metadata,
initial_metadata_flags, &calld->lb_token_mdelem};
// Keep a ref to the LB policy in calld while the pick is pending.
GRPC_LB_POLICY_REF(chand->lb_policy, "pick_subchannel");
calld->lb_policy = chand->lb_policy;
GRPC_CLOSURE_INIT(&calld->lb_pick_closure, pick_callback_done_locked, elem,
grpc_combiner_scheduler(chand->combiner));
const bool pick_done = grpc_lb_policy_pick_locked(
exec_ctx, chand->lb_policy, &inputs, &calld->connected_subchannel,
calld->subchannel_call_context, NULL, &calld->lb_pick_closure);
if (pick_done) {
/* synchronous grpc_lb_policy_pick call. Unref the LB policy. */
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed synchronously",
chand, calld);
}
GRPC_LB_POLICY_UNREF(exec_ctx, calld->lb_policy, "pick_subchannel");
calld->lb_policy = NULL;
} else {
GRPC_CALL_STACK_REF(calld->owning_call, "pick_callback_cancel");
grpc_call_combiner_set_notify_on_cancel(
exec_ctx, calld->call_combiner,
GRPC_CLOSURE_INIT(&calld->lb_pick_cancel_closure,
pick_callback_cancel_locked, elem,
grpc_combiner_scheduler(chand->combiner)));
}
return pick_done;
}
typedef struct {
grpc_call_element *elem;
@ -1069,17 +1171,17 @@ static void pick_after_resolver_result_cancel_locked(grpc_exec_ctx *exec_ctx,
gpr_free(args);
return;
}
args->finished = true;
grpc_call_element *elem = args->elem;
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
// If we don't yet have a resolver result, then a closure for
// pick_after_resolver_result_done_locked() will have been added to
// chand->waiting_for_resolver_result_closures, and it may not be invoked
// until after this call has been destroyed. We mark the operation as
// finished, so that when pick_after_resolver_result_done_locked()
// is called, it will be a no-op. We also immediately invoke
// subchannel_ready_locked() to propagate the error back to the caller.
// async_pick_done_locked() to propagate the error back to the caller.
args->finished = true;
grpc_call_element *elem = args->elem;
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG,
"chand=%p calld=%p: cancelling pick waiting for resolver result",
@ -1087,12 +1189,12 @@ static void pick_after_resolver_result_cancel_locked(grpc_exec_ctx *exec_ctx,
}
// Note: Although we are not in the call combiner here, we are
// basically stealing the call combiner from the pending pick, so
// it's safe to call subchannel_ready_locked() here -- we are
// it's safe to call async_pick_done_locked() here -- we are
// essentially calling it here instead of calling it in
// pick_after_resolver_result_done_locked().
subchannel_ready_locked(exec_ctx, elem,
GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
"Pick cancelled", &error, 1));
async_pick_done_locked(exec_ctx, elem,
GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
"Pick cancelled", &error, 1));
}
static void pick_after_resolver_result_done_locked(grpc_exec_ctx *exec_ctx,
@ -1117,14 +1219,19 @@ static void pick_after_resolver_result_done_locked(grpc_exec_ctx *exec_ctx,
gpr_log(GPR_DEBUG, "chand=%p calld=%p: resolver failed to return data",
chand, calld);
}
subchannel_ready_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
async_pick_done_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
} else {
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: resolver returned, doing pick",
chand, calld);
}
if (pick_subchannel_locked(exec_ctx, elem)) {
subchannel_ready_locked(exec_ctx, elem, GRPC_ERROR_NONE);
if (pick_callback_start_locked(exec_ctx, elem)) {
// Even if the LB policy returns a result synchronously, we have
// already added our polling entity to chand->interested_parties
// in order to wait for the resolver result, so we need to
// remove it here. Therefore, we call async_pick_done_locked()
// instead of pick_done_locked().
async_pick_done_locked(exec_ctx, elem, GRPC_ERROR_NONE);
}
}
}
@ -1152,154 +1259,38 @@ static void pick_after_resolver_result_start_locked(grpc_exec_ctx *exec_ctx,
grpc_combiner_scheduler(chand->combiner)));
}
// Note: This runs under the client_channel combiner, but will NOT be
// holding the call combiner.
static void pick_callback_cancel_locked(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
grpc_call_element *elem = (grpc_call_element *)arg;
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
if (error != GRPC_ERROR_NONE && calld->lb_policy != NULL) {
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: cancelling pick from LB policy %p",
chand, calld, calld->lb_policy);
}
grpc_lb_policy_cancel_pick_locked(exec_ctx, calld->lb_policy,
&calld->connected_subchannel,
GRPC_ERROR_REF(error));
}
GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call, "pick_callback_cancel");
}
// Callback invoked by grpc_lb_policy_pick_locked() for async picks.
// Unrefs the LB policy and invokes subchannel_ready_locked().
static void pick_callback_done_locked(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
static void start_pick_locked(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *ignored) {
grpc_call_element *elem = (grpc_call_element *)arg;
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed asynchronously",
chand, calld);
}
GPR_ASSERT(calld->lb_policy != NULL);
GRPC_LB_POLICY_UNREF(exec_ctx, calld->lb_policy, "pick_subchannel");
calld->lb_policy = NULL;
subchannel_ready_locked(exec_ctx, elem, GRPC_ERROR_REF(error));
}
// Takes a ref to chand->lb_policy and calls grpc_lb_policy_pick_locked().
// If the pick was completed synchronously, unrefs the LB policy and
// returns true.
static bool pick_callback_start_locked(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem,
const grpc_lb_policy_pick_args *inputs) {
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: starting pick on lb_policy=%p",
chand, calld, chand->lb_policy);
}
// Keep a ref to the LB policy in calld while the pick is pending.
GRPC_LB_POLICY_REF(chand->lb_policy, "pick_subchannel");
calld->lb_policy = chand->lb_policy;
GRPC_CLOSURE_INIT(&calld->lb_pick_closure, pick_callback_done_locked, elem,
grpc_combiner_scheduler(chand->combiner));
const bool pick_done = grpc_lb_policy_pick_locked(
exec_ctx, chand->lb_policy, inputs, &calld->connected_subchannel,
calld->subchannel_call_context, NULL, &calld->lb_pick_closure);
if (pick_done) {
/* synchronous grpc_lb_policy_pick call. Unref the LB policy. */
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: pick completed synchronously",
chand, calld);
GPR_ASSERT(calld->connected_subchannel == NULL);
if (chand->lb_policy != NULL) {
// We already have an LB policy, so ask it for a pick.
if (pick_callback_start_locked(exec_ctx, elem)) {
// Pick completed synchronously.
pick_done_locked(exec_ctx, elem, GRPC_ERROR_NONE);
return;
}
GRPC_LB_POLICY_UNREF(exec_ctx, calld->lb_policy, "pick_subchannel");
calld->lb_policy = NULL;
} else {
GRPC_CALL_STACK_REF(calld->owning_call, "pick_callback_cancel");
grpc_call_combiner_set_notify_on_cancel(
exec_ctx, calld->call_combiner,
GRPC_CLOSURE_INIT(&calld->lb_pick_cancel_closure,
pick_callback_cancel_locked, elem,
grpc_combiner_scheduler(chand->combiner)));
}
return pick_done;
}
static bool pick_subchannel_locked(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem) {
GPR_TIMER_BEGIN("pick_subchannel", 0);
channel_data *chand = (channel_data *)elem->channel_data;
call_data *calld = (call_data *)elem->call_data;
bool pick_done = false;
if (chand->lb_policy != NULL) {
apply_service_config_to_call_locked(exec_ctx, elem);
// If the application explicitly set wait_for_ready, use that.
// Otherwise, if the service config specified a value for this
// method, use that.
uint32_t initial_metadata_flags =
calld->initial_metadata_batch->payload->send_initial_metadata
.send_initial_metadata_flags;
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->method_params != NULL &&
calld->method_params->wait_for_ready != WAIT_FOR_READY_UNSET;
if (!wait_for_ready_set_from_api &&
wait_for_ready_set_from_service_config) {
if (calld->method_params->wait_for_ready == WAIT_FOR_READY_TRUE) {
initial_metadata_flags |= GRPC_INITIAL_METADATA_WAIT_FOR_READY;
} else {
initial_metadata_flags &= ~GRPC_INITIAL_METADATA_WAIT_FOR_READY;
}
// We do not yet have an LB policy, so wait for a resolver result.
if (chand->resolver == NULL) {
pick_done_locked(exec_ctx, elem,
GRPC_ERROR_CREATE_FROM_STATIC_STRING("Disconnected"));
return;
}
const grpc_lb_policy_pick_args inputs = {
calld->initial_metadata_batch->payload->send_initial_metadata
.send_initial_metadata,
initial_metadata_flags, &calld->lb_token_mdelem};
pick_done = pick_callback_start_locked(exec_ctx, elem, &inputs);
} else if (chand->resolver != NULL) {
if (!chand->started_resolving) {
start_resolving_locked(exec_ctx, chand);
}
pick_after_resolver_result_start_locked(exec_ctx, elem);
} else {
subchannel_ready_locked(
exec_ctx, elem, GRPC_ERROR_CREATE_FROM_STATIC_STRING("Disconnected"));
}
GPR_TIMER_END("pick_subchannel", 0);
return pick_done;
}
static void start_pick_locked(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error_ignored) {
GPR_TIMER_BEGIN("start_pick_locked", 0);
grpc_call_element *elem = (grpc_call_element *)arg;
call_data *calld = (call_data *)elem->call_data;
channel_data *chand = (channel_data *)elem->channel_data;
GPR_ASSERT(calld->connected_subchannel == NULL);
if (pick_subchannel_locked(exec_ctx, elem)) {
// Pick was returned synchronously.
if (calld->connected_subchannel == NULL) {
GRPC_ERROR_UNREF(calld->error);
calld->error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
"Call dropped by load balancing policy");
waiting_for_pick_batches_fail(exec_ctx, elem,
GRPC_ERROR_REF(calld->error));
} else {
// Create subchannel call.
create_subchannel_call_locked(exec_ctx, elem, GRPC_ERROR_NONE);
}
} else {
// Pick will be done asynchronously. Add the call's polling entity to
// the channel's interested_parties, so that I/O for the resolver
// and LB policy can be done under it.
grpc_polling_entity_add_to_pollset_set(exec_ctx, calld->pollent,
chand->interested_parties);
}
GPR_TIMER_END("start_pick_locked", 0);
// We need to wait for either a resolver result or for an async result
// from the LB policy. Add the polling entity from call_data to the
// channel_data's interested_parties, so that the I/O of the LB policy
// and resolver can be done under it. The polling entity will be
// removed in async_pick_done_locked().
grpc_polling_entity_add_to_pollset_set(exec_ctx, calld->pollent,
chand->interested_parties);
}
static void on_complete(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
@ -1394,7 +1385,8 @@ static void cc_start_transport_stream_op_batch(
// combiner to start a pick.
if (batch->send_initial_metadata) {
if (GRPC_TRACER_ON(grpc_client_channel_trace)) {
gpr_log(GPR_DEBUG, "chand=%p calld=%p: entering combiner", chand, calld);
gpr_log(GPR_DEBUG, "chand=%p calld=%p: entering client_channel combiner",
chand, calld);
}
GRPC_CLOSURE_SCHED(
exec_ctx,

Write Preview
Loading…
Cancel
Save