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gerrit-public.fairphone.software / platform / external / grpc-grpc / 98cdf3b3e61c2e5db5b7b945e471f2c898faab33 / . / src / core / ext / client_channel / subchannel.c
blob: 09c68a91dd8e73182c60f3727f8aa4c9fefa511a [file] [log] [blame]
/*
*
* Copyright 2015, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include "src/core/ext/client_channel/subchannel.h"
#include <limits.h>
#include <string.h>
#include <grpc/support/alloc.h>
#include <grpc/support/avl.h>
#include <grpc/support/string_util.h>
#include "src/core/ext/client_channel/client_channel.h"
#include "src/core/ext/client_channel/initial_connect_string.h"
#include "src/core/ext/client_channel/parse_address.h"
#include "src/core/ext/client_channel/proxy_mapper_registry.h"
#include "src/core/ext/client_channel/subchannel_index.h"
#include "src/core/ext/client_channel/uri_parser.h"
#include "src/core/lib/channel/channel_args.h"
#include "src/core/lib/channel/connected_channel.h"
#include "src/core/lib/iomgr/sockaddr_utils.h"
#include "src/core/lib/iomgr/timer.h"
#include "src/core/lib/profiling/timers.h"
#include "src/core/lib/slice/slice_internal.h"
#include "src/core/lib/support/backoff.h"
#include "src/core/lib/surface/channel.h"
#include "src/core/lib/surface/channel_init.h"
#include "src/core/lib/transport/connectivity_state.h"
#define INTERNAL_REF_BITS 16
#define STRONG_REF_MASK (~(gpr_atm)((1 << INTERNAL_REF_BITS) - 1))
#define GRPC_SUBCHANNEL_MIN_CONNECT_TIMEOUT_SECONDS 20
#define GRPC_SUBCHANNEL_INITIAL_CONNECT_BACKOFF_SECONDS 1
#define GRPC_SUBCHANNEL_RECONNECT_BACKOFF_MULTIPLIER 1.6
#define GRPC_SUBCHANNEL_RECONNECT_MAX_BACKOFF_SECONDS 120
#define GRPC_SUBCHANNEL_RECONNECT_JITTER 0.2
#define GET_CONNECTED_SUBCHANNEL(subchannel, barrier) \
((grpc_connected_subchannel *)(gpr_atm_##barrier##_load( \
&(subchannel)->connected_subchannel)))
typedef struct {
grpc_closure closure;
grpc_subchannel *subchannel;
grpc_connectivity_state connectivity_state;
} state_watcher;
typedef struct external_state_watcher {
grpc_subchannel *subchannel;
grpc_pollset_set *pollset_set;
grpc_closure *notify;
grpc_closure closure;
struct external_state_watcher *next;
struct external_state_watcher *prev;
} external_state_watcher;
struct grpc_subchannel {
grpc_connector *connector;
/** refcount
- lower INTERNAL_REF_BITS bits are for internal references:
these do not keep the subchannel open.
- upper remaining bits are for public references: these do
keep the subchannel open */
gpr_atm ref_pair;
/** non-transport related channel filters */
const grpc_channel_filter **filters;
size_t num_filters;
/** channel arguments */
grpc_channel_args *args;
grpc_subchannel_key *key;
/** initial string to send to peer */
grpc_slice initial_connect_string;
/** set during connection */
grpc_connect_out_args connecting_result;
/** callback for connection finishing */
grpc_closure connected;
/** callback for our alarm */
grpc_closure on_alarm;
/** pollset_set tracking who's interested in a connection
being setup */
grpc_pollset_set *pollset_set;
/** active connection, or null; of type grpc_connected_subchannel */
gpr_atm connected_subchannel;
/** mutex protecting remaining elements */
gpr_mu mu;
/** have we seen a disconnection? */
bool disconnected;
/** are we connecting */
bool connecting;
/** connectivity state tracking */
grpc_connectivity_state_tracker state_tracker;
external_state_watcher root_external_state_watcher;
/** next connect attempt time */
gpr_timespec next_attempt;
/** backoff state */
gpr_backoff backoff_state;
/** do we have an active alarm? */
bool have_alarm;
/** have we started the backoff loop */
bool backoff_begun;
/** our alarm */
grpc_timer alarm;
};
struct grpc_subchannel_call {
grpc_connected_subchannel *connection;
};
#define SUBCHANNEL_CALL_TO_CALL_STACK(call) ((grpc_call_stack *)((call) + 1))
#define CHANNEL_STACK_FROM_CONNECTION(con) ((grpc_channel_stack *)(con))
#define CALLSTACK_TO_SUBCHANNEL_CALL(callstack) \
(((grpc_subchannel_call *)(callstack)) - 1)
static void subchannel_connected(grpc_exec_ctx *exec_ctx, void *subchannel,
grpc_error *error);
#ifdef GRPC_STREAM_REFCOUNT_DEBUG
#define REF_REASON reason
#define REF_LOG(name, p) \
gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "%s: %p ref %d -> %d %s", \
(name), (p), (p)->refs.count, (p)->refs.count + 1, reason)
#define UNREF_LOG(name, p) \
gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG, "%s: %p unref %d -> %d %s", \
(name), (p), (p)->refs.count, (p)->refs.count - 1, reason)
#define REF_MUTATE_EXTRA_ARGS \
GRPC_SUBCHANNEL_REF_EXTRA_ARGS, const char *purpose
#define REF_MUTATE_PURPOSE(x) , file, line, reason, x
#else
#define REF_REASON ""
#define REF_LOG(name, p) \
do { \
} while (0)
#define UNREF_LOG(name, p) \
do { \
} while (0)
#define REF_MUTATE_EXTRA_ARGS
#define REF_MUTATE_PURPOSE(x)
#endif
/*
* connection implementation
*/
static void connection_destroy(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
grpc_connected_subchannel *c = arg;
grpc_channel_stack_destroy(exec_ctx, CHANNEL_STACK_FROM_CONNECTION(c));
gpr_free(c);
}
grpc_connected_subchannel *grpc_connected_subchannel_ref(
grpc_connected_subchannel *c GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
GRPC_CHANNEL_STACK_REF(CHANNEL_STACK_FROM_CONNECTION(c), REF_REASON);
return c;
}
void grpc_connected_subchannel_unref(grpc_exec_ctx *exec_ctx,
grpc_connected_subchannel *c
GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
GRPC_CHANNEL_STACK_UNREF(exec_ctx, CHANNEL_STACK_FROM_CONNECTION(c),
REF_REASON);
}
/*
* grpc_subchannel implementation
*/
static void subchannel_destroy(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
grpc_subchannel *c = arg;
gpr_free((void *)c->filters);
grpc_channel_args_destroy(exec_ctx, c->args);
grpc_slice_unref_internal(exec_ctx, c->initial_connect_string);
grpc_connectivity_state_destroy(exec_ctx, &c->state_tracker);
grpc_connector_unref(exec_ctx, c->connector);
grpc_pollset_set_destroy(exec_ctx, c->pollset_set);
grpc_subchannel_key_destroy(exec_ctx, c->key);
gpr_free(c);
}
static gpr_atm ref_mutate(grpc_subchannel *c, gpr_atm delta,
int barrier REF_MUTATE_EXTRA_ARGS) {
gpr_atm old_val = barrier ? gpr_atm_full_fetch_add(&c->ref_pair, delta)
: gpr_atm_no_barrier_fetch_add(&c->ref_pair, delta);
#ifdef GRPC_STREAM_REFCOUNT_DEBUG
gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
"SUBCHANNEL: %p %s 0x%08" PRIxPTR " -> 0x%08" PRIxPTR " [%s]", c,
purpose, old_val, old_val + delta, reason);
#endif
return old_val;
}
grpc_subchannel *grpc_subchannel_ref(
grpc_subchannel *c GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
gpr_atm old_refs;
old_refs = ref_mutate(c, (1 << INTERNAL_REF_BITS),
0 REF_MUTATE_PURPOSE("STRONG_REF"));
GPR_ASSERT((old_refs & STRONG_REF_MASK) != 0);
return c;
}
grpc_subchannel *grpc_subchannel_weak_ref(
grpc_subchannel *c GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
gpr_atm old_refs;
old_refs = ref_mutate(c, 1, 0 REF_MUTATE_PURPOSE("WEAK_REF"));
GPR_ASSERT(old_refs != 0);
return c;
}
grpc_subchannel *grpc_subchannel_ref_from_weak_ref(
grpc_subchannel *c GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
if (!c) return NULL;
for (;;) {
gpr_atm old_refs = gpr_atm_acq_load(&c->ref_pair);
if (old_refs >= (1 << INTERNAL_REF_BITS)) {
gpr_atm new_refs = old_refs + (1 << INTERNAL_REF_BITS);
if (gpr_atm_rel_cas(&c->ref_pair, old_refs, new_refs)) {
return c;
}
} else {
return NULL;
}
}
}
static void disconnect(grpc_exec_ctx *exec_ctx, grpc_subchannel *c) {
grpc_connected_subchannel *con;
grpc_subchannel_index_unregister(exec_ctx, c->key, c);
gpr_mu_lock(&c->mu);
GPR_ASSERT(!c->disconnected);
c->disconnected = true;
grpc_connector_shutdown(exec_ctx, c->connector,
GRPC_ERROR_CREATE("Subchannel disconnected"));
con = GET_CONNECTED_SUBCHANNEL(c, no_barrier);
if (con != NULL) {
GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, con, "connection");
gpr_atm_no_barrier_store(&c->connected_subchannel, (gpr_atm)0xdeadbeef);
}
gpr_mu_unlock(&c->mu);
}
void grpc_subchannel_unref(grpc_exec_ctx *exec_ctx,
grpc_subchannel *c GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
gpr_atm old_refs;
old_refs = ref_mutate(c, (gpr_atm)1 - (gpr_atm)(1 << INTERNAL_REF_BITS),
1 REF_MUTATE_PURPOSE("STRONG_UNREF"));
if ((old_refs & STRONG_REF_MASK) == (1 << INTERNAL_REF_BITS)) {
disconnect(exec_ctx, c);
}
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "strong-unref");
}
void grpc_subchannel_weak_unref(grpc_exec_ctx *exec_ctx,
grpc_subchannel *c
GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
gpr_atm old_refs;
old_refs = ref_mutate(c, -(gpr_atm)1, 1 REF_MUTATE_PURPOSE("WEAK_UNREF"));
if (old_refs == 1) {
grpc_closure_sched(exec_ctx, grpc_closure_create(subchannel_destroy, c,
grpc_schedule_on_exec_ctx),
GRPC_ERROR_NONE);
}
}
grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
grpc_connector *connector,
const grpc_subchannel_args *args) {
grpc_subchannel_key *key = grpc_subchannel_key_create(connector, args);
grpc_subchannel *c = grpc_subchannel_index_find(exec_ctx, key);
if (c) {
grpc_subchannel_key_destroy(exec_ctx, key);
return c;
}
c = gpr_malloc(sizeof(*c));
memset(c, 0, sizeof(*c));
c->key = key;
gpr_atm_no_barrier_store(&c->ref_pair, 1 << INTERNAL_REF_BITS);
c->connector = connector;
grpc_connector_ref(c->connector);
c->num_filters = args->filter_count;
if (c->num_filters > 0) {
c->filters = gpr_malloc(sizeof(grpc_channel_filter *) * c->num_filters);
memcpy((void *)c->filters, args->filters,
sizeof(grpc_channel_filter *) * c->num_filters);
} else {
c->filters = NULL;
}
c->pollset_set = grpc_pollset_set_create();
grpc_resolved_address *addr = gpr_malloc(sizeof(*addr));
grpc_get_subchannel_address_arg(args->args, addr);
grpc_set_initial_connect_string(&addr, &c->initial_connect_string);
grpc_resolved_address *new_address = NULL;
grpc_channel_args *new_args = NULL;
if (grpc_proxy_mappers_map_address(exec_ctx, addr, args->args, &new_address,
&new_args)) {
GPR_ASSERT(new_address != NULL);
gpr_free(addr);
addr = new_address;
if (new_args != NULL) c->args = new_args;
}
if (c->args == NULL) {
static const char *keys_to_remove[] = {GRPC_ARG_SUBCHANNEL_ADDRESS};
grpc_arg new_arg = grpc_create_subchannel_address_arg(addr);
c->args = grpc_channel_args_copy_and_add_and_remove(
args->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &new_arg,
1);
gpr_free(new_arg.value.string);
}
gpr_free(addr);
c->root_external_state_watcher.next = c->root_external_state_watcher.prev =
&c->root_external_state_watcher;
grpc_closure_init(&c->connected, subchannel_connected, c,
grpc_schedule_on_exec_ctx);
grpc_connectivity_state_init(&c->state_tracker, GRPC_CHANNEL_IDLE,
"subchannel");
int initial_backoff_ms =
GRPC_SUBCHANNEL_INITIAL_CONNECT_BACKOFF_SECONDS * 1000;
int max_backoff_ms = GRPC_SUBCHANNEL_RECONNECT_MAX_BACKOFF_SECONDS * 1000;
int min_backoff_ms = GRPC_SUBCHANNEL_MIN_CONNECT_TIMEOUT_SECONDS * 1000;
bool fixed_reconnect_backoff = false;
if (c->args) {
for (size_t i = 0; i < c->args->num_args; i++) {
if (0 == strcmp(c->args->args[i].key,
"grpc.testing.fixed_reconnect_backoff_ms")) {
GPR_ASSERT(c->args->args[i].type == GRPC_ARG_INTEGER);
fixed_reconnect_backoff = true;
initial_backoff_ms = min_backoff_ms = max_backoff_ms =
grpc_channel_arg_get_integer(
&c->args->args[i],
(grpc_integer_options){initial_backoff_ms, 100, INT_MAX});
} else if (0 == strcmp(c->args->args[i].key,
GRPC_ARG_MAX_RECONNECT_BACKOFF_MS)) {
fixed_reconnect_backoff = false;
max_backoff_ms = grpc_channel_arg_get_integer(
&c->args->args[i],
(grpc_integer_options){max_backoff_ms, 100, INT_MAX});
} else if (0 == strcmp(c->args->args[i].key,
GRPC_ARG_INITIAL_RECONNECT_BACKOFF_MS)) {
fixed_reconnect_backoff = false;
initial_backoff_ms = grpc_channel_arg_get_integer(
&c->args->args[i],
(grpc_integer_options){initial_backoff_ms, 100, INT_MAX});
}
}
}
gpr_backoff_init(
&c->backoff_state, initial_backoff_ms,
fixed_reconnect_backoff ? 1.0
: GRPC_SUBCHANNEL_RECONNECT_BACKOFF_MULTIPLIER,
fixed_reconnect_backoff ? 0.0 : GRPC_SUBCHANNEL_RECONNECT_JITTER,
min_backoff_ms, max_backoff_ms);
gpr_mu_init(&c->mu);
return grpc_subchannel_index_register(exec_ctx, key, c);
}
static void continue_connect_locked(grpc_exec_ctx *exec_ctx,
grpc_subchannel *c) {
grpc_connect_in_args args;
args.interested_parties = c->pollset_set;
args.deadline = c->next_attempt;
args.channel_args = c->args;
args.initial_connect_string = c->initial_connect_string;
grpc_connectivity_state_set(exec_ctx, &c->state_tracker,
GRPC_CHANNEL_CONNECTING, GRPC_ERROR_NONE,
"state_change");
grpc_connector_connect(exec_ctx, c->connector, &args, &c->connecting_result,
&c->connected);
}
grpc_connectivity_state grpc_subchannel_check_connectivity(grpc_subchannel *c,
grpc_error **error) {
grpc_connectivity_state state;
gpr_mu_lock(&c->mu);
state = grpc_connectivity_state_get(&c->state_tracker, error);
gpr_mu_unlock(&c->mu);
return state;
}
static void on_external_state_watcher_done(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
external_state_watcher *w = arg;
grpc_closure *follow_up = w->notify;
if (w->pollset_set != NULL) {
grpc_pollset_set_del_pollset_set(exec_ctx, w->subchannel->pollset_set,
w->pollset_set);
}
gpr_mu_lock(&w->subchannel->mu);
w->next->prev = w->prev;
w->prev->next = w->next;
gpr_mu_unlock(&w->subchannel->mu);
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, w->subchannel, "external_state_watcher");
gpr_free(w);
follow_up->cb(exec_ctx, follow_up->cb_arg, error);
}
static void on_alarm(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
grpc_subchannel *c = arg;
gpr_mu_lock(&c->mu);
c->have_alarm = false;
if (c->disconnected) {
error = GRPC_ERROR_CREATE_REFERENCING("Disconnected", &error, 1);
} else {
GRPC_ERROR_REF(error);
}
if (error == GRPC_ERROR_NONE) {
gpr_log(GPR_INFO, "Failed to connect to channel, retrying");
c->next_attempt =
gpr_backoff_step(&c->backoff_state, gpr_now(GPR_CLOCK_MONOTONIC));
continue_connect_locked(exec_ctx, c);
gpr_mu_unlock(&c->mu);
} else {
gpr_mu_unlock(&c->mu);
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "connecting");
}
GRPC_ERROR_UNREF(error);
}
static void maybe_start_connecting_locked(grpc_exec_ctx *exec_ctx,
grpc_subchannel *c) {
if (c->disconnected) {
/* Don't try to connect if we're already disconnected */
return;
}
if (c->connecting) {
/* Already connecting: don't restart */
return;
}
if (GET_CONNECTED_SUBCHANNEL(c, no_barrier) != NULL) {
/* Already connected: don't restart */
return;
}
if (!grpc_connectivity_state_has_watchers(&c->state_tracker)) {
/* Nobody is interested in connecting: so don't just yet */
return;
}
c->connecting = true;
GRPC_SUBCHANNEL_WEAK_REF(c, "connecting");
gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
if (!c->backoff_begun) {
c->backoff_begun = true;
c->next_attempt = gpr_backoff_begin(&c->backoff_state, now);
continue_connect_locked(exec_ctx, c);
} else {
GPR_ASSERT(!c->have_alarm);
c->have_alarm = true;
gpr_timespec time_til_next = gpr_time_sub(c->next_attempt, now);
if (gpr_time_cmp(time_til_next, gpr_time_0(time_til_next.clock_type)) <=
0) {
gpr_log(GPR_INFO, "Retry immediately");
} else {
gpr_log(GPR_INFO, "Retry in %" PRId64 ".%09d seconds",
time_til_next.tv_sec, time_til_next.tv_nsec);
}
grpc_closure_init(&c->on_alarm, on_alarm, c, grpc_schedule_on_exec_ctx);
grpc_timer_init(exec_ctx, &c->alarm, c->next_attempt, &c->on_alarm, now);
}
}
void grpc_subchannel_notify_on_state_change(
grpc_exec_ctx *exec_ctx, grpc_subchannel *c,
grpc_pollset_set *interested_parties, grpc_connectivity_state *state,
grpc_closure *notify) {
external_state_watcher *w;
if (state == NULL) {
gpr_mu_lock(&c->mu);
for (w = c->root_external_state_watcher.next;
w != &c->root_external_state_watcher; w = w->next) {
if (w->notify == notify) {
grpc_connectivity_state_notify_on_state_change(
exec_ctx, &c->state_tracker, NULL, &w->closure);
}
}
gpr_mu_unlock(&c->mu);
} else {
w = gpr_malloc(sizeof(*w));
w->subchannel = c;
w->pollset_set = interested_parties;
w->notify = notify;
grpc_closure_init(&w->closure, on_external_state_watcher_done, w,
grpc_schedule_on_exec_ctx);
if (interested_parties != NULL) {
grpc_pollset_set_add_pollset_set(exec_ctx, c->pollset_set,
interested_parties);
}
GRPC_SUBCHANNEL_WEAK_REF(c, "external_state_watcher");
gpr_mu_lock(&c->mu);
w->next = &c->root_external_state_watcher;
w->prev = w->next->prev;
w->next->prev = w->prev->next = w;
grpc_connectivity_state_notify_on_state_change(exec_ctx, &c->state_tracker,
state, &w->closure);
maybe_start_connecting_locked(exec_ctx, c);
gpr_mu_unlock(&c->mu);
}
}
void grpc_connected_subchannel_process_transport_op(
grpc_exec_ctx *exec_ctx, grpc_connected_subchannel *con,
grpc_transport_op *op) {
grpc_channel_stack *channel_stack = CHANNEL_STACK_FROM_CONNECTION(con);
grpc_channel_element *top_elem = grpc_channel_stack_element(channel_stack, 0);
top_elem->filter->start_transport_op(exec_ctx, top_elem, op);
}
static void subchannel_on_child_state_changed(grpc_exec_ctx *exec_ctx, void *p,
grpc_error *error) {
state_watcher *sw = p;
grpc_subchannel *c = sw->subchannel;
gpr_mu *mu = &c->mu;
gpr_mu_lock(mu);
/* if we failed just leave this closure */
if (sw->connectivity_state == GRPC_CHANNEL_TRANSIENT_FAILURE) {
/* any errors on a subchannel ==> we're done, create a new one */
sw->connectivity_state = GRPC_CHANNEL_SHUTDOWN;
}
grpc_connectivity_state_set(exec_ctx, &c->state_tracker,
sw->connectivity_state, GRPC_ERROR_REF(error),
"reflect_child");
if (sw->connectivity_state != GRPC_CHANNEL_SHUTDOWN) {
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, GET_CONNECTED_SUBCHANNEL(c, no_barrier), NULL,
&sw->connectivity_state, &sw->closure);
GRPC_SUBCHANNEL_WEAK_REF(c, "state_watcher");
sw = NULL;
}
gpr_mu_unlock(mu);
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "state_watcher");
gpr_free(sw);
}
static void connected_subchannel_state_op(grpc_exec_ctx *exec_ctx,
grpc_connected_subchannel *con,
grpc_pollset_set *interested_parties,
grpc_connectivity_state *state,
grpc_closure *closure) {
grpc_transport_op *op = grpc_make_transport_op(NULL);
grpc_channel_element *elem;
op->connectivity_state = state;
op->on_connectivity_state_change = closure;
op->bind_pollset_set = interested_parties;
elem = grpc_channel_stack_element(CHANNEL_STACK_FROM_CONNECTION(con), 0);
elem->filter->start_transport_op(exec_ctx, elem, op);
}
void grpc_connected_subchannel_notify_on_state_change(
grpc_exec_ctx *exec_ctx, grpc_connected_subchannel *con,
grpc_pollset_set *interested_parties, grpc_connectivity_state *state,
grpc_closure *closure) {
connected_subchannel_state_op(exec_ctx, con, interested_parties, state,
closure);
}
void grpc_connected_subchannel_ping(grpc_exec_ctx *exec_ctx,
grpc_connected_subchannel *con,
grpc_closure *closure) {
grpc_transport_op *op = grpc_make_transport_op(NULL);
grpc_channel_element *elem;
op->send_ping = closure;
elem = grpc_channel_stack_element(CHANNEL_STACK_FROM_CONNECTION(con), 0);
elem->filter->start_transport_op(exec_ctx, elem, op);
}
static void publish_transport_locked(grpc_exec_ctx *exec_ctx,
grpc_subchannel *c) {
grpc_connected_subchannel *con;
grpc_channel_stack *stk;
state_watcher *sw_subchannel;
/* construct channel stack */
grpc_channel_stack_builder *builder = grpc_channel_stack_builder_create();
grpc_channel_stack_builder_set_channel_arguments(
exec_ctx, builder, c->connecting_result.channel_args);
grpc_channel_stack_builder_set_transport(builder,
c->connecting_result.transport);
if (!grpc_channel_init_create_stack(exec_ctx, builder,
GRPC_CLIENT_SUBCHANNEL)) {
grpc_channel_stack_builder_destroy(exec_ctx, builder);
abort(); /* TODO(ctiller): what to do here (previously we just crashed) */
}
grpc_error *error = grpc_channel_stack_builder_finish(
exec_ctx, builder, 0, 1, connection_destroy, NULL, (void **)&con);
if (error != GRPC_ERROR_NONE) {
gpr_log(GPR_ERROR, "error initializing subchannel stack: %s",
grpc_error_string(error));
GRPC_ERROR_UNREF(error);
abort(); /* TODO(ctiller): what to do here? */
}
stk = CHANNEL_STACK_FROM_CONNECTION(con);
memset(&c->connecting_result, 0, sizeof(c->connecting_result));
/* initialize state watcher */
sw_subchannel = gpr_malloc(sizeof(*sw_subchannel));
sw_subchannel->subchannel = c;
sw_subchannel->connectivity_state = GRPC_CHANNEL_READY;
grpc_closure_init(&sw_subchannel->closure, subchannel_on_child_state_changed,
sw_subchannel, grpc_schedule_on_exec_ctx);
if (c->disconnected) {
gpr_free(sw_subchannel);
grpc_channel_stack_destroy(exec_ctx, stk);
gpr_free(con);
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "connecting");
return;
}
/* publish */
/* TODO(ctiller): this full barrier seems to clear up a TSAN failure.
I'd have expected the rel_cas below to be enough, but
seemingly it's not.
Re-evaluate if we really need this. */
gpr_atm_full_barrier();
GPR_ASSERT(gpr_atm_rel_cas(&c->connected_subchannel, 0, (gpr_atm)con));
/* setup subchannel watching connected subchannel for changes; subchannel
ref for connecting is donated to the state watcher */
GRPC_SUBCHANNEL_WEAK_REF(c, "state_watcher");
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "connecting");
grpc_connected_subchannel_notify_on_state_change(
exec_ctx, con, c->pollset_set, &sw_subchannel->connectivity_state,
&sw_subchannel->closure);
/* signal completion */
grpc_connectivity_state_set(exec_ctx, &c->state_tracker, GRPC_CHANNEL_READY,
GRPC_ERROR_NONE, "connected");
}
static void subchannel_connected(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
grpc_subchannel *c = arg;
grpc_channel_args *delete_channel_args = c->connecting_result.channel_args;
GRPC_SUBCHANNEL_WEAK_REF(c, "connected");
gpr_mu_lock(&c->mu);
c->connecting = false;
if (c->connecting_result.transport != NULL) {
publish_transport_locked(exec_ctx, c);
} else if (c->disconnected) {
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "connecting");
} else {
grpc_connectivity_state_set(
exec_ctx, &c->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
grpc_error_set_int(
GRPC_ERROR_CREATE_REFERENCING("Connect Failed", &error, 1),
GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAVAILABLE),
"connect_failed");
const char *errmsg = grpc_error_string(error);
gpr_log(GPR_INFO, "Connect failed: %s", errmsg);
maybe_start_connecting_locked(exec_ctx, c);
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "connecting");
}
gpr_mu_unlock(&c->mu);
GRPC_SUBCHANNEL_WEAK_UNREF(exec_ctx, c, "connected");
grpc_channel_args_destroy(exec_ctx, delete_channel_args);
}
/*
* grpc_subchannel_call implementation
*/
static void subchannel_call_destroy(grpc_exec_ctx *exec_ctx, void *call,
grpc_error *error) {
grpc_subchannel_call *c = call;
GPR_TIMER_BEGIN("grpc_subchannel_call_unref.destroy", 0);
grpc_connected_subchannel *connection = c->connection;
grpc_call_stack_destroy(exec_ctx, SUBCHANNEL_CALL_TO_CALL_STACK(c), NULL, c);
GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, connection, "subchannel_call");
GPR_TIMER_END("grpc_subchannel_call_unref.destroy", 0);
}
void grpc_subchannel_call_ref(
grpc_subchannel_call *c GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
GRPC_CALL_STACK_REF(SUBCHANNEL_CALL_TO_CALL_STACK(c), REF_REASON);
}
void grpc_subchannel_call_unref(grpc_exec_ctx *exec_ctx,
grpc_subchannel_call *c
GRPC_SUBCHANNEL_REF_EXTRA_ARGS) {
GRPC_CALL_STACK_UNREF(exec_ctx, SUBCHANNEL_CALL_TO_CALL_STACK(c), REF_REASON);
}
char *grpc_subchannel_call_get_peer(grpc_exec_ctx *exec_ctx,
grpc_subchannel_call *call) {
grpc_call_stack *call_stack = SUBCHANNEL_CALL_TO_CALL_STACK(call);
grpc_call_element *top_elem = grpc_call_stack_element(call_stack, 0);
return top_elem->filter->get_peer(exec_ctx, top_elem);
}
void grpc_subchannel_call_process_op(grpc_exec_ctx *exec_ctx,
grpc_subchannel_call *call,
grpc_transport_stream_op *op) {
GPR_TIMER_BEGIN("grpc_subchannel_call_process_op", 0);
grpc_call_stack *call_stack = SUBCHANNEL_CALL_TO_CALL_STACK(call);
grpc_call_element *top_elem = grpc_call_stack_element(call_stack, 0);
top_elem->filter->start_transport_stream_op(exec_ctx, top_elem, op);
GPR_TIMER_END("grpc_subchannel_call_process_op", 0);
}
grpc_connected_subchannel *grpc_subchannel_get_connected_subchannel(
grpc_subchannel *c) {
return GET_CONNECTED_SUBCHANNEL(c, acq);
}
grpc_error *grpc_connected_subchannel_create_call(
grpc_exec_ctx *exec_ctx, grpc_connected_subchannel *con,
grpc_polling_entity *pollent, grpc_slice path, gpr_timespec start_time,
gpr_timespec deadline, grpc_subchannel_call **call) {
grpc_channel_stack *chanstk = CHANNEL_STACK_FROM_CONNECTION(con);
*call = gpr_malloc(sizeof(grpc_subchannel_call) + chanstk->call_stack_size);
grpc_call_stack *callstk = SUBCHANNEL_CALL_TO_CALL_STACK(*call);
(*call)->connection = con; // Ref is added below.
grpc_error *error =
grpc_call_stack_init(exec_ctx, chanstk, 1, subchannel_call_destroy, *call,
NULL, NULL, path, start_time, deadline, callstk);
if (error != GRPC_ERROR_NONE) {
const char *error_string = grpc_error_string(error);
gpr_log(GPR_ERROR, "error: %s", error_string);
gpr_free(*call);
return error;
}
GRPC_CONNECTED_SUBCHANNEL_REF(con, "subchannel_call");
grpc_call_stack_set_pollset_or_pollset_set(exec_ctx, callstk, pollent);
return GRPC_ERROR_NONE;
}
grpc_call_stack *grpc_subchannel_call_get_call_stack(
grpc_subchannel_call *subchannel_call) {
return SUBCHANNEL_CALL_TO_CALL_STACK(subchannel_call);
}
static void grpc_uri_to_sockaddr(const char *uri_str,
grpc_resolved_address *addr) {
grpc_uri *uri = grpc_uri_parse(uri_str, 0 /* suppress_errors */);
GPR_ASSERT(uri != NULL);
if (strcmp(uri->scheme, "ipv4") == 0) {
GPR_ASSERT(parse_ipv4(uri, addr));
} else if (strcmp(uri->scheme, "ipv6") == 0) {
GPR_ASSERT(parse_ipv6(uri, addr));
} else {
GPR_ASSERT(parse_unix(uri, addr));
}
grpc_uri_destroy(uri);
}
void grpc_get_subchannel_address_arg(const grpc_channel_args *args,
grpc_resolved_address *addr) {
const char *addr_uri_str = grpc_get_subchannel_address_uri_arg(args);
memset(addr, 0, sizeof(*addr));
if (*addr_uri_str != '\0') {
grpc_uri_to_sockaddr(addr_uri_str, addr);
}
}
const char *grpc_get_subchannel_address_uri_arg(const grpc_channel_args *args) {
const grpc_arg *addr_arg =
grpc_channel_args_find(args, GRPC_ARG_SUBCHANNEL_ADDRESS);
GPR_ASSERT(addr_arg != NULL); // Should have been set by LB policy.
GPR_ASSERT(addr_arg->type == GRPC_ARG_STRING);
return addr_arg->value.string;
}
grpc_arg grpc_create_subchannel_address_arg(const grpc_resolved_address *addr) {
grpc_arg new_arg;
new_arg.key = GRPC_ARG_SUBCHANNEL_ADDRESS;
new_arg.type = GRPC_ARG_STRING;
new_arg.value.string =
addr->len > 0 ? grpc_sockaddr_to_uri(addr) : gpr_strdup("");
return new_arg;
}