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/*
*
* 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/client_config/lb_policy.h"
#define WEAK_REF_BITS 16
void grpc_lb_policy_init(grpc_lb_policy *policy,
const grpc_lb_policy_vtable *vtable) {
policy->vtable = vtable;
gpr_atm_no_barrier_store(&policy->ref_pair, 1 << WEAK_REF_BITS);
grpc_pollset_set_init(&policy->interested_parties);
}
#ifdef GRPC_LB_POLICY_REFCOUNT_DEBUG
#define REF_FUNC_EXTRA_ARGS , const char *file, int line, const char *reason
#define REF_MUTATE_EXTRA_ARGS REF_FUNC_EXTRA_ARGS, const char *purpose
#define REF_FUNC_PASS_ARGS(new_reason) , file, line, new_reason
#define REF_MUTATE_PASS_ARGS(purpose) , file, line, reason, purpose
#else
#define REF_FUNC_EXTRA_ARGS
#define REF_MUTATE_EXTRA_ARGS
#define REF_FUNC_PASS_ARGS(new_reason)
#define REF_MUTATE_PASS_ARGS(x)
#endif
static gpr_atm ref_mutate(grpc_lb_policy *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_LB_POLICY_REFCOUNT_DEBUG
gpr_log(file, line, GPR_LOG_SEVERITY_DEBUG,
"LB_POLICY: %p % 12s 0x%08x -> 0x%08x [%s]", c, purpose, old_val,
old_val + delta, reason);
#endif
return old_val;
}
void grpc_lb_policy_ref(grpc_lb_policy *policy REF_FUNC_EXTRA_ARGS) {
ref_mutate(policy, 1 << WEAK_REF_BITS, 0 REF_MUTATE_PASS_ARGS("STRONG_REF"));
}
void grpc_lb_policy_unref(grpc_exec_ctx *exec_ctx,
grpc_lb_policy *policy REF_FUNC_EXTRA_ARGS) {
gpr_atm old_val =
ref_mutate(policy, (gpr_atm)1 - (gpr_atm)(1 << WEAK_REF_BITS),
1 REF_MUTATE_PASS_ARGS("STRONG_UNREF"));
gpr_atm mask = ~(gpr_atm)((1 << WEAK_REF_BITS) - 1);
gpr_atm check = 1 << WEAK_REF_BITS;
if ((old_val & mask) == check) {
policy->vtable->shutdown(exec_ctx, policy);
}
grpc_lb_policy_weak_unref(exec_ctx,
policy REF_FUNC_PASS_ARGS("strong-unref"));
}
void grpc_lb_policy_weak_ref(grpc_lb_policy *policy REF_FUNC_EXTRA_ARGS) {
ref_mutate(policy, 1, 0 REF_MUTATE_PASS_ARGS("WEAK_REF"));
}
void grpc_lb_policy_weak_unref(grpc_exec_ctx *exec_ctx,
grpc_lb_policy *policy REF_FUNC_EXTRA_ARGS) {
gpr_atm old_val =
ref_mutate(policy, -(gpr_atm)1, 1 REF_MUTATE_PASS_ARGS("WEAK_UNREF"));
if (old_val == 1) {
grpc_pollset_set_destroy(&policy->interested_parties);
policy->vtable->destroy(exec_ctx, policy);
}
}
int grpc_lb_policy_pick(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
grpc_pollset *pollset,
grpc_metadata_batch *initial_metadata,
grpc_connected_subchannel **target,
grpc_closure *on_complete) {
return policy->vtable->pick(exec_ctx, policy, pollset, initial_metadata,
target, on_complete);
}
void grpc_lb_policy_cancel_pick(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
grpc_connected_subchannel **target) {
policy->vtable->cancel_pick(exec_ctx, policy, target);
}
void grpc_lb_policy_exit_idle(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy) {
policy->vtable->exit_idle(exec_ctx, policy);
}
void grpc_lb_policy_notify_on_state_change(grpc_exec_ctx *exec_ctx,
grpc_lb_policy *policy,
grpc_connectivity_state *state,
grpc_closure *closure) {
policy->vtable->notify_on_state_change(exec_ctx, policy, state, closure);
}
grpc_connectivity_state grpc_lb_policy_check_connectivity(
grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy) {
return policy->vtable->check_connectivity(exec_ctx, policy);
}
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