diff options
Diffstat (limited to 'src/core/ext/client_channel/lb_policy.c')
| -rw-r--r-- | src/core/ext/client_channel/lb_policy.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/src/core/ext/client_channel/lb_policy.c b/src/core/ext/client_channel/lb_policy.c new file mode 100644 index 0000000000..45ee72e2f0 --- /dev/null +++ b/src/core/ext/client_channel/lb_policy.c @@ -0,0 +1,146 @@ +/* + * + * 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/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); + policy->interested_parties = grpc_pollset_set_create(); +} + +#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: 0x%" PRIxPTR " %12s 0x%" PRIxPTR " -> 0x%" PRIxPTR + " [%s]", + (intptr_t)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, + const grpc_lb_policy_pick_args *pick_args, + grpc_connected_subchannel **target, void **user_data, + grpc_closure *on_complete) { + return policy->vtable->pick(exec_ctx, policy, pick_args, target, user_data, + on_complete); +} + +void grpc_lb_policy_cancel_pick(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy, + grpc_connected_subchannel **target, + grpc_error *error) { + policy->vtable->cancel_pick(exec_ctx, policy, target, error); +} + +void grpc_lb_policy_cancel_picks(grpc_exec_ctx *exec_ctx, + grpc_lb_policy *policy, + uint32_t initial_metadata_flags_mask, + uint32_t initial_metadata_flags_eq, + grpc_error *error) { + policy->vtable->cancel_picks(exec_ctx, policy, initial_metadata_flags_mask, + initial_metadata_flags_eq, error); +} + +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_ping_one(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy, + grpc_closure *closure) { + policy->vtable->ping_one(exec_ctx, policy, closure); +} + +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, + grpc_error **connectivity_error) { + return policy->vtable->check_connectivity(exec_ctx, policy, + connectivity_error); +} |