| /* |
| * |
| * Copyright 2017 gRPC authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include "src/core/lib/iomgr/port.h" |
| |
| #ifdef GRPC_POSIX_FORK |
| |
| #include <string.h> |
| |
| #include <grpc/fork.h> |
| #include <grpc/grpc.h> |
| #include <grpc/support/log.h> |
| |
| #include "src/core/lib/gpr/env.h" |
| #include "src/core/lib/gprpp/fork.h" |
| #include "src/core/lib/gprpp/thd.h" |
| #include "src/core/lib/iomgr/ev_posix.h" |
| #include "src/core/lib/iomgr/executor.h" |
| #include "src/core/lib/iomgr/timer_manager.h" |
| #include "src/core/lib/iomgr/wakeup_fd_posix.h" |
| |
| /* |
| * NOTE: FORKING IS NOT GENERALLY SUPPORTED, THIS IS ONLY INTENDED TO WORK |
| * AROUND VERY SPECIFIC USE CASES. |
| */ |
| |
| namespace { |
| bool skipped_handler = true; |
| bool registered_handlers = false; |
| } // namespace |
| |
| void grpc_prefork() { |
| grpc_core::ExecCtx exec_ctx; |
| skipped_handler = true; |
| if (!grpc_is_initialized()) { |
| return; |
| } |
| if (!grpc_core::Fork::Enabled()) { |
| gpr_log(GPR_ERROR, |
| "Fork support not enabled; try running with the " |
| "environment variable GRPC_ENABLE_FORK_SUPPORT=1"); |
| return; |
| } |
| if (strcmp(grpc_get_poll_strategy_name(), "epoll1") != 0 && |
| strcmp(grpc_get_poll_strategy_name(), "poll") != 0) { |
| gpr_log(GPR_INFO, |
| "Fork support is only compatible with the epoll1 and poll polling " |
| "strategies"); |
| } |
| if (!grpc_core::Fork::BlockExecCtx()) { |
| gpr_log(GPR_INFO, |
| "Other threads are currently calling into gRPC, skipping fork() " |
| "handlers"); |
| return; |
| } |
| grpc_timer_manager_set_threading(false); |
| grpc_executor_set_threading(false); |
| grpc_core::ExecCtx::Get()->Flush(); |
| grpc_core::Fork::AwaitThreads(); |
| skipped_handler = false; |
| } |
| |
| void grpc_postfork_parent() { |
| if (!skipped_handler) { |
| grpc_core::Fork::AllowExecCtx(); |
| grpc_core::ExecCtx exec_ctx; |
| grpc_timer_manager_set_threading(true); |
| grpc_executor_set_threading(true); |
| } |
| } |
| |
| void grpc_postfork_child() { |
| if (!skipped_handler) { |
| grpc_core::Fork::AllowExecCtx(); |
| grpc_core::ExecCtx exec_ctx; |
| grpc_core::Fork::child_postfork_func reset_polling_engine = |
| grpc_core::Fork::GetResetChildPollingEngineFunc(); |
| if (reset_polling_engine != nullptr) { |
| reset_polling_engine(); |
| } |
| grpc_timer_manager_set_threading(true); |
| grpc_executor_set_threading(true); |
| } |
| } |
| |
| void grpc_fork_handlers_auto_register() { |
| if (grpc_core::Fork::Enabled() & !registered_handlers) { |
| #ifdef GRPC_POSIX_FORK_ALLOW_PTHREAD_ATFORK |
| pthread_atfork(grpc_prefork, grpc_postfork_parent, grpc_postfork_child); |
| registered_handlers = true; |
| #endif // GRPC_POSIX_FORK_ALLOW_PTHREAD_ATFORK |
| } |
| } |
| |
| #endif // GRPC_POSIX_FORK |