1 /* 2 * 3 * Copyright 2015 gRPC authors. 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 * 17 */ 18 19 #ifndef GRPC_CORE_LIB_IOMGR_POLLSET_H 20 #define GRPC_CORE_LIB_IOMGR_POLLSET_H 21 22 #include <grpc/support/port_platform.h> 23 24 #include <grpc/support/sync.h> 25 #include <grpc/support/time.h> 26 27 #include "src/core/lib/iomgr/exec_ctx.h" 28 29 extern grpc_core::DebugOnlyTraceFlag grpc_trace_fd_refcount; 30 31 /* A grpc_pollset is a set of file descriptors that a higher level item is 32 interested in. For example: 33 - a server will typically keep a pollset containing all connected channels, 34 so that it can find new calls to service 35 - a completion queue might keep a pollset with an entry for each transport 36 that is servicing a call that it's tracking */ 37 38 typedef struct grpc_pollset grpc_pollset; 39 typedef struct grpc_pollset_worker grpc_pollset_worker; 40 41 typedef struct grpc_pollset_vtable { 42 void (*global_init)(void); 43 void (*global_shutdown)(void); 44 void (*init)(grpc_pollset* pollset, gpr_mu** mu); 45 void (*shutdown)(grpc_pollset* pollset, grpc_closure* closure); 46 void (*destroy)(grpc_pollset* pollset); 47 grpc_error* (*work)(grpc_pollset* pollset, grpc_pollset_worker** worker, 48 grpc_millis deadline); 49 grpc_error* (*kick)(grpc_pollset* pollset, 50 grpc_pollset_worker* specific_worker); 51 size_t (*pollset_size)(void); 52 } grpc_pollset_vtable; 53 54 void grpc_set_pollset_vtable(grpc_pollset_vtable* vtable); 55 56 void grpc_pollset_global_init(void); 57 void grpc_pollset_global_shutdown(void); 58 59 size_t grpc_pollset_size(void); 60 /* Initialize a pollset: assumes *pollset contains all zeros */ 61 void grpc_pollset_init(grpc_pollset* pollset, gpr_mu** mu); 62 /* Begin shutting down the pollset, and call closure when done. 63 * pollset's mutex must be held */ 64 void grpc_pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure); 65 void grpc_pollset_destroy(grpc_pollset* pollset); 66 67 /* Do some work on a pollset. 68 May involve invoking asynchronous callbacks, or actually polling file 69 descriptors. 70 Requires pollset's mutex locked. 71 May unlock its mutex during its execution. 72 73 worker is a (platform-specific) handle that can be used to wake up 74 from grpc_pollset_work before any events are received and before the timeout 75 has expired. It is both initialized and destroyed by grpc_pollset_work. 76 Initialization of worker is guaranteed to occur BEFORE the 77 pollset's mutex is released for the first time by grpc_pollset_work 78 and it is guaranteed that it will not be released by grpc_pollset_work 79 AFTER worker has been destroyed. 80 81 It's legal for worker to be NULL: in that case, this specific thread can not 82 be directly woken with a kick, but maybe be indirectly (with a kick against 83 the pollset as a whole). 84 85 Tries not to block past deadline. 86 May call grpc_closure_list_run on grpc_closure_list, without holding the 87 pollset 88 lock */ 89 grpc_error* grpc_pollset_work(grpc_pollset* pollset, 90 grpc_pollset_worker** worker, 91 grpc_millis deadline) GRPC_MUST_USE_RESULT; 92 93 /* Break one polling thread out of polling work for this pollset. 94 If specific_worker is non-NULL, then kick that worker. */ 95 grpc_error* grpc_pollset_kick(grpc_pollset* pollset, 96 grpc_pollset_worker* specific_worker) 97 GRPC_MUST_USE_RESULT; 98 99 #endif /* GRPC_CORE_LIB_IOMGR_POLLSET_H */ 100
