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 #include <grpc/support/port_platform.h> 20 21 #include "src/core/ext/transport/chttp2/transport/chttp2_transport.h" 22 #include "src/core/ext/transport/chttp2/transport/internal.h" 23 24 #include <grpc/support/log.h> 25 26 static const char* stream_list_id_string(grpc_chttp2_stream_list_id id) { 27 switch (id) { 28 case GRPC_CHTTP2_LIST_WRITABLE: 29 return "writable"; 30 case GRPC_CHTTP2_LIST_WRITING: 31 return "writing"; 32 case GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT: 33 return "stalled_by_transport"; 34 case GRPC_CHTTP2_LIST_STALLED_BY_STREAM: 35 return "stalled_by_stream"; 36 case GRPC_CHTTP2_LIST_WAITING_FOR_CONCURRENCY: 37 return "waiting_for_concurrency"; 38 case STREAM_LIST_COUNT: 39 GPR_UNREACHABLE_CODE(return "unknown"); 40 } 41 GPR_UNREACHABLE_CODE(return "unknown"); 42 } 43 44 grpc_core::TraceFlag grpc_trace_http2_stream_state(false, "http2_stream_state"); 45 46 /* core list management */ 47 48 static bool stream_list_empty(grpc_chttp2_transport* t, 49 grpc_chttp2_stream_list_id id) { 50 return t->lists[id].head == nullptr; 51 } 52 53 static bool stream_list_pop(grpc_chttp2_transport* t, 54 grpc_chttp2_stream** stream, 55 grpc_chttp2_stream_list_id id) { 56 grpc_chttp2_stream* s = t->lists[id].head; 57 if (s) { 58 grpc_chttp2_stream* new_head = s->links[id].next; 59 GPR_ASSERT(s->included[id]); 60 if (new_head) { 61 t->lists[id].head = new_head; 62 new_head->links[id].prev = nullptr; 63 } else { 64 t->lists[id].head = nullptr; 65 t->lists[id].tail = nullptr; 66 } 67 s->included[id] = 0; 68 } 69 *stream = s; 70 if (s && grpc_trace_http2_stream_state.enabled()) { 71 gpr_log(GPR_INFO, "%p[%d][%s]: pop from %s", t, s->id, 72 t->is_client ? "cli" : "svr", stream_list_id_string(id)); 73 } 74 return s != nullptr; 75 } 76 77 static void stream_list_remove(grpc_chttp2_transport* t, grpc_chttp2_stream* s, 78 grpc_chttp2_stream_list_id id) { 79 GPR_ASSERT(s->included[id]); 80 s->included[id] = 0; 81 if (s->links[id].prev) { 82 s->links[id].prev->links[id].next = s->links[id].next; 83 } else { 84 GPR_ASSERT(t->lists[id].head == s); 85 t->lists[id].head = s->links[id].next; 86 } 87 if (s->links[id].next) { 88 s->links[id].next->links[id].prev = s->links[id].prev; 89 } else { 90 t->lists[id].tail = s->links[id].prev; 91 } 92 if (grpc_trace_http2_stream_state.enabled()) { 93 gpr_log(GPR_INFO, "%p[%d][%s]: remove from %s", t, s->id, 94 t->is_client ? "cli" : "svr", stream_list_id_string(id)); 95 } 96 } 97 98 static bool stream_list_maybe_remove(grpc_chttp2_transport* t, 99 grpc_chttp2_stream* s, 100 grpc_chttp2_stream_list_id id) { 101 if (s->included[id]) { 102 stream_list_remove(t, s, id); 103 return true; 104 } else { 105 return false; 106 } 107 } 108 109 static void stream_list_add_tail(grpc_chttp2_transport* t, 110 grpc_chttp2_stream* s, 111 grpc_chttp2_stream_list_id id) { 112 grpc_chttp2_stream* old_tail; 113 GPR_ASSERT(!s->included[id]); 114 old_tail = t->lists[id].tail; 115 s->links[id].next = nullptr; 116 s->links[id].prev = old_tail; 117 if (old_tail) { 118 old_tail->links[id].next = s; 119 } else { 120 t->lists[id].head = s; 121 } 122 t->lists[id].tail = s; 123 s->included[id] = 1; 124 if (grpc_trace_http2_stream_state.enabled()) { 125 gpr_log(GPR_INFO, "%p[%d][%s]: add to %s", t, s->id, 126 t->is_client ? "cli" : "svr", stream_list_id_string(id)); 127 } 128 } 129 130 static bool stream_list_add(grpc_chttp2_transport* t, grpc_chttp2_stream* s, 131 grpc_chttp2_stream_list_id id) { 132 if (s->included[id]) { 133 return false; 134 } 135 stream_list_add_tail(t, s, id); 136 return true; 137 } 138 139 /* wrappers for specializations */ 140 141 bool grpc_chttp2_list_add_writable_stream(grpc_chttp2_transport* t, 142 grpc_chttp2_stream* s) { 143 GPR_ASSERT(s->id != 0); 144 return stream_list_add(t, s, GRPC_CHTTP2_LIST_WRITABLE); 145 } 146 147 bool grpc_chttp2_list_pop_writable_stream(grpc_chttp2_transport* t, 148 grpc_chttp2_stream** s) { 149 return stream_list_pop(t, s, GRPC_CHTTP2_LIST_WRITABLE); 150 } 151 152 bool grpc_chttp2_list_remove_writable_stream(grpc_chttp2_transport* t, 153 grpc_chttp2_stream* s) { 154 return stream_list_maybe_remove(t, s, GRPC_CHTTP2_LIST_WRITABLE); 155 } 156 157 bool grpc_chttp2_list_add_writing_stream(grpc_chttp2_transport* t, 158 grpc_chttp2_stream* s) { 159 return stream_list_add(t, s, GRPC_CHTTP2_LIST_WRITING); 160 } 161 162 bool grpc_chttp2_list_have_writing_streams(grpc_chttp2_transport* t) { 163 return !stream_list_empty(t, GRPC_CHTTP2_LIST_WRITING); 164 } 165 166 bool grpc_chttp2_list_pop_writing_stream(grpc_chttp2_transport* t, 167 grpc_chttp2_stream** s) { 168 return stream_list_pop(t, s, GRPC_CHTTP2_LIST_WRITING); 169 } 170 171 void grpc_chttp2_list_add_waiting_for_concurrency(grpc_chttp2_transport* t, 172 grpc_chttp2_stream* s) { 173 stream_list_add(t, s, GRPC_CHTTP2_LIST_WAITING_FOR_CONCURRENCY); 174 } 175 176 bool grpc_chttp2_list_pop_waiting_for_concurrency(grpc_chttp2_transport* t, 177 grpc_chttp2_stream** s) { 178 return stream_list_pop(t, s, GRPC_CHTTP2_LIST_WAITING_FOR_CONCURRENCY); 179 } 180 181 void grpc_chttp2_list_remove_waiting_for_concurrency(grpc_chttp2_transport* t, 182 grpc_chttp2_stream* s) { 183 stream_list_maybe_remove(t, s, GRPC_CHTTP2_LIST_WAITING_FOR_CONCURRENCY); 184 } 185 186 void grpc_chttp2_list_add_stalled_by_transport(grpc_chttp2_transport* t, 187 grpc_chttp2_stream* s) { 188 GPR_ASSERT(t->flow_control->flow_control_enabled()); 189 stream_list_add(t, s, GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT); 190 } 191 192 bool grpc_chttp2_list_pop_stalled_by_transport(grpc_chttp2_transport* t, 193 grpc_chttp2_stream** s) { 194 return stream_list_pop(t, s, GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT); 195 } 196 197 void grpc_chttp2_list_remove_stalled_by_transport(grpc_chttp2_transport* t, 198 grpc_chttp2_stream* s) { 199 stream_list_maybe_remove(t, s, GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT); 200 } 201 202 void grpc_chttp2_list_add_stalled_by_stream(grpc_chttp2_transport* t, 203 grpc_chttp2_stream* s) { 204 GPR_ASSERT(t->flow_control->flow_control_enabled()); 205 stream_list_add(t, s, GRPC_CHTTP2_LIST_STALLED_BY_STREAM); 206 } 207 208 bool grpc_chttp2_list_pop_stalled_by_stream(grpc_chttp2_transport* t, 209 grpc_chttp2_stream** s) { 210 return stream_list_pop(t, s, GRPC_CHTTP2_LIST_STALLED_BY_STREAM); 211 } 212 213 bool grpc_chttp2_list_remove_stalled_by_stream(grpc_chttp2_transport* t, 214 grpc_chttp2_stream* s) { 215 return stream_list_maybe_remove(t, s, GRPC_CHTTP2_LIST_STALLED_BY_STREAM); 216 } 217
