Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1 | /* |
| 2 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 3 | * Copyright 2017 gRPC authors. |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 4 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 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 |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 8 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 10 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 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. |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 16 | * |
| 17 | */ |
| 18 | |
| 19 | #include "src/core/lib/iomgr/port.h" |
| 20 | |
| 21 | /* This polling engine is only relevant on linux kernels supporting epoll() */ |
| 22 | #ifdef GRPC_LINUX_EPOLL |
| 23 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 24 | #include "src/core/lib/iomgr/ev_epoll1_linux.h" |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 25 | |
| 26 | #include <assert.h> |
| 27 | #include <errno.h> |
| 28 | #include <poll.h> |
| 29 | #include <pthread.h> |
| 30 | #include <string.h> |
| 31 | #include <sys/epoll.h> |
| 32 | #include <sys/socket.h> |
| 33 | #include <unistd.h> |
| 34 | |
| 35 | #include <grpc/support/alloc.h> |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 36 | #include <grpc/support/cpu.h> |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 37 | #include <grpc/support/log.h> |
| 38 | #include <grpc/support/string_util.h> |
| 39 | #include <grpc/support/tls.h> |
| 40 | #include <grpc/support/useful.h> |
| 41 | |
| 42 | #include "src/core/lib/iomgr/ev_posix.h" |
| 43 | #include "src/core/lib/iomgr/iomgr_internal.h" |
| 44 | #include "src/core/lib/iomgr/lockfree_event.h" |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 45 | #include "src/core/lib/iomgr/wakeup_fd_posix.h" |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 46 | #include "src/core/lib/profiling/timers.h" |
| 47 | #include "src/core/lib/support/block_annotate.h" |
Craig Tiller | b89bac0 | 2017-05-26 15:20:32 +0000 | [diff] [blame] | 48 | #include "src/core/lib/support/string.h" |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 49 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 50 | static grpc_wakeup_fd global_wakeup_fd; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 51 | |
| 52 | /******************************************************************************* |
| 53 | * Singleton epoll set related fields |
| 54 | */ |
| 55 | |
| 56 | #define MAX_EPOLL_EVENTS 100 |
Sree Kuchibhotla | 1961452 | 2017-08-25 17:10:10 -0700 | [diff] [blame] | 57 | #define MAX_EPOLL_EVENTS_HANDLED_PER_ITERATION 1 |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 58 | |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 59 | /* NOTE ON SYNCHRONIZATION: |
| 60 | - Fields in this struct are only modified by the designated poller. Hence |
| 61 | there is no need for any locks to protect the struct. |
| 62 | |
| 63 | - num_events and cursor fields have to be of atomic type to provide memory |
| 64 | visibility guarantees only. i.e In case of multiple pollers, the designated |
| 65 | polling thread keeps changing; the thread that wrote these values may be |
| 66 | different from the thread reading the values */ |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 67 | typedef struct epoll_set { |
| 68 | int epfd; |
| 69 | |
| 70 | /* The epoll_events after the last call to epoll_wait() */ |
| 71 | struct epoll_event events[MAX_EPOLL_EVENTS]; |
| 72 | |
| 73 | /* The number of epoll_events after the last call to epoll_wait() */ |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 74 | gpr_atm num_events; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 75 | |
| 76 | /* Index of the first event in epoll_events that has to be processed. This |
| 77 | * field is only valid if num_events > 0 */ |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 78 | gpr_atm cursor; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 79 | } epoll_set; |
| 80 | |
| 81 | /* The global singleton epoll set */ |
| 82 | static epoll_set g_epoll_set; |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 83 | static gpr_atm g_cs = 0; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 84 | |
| 85 | /* Must be called *only* once */ |
| 86 | static bool epoll_set_init() { |
| 87 | g_epoll_set.epfd = epoll_create1(EPOLL_CLOEXEC); |
| 88 | if (g_epoll_set.epfd < 0) { |
| 89 | gpr_log(GPR_ERROR, "epoll unavailable"); |
| 90 | return false; |
| 91 | } |
| 92 | |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 93 | gpr_log(GPR_INFO, "grpc epoll fd: %d", g_epoll_set.epfd); |
| 94 | gpr_atm_no_barrier_store(&g_epoll_set.num_events, 0); |
| 95 | gpr_atm_no_barrier_store(&g_epoll_set.cursor, 0); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 96 | return true; |
| 97 | } |
| 98 | |
| 99 | /* epoll_set_init() MUST be called before calling this. */ |
| 100 | static void epoll_set_shutdown() { |
| 101 | if (g_epoll_set.epfd >= 0) { |
| 102 | close(g_epoll_set.epfd); |
| 103 | g_epoll_set.epfd = -1; |
| 104 | } |
| 105 | } |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 106 | |
| 107 | /******************************************************************************* |
| 108 | * Fd Declarations |
| 109 | */ |
| 110 | |
| 111 | struct grpc_fd { |
| 112 | int fd; |
| 113 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 114 | gpr_atm read_closure; |
| 115 | gpr_atm write_closure; |
| 116 | |
| 117 | struct grpc_fd *freelist_next; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 118 | |
| 119 | /* The pollset that last noticed that the fd is readable. The actual type |
| 120 | * stored in this is (grpc_pollset *) */ |
| 121 | gpr_atm read_notifier_pollset; |
| 122 | |
| 123 | grpc_iomgr_object iomgr_object; |
| 124 | }; |
| 125 | |
| 126 | static void fd_global_init(void); |
| 127 | static void fd_global_shutdown(void); |
| 128 | |
| 129 | /******************************************************************************* |
| 130 | * Pollset Declarations |
| 131 | */ |
| 132 | |
Craig Tiller | 43bf259 | 2017-04-28 23:21:01 +0000 | [diff] [blame] | 133 | typedef enum { UNKICKED, KICKED, DESIGNATED_POLLER } kick_state; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 134 | |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 135 | static const char *kick_state_string(kick_state st) { |
| 136 | switch (st) { |
| 137 | case UNKICKED: |
| 138 | return "UNKICKED"; |
| 139 | case KICKED: |
| 140 | return "KICKED"; |
| 141 | case DESIGNATED_POLLER: |
| 142 | return "DESIGNATED_POLLER"; |
| 143 | } |
| 144 | GPR_UNREACHABLE_CODE(return "UNKNOWN"); |
| 145 | } |
| 146 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 147 | struct grpc_pollset_worker { |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 148 | kick_state kick_state; |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 149 | int kick_state_mutator; // which line of code last changed kick state |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 150 | bool initialized_cv; |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 151 | grpc_pollset_worker *next; |
| 152 | grpc_pollset_worker *prev; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 153 | gpr_cv cv; |
Craig Tiller | 50da5ec | 2017-05-01 13:51:14 -0700 | [diff] [blame] | 154 | grpc_closure_list schedule_on_end_work; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 155 | }; |
| 156 | |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 157 | #define SET_KICK_STATE(worker, state) \ |
| 158 | do { \ |
| 159 | (worker)->kick_state = (state); \ |
| 160 | (worker)->kick_state_mutator = __LINE__; \ |
| 161 | } while (false) |
| 162 | |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 163 | #define MAX_NEIGHBOURHOODS 1024 |
| 164 | |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 165 | typedef struct pollset_neighbourhood { |
| 166 | gpr_mu mu; |
| 167 | grpc_pollset *active_root; |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 168 | char pad[GPR_CACHELINE_SIZE]; |
| 169 | } pollset_neighbourhood; |
| 170 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 171 | struct grpc_pollset { |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 172 | gpr_mu mu; |
| 173 | pollset_neighbourhood *neighbourhood; |
Craig Tiller | e00d733 | 2017-05-01 15:43:51 +0000 | [diff] [blame] | 174 | bool reassigning_neighbourhood; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 175 | grpc_pollset_worker *root_worker; |
| 176 | bool kicked_without_poller; |
Sree Kuchibhotla | 0d8431a | 2017-07-18 16:21:54 -0700 | [diff] [blame] | 177 | |
| 178 | /* Set to true if the pollset is observed to have no workers available to |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 179 | poll */ |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 180 | bool seen_inactive; |
Sree Kuchibhotla | 0d8431a | 2017-07-18 16:21:54 -0700 | [diff] [blame] | 181 | bool shutting_down; /* Is the pollset shutting down ? */ |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 182 | grpc_closure *shutdown_closure; /* Called after after shutdown is complete */ |
Sree Kuchibhotla | 0d8431a | 2017-07-18 16:21:54 -0700 | [diff] [blame] | 183 | |
| 184 | /* Number of workers who are *about-to* attach themselves to the pollset |
| 185 | * worker list */ |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 186 | int begin_refs; |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 187 | |
| 188 | grpc_pollset *next; |
| 189 | grpc_pollset *prev; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 190 | }; |
| 191 | |
| 192 | /******************************************************************************* |
| 193 | * Pollset-set Declarations |
| 194 | */ |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 195 | |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 196 | struct grpc_pollset_set { |
| 197 | char unused; |
| 198 | }; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 199 | |
| 200 | /******************************************************************************* |
| 201 | * Common helpers |
| 202 | */ |
| 203 | |
| 204 | static bool append_error(grpc_error **composite, grpc_error *error, |
| 205 | const char *desc) { |
| 206 | if (error == GRPC_ERROR_NONE) return true; |
| 207 | if (*composite == GRPC_ERROR_NONE) { |
| 208 | *composite = GRPC_ERROR_CREATE_FROM_COPIED_STRING(desc); |
| 209 | } |
| 210 | *composite = grpc_error_add_child(*composite, error); |
| 211 | return false; |
| 212 | } |
| 213 | |
| 214 | /******************************************************************************* |
| 215 | * Fd Definitions |
| 216 | */ |
| 217 | |
| 218 | /* We need to keep a freelist not because of any concerns of malloc performance |
| 219 | * but instead so that implementations with multiple threads in (for example) |
| 220 | * epoll_wait deal with the race between pollset removal and incoming poll |
| 221 | * notifications. |
| 222 | * |
| 223 | * The problem is that the poller ultimately holds a reference to this |
| 224 | * object, so it is very difficult to know when is safe to free it, at least |
| 225 | * without some expensive synchronization. |
| 226 | * |
| 227 | * If we keep the object freelisted, in the worst case losing this race just |
| 228 | * becomes a spurious read notification on a reused fd. |
| 229 | */ |
| 230 | |
| 231 | /* The alarm system needs to be able to wakeup 'some poller' sometimes |
| 232 | * (specifically when a new alarm needs to be triggered earlier than the next |
| 233 | * alarm 'epoch'). This wakeup_fd gives us something to alert on when such a |
| 234 | * case occurs. */ |
| 235 | |
| 236 | static grpc_fd *fd_freelist = NULL; |
| 237 | static gpr_mu fd_freelist_mu; |
| 238 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 239 | static void fd_global_init(void) { gpr_mu_init(&fd_freelist_mu); } |
| 240 | |
| 241 | static void fd_global_shutdown(void) { |
| 242 | gpr_mu_lock(&fd_freelist_mu); |
| 243 | gpr_mu_unlock(&fd_freelist_mu); |
| 244 | while (fd_freelist != NULL) { |
| 245 | grpc_fd *fd = fd_freelist; |
| 246 | fd_freelist = fd_freelist->freelist_next; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 247 | gpr_free(fd); |
| 248 | } |
| 249 | gpr_mu_destroy(&fd_freelist_mu); |
| 250 | } |
| 251 | |
| 252 | static grpc_fd *fd_create(int fd, const char *name) { |
| 253 | grpc_fd *new_fd = NULL; |
| 254 | |
| 255 | gpr_mu_lock(&fd_freelist_mu); |
| 256 | if (fd_freelist != NULL) { |
| 257 | new_fd = fd_freelist; |
| 258 | fd_freelist = fd_freelist->freelist_next; |
| 259 | } |
| 260 | gpr_mu_unlock(&fd_freelist_mu); |
| 261 | |
| 262 | if (new_fd == NULL) { |
| 263 | new_fd = gpr_malloc(sizeof(grpc_fd)); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 264 | } |
| 265 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 266 | new_fd->fd = fd; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 267 | grpc_lfev_init(&new_fd->read_closure); |
| 268 | grpc_lfev_init(&new_fd->write_closure); |
| 269 | gpr_atm_no_barrier_store(&new_fd->read_notifier_pollset, (gpr_atm)NULL); |
| 270 | |
| 271 | new_fd->freelist_next = NULL; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 272 | |
| 273 | char *fd_name; |
| 274 | gpr_asprintf(&fd_name, "%s fd=%d", name, fd); |
| 275 | grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name); |
Noah Eisen | 264879f | 2017-06-20 17:14:47 -0700 | [diff] [blame] | 276 | #ifndef NDEBUG |
| 277 | if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) { |
| 278 | gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, new_fd, fd_name); |
| 279 | } |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 280 | #endif |
| 281 | gpr_free(fd_name); |
Craig Tiller | 9ddb315 | 2017-04-27 21:32:56 +0000 | [diff] [blame] | 282 | |
| 283 | struct epoll_event ev = {.events = (uint32_t)(EPOLLIN | EPOLLOUT | EPOLLET), |
| 284 | .data.ptr = new_fd}; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 285 | if (epoll_ctl(g_epoll_set.epfd, EPOLL_CTL_ADD, fd, &ev) != 0) { |
Craig Tiller | 9ddb315 | 2017-04-27 21:32:56 +0000 | [diff] [blame] | 286 | gpr_log(GPR_ERROR, "epoll_ctl failed: %s", strerror(errno)); |
| 287 | } |
| 288 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 289 | return new_fd; |
| 290 | } |
| 291 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 292 | static int fd_wrapped_fd(grpc_fd *fd) { return fd->fd; } |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 293 | |
Sree Kuchibhotla | f264147 | 2017-08-02 23:46:40 -0700 | [diff] [blame] | 294 | /* if 'releasing_fd' is true, it means that we are going to detach the internal |
| 295 | * fd from grpc_fd structure (i.e which means we should not be calling |
| 296 | * shutdown() syscall on that fd) */ |
| 297 | static void fd_shutdown_internal(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 298 | grpc_error *why, bool releasing_fd) { |
Craig Tiller | 9ddb315 | 2017-04-27 21:32:56 +0000 | [diff] [blame] | 299 | if (grpc_lfev_set_shutdown(exec_ctx, &fd->read_closure, |
| 300 | GRPC_ERROR_REF(why))) { |
Sree Kuchibhotla | f264147 | 2017-08-02 23:46:40 -0700 | [diff] [blame] | 301 | if (!releasing_fd) { |
| 302 | shutdown(fd->fd, SHUT_RDWR); |
| 303 | } |
Craig Tiller | 9ddb315 | 2017-04-27 21:32:56 +0000 | [diff] [blame] | 304 | grpc_lfev_set_shutdown(exec_ctx, &fd->write_closure, GRPC_ERROR_REF(why)); |
| 305 | } |
| 306 | GRPC_ERROR_UNREF(why); |
| 307 | } |
| 308 | |
Sree Kuchibhotla | f264147 | 2017-08-02 23:46:40 -0700 | [diff] [blame] | 309 | /* Might be called multiple times */ |
| 310 | static void fd_shutdown(grpc_exec_ctx *exec_ctx, grpc_fd *fd, grpc_error *why) { |
| 311 | fd_shutdown_internal(exec_ctx, fd, why, false); |
| 312 | } |
| 313 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 314 | static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 315 | grpc_closure *on_done, int *release_fd, |
Yuchen Zeng | d40a7ae | 2017-07-12 15:59:56 -0700 | [diff] [blame] | 316 | bool already_closed, const char *reason) { |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 317 | grpc_error *error = GRPC_ERROR_NONE; |
Sree Kuchibhotla | f264147 | 2017-08-02 23:46:40 -0700 | [diff] [blame] | 318 | bool is_release_fd = (release_fd != NULL); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 319 | |
Craig Tiller | 9ddb315 | 2017-04-27 21:32:56 +0000 | [diff] [blame] | 320 | if (!grpc_lfev_is_shutdown(&fd->read_closure)) { |
Sree Kuchibhotla | f264147 | 2017-08-02 23:46:40 -0700 | [diff] [blame] | 321 | fd_shutdown_internal(exec_ctx, fd, |
| 322 | GRPC_ERROR_CREATE_FROM_COPIED_STRING(reason), |
| 323 | is_release_fd); |
Craig Tiller | 9ddb315 | 2017-04-27 21:32:56 +0000 | [diff] [blame] | 324 | } |
| 325 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 326 | /* If release_fd is not NULL, we should be relinquishing control of the file |
| 327 | descriptor fd->fd (but we still own the grpc_fd structure). */ |
Sree Kuchibhotla | f264147 | 2017-08-02 23:46:40 -0700 | [diff] [blame] | 328 | if (is_release_fd) { |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 329 | *release_fd = fd->fd; |
Yuchen Zeng | d40a7ae | 2017-07-12 15:59:56 -0700 | [diff] [blame] | 330 | } else if (!already_closed) { |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 331 | close(fd->fd); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 332 | } |
| 333 | |
ncteisen | 274bbbe | 2017-06-08 14:57:11 -0700 | [diff] [blame] | 334 | GRPC_CLOSURE_SCHED(exec_ctx, on_done, GRPC_ERROR_REF(error)); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 335 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 336 | grpc_iomgr_unregister_object(&fd->iomgr_object); |
| 337 | grpc_lfev_destroy(&fd->read_closure); |
| 338 | grpc_lfev_destroy(&fd->write_closure); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 339 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 340 | gpr_mu_lock(&fd_freelist_mu); |
| 341 | fd->freelist_next = fd_freelist; |
| 342 | fd_freelist = fd; |
| 343 | gpr_mu_unlock(&fd_freelist_mu); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 344 | } |
| 345 | |
| 346 | static grpc_pollset *fd_get_read_notifier_pollset(grpc_exec_ctx *exec_ctx, |
| 347 | grpc_fd *fd) { |
| 348 | gpr_atm notifier = gpr_atm_acq_load(&fd->read_notifier_pollset); |
| 349 | return (grpc_pollset *)notifier; |
| 350 | } |
| 351 | |
| 352 | static bool fd_is_shutdown(grpc_fd *fd) { |
| 353 | return grpc_lfev_is_shutdown(&fd->read_closure); |
| 354 | } |
| 355 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 356 | static void fd_notify_on_read(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 357 | grpc_closure *closure) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 358 | grpc_lfev_notify_on(exec_ctx, &fd->read_closure, closure, "read"); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 359 | } |
| 360 | |
| 361 | static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 362 | grpc_closure *closure) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 363 | grpc_lfev_notify_on(exec_ctx, &fd->write_closure, closure, "write"); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 364 | } |
| 365 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 366 | static void fd_become_readable(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 367 | grpc_pollset *notifier) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 368 | grpc_lfev_set_ready(exec_ctx, &fd->read_closure, "read"); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 369 | /* Use release store to match with acquire load in fd_get_read_notifier */ |
| 370 | gpr_atm_rel_store(&fd->read_notifier_pollset, (gpr_atm)notifier); |
| 371 | } |
| 372 | |
| 373 | static void fd_become_writable(grpc_exec_ctx *exec_ctx, grpc_fd *fd) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 374 | grpc_lfev_set_ready(exec_ctx, &fd->write_closure, "write"); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 375 | } |
| 376 | |
| 377 | /******************************************************************************* |
| 378 | * Pollset Definitions |
| 379 | */ |
| 380 | |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 381 | GPR_TLS_DECL(g_current_thread_pollset); |
| 382 | GPR_TLS_DECL(g_current_thread_worker); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 383 | |
| 384 | /* The designated poller */ |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 385 | static gpr_atm g_active_poller; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 386 | |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 387 | static pollset_neighbourhood *g_neighbourhoods; |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 388 | static size_t g_num_neighbourhoods; |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 389 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 390 | /* Return true if first in list */ |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 391 | static bool worker_insert(grpc_pollset *pollset, grpc_pollset_worker *worker) { |
| 392 | if (pollset->root_worker == NULL) { |
| 393 | pollset->root_worker = worker; |
| 394 | worker->next = worker->prev = worker; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 395 | return true; |
| 396 | } else { |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 397 | worker->next = pollset->root_worker; |
| 398 | worker->prev = worker->next->prev; |
| 399 | worker->next->prev = worker; |
| 400 | worker->prev->next = worker; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 401 | return false; |
| 402 | } |
| 403 | } |
| 404 | |
| 405 | /* Return true if last in list */ |
| 406 | typedef enum { EMPTIED, NEW_ROOT, REMOVED } worker_remove_result; |
| 407 | |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 408 | static worker_remove_result worker_remove(grpc_pollset *pollset, |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 409 | grpc_pollset_worker *worker) { |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 410 | if (worker == pollset->root_worker) { |
| 411 | if (worker == worker->next) { |
| 412 | pollset->root_worker = NULL; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 413 | return EMPTIED; |
| 414 | } else { |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 415 | pollset->root_worker = worker->next; |
| 416 | worker->prev->next = worker->next; |
| 417 | worker->next->prev = worker->prev; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 418 | return NEW_ROOT; |
| 419 | } |
| 420 | } else { |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 421 | worker->prev->next = worker->next; |
| 422 | worker->next->prev = worker->prev; |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 423 | return REMOVED; |
| 424 | } |
| 425 | } |
| 426 | |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 427 | static size_t choose_neighbourhood(void) { |
| 428 | return (size_t)gpr_cpu_current_cpu() % g_num_neighbourhoods; |
| 429 | } |
| 430 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 431 | static grpc_error *pollset_global_init(void) { |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 432 | gpr_tls_init(&g_current_thread_pollset); |
| 433 | gpr_tls_init(&g_current_thread_worker); |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 434 | gpr_atm_no_barrier_store(&g_active_poller, 0); |
Craig Tiller | 375eb25 | 2017-04-27 23:29:12 +0000 | [diff] [blame] | 435 | global_wakeup_fd.read_fd = -1; |
| 436 | grpc_error *err = grpc_wakeup_fd_init(&global_wakeup_fd); |
| 437 | if (err != GRPC_ERROR_NONE) return err; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 438 | struct epoll_event ev = {.events = (uint32_t)(EPOLLIN | EPOLLET), |
| 439 | .data.ptr = &global_wakeup_fd}; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 440 | if (epoll_ctl(g_epoll_set.epfd, EPOLL_CTL_ADD, global_wakeup_fd.read_fd, |
| 441 | &ev) != 0) { |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 442 | return GRPC_OS_ERROR(errno, "epoll_ctl"); |
| 443 | } |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 444 | g_num_neighbourhoods = GPR_CLAMP(gpr_cpu_num_cores(), 1, MAX_NEIGHBOURHOODS); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 445 | g_neighbourhoods = |
| 446 | gpr_zalloc(sizeof(*g_neighbourhoods) * g_num_neighbourhoods); |
| 447 | for (size_t i = 0; i < g_num_neighbourhoods; i++) { |
| 448 | gpr_mu_init(&g_neighbourhoods[i].mu); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 449 | } |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 450 | return GRPC_ERROR_NONE; |
| 451 | } |
| 452 | |
| 453 | static void pollset_global_shutdown(void) { |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 454 | gpr_tls_destroy(&g_current_thread_pollset); |
| 455 | gpr_tls_destroy(&g_current_thread_worker); |
Craig Tiller | 375eb25 | 2017-04-27 23:29:12 +0000 | [diff] [blame] | 456 | if (global_wakeup_fd.read_fd != -1) grpc_wakeup_fd_destroy(&global_wakeup_fd); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 457 | for (size_t i = 0; i < g_num_neighbourhoods; i++) { |
| 458 | gpr_mu_destroy(&g_neighbourhoods[i].mu); |
| 459 | } |
| 460 | gpr_free(g_neighbourhoods); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 461 | } |
| 462 | |
| 463 | static void pollset_init(grpc_pollset *pollset, gpr_mu **mu) { |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 464 | gpr_mu_init(&pollset->mu); |
| 465 | *mu = &pollset->mu; |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 466 | pollset->neighbourhood = &g_neighbourhoods[choose_neighbourhood()]; |
Sree Kuchibhotla | 3088230 | 2017-08-16 13:46:52 -0700 | [diff] [blame] | 467 | pollset->reassigning_neighbourhood = false; |
| 468 | pollset->root_worker = NULL; |
| 469 | pollset->kicked_without_poller = false; |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 470 | pollset->seen_inactive = true; |
Sree Kuchibhotla | 3088230 | 2017-08-16 13:46:52 -0700 | [diff] [blame] | 471 | pollset->shutting_down = false; |
| 472 | pollset->shutdown_closure = NULL; |
| 473 | pollset->begin_refs = 0; |
| 474 | pollset->next = pollset->prev = NULL; |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 475 | } |
| 476 | |
Craig Tiller | c610985 | 2017-05-01 14:26:49 -0700 | [diff] [blame] | 477 | static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) { |
Craig Tiller | e00d733 | 2017-05-01 15:43:51 +0000 | [diff] [blame] | 478 | gpr_mu_lock(&pollset->mu); |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 479 | if (!pollset->seen_inactive) { |
Craig Tiller | e00d733 | 2017-05-01 15:43:51 +0000 | [diff] [blame] | 480 | pollset_neighbourhood *neighbourhood = pollset->neighbourhood; |
| 481 | gpr_mu_unlock(&pollset->mu); |
Craig Tiller | a95bacf | 2017-05-01 12:51:24 -0700 | [diff] [blame] | 482 | retry_lock_neighbourhood: |
Craig Tiller | e00d733 | 2017-05-01 15:43:51 +0000 | [diff] [blame] | 483 | gpr_mu_lock(&neighbourhood->mu); |
| 484 | gpr_mu_lock(&pollset->mu); |
| 485 | if (!pollset->seen_inactive) { |
| 486 | if (pollset->neighbourhood != neighbourhood) { |
| 487 | gpr_mu_unlock(&neighbourhood->mu); |
| 488 | neighbourhood = pollset->neighbourhood; |
| 489 | gpr_mu_unlock(&pollset->mu); |
| 490 | goto retry_lock_neighbourhood; |
| 491 | } |
| 492 | pollset->prev->next = pollset->next; |
| 493 | pollset->next->prev = pollset->prev; |
| 494 | if (pollset == pollset->neighbourhood->active_root) { |
| 495 | pollset->neighbourhood->active_root = |
| 496 | pollset->next == pollset ? NULL : pollset->next; |
| 497 | } |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 498 | } |
| 499 | gpr_mu_unlock(&pollset->neighbourhood->mu); |
Craig Tiller | 6de0593 | 2017-04-28 09:17:38 -0700 | [diff] [blame] | 500 | } |
Craig Tiller | e00d733 | 2017-05-01 15:43:51 +0000 | [diff] [blame] | 501 | gpr_mu_unlock(&pollset->mu); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 502 | gpr_mu_destroy(&pollset->mu); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 503 | } |
| 504 | |
| 505 | static grpc_error *pollset_kick_all(grpc_pollset *pollset) { |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 506 | GPR_TIMER_BEGIN("pollset_kick_all", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 507 | grpc_error *error = GRPC_ERROR_NONE; |
| 508 | if (pollset->root_worker != NULL) { |
| 509 | grpc_pollset_worker *worker = pollset->root_worker; |
| 510 | do { |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 511 | switch (worker->kick_state) { |
| 512 | case KICKED: |
| 513 | break; |
| 514 | case UNKICKED: |
| 515 | SET_KICK_STATE(worker, KICKED); |
| 516 | if (worker->initialized_cv) { |
| 517 | gpr_cv_signal(&worker->cv); |
| 518 | } |
| 519 | break; |
| 520 | case DESIGNATED_POLLER: |
| 521 | SET_KICK_STATE(worker, KICKED); |
| 522 | append_error(&error, grpc_wakeup_fd_wakeup(&global_wakeup_fd), |
Sree Kuchibhotla | 0d8431a | 2017-07-18 16:21:54 -0700 | [diff] [blame] | 523 | "pollset_kick_all"); |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 524 | break; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 525 | } |
| 526 | |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 527 | worker = worker->next; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 528 | } while (worker != pollset->root_worker); |
| 529 | } |
Sree Kuchibhotla | 0d8431a | 2017-07-18 16:21:54 -0700 | [diff] [blame] | 530 | // TODO: sreek. Check if we need to set 'kicked_without_poller' to true here |
| 531 | // in the else case |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 532 | GPR_TIMER_END("pollset_kick_all", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 533 | return error; |
| 534 | } |
| 535 | |
| 536 | static void pollset_maybe_finish_shutdown(grpc_exec_ctx *exec_ctx, |
| 537 | grpc_pollset *pollset) { |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 538 | if (pollset->shutdown_closure != NULL && pollset->root_worker == NULL && |
| 539 | pollset->begin_refs == 0) { |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 540 | GPR_TIMER_MARK("pollset_finish_shutdown", 0); |
ncteisen | 274bbbe | 2017-06-08 14:57:11 -0700 | [diff] [blame] | 541 | GRPC_CLOSURE_SCHED(exec_ctx, pollset->shutdown_closure, GRPC_ERROR_NONE); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 542 | pollset->shutdown_closure = NULL; |
| 543 | } |
| 544 | } |
| 545 | |
| 546 | static void pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, |
| 547 | grpc_closure *closure) { |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 548 | GPR_TIMER_BEGIN("pollset_shutdown", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 549 | GPR_ASSERT(pollset->shutdown_closure == NULL); |
Craig Tiller | c81512a | 2017-05-26 09:53:58 -0700 | [diff] [blame] | 550 | GPR_ASSERT(!pollset->shutting_down); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 551 | pollset->shutdown_closure = closure; |
Craig Tiller | c81512a | 2017-05-26 09:53:58 -0700 | [diff] [blame] | 552 | pollset->shutting_down = true; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 553 | GRPC_LOG_IF_ERROR("pollset_shutdown", pollset_kick_all(pollset)); |
| 554 | pollset_maybe_finish_shutdown(exec_ctx, pollset); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 555 | GPR_TIMER_END("pollset_shutdown", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 556 | } |
| 557 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 558 | static int poll_deadline_to_millis_timeout(gpr_timespec deadline, |
| 559 | gpr_timespec now) { |
| 560 | gpr_timespec timeout; |
| 561 | if (gpr_time_cmp(deadline, gpr_inf_future(deadline.clock_type)) == 0) { |
| 562 | return -1; |
| 563 | } |
| 564 | |
| 565 | if (gpr_time_cmp(deadline, now) <= 0) { |
| 566 | return 0; |
| 567 | } |
| 568 | |
| 569 | static const gpr_timespec round_up = { |
| 570 | .clock_type = GPR_TIMESPAN, .tv_sec = 0, .tv_nsec = GPR_NS_PER_MS - 1}; |
| 571 | timeout = gpr_time_sub(deadline, now); |
| 572 | int millis = gpr_time_to_millis(gpr_time_add(timeout, round_up)); |
| 573 | return millis >= 1 ? millis : 1; |
| 574 | } |
| 575 | |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 576 | /* Process the epoll events found by do_epoll_wait() function. |
| 577 | - g_epoll_set.cursor points to the index of the first event to be processed |
| 578 | - This function then processes up-to MAX_EPOLL_EVENTS_PER_ITERATION and |
| 579 | updates the g_epoll_set.cursor |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 580 | |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 581 | NOTE ON SYNCRHONIZATION: Similar to do_epoll_wait(), this function is only |
| 582 | called by g_active_poller thread. So there is no need for synchronization |
| 583 | when accessing fields in g_epoll_set */ |
| 584 | static grpc_error *process_epoll_events(grpc_exec_ctx *exec_ctx, |
| 585 | grpc_pollset *pollset) { |
| 586 | static const char *err_desc = "process_events"; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 587 | grpc_error *error = GRPC_ERROR_NONE; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 588 | |
Sree Kuchibhotla | 3d609f1 | 2017-08-25 10:00:18 -0700 | [diff] [blame] | 589 | GPR_TIMER_BEGIN("process_epoll_events", 0); |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 590 | long num_events = gpr_atm_acq_load(&g_epoll_set.num_events); |
| 591 | long cursor = gpr_atm_acq_load(&g_epoll_set.cursor); |
| 592 | for (int idx = 0; |
| 593 | (idx < MAX_EPOLL_EVENTS_HANDLED_PER_ITERATION) && cursor != num_events; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 594 | idx++) { |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 595 | long c = cursor++; |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 596 | struct epoll_event *ev = &g_epoll_set.events[c]; |
| 597 | void *data_ptr = ev->data.ptr; |
| 598 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 599 | if (data_ptr == &global_wakeup_fd) { |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 600 | append_error(&error, grpc_wakeup_fd_consume_wakeup(&global_wakeup_fd), |
| 601 | err_desc); |
| 602 | } else { |
| 603 | grpc_fd *fd = (grpc_fd *)(data_ptr); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 604 | bool cancel = (ev->events & (EPOLLERR | EPOLLHUP)) != 0; |
| 605 | bool read_ev = (ev->events & (EPOLLIN | EPOLLPRI)) != 0; |
| 606 | bool write_ev = (ev->events & EPOLLOUT) != 0; |
| 607 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 608 | if (read_ev || cancel) { |
| 609 | fd_become_readable(exec_ctx, fd, pollset); |
| 610 | } |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 611 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 612 | if (write_ev || cancel) { |
| 613 | fd_become_writable(exec_ctx, fd); |
| 614 | } |
| 615 | } |
| 616 | } |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 617 | gpr_atm_rel_store(&g_epoll_set.cursor, cursor); |
Sree Kuchibhotla | 3d609f1 | 2017-08-25 10:00:18 -0700 | [diff] [blame] | 618 | GPR_TIMER_END("process_epoll_events", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 619 | return error; |
| 620 | } |
| 621 | |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 622 | /* Do epoll_wait and store the events in g_epoll_set.events field. This does not |
| 623 | "process" any of the events yet; that is done in process_epoll_events(). |
| 624 | *See process_epoll_events() function for more details. |
| 625 | |
| 626 | NOTE ON SYNCHRONIZATION: At any point of time, only the g_active_poller |
| 627 | (i.e the designated poller thread) will be calling this function. So there is |
| 628 | no need for any synchronization when accesing fields in g_epoll_set */ |
| 629 | static grpc_error *do_epoll_wait(grpc_exec_ctx *exec_ctx, grpc_pollset *ps, |
| 630 | gpr_timespec now, gpr_timespec deadline) { |
Sree Kuchibhotla | 3d609f1 | 2017-08-25 10:00:18 -0700 | [diff] [blame] | 631 | GPR_TIMER_BEGIN("do_epoll_wait", 0); |
| 632 | |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 633 | int r; |
| 634 | int timeout = poll_deadline_to_millis_timeout(deadline, now); |
| 635 | if (timeout != 0) { |
| 636 | GRPC_SCHEDULING_START_BLOCKING_REGION; |
| 637 | } |
| 638 | do { |
| 639 | r = epoll_wait(g_epoll_set.epfd, g_epoll_set.events, MAX_EPOLL_EVENTS, |
| 640 | timeout); |
| 641 | } while (r < 0 && errno == EINTR); |
| 642 | if (timeout != 0) { |
| 643 | GRPC_SCHEDULING_END_BLOCKING_REGION; |
| 644 | } |
| 645 | |
| 646 | if (r < 0) return GRPC_OS_ERROR(errno, "epoll_wait"); |
| 647 | |
| 648 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 649 | gpr_log(GPR_DEBUG, "ps: %p poll got %d events", ps, r); |
| 650 | } |
| 651 | |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 652 | gpr_atm_rel_store(&g_epoll_set.num_events, r); |
| 653 | gpr_atm_rel_store(&g_epoll_set.cursor, 0); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 654 | |
Sree Kuchibhotla | 3d609f1 | 2017-08-25 10:00:18 -0700 | [diff] [blame] | 655 | GPR_TIMER_END("do_epoll_wait", 0); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 656 | return GRPC_ERROR_NONE; |
| 657 | } |
| 658 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 659 | static bool begin_worker(grpc_pollset *pollset, grpc_pollset_worker *worker, |
| 660 | grpc_pollset_worker **worker_hdl, gpr_timespec *now, |
| 661 | gpr_timespec deadline) { |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 662 | GPR_TIMER_BEGIN("begin_worker", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 663 | if (worker_hdl != NULL) *worker_hdl = worker; |
| 664 | worker->initialized_cv = false; |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 665 | SET_KICK_STATE(worker, UNKICKED); |
Craig Tiller | 50da5ec | 2017-05-01 13:51:14 -0700 | [diff] [blame] | 666 | worker->schedule_on_end_work = (grpc_closure_list)GRPC_CLOSURE_LIST_INIT; |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 667 | pollset->begin_refs++; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 668 | |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 669 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 670 | gpr_log(GPR_ERROR, "PS:%p BEGIN_STARTS:%p", pollset, worker); |
| 671 | } |
| 672 | |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 673 | if (pollset->seen_inactive) { |
| 674 | // pollset has been observed to be inactive, we need to move back to the |
| 675 | // active list |
Craig Tiller | e00d733 | 2017-05-01 15:43:51 +0000 | [diff] [blame] | 676 | bool is_reassigning = false; |
| 677 | if (!pollset->reassigning_neighbourhood) { |
| 678 | is_reassigning = true; |
| 679 | pollset->reassigning_neighbourhood = true; |
| 680 | pollset->neighbourhood = &g_neighbourhoods[choose_neighbourhood()]; |
| 681 | } |
| 682 | pollset_neighbourhood *neighbourhood = pollset->neighbourhood; |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 683 | gpr_mu_unlock(&pollset->mu); |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 684 | // pollset unlocked: state may change (even worker->kick_state) |
| 685 | retry_lock_neighbourhood: |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 686 | gpr_mu_lock(&neighbourhood->mu); |
| 687 | gpr_mu_lock(&pollset->mu); |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 688 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 689 | gpr_log(GPR_ERROR, "PS:%p BEGIN_REORG:%p kick_state=%s is_reassigning=%d", |
| 690 | pollset, worker, kick_state_string(worker->kick_state), |
| 691 | is_reassigning); |
| 692 | } |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 693 | if (pollset->seen_inactive) { |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 694 | if (neighbourhood != pollset->neighbourhood) { |
| 695 | gpr_mu_unlock(&neighbourhood->mu); |
| 696 | neighbourhood = pollset->neighbourhood; |
| 697 | gpr_mu_unlock(&pollset->mu); |
| 698 | goto retry_lock_neighbourhood; |
| 699 | } |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 700 | pollset->seen_inactive = false; |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 701 | if (neighbourhood->active_root == NULL) { |
| 702 | neighbourhood->active_root = pollset->next = pollset->prev = pollset; |
Sree Kuchibhotla | 0d8431a | 2017-07-18 16:21:54 -0700 | [diff] [blame] | 703 | /* TODO: sreek. Why would this worker state be other than UNKICKED |
| 704 | * here ? (since the worker isn't added to the pollset yet, there is no |
| 705 | * way it can be "found" by other threads to get kicked). */ |
| 706 | |
| 707 | /* If there is no designated poller, make this the designated poller */ |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 708 | if (worker->kick_state == UNKICKED && |
| 709 | gpr_atm_no_barrier_cas(&g_active_poller, 0, (gpr_atm)worker)) { |
| 710 | SET_KICK_STATE(worker, DESIGNATED_POLLER); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 711 | } |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 712 | } else { |
| 713 | pollset->next = neighbourhood->active_root; |
| 714 | pollset->prev = pollset->next->prev; |
| 715 | pollset->next->prev = pollset->prev->next = pollset; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 716 | } |
| 717 | } |
Craig Tiller | e00d733 | 2017-05-01 15:43:51 +0000 | [diff] [blame] | 718 | if (is_reassigning) { |
| 719 | GPR_ASSERT(pollset->reassigning_neighbourhood); |
| 720 | pollset->reassigning_neighbourhood = false; |
| 721 | } |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 722 | gpr_mu_unlock(&neighbourhood->mu); |
| 723 | } |
Sree Kuchibhotla | e6506bc | 2017-07-18 21:43:45 -0700 | [diff] [blame] | 724 | |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 725 | worker_insert(pollset, worker); |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 726 | pollset->begin_refs--; |
Sree Kuchibhotla | 949d075 | 2017-07-20 23:49:15 -0700 | [diff] [blame] | 727 | if (worker->kick_state == UNKICKED && !pollset->kicked_without_poller) { |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 728 | GPR_ASSERT(gpr_atm_no_barrier_load(&g_active_poller) != (gpr_atm)worker); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 729 | worker->initialized_cv = true; |
| 730 | gpr_cv_init(&worker->cv); |
Craig Tiller | c81512a | 2017-05-26 09:53:58 -0700 | [diff] [blame] | 731 | while (worker->kick_state == UNKICKED && !pollset->shutting_down) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 732 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 733 | gpr_log(GPR_ERROR, "PS:%p BEGIN_WAIT:%p kick_state=%s shutdown=%d", |
| 734 | pollset, worker, kick_state_string(worker->kick_state), |
| 735 | pollset->shutting_down); |
| 736 | } |
Sree Kuchibhotla | 0d8431a | 2017-07-18 16:21:54 -0700 | [diff] [blame] | 737 | |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 738 | if (gpr_cv_wait(&worker->cv, &pollset->mu, deadline) && |
| 739 | worker->kick_state == UNKICKED) { |
Sree Kuchibhotla | 0d8431a | 2017-07-18 16:21:54 -0700 | [diff] [blame] | 740 | /* If gpr_cv_wait returns true (i.e a timeout), pretend that the worker |
| 741 | received a kick */ |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 742 | SET_KICK_STATE(worker, KICKED); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 743 | } |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 744 | } |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 745 | *now = gpr_now(now->clock_type); |
| 746 | } |
Sree Kuchibhotla | 949d075 | 2017-07-20 23:49:15 -0700 | [diff] [blame] | 747 | |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 748 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Sree Kuchibhotla | 949d075 | 2017-07-20 23:49:15 -0700 | [diff] [blame] | 749 | gpr_log(GPR_ERROR, |
| 750 | "PS:%p BEGIN_DONE:%p kick_state=%s shutdown=%d " |
| 751 | "kicked_without_poller: %d", |
| 752 | pollset, worker, kick_state_string(worker->kick_state), |
| 753 | pollset->shutting_down, pollset->kicked_without_poller); |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 754 | } |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 755 | |
Sree Kuchibhotla | e6506bc | 2017-07-18 21:43:45 -0700 | [diff] [blame] | 756 | /* We release pollset lock in this function at a couple of places: |
Sree Kuchibhotla | a0616ef | 2017-07-18 23:49:49 -0700 | [diff] [blame] | 757 | * 1. Briefly when assigning pollset to a neighbourhood |
Sree Kuchibhotla | e6506bc | 2017-07-18 21:43:45 -0700 | [diff] [blame] | 758 | * 2. When doing gpr_cv_wait() |
| 759 | * It is possible that 'kicked_without_poller' was set to true during (1) and |
| 760 | * 'shutting_down' is set to true during (1) or (2). If either of them is |
| 761 | * true, this worker cannot do polling */ |
Sree Kuchibhotla | e6506bc | 2017-07-18 21:43:45 -0700 | [diff] [blame] | 762 | /* TODO(sreek): Perhaps there is a better way to handle kicked_without_poller |
| 763 | * case; especially when the worker is the DESIGNATED_POLLER */ |
| 764 | |
Sree Kuchibhotla | a0616ef | 2017-07-18 23:49:49 -0700 | [diff] [blame] | 765 | if (pollset->kicked_without_poller) { |
| 766 | pollset->kicked_without_poller = false; |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 767 | GPR_TIMER_END("begin_worker", 0); |
Sree Kuchibhotla | a0616ef | 2017-07-18 23:49:49 -0700 | [diff] [blame] | 768 | return false; |
| 769 | } |
| 770 | |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 771 | GPR_TIMER_END("begin_worker", 0); |
Sree Kuchibhotla | a0616ef | 2017-07-18 23:49:49 -0700 | [diff] [blame] | 772 | return worker->kick_state == DESIGNATED_POLLER && !pollset->shutting_down; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 773 | } |
| 774 | |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 775 | static bool check_neighbourhood_for_available_poller( |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 776 | pollset_neighbourhood *neighbourhood) { |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 777 | GPR_TIMER_BEGIN("check_neighbourhood_for_available_poller", 0); |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 778 | bool found_worker = false; |
| 779 | do { |
| 780 | grpc_pollset *inspect = neighbourhood->active_root; |
| 781 | if (inspect == NULL) { |
| 782 | break; |
| 783 | } |
| 784 | gpr_mu_lock(&inspect->mu); |
| 785 | GPR_ASSERT(!inspect->seen_inactive); |
| 786 | grpc_pollset_worker *inspect_worker = inspect->root_worker; |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 787 | if (inspect_worker != NULL) { |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 788 | do { |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 789 | switch (inspect_worker->kick_state) { |
| 790 | case UNKICKED: |
| 791 | if (gpr_atm_no_barrier_cas(&g_active_poller, 0, |
| 792 | (gpr_atm)inspect_worker)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 793 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 794 | gpr_log(GPR_DEBUG, " .. choose next poller to be %p", |
| 795 | inspect_worker); |
| 796 | } |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 797 | SET_KICK_STATE(inspect_worker, DESIGNATED_POLLER); |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 798 | if (inspect_worker->initialized_cv) { |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 799 | GPR_TIMER_MARK("signal worker", 0); |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 800 | gpr_cv_signal(&inspect_worker->cv); |
| 801 | } |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 802 | } else { |
| 803 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 804 | gpr_log(GPR_DEBUG, " .. beaten to choose next poller"); |
| 805 | } |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 806 | } |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 807 | // even if we didn't win the cas, there's a worker, we can stop |
| 808 | found_worker = true; |
| 809 | break; |
| 810 | case KICKED: |
| 811 | break; |
| 812 | case DESIGNATED_POLLER: |
| 813 | found_worker = true; // ok, so someone else found the worker, but |
| 814 | // we'll accept that |
| 815 | break; |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 816 | } |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 817 | inspect_worker = inspect_worker->next; |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 818 | } while (!found_worker && inspect_worker != inspect->root_worker); |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 819 | } |
| 820 | if (!found_worker) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 821 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 822 | gpr_log(GPR_DEBUG, " .. mark pollset %p inactive", inspect); |
| 823 | } |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 824 | inspect->seen_inactive = true; |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 825 | if (inspect == neighbourhood->active_root) { |
Craig Tiller | a95bacf | 2017-05-01 12:51:24 -0700 | [diff] [blame] | 826 | neighbourhood->active_root = |
| 827 | inspect->next == inspect ? NULL : inspect->next; |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 828 | } |
| 829 | inspect->next->prev = inspect->prev; |
| 830 | inspect->prev->next = inspect->next; |
Craig Tiller | e00d733 | 2017-05-01 15:43:51 +0000 | [diff] [blame] | 831 | inspect->next = inspect->prev = NULL; |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 832 | } |
| 833 | gpr_mu_unlock(&inspect->mu); |
| 834 | } while (!found_worker); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 835 | GPR_TIMER_END("check_neighbourhood_for_available_poller", 0); |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 836 | return found_worker; |
| 837 | } |
| 838 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 839 | static void end_worker(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, |
| 840 | grpc_pollset_worker *worker, |
| 841 | grpc_pollset_worker **worker_hdl) { |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 842 | GPR_TIMER_BEGIN("end_worker", 0); |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 843 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 844 | gpr_log(GPR_DEBUG, "PS:%p END_WORKER:%p", pollset, worker); |
| 845 | } |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 846 | if (worker_hdl != NULL) *worker_hdl = NULL; |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 847 | /* Make sure we appear kicked */ |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 848 | SET_KICK_STATE(worker, KICKED); |
Craig Tiller | 50da5ec | 2017-05-01 13:51:14 -0700 | [diff] [blame] | 849 | grpc_closure_list_move(&worker->schedule_on_end_work, |
| 850 | &exec_ctx->closure_list); |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 851 | if (gpr_atm_no_barrier_load(&g_active_poller) == (gpr_atm)worker) { |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 852 | if (worker->next != worker && worker->next->kick_state == UNKICKED) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 853 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 854 | gpr_log(GPR_DEBUG, " .. choose next poller to be peer %p", worker); |
| 855 | } |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 856 | GPR_ASSERT(worker->next->initialized_cv); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 857 | gpr_atm_no_barrier_store(&g_active_poller, (gpr_atm)worker->next); |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 858 | SET_KICK_STATE(worker->next, DESIGNATED_POLLER); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 859 | gpr_cv_signal(&worker->next->cv); |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 860 | if (grpc_exec_ctx_has_work(exec_ctx)) { |
| 861 | gpr_mu_unlock(&pollset->mu); |
| 862 | grpc_exec_ctx_flush(exec_ctx); |
| 863 | gpr_mu_lock(&pollset->mu); |
| 864 | } |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 865 | } else { |
| 866 | gpr_atm_no_barrier_store(&g_active_poller, 0); |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 867 | size_t poller_neighbourhood_idx = |
| 868 | (size_t)(pollset->neighbourhood - g_neighbourhoods); |
Craig Tiller | bb74267 | 2017-05-17 22:19:05 +0000 | [diff] [blame] | 869 | gpr_mu_unlock(&pollset->mu); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 870 | bool found_worker = false; |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 871 | bool scan_state[MAX_NEIGHBOURHOODS]; |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 872 | for (size_t i = 0; !found_worker && i < g_num_neighbourhoods; i++) { |
| 873 | pollset_neighbourhood *neighbourhood = |
| 874 | &g_neighbourhoods[(poller_neighbourhood_idx + i) % |
| 875 | g_num_neighbourhoods]; |
| 876 | if (gpr_mu_trylock(&neighbourhood->mu)) { |
| 877 | found_worker = |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 878 | check_neighbourhood_for_available_poller(neighbourhood); |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 879 | gpr_mu_unlock(&neighbourhood->mu); |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 880 | scan_state[i] = true; |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 881 | } else { |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 882 | scan_state[i] = false; |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 883 | } |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 884 | } |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 885 | for (size_t i = 0; !found_worker && i < g_num_neighbourhoods; i++) { |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 886 | if (scan_state[i]) continue; |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 887 | pollset_neighbourhood *neighbourhood = |
| 888 | &g_neighbourhoods[(poller_neighbourhood_idx + i) % |
| 889 | g_num_neighbourhoods]; |
| 890 | gpr_mu_lock(&neighbourhood->mu); |
Craig Tiller | ba550da | 2017-05-01 14:26:31 +0000 | [diff] [blame] | 891 | found_worker = check_neighbourhood_for_available_poller(neighbourhood); |
Craig Tiller | 2acab6e | 2017-04-30 23:06:33 +0000 | [diff] [blame] | 892 | gpr_mu_unlock(&neighbourhood->mu); |
Craig Tiller | bbf4c7a | 2017-04-28 15:12:10 -0700 | [diff] [blame] | 893 | } |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 894 | grpc_exec_ctx_flush(exec_ctx); |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 895 | gpr_mu_lock(&pollset->mu); |
| 896 | } |
Craig Tiller | 50da5ec | 2017-05-01 13:51:14 -0700 | [diff] [blame] | 897 | } else if (grpc_exec_ctx_has_work(exec_ctx)) { |
| 898 | gpr_mu_unlock(&pollset->mu); |
| 899 | grpc_exec_ctx_flush(exec_ctx); |
| 900 | gpr_mu_lock(&pollset->mu); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 901 | } |
| 902 | if (worker->initialized_cv) { |
| 903 | gpr_cv_destroy(&worker->cv); |
| 904 | } |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 905 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 906 | gpr_log(GPR_DEBUG, " .. remove worker"); |
| 907 | } |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 908 | if (EMPTIED == worker_remove(pollset, worker)) { |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 909 | pollset_maybe_finish_shutdown(exec_ctx, pollset); |
| 910 | } |
Craig Tiller | a4b8eb0 | 2017-04-29 00:13:52 +0000 | [diff] [blame] | 911 | GPR_ASSERT(gpr_atm_no_barrier_load(&g_active_poller) != (gpr_atm)worker); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 912 | GPR_TIMER_END("end_worker", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 913 | } |
| 914 | |
| 915 | /* pollset->po.mu lock must be held by the caller before calling this. |
| 916 | The function pollset_work() may temporarily release the lock (pollset->po.mu) |
| 917 | during the course of its execution but it will always re-acquire the lock and |
| 918 | ensure that it is held by the time the function returns */ |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 919 | static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *ps, |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 920 | grpc_pollset_worker **worker_hdl, |
| 921 | gpr_timespec now, gpr_timespec deadline) { |
| 922 | grpc_pollset_worker worker; |
| 923 | grpc_error *error = GRPC_ERROR_NONE; |
| 924 | static const char *err_desc = "pollset_work"; |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 925 | GPR_TIMER_BEGIN("pollset_work", 0); |
Sree Kuchibhotla | b154cd1 | 2017-08-25 10:33:41 -0700 | [diff] [blame] | 926 | if (ps->kicked_without_poller) { |
| 927 | ps->kicked_without_poller = false; |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 928 | GPR_TIMER_END("pollset_work", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 929 | return GRPC_ERROR_NONE; |
| 930 | } |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 931 | |
| 932 | if (begin_worker(ps, &worker, worker_hdl, &now, deadline)) { |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 933 | GPR_ASSERT(gpr_atm_no_barrier_cas(&g_cs, 0, 1)); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 934 | gpr_tls_set(&g_current_thread_pollset, (intptr_t)ps); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 935 | gpr_tls_set(&g_current_thread_worker, (intptr_t)&worker); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 936 | GPR_ASSERT(!ps->shutting_down); |
| 937 | GPR_ASSERT(!ps->seen_inactive); |
| 938 | |
| 939 | gpr_mu_unlock(&ps->mu); /* unlock */ |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 940 | /* This is the designated polling thread at this point and should ideally do |
| 941 | polling. However, if there are unprocessed events left from a previous |
| 942 | call to do_epoll_wait(), skip calling epoll_wait() in this iteration and |
| 943 | process the pending epoll events. |
| 944 | |
| 945 | The reason for decoupling do_epoll_wait and process_epoll_events is to |
| 946 | better distrubute the work (i.e handling epoll events) across multiple |
| 947 | threads |
| 948 | |
| 949 | process_epoll_events() returns very quickly: It just queues the work on |
| 950 | exec_ctx but does not execute it (the actual exectution or more |
| 951 | accurately grpc_exec_ctx_flush() happens in end_worker() AFTER selecting |
| 952 | a designated poller). So we are not waiting long periods without a |
| 953 | designated poller */ |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 954 | if (gpr_atm_acq_load(&g_epoll_set.cursor) == |
| 955 | gpr_atm_acq_load(&g_epoll_set.num_events)) { |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 956 | append_error(&error, do_epoll_wait(exec_ctx, ps, now, deadline), |
| 957 | err_desc); |
| 958 | } |
| 959 | append_error(&error, process_epoll_events(exec_ctx, ps), err_desc); |
| 960 | |
| 961 | gpr_mu_lock(&ps->mu); /* lock */ |
| 962 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 963 | gpr_tls_set(&g_current_thread_worker, 0); |
Sree Kuchibhotla | a92a9cc | 2017-08-27 14:02:15 -0700 | [diff] [blame^] | 964 | GPR_ASSERT(gpr_atm_no_barrier_cas(&g_cs, 1, 0)); |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 965 | } else { |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 966 | gpr_tls_set(&g_current_thread_pollset, (intptr_t)ps); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 967 | } |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 968 | end_worker(exec_ctx, ps, &worker, worker_hdl); |
| 969 | |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 970 | gpr_tls_set(&g_current_thread_pollset, 0); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 971 | GPR_TIMER_END("pollset_work", 0); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 972 | return error; |
| 973 | } |
| 974 | |
| 975 | static grpc_error *pollset_kick(grpc_pollset *pollset, |
| 976 | grpc_pollset_worker *specific_worker) { |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 977 | GPR_TIMER_BEGIN("pollset_kick", 0); |
| 978 | grpc_error *ret_err = GRPC_ERROR_NONE; |
Craig Tiller | b89bac0 | 2017-05-26 15:20:32 +0000 | [diff] [blame] | 979 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 980 | gpr_strvec log; |
| 981 | gpr_strvec_init(&log); |
| 982 | char *tmp; |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 983 | gpr_asprintf( |
| 984 | &tmp, "PS:%p KICK:%p curps=%p curworker=%p root=%p", pollset, |
| 985 | specific_worker, (void *)gpr_tls_get(&g_current_thread_pollset), |
| 986 | (void *)gpr_tls_get(&g_current_thread_worker), pollset->root_worker); |
Craig Tiller | b89bac0 | 2017-05-26 15:20:32 +0000 | [diff] [blame] | 987 | gpr_strvec_add(&log, tmp); |
| 988 | if (pollset->root_worker != NULL) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 989 | gpr_asprintf(&tmp, " {kick_state=%s next=%p {kick_state=%s}}", |
| 990 | kick_state_string(pollset->root_worker->kick_state), |
| 991 | pollset->root_worker->next, |
| 992 | kick_state_string(pollset->root_worker->next->kick_state)); |
Craig Tiller | b89bac0 | 2017-05-26 15:20:32 +0000 | [diff] [blame] | 993 | gpr_strvec_add(&log, tmp); |
| 994 | } |
| 995 | if (specific_worker != NULL) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 996 | gpr_asprintf(&tmp, " worker_kick_state=%s", |
| 997 | kick_state_string(specific_worker->kick_state)); |
Craig Tiller | b89bac0 | 2017-05-26 15:20:32 +0000 | [diff] [blame] | 998 | gpr_strvec_add(&log, tmp); |
| 999 | } |
| 1000 | tmp = gpr_strvec_flatten(&log, NULL); |
| 1001 | gpr_strvec_destroy(&log); |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1002 | gpr_log(GPR_ERROR, "%s", tmp); |
Craig Tiller | b89bac0 | 2017-05-26 15:20:32 +0000 | [diff] [blame] | 1003 | gpr_free(tmp); |
| 1004 | } |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1005 | if (specific_worker == NULL) { |
| 1006 | if (gpr_tls_get(&g_current_thread_pollset) != (intptr_t)pollset) { |
Craig Tiller | 375eb25 | 2017-04-27 23:29:12 +0000 | [diff] [blame] | 1007 | grpc_pollset_worker *root_worker = pollset->root_worker; |
| 1008 | if (root_worker == NULL) { |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1009 | pollset->kicked_without_poller = true; |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1010 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1011 | gpr_log(GPR_ERROR, " .. kicked_without_poller"); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1012 | } |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1013 | goto done; |
Craig Tiller | 375eb25 | 2017-04-27 23:29:12 +0000 | [diff] [blame] | 1014 | } |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 1015 | grpc_pollset_worker *next_worker = root_worker->next; |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1016 | if (root_worker->kick_state == KICKED) { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1017 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1018 | gpr_log(GPR_ERROR, " .. already kicked %p", root_worker); |
| 1019 | } |
| 1020 | SET_KICK_STATE(root_worker, KICKED); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1021 | goto done; |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1022 | } else if (next_worker->kick_state == KICKED) { |
| 1023 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 1024 | gpr_log(GPR_ERROR, " .. already kicked %p", next_worker); |
| 1025 | } |
| 1026 | SET_KICK_STATE(next_worker, KICKED); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1027 | goto done; |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1028 | } else if (root_worker == |
| 1029 | next_worker && // only try and wake up a poller if |
| 1030 | // there is no next worker |
| 1031 | root_worker == (grpc_pollset_worker *)gpr_atm_no_barrier_load( |
| 1032 | &g_active_poller)) { |
| 1033 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 1034 | gpr_log(GPR_ERROR, " .. kicked %p", root_worker); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1035 | } |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1036 | SET_KICK_STATE(root_worker, KICKED); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1037 | ret_err = grpc_wakeup_fd_wakeup(&global_wakeup_fd); |
| 1038 | goto done; |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 1039 | } else if (next_worker->kick_state == UNKICKED) { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1040 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1041 | gpr_log(GPR_ERROR, " .. kicked %p", next_worker); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1042 | } |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 1043 | GPR_ASSERT(next_worker->initialized_cv); |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1044 | SET_KICK_STATE(next_worker, KICKED); |
Craig Tiller | 375eb25 | 2017-04-27 23:29:12 +0000 | [diff] [blame] | 1045 | gpr_cv_signal(&next_worker->cv); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1046 | goto done; |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1047 | } else if (next_worker->kick_state == DESIGNATED_POLLER) { |
| 1048 | if (root_worker->kick_state != DESIGNATED_POLLER) { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1049 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1050 | gpr_log( |
| 1051 | GPR_ERROR, |
| 1052 | " .. kicked root non-poller %p (initialized_cv=%d) (poller=%p)", |
| 1053 | root_worker, root_worker->initialized_cv, next_worker); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1054 | } |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1055 | SET_KICK_STATE(root_worker, KICKED); |
| 1056 | if (root_worker->initialized_cv) { |
| 1057 | gpr_cv_signal(&root_worker->cv); |
| 1058 | } |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1059 | goto done; |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1060 | } else { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1061 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1062 | gpr_log(GPR_ERROR, " .. non-root poller %p (root=%p)", next_worker, |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1063 | root_worker); |
| 1064 | } |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1065 | SET_KICK_STATE(next_worker, KICKED); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1066 | ret_err = grpc_wakeup_fd_wakeup(&global_wakeup_fd); |
| 1067 | goto done; |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1068 | } |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 1069 | } else { |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1070 | GPR_ASSERT(next_worker->kick_state == KICKED); |
| 1071 | SET_KICK_STATE(next_worker, KICKED); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1072 | goto done; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1073 | } |
| 1074 | } else { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1075 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
| 1076 | gpr_log(GPR_ERROR, " .. kicked while waking up"); |
| 1077 | } |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1078 | goto done; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1079 | } |
Craig Tiller | 43bf259 | 2017-04-28 23:21:01 +0000 | [diff] [blame] | 1080 | } else if (specific_worker->kick_state == KICKED) { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1081 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1082 | gpr_log(GPR_ERROR, " .. specific worker already kicked"); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1083 | } |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1084 | goto done; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1085 | } else if (gpr_tls_get(&g_current_thread_worker) == |
| 1086 | (intptr_t)specific_worker) { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1087 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1088 | gpr_log(GPR_ERROR, " .. mark %p kicked", specific_worker); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1089 | } |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1090 | SET_KICK_STATE(specific_worker, KICKED); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1091 | goto done; |
Craig Tiller | 32f90ee | 2017-04-28 12:46:41 -0700 | [diff] [blame] | 1092 | } else if (specific_worker == |
| 1093 | (grpc_pollset_worker *)gpr_atm_no_barrier_load(&g_active_poller)) { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1094 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1095 | gpr_log(GPR_ERROR, " .. kick active poller"); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1096 | } |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1097 | SET_KICK_STATE(specific_worker, KICKED); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1098 | ret_err = grpc_wakeup_fd_wakeup(&global_wakeup_fd); |
| 1099 | goto done; |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 1100 | } else if (specific_worker->initialized_cv) { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1101 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1102 | gpr_log(GPR_ERROR, " .. kick waiting worker"); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1103 | } |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1104 | SET_KICK_STATE(specific_worker, KICKED); |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1105 | gpr_cv_signal(&specific_worker->cv); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1106 | goto done; |
Craig Tiller | 8502ecb | 2017-04-28 14:22:01 -0700 | [diff] [blame] | 1107 | } else { |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1108 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
Craig Tiller | 830e82a | 2017-05-31 16:26:27 -0700 | [diff] [blame] | 1109 | gpr_log(GPR_ERROR, " .. kick non-waiting worker"); |
Craig Tiller | 75aef7f | 2017-05-26 08:26:08 -0700 | [diff] [blame] | 1110 | } |
Craig Tiller | 55624a3 | 2017-05-26 08:14:44 -0700 | [diff] [blame] | 1111 | SET_KICK_STATE(specific_worker, KICKED); |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1112 | goto done; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1113 | } |
yang-g | df92a64 | 2017-08-21 22:38:45 -0700 | [diff] [blame] | 1114 | done: |
| 1115 | GPR_TIMER_END("pollset_kick", 0); |
| 1116 | return ret_err; |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1117 | } |
| 1118 | |
| 1119 | static void pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, |
| 1120 | grpc_fd *fd) {} |
| 1121 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1122 | /******************************************************************************* |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1123 | * Pollset-set Definitions |
| 1124 | */ |
| 1125 | |
| 1126 | static grpc_pollset_set *pollset_set_create(void) { |
| 1127 | return (grpc_pollset_set *)((intptr_t)0xdeafbeef); |
| 1128 | } |
| 1129 | |
| 1130 | static void pollset_set_destroy(grpc_exec_ctx *exec_ctx, |
| 1131 | grpc_pollset_set *pss) {} |
| 1132 | |
| 1133 | static void pollset_set_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss, |
| 1134 | grpc_fd *fd) {} |
| 1135 | |
| 1136 | static void pollset_set_del_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss, |
| 1137 | grpc_fd *fd) {} |
| 1138 | |
| 1139 | static void pollset_set_add_pollset(grpc_exec_ctx *exec_ctx, |
| 1140 | grpc_pollset_set *pss, grpc_pollset *ps) {} |
| 1141 | |
| 1142 | static void pollset_set_del_pollset(grpc_exec_ctx *exec_ctx, |
| 1143 | grpc_pollset_set *pss, grpc_pollset *ps) {} |
| 1144 | |
| 1145 | static void pollset_set_add_pollset_set(grpc_exec_ctx *exec_ctx, |
| 1146 | grpc_pollset_set *bag, |
| 1147 | grpc_pollset_set *item) {} |
| 1148 | |
| 1149 | static void pollset_set_del_pollset_set(grpc_exec_ctx *exec_ctx, |
| 1150 | grpc_pollset_set *bag, |
| 1151 | grpc_pollset_set *item) {} |
| 1152 | |
| 1153 | /******************************************************************************* |
| 1154 | * Event engine binding |
| 1155 | */ |
| 1156 | |
| 1157 | static void shutdown_engine(void) { |
| 1158 | fd_global_shutdown(); |
| 1159 | pollset_global_shutdown(); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 1160 | epoll_set_shutdown(); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1161 | } |
| 1162 | |
| 1163 | static const grpc_event_engine_vtable vtable = { |
| 1164 | .pollset_size = sizeof(grpc_pollset), |
| 1165 | |
| 1166 | .fd_create = fd_create, |
| 1167 | .fd_wrapped_fd = fd_wrapped_fd, |
| 1168 | .fd_orphan = fd_orphan, |
| 1169 | .fd_shutdown = fd_shutdown, |
| 1170 | .fd_is_shutdown = fd_is_shutdown, |
| 1171 | .fd_notify_on_read = fd_notify_on_read, |
| 1172 | .fd_notify_on_write = fd_notify_on_write, |
| 1173 | .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset, |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1174 | |
| 1175 | .pollset_init = pollset_init, |
| 1176 | .pollset_shutdown = pollset_shutdown, |
| 1177 | .pollset_destroy = pollset_destroy, |
| 1178 | .pollset_work = pollset_work, |
| 1179 | .pollset_kick = pollset_kick, |
| 1180 | .pollset_add_fd = pollset_add_fd, |
| 1181 | |
| 1182 | .pollset_set_create = pollset_set_create, |
| 1183 | .pollset_set_destroy = pollset_set_destroy, |
| 1184 | .pollset_set_add_pollset = pollset_set_add_pollset, |
| 1185 | .pollset_set_del_pollset = pollset_set_del_pollset, |
| 1186 | .pollset_set_add_pollset_set = pollset_set_add_pollset_set, |
| 1187 | .pollset_set_del_pollset_set = pollset_set_del_pollset_set, |
| 1188 | .pollset_set_add_fd = pollset_set_add_fd, |
| 1189 | .pollset_set_del_fd = pollset_set_del_fd, |
| 1190 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1191 | .shutdown_engine = shutdown_engine, |
| 1192 | }; |
| 1193 | |
| 1194 | /* It is possible that GLIBC has epoll but the underlying kernel doesn't. |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 1195 | * Create epoll_fd (epoll_set_init() takes care of that) to make sure epoll |
| 1196 | * support is available */ |
Craig Tiller | 6f0af49 | 2017-04-27 19:26:16 +0000 | [diff] [blame] | 1197 | const grpc_event_engine_vtable *grpc_init_epoll1_linux(bool explicit_request) { |
Sree Kuchibhotla | 107840f | 2017-07-24 18:45:09 -0700 | [diff] [blame] | 1198 | if (!explicit_request) { |
| 1199 | return NULL; |
| 1200 | } |
| 1201 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1202 | if (!grpc_has_wakeup_fd()) { |
| 1203 | return NULL; |
| 1204 | } |
| 1205 | |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 1206 | if (!epoll_set_init()) { |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1207 | return NULL; |
| 1208 | } |
| 1209 | |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1210 | fd_global_init(); |
| 1211 | |
| 1212 | if (!GRPC_LOG_IF_ERROR("pollset_global_init", pollset_global_init())) { |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 1213 | fd_global_shutdown(); |
Sree Kuchibhotla | 5efc913 | 2017-08-17 14:10:38 -0700 | [diff] [blame] | 1214 | epoll_set_shutdown(); |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1215 | return NULL; |
| 1216 | } |
| 1217 | |
| 1218 | return &vtable; |
| 1219 | } |
| 1220 | |
| 1221 | #else /* defined(GRPC_LINUX_EPOLL) */ |
| 1222 | #if defined(GRPC_POSIX_SOCKET) |
| 1223 | #include "src/core/lib/iomgr/ev_posix.h" |
| 1224 | /* If GRPC_LINUX_EPOLL is not defined, it means epoll is not available. Return |
| 1225 | * NULL */ |
Craig Tiller | 9ddb315 | 2017-04-27 21:32:56 +0000 | [diff] [blame] | 1226 | const grpc_event_engine_vtable *grpc_init_epoll1_linux(bool explicit_request) { |
| 1227 | return NULL; |
| 1228 | } |
Craig Tiller | c67cc99 | 2017-04-27 10:15:51 -0700 | [diff] [blame] | 1229 | #endif /* defined(GRPC_POSIX_SOCKET) */ |
| 1230 | #endif /* !defined(GRPC_LINUX_EPOLL) */ |