Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1 | /* |
| 2 | * |
Jan Tattermusch | 7897ae9 | 2017-06-07 22:57:36 +0200 | [diff] [blame] | 3 | * Copyright 2016 gRPC authors. |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -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 |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -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 |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -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. |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 16 | * |
| 17 | */ |
| 18 | |
murgatroid99 | 5407089 | 2016-08-08 17:01:18 -0700 | [diff] [blame] | 19 | #include "src/core/lib/iomgr/port.h" |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 20 | |
Sree Kuchibhotla | 76a0795 | 2016-06-22 15:09:06 -0700 | [diff] [blame] | 21 | /* This polling engine is only relevant on linux kernels supporting epoll() */ |
murgatroid99 | 623dd4f | 2016-08-08 17:31:27 -0700 | [diff] [blame] | 22 | #ifdef GRPC_LINUX_EPOLL |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 23 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 24 | #include "src/core/lib/iomgr/ev_epollsig_linux.h" |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 25 | |
| 26 | #include <assert.h> |
| 27 | #include <errno.h> |
| 28 | #include <poll.h> |
Sree Kuchibhotla | 4998e30 | 2016-08-16 07:26:31 -0700 | [diff] [blame] | 29 | #include <pthread.h> |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 30 | #include <signal.h> |
| 31 | #include <string.h> |
| 32 | #include <sys/epoll.h> |
| 33 | #include <sys/socket.h> |
| 34 | #include <unistd.h> |
| 35 | |
| 36 | #include <grpc/support/alloc.h> |
| 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" |
Craig Tiller | 376887d | 2017-04-06 08:27:03 -0700 | [diff] [blame] | 44 | #include "src/core/lib/iomgr/lockfree_event.h" |
Craig Tiller | 185f6c9 | 2017-03-17 08:33:19 -0700 | [diff] [blame] | 45 | #include "src/core/lib/iomgr/timer.h" |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 46 | #include "src/core/lib/iomgr/wakeup_fd_posix.h" |
| 47 | #include "src/core/lib/profiling/timers.h" |
| 48 | #include "src/core/lib/support/block_annotate.h" |
| 49 | |
Craig Tiller | e24b24d | 2017-04-06 16:05:45 -0700 | [diff] [blame] | 50 | #define GRPC_POLLSET_KICK_BROADCAST ((grpc_pollset_worker *)1) |
| 51 | |
Craig Tiller | 2d1e8cd | 2017-05-17 12:41:44 -0700 | [diff] [blame] | 52 | #define GRPC_POLLING_TRACE(...) \ |
Craig Tiller | bc0ab08 | 2017-05-05 10:42:44 -0700 | [diff] [blame] | 53 | if (GRPC_TRACER_ON(grpc_polling_trace)) { \ |
Craig Tiller | 2d1e8cd | 2017-05-17 12:41:44 -0700 | [diff] [blame] | 54 | gpr_log(GPR_INFO, __VA_ARGS__); \ |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 55 | } |
| 56 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 57 | static int grpc_wakeup_signal = -1; |
| 58 | static bool is_grpc_wakeup_signal_initialized = false; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 59 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 60 | /* Implements the function defined in grpc_posix.h. This function might be |
| 61 | * called before even calling grpc_init() to set either a different signal to |
| 62 | * use. If signum == -1, then the use of signals is disabled */ |
| 63 | void grpc_use_signal(int signum) { |
| 64 | grpc_wakeup_signal = signum; |
| 65 | is_grpc_wakeup_signal_initialized = true; |
| 66 | |
| 67 | if (grpc_wakeup_signal < 0) { |
| 68 | gpr_log(GPR_INFO, |
| 69 | "Use of signals is disabled. Epoll engine will not be used"); |
| 70 | } else { |
| 71 | gpr_log(GPR_INFO, "epoll engine will be using signal: %d", |
| 72 | grpc_wakeup_signal); |
| 73 | } |
| 74 | } |
| 75 | |
| 76 | struct polling_island; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 77 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 78 | typedef enum { |
| 79 | POLL_OBJ_FD, |
| 80 | POLL_OBJ_POLLSET, |
| 81 | POLL_OBJ_POLLSET_SET |
| 82 | } poll_obj_type; |
| 83 | |
| 84 | typedef struct poll_obj { |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame^] | 85 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 86 | poll_obj_type obj_type; |
| 87 | #endif |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 88 | gpr_mu mu; |
| 89 | struct polling_island *pi; |
| 90 | } poll_obj; |
| 91 | |
| 92 | const char *poll_obj_string(poll_obj_type po_type) { |
| 93 | switch (po_type) { |
| 94 | case POLL_OBJ_FD: |
| 95 | return "fd"; |
| 96 | case POLL_OBJ_POLLSET: |
| 97 | return "pollset"; |
| 98 | case POLL_OBJ_POLLSET_SET: |
| 99 | return "pollset_set"; |
| 100 | } |
| 101 | |
| 102 | GPR_UNREACHABLE_CODE(return "UNKNOWN"); |
| 103 | } |
| 104 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 105 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 106 | * Fd Declarations |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 107 | */ |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 108 | |
| 109 | #define FD_FROM_PO(po) ((grpc_fd *)(po)) |
| 110 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 111 | struct grpc_fd { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 112 | poll_obj po; |
| 113 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 114 | int fd; |
| 115 | /* refst format: |
Sree Kuchibhotla | 5098f91 | 2016-05-31 10:58:17 -0700 | [diff] [blame] | 116 | bit 0 : 1=Active / 0=Orphaned |
| 117 | bits 1-n : refcount |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 118 | Ref/Unref by two to avoid altering the orphaned bit */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 119 | gpr_atm refst; |
| 120 | |
Sree Kuchibhotla | 9998338 | 2017-02-12 17:03:27 -0800 | [diff] [blame] | 121 | /* The fd is either closed or we relinquished control of it. In either |
| 122 | cases, this indicates that the 'fd' on this structure is no longer |
| 123 | valid */ |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 124 | bool orphaned; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 125 | |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 126 | gpr_atm read_closure; |
| 127 | gpr_atm write_closure; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 128 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 129 | struct grpc_fd *freelist_next; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 130 | grpc_closure *on_done_closure; |
| 131 | |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 132 | /* The pollset that last noticed that the fd is readable. The actual type |
| 133 | * stored in this is (grpc_pollset *) */ |
| 134 | gpr_atm read_notifier_pollset; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 135 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 136 | grpc_iomgr_object iomgr_object; |
| 137 | }; |
| 138 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 139 | /* Reference counting for fds */ |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 140 | #ifndef NDEBUG |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 141 | static void fd_ref(grpc_fd *fd, const char *reason, const char *file, int line); |
| 142 | static void fd_unref(grpc_fd *fd, const char *reason, const char *file, |
| 143 | int line); |
| 144 | #define GRPC_FD_REF(fd, reason) fd_ref(fd, reason, __FILE__, __LINE__) |
| 145 | #define GRPC_FD_UNREF(fd, reason) fd_unref(fd, reason, __FILE__, __LINE__) |
| 146 | #else |
| 147 | static void fd_ref(grpc_fd *fd); |
| 148 | static void fd_unref(grpc_fd *fd); |
| 149 | #define GRPC_FD_REF(fd, reason) fd_ref(fd) |
| 150 | #define GRPC_FD_UNREF(fd, reason) fd_unref(fd) |
| 151 | #endif |
| 152 | |
| 153 | static void fd_global_init(void); |
| 154 | static void fd_global_shutdown(void); |
| 155 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 156 | /******************************************************************************* |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 157 | * Polling island Declarations |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 158 | */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 159 | |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 160 | #ifndef NDEBUG |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 161 | |
Sree Kuchibhotla | 6a29545 | 2016-06-23 15:53:10 -0700 | [diff] [blame] | 162 | #define PI_ADD_REF(p, r) pi_add_ref_dbg((p), (r), __FILE__, __LINE__) |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 163 | #define PI_UNREF(exec_ctx, p, r) \ |
| 164 | pi_unref_dbg((exec_ctx), (p), (r), __FILE__, __LINE__) |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 165 | |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 166 | #else |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 167 | |
Sree Kuchibhotla | 6a29545 | 2016-06-23 15:53:10 -0700 | [diff] [blame] | 168 | #define PI_ADD_REF(p, r) pi_add_ref((p)) |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 169 | #define PI_UNREF(exec_ctx, p, r) pi_unref((exec_ctx), (p)) |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 170 | |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 171 | #endif |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 172 | |
Craig Tiller | 460502e | 2016-10-13 10:02:08 -0700 | [diff] [blame] | 173 | /* This is also used as grpc_workqueue (by directly casing it) */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 174 | typedef struct polling_island { |
| 175 | gpr_mu mu; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 176 | /* Ref count. Use PI_ADD_REF() and PI_UNREF() macros to increment/decrement |
| 177 | the refcount. |
| 178 | Once the ref count becomes zero, this structure is destroyed which means |
| 179 | we should ensure that there is never a scenario where a PI_ADD_REF() is |
| 180 | racing with a PI_UNREF() that just made the ref_count zero. */ |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 181 | gpr_atm ref_count; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 182 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 183 | /* Pointer to the polling_island this merged into. |
| 184 | * merged_to value is only set once in polling_island's lifetime (and that too |
| 185 | * only if the island is merged with another island). Because of this, we can |
| 186 | * use gpr_atm type here so that we can do atomic access on this and reduce |
| 187 | * lock contention on 'mu' mutex. |
| 188 | * |
| 189 | * Note that if this field is not NULL (i.e not 0), all the remaining fields |
| 190 | * (except mu and ref_count) are invalid and must be ignored. */ |
| 191 | gpr_atm merged_to; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 192 | |
Craig Tiller | 460502e | 2016-10-13 10:02:08 -0700 | [diff] [blame] | 193 | /* Number of threads currently polling on this island */ |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 194 | gpr_atm poller_count; |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 195 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 196 | /* The fd of the underlying epoll set */ |
| 197 | int epoll_fd; |
| 198 | |
| 199 | /* The file descriptors in the epoll set */ |
| 200 | size_t fd_cnt; |
| 201 | size_t fd_capacity; |
| 202 | grpc_fd **fds; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 203 | } polling_island; |
| 204 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 205 | /******************************************************************************* |
| 206 | * Pollset Declarations |
| 207 | */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 208 | struct grpc_pollset_worker { |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 209 | /* Thread id of this worker */ |
| 210 | pthread_t pt_id; |
| 211 | |
| 212 | /* Used to prevent a worker from getting kicked multiple times */ |
| 213 | gpr_atm is_kicked; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 214 | struct grpc_pollset_worker *next; |
| 215 | struct grpc_pollset_worker *prev; |
| 216 | }; |
| 217 | |
| 218 | struct grpc_pollset { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 219 | poll_obj po; |
| 220 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 221 | grpc_pollset_worker root_worker; |
| 222 | bool kicked_without_pollers; |
| 223 | |
| 224 | bool shutting_down; /* Is the pollset shutting down ? */ |
| 225 | bool finish_shutdown_called; /* Is the 'finish_shutdown_locked()' called ? */ |
| 226 | grpc_closure *shutdown_done; /* Called after after shutdown is complete */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 227 | }; |
| 228 | |
| 229 | /******************************************************************************* |
| 230 | * Pollset-set Declarations |
| 231 | */ |
| 232 | struct grpc_pollset_set { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 233 | poll_obj po; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 234 | }; |
| 235 | |
| 236 | /******************************************************************************* |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 237 | * Common helpers |
| 238 | */ |
| 239 | |
Craig Tiller | f975f74 | 2016-07-01 14:56:27 -0700 | [diff] [blame] | 240 | static bool append_error(grpc_error **composite, grpc_error *error, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 241 | const char *desc) { |
Craig Tiller | f975f74 | 2016-07-01 14:56:27 -0700 | [diff] [blame] | 242 | if (error == GRPC_ERROR_NONE) return true; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 243 | if (*composite == GRPC_ERROR_NONE) { |
Noah Eisen | 3005ce8 | 2017-03-14 13:38:41 -0700 | [diff] [blame] | 244 | *composite = GRPC_ERROR_CREATE_FROM_COPIED_STRING(desc); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 245 | } |
| 246 | *composite = grpc_error_add_child(*composite, error); |
Craig Tiller | f975f74 | 2016-07-01 14:56:27 -0700 | [diff] [blame] | 247 | return false; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 248 | } |
| 249 | |
| 250 | /******************************************************************************* |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 251 | * Polling island Definitions |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 252 | */ |
| 253 | |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 254 | /* The wakeup fd that is used to wake up all threads in a Polling island. This |
| 255 | is useful in the polling island merge operation where we need to wakeup all |
| 256 | the threads currently polling the smaller polling island (so that they can |
| 257 | start polling the new/merged polling island) |
| 258 | |
| 259 | NOTE: This fd is initialized to be readable and MUST NOT be consumed i.e the |
| 260 | threads that woke up MUST NOT call grpc_wakeup_fd_consume_wakeup() */ |
| 261 | static grpc_wakeup_fd polling_island_wakeup_fd; |
| 262 | |
Craig Tiller | 2e62013 | 2016-10-10 15:27:44 -0700 | [diff] [blame] | 263 | /* The polling island being polled right now. |
| 264 | See comments in workqueue_maybe_wakeup for why this is tracked. */ |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 265 | static __thread polling_island *g_current_thread_polling_island; |
| 266 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 267 | /* Forward declaration */ |
Craig Tiller | 2b49ea9 | 2016-07-01 13:21:27 -0700 | [diff] [blame] | 268 | static void polling_island_delete(grpc_exec_ctx *exec_ctx, polling_island *pi); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 269 | |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 270 | #ifdef GRPC_TSAN |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 271 | /* Currently TSAN may incorrectly flag data races between epoll_ctl and |
| 272 | epoll_wait for any grpc_fd structs that are added to the epoll set via |
| 273 | epoll_ctl and are returned (within a very short window) via epoll_wait(). |
| 274 | |
| 275 | To work-around this race, we establish a happens-before relation between |
| 276 | the code just-before epoll_ctl() and the code after epoll_wait() by using |
| 277 | this atomic */ |
| 278 | gpr_atm g_epoll_sync; |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 279 | #endif /* defined(GRPC_TSAN) */ |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 280 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 281 | static void pi_add_ref(polling_island *pi); |
| 282 | static void pi_unref(grpc_exec_ctx *exec_ctx, polling_island *pi); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 283 | |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 284 | #ifndef NDEBUG |
Craig Tiller | a10b0b1 | 2016-09-09 16:20:07 -0700 | [diff] [blame] | 285 | static void pi_add_ref_dbg(polling_island *pi, const char *reason, |
| 286 | const char *file, int line) { |
ncteisen | f8061e8 | 2017-06-09 10:44:42 -0700 | [diff] [blame] | 287 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 288 | gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count); |
| 289 | gpr_log(GPR_DEBUG, "Add ref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR |
| 290 | " (%s) - (%s, %d)", |
| 291 | pi, old_cnt, old_cnt + 1, reason, file, line); |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 292 | } |
| 293 | pi_add_ref(pi); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 294 | } |
| 295 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 296 | static void pi_unref_dbg(grpc_exec_ctx *exec_ctx, polling_island *pi, |
Craig Tiller | a10b0b1 | 2016-09-09 16:20:07 -0700 | [diff] [blame] | 297 | const char *reason, const char *file, int line) { |
ncteisen | f8061e8 | 2017-06-09 10:44:42 -0700 | [diff] [blame] | 298 | if (GRPC_TRACER_ON(grpc_polling_trace)) { |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 299 | gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count); |
| 300 | gpr_log(GPR_DEBUG, "Unref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR |
| 301 | " (%s) - (%s, %d)", |
| 302 | pi, old_cnt, (old_cnt - 1), reason, file, line); |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 303 | } |
| 304 | pi_unref(exec_ctx, pi); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 305 | } |
| 306 | #endif |
| 307 | |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 308 | static void pi_add_ref(polling_island *pi) { |
| 309 | gpr_atm_no_barrier_fetch_add(&pi->ref_count, 1); |
| 310 | } |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 311 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 312 | static void pi_unref(grpc_exec_ctx *exec_ctx, polling_island *pi) { |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 313 | /* If ref count went to zero, delete the polling island. |
Sree Kuchibhotla | 6a29545 | 2016-06-23 15:53:10 -0700 | [diff] [blame] | 314 | Note that this deletion not be done under a lock. Once the ref count goes |
| 315 | to zero, we are guaranteed that no one else holds a reference to the |
| 316 | polling island (and that there is no racing pi_add_ref() call either). |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 317 | |
| 318 | Also, if we are deleting the polling island and the merged_to field is |
| 319 | non-empty, we should remove a ref to the merged_to polling island |
| 320 | */ |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 321 | if (1 == gpr_atm_full_fetch_add(&pi->ref_count, -1)) { |
| 322 | polling_island *next = (polling_island *)gpr_atm_acq_load(&pi->merged_to); |
| 323 | polling_island_delete(exec_ctx, pi); |
| 324 | if (next != NULL) { |
| 325 | PI_UNREF(exec_ctx, next, "pi_delete"); /* Recursive call */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 326 | } |
| 327 | } |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 328 | } |
| 329 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 330 | /* The caller is expected to hold pi->mu lock before calling this function */ |
| 331 | static void polling_island_add_fds_locked(polling_island *pi, grpc_fd **fds, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 332 | size_t fd_count, bool add_fd_refs, |
| 333 | grpc_error **error) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 334 | int err; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 335 | size_t i; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 336 | struct epoll_event ev; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 337 | char *err_msg; |
| 338 | const char *err_desc = "polling_island_add_fds"; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 339 | |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 340 | #ifdef GRPC_TSAN |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 341 | /* See the definition of g_epoll_sync for more context */ |
Sree Kuchibhotla | 0224dcc | 2016-06-22 18:04:00 -0700 | [diff] [blame] | 342 | gpr_atm_rel_store(&g_epoll_sync, (gpr_atm)0); |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 343 | #endif /* defined(GRPC_TSAN) */ |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 344 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 345 | for (i = 0; i < fd_count; i++) { |
| 346 | ev.events = (uint32_t)(EPOLLIN | EPOLLOUT | EPOLLET); |
| 347 | ev.data.ptr = fds[i]; |
| 348 | err = epoll_ctl(pi->epoll_fd, EPOLL_CTL_ADD, fds[i]->fd, &ev); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 349 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 350 | if (err < 0) { |
| 351 | if (errno != EEXIST) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 352 | gpr_asprintf( |
| 353 | &err_msg, |
| 354 | "epoll_ctl (epoll_fd: %d) add fd: %d failed with error: %d (%s)", |
| 355 | pi->epoll_fd, fds[i]->fd, errno, strerror(errno)); |
| 356 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 357 | gpr_free(err_msg); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 358 | } |
| 359 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 360 | continue; |
| 361 | } |
| 362 | |
| 363 | if (pi->fd_cnt == pi->fd_capacity) { |
| 364 | pi->fd_capacity = GPR_MAX(pi->fd_capacity + 8, pi->fd_cnt * 3 / 2); |
| 365 | pi->fds = gpr_realloc(pi->fds, sizeof(grpc_fd *) * pi->fd_capacity); |
| 366 | } |
| 367 | |
| 368 | pi->fds[pi->fd_cnt++] = fds[i]; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 369 | if (add_fd_refs) { |
| 370 | GRPC_FD_REF(fds[i], "polling_island"); |
| 371 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 372 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 373 | } |
| 374 | |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 375 | /* The caller is expected to hold pi->mu before calling this */ |
| 376 | static void polling_island_add_wakeup_fd_locked(polling_island *pi, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 377 | grpc_wakeup_fd *wakeup_fd, |
| 378 | grpc_error **error) { |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 379 | struct epoll_event ev; |
| 380 | int err; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 381 | char *err_msg; |
| 382 | const char *err_desc = "polling_island_add_wakeup_fd"; |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 383 | |
| 384 | ev.events = (uint32_t)(EPOLLIN | EPOLLET); |
| 385 | ev.data.ptr = wakeup_fd; |
| 386 | err = epoll_ctl(pi->epoll_fd, EPOLL_CTL_ADD, |
| 387 | GRPC_WAKEUP_FD_GET_READ_FD(wakeup_fd), &ev); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 388 | if (err < 0 && errno != EEXIST) { |
| 389 | gpr_asprintf(&err_msg, |
| 390 | "epoll_ctl (epoll_fd: %d) add wakeup fd: %d failed with " |
| 391 | "error: %d (%s)", |
Craig Tiller | c357179 | 2017-05-02 12:33:38 -0700 | [diff] [blame] | 392 | pi->epoll_fd, GRPC_WAKEUP_FD_GET_READ_FD(wakeup_fd), errno, |
| 393 | strerror(errno)); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 394 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 395 | gpr_free(err_msg); |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 396 | } |
| 397 | } |
| 398 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 399 | /* The caller is expected to hold pi->mu lock before calling this function */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 400 | static void polling_island_remove_all_fds_locked(polling_island *pi, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 401 | bool remove_fd_refs, |
| 402 | grpc_error **error) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 403 | int err; |
| 404 | size_t i; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 405 | char *err_msg; |
| 406 | const char *err_desc = "polling_island_remove_fds"; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 407 | |
| 408 | for (i = 0; i < pi->fd_cnt; i++) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 409 | err = epoll_ctl(pi->epoll_fd, EPOLL_CTL_DEL, pi->fds[i]->fd, NULL); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 410 | if (err < 0 && errno != ENOENT) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 411 | gpr_asprintf(&err_msg, |
| 412 | "epoll_ctl (epoll_fd: %d) delete fds[%zu]: %d failed with " |
| 413 | "error: %d (%s)", |
| 414 | pi->epoll_fd, i, pi->fds[i]->fd, errno, strerror(errno)); |
| 415 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 416 | gpr_free(err_msg); |
Sree Kuchibhotla | ad162ba | 2016-06-06 16:23:37 -0700 | [diff] [blame] | 417 | } |
| 418 | |
| 419 | if (remove_fd_refs) { |
| 420 | GRPC_FD_UNREF(pi->fds[i], "polling_island"); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 421 | } |
| 422 | } |
| 423 | |
| 424 | pi->fd_cnt = 0; |
| 425 | } |
| 426 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 427 | /* The caller is expected to hold pi->mu lock before calling this function */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 428 | static void polling_island_remove_fd_locked(polling_island *pi, grpc_fd *fd, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 429 | bool is_fd_closed, |
| 430 | grpc_error **error) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 431 | int err; |
| 432 | size_t i; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 433 | char *err_msg; |
| 434 | const char *err_desc = "polling_island_remove_fd"; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 435 | |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 436 | /* If fd is already closed, then it would have been automatically been removed |
| 437 | from the epoll set */ |
| 438 | if (!is_fd_closed) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 439 | err = epoll_ctl(pi->epoll_fd, EPOLL_CTL_DEL, fd->fd, NULL); |
| 440 | if (err < 0 && errno != ENOENT) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 441 | gpr_asprintf( |
| 442 | &err_msg, |
| 443 | "epoll_ctl (epoll_fd: %d) del fd: %d failed with error: %d (%s)", |
| 444 | pi->epoll_fd, fd->fd, errno, strerror(errno)); |
| 445 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 446 | gpr_free(err_msg); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 447 | } |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 448 | } |
| 449 | |
| 450 | for (i = 0; i < pi->fd_cnt; i++) { |
| 451 | if (pi->fds[i] == fd) { |
| 452 | pi->fds[i] = pi->fds[--pi->fd_cnt]; |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 453 | GRPC_FD_UNREF(fd, "polling_island"); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 454 | break; |
| 455 | } |
| 456 | } |
| 457 | } |
| 458 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 459 | /* Might return NULL in case of an error */ |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 460 | static polling_island *polling_island_create(grpc_exec_ctx *exec_ctx, |
| 461 | grpc_fd *initial_fd, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 462 | grpc_error **error) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 463 | polling_island *pi = NULL; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 464 | const char *err_desc = "polling_island_create"; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 465 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 466 | *error = GRPC_ERROR_NONE; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 467 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 468 | pi = gpr_malloc(sizeof(*pi)); |
| 469 | gpr_mu_init(&pi->mu); |
| 470 | pi->fd_cnt = 0; |
| 471 | pi->fd_capacity = 0; |
| 472 | pi->fds = NULL; |
| 473 | pi->epoll_fd = -1; |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 474 | |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 475 | gpr_atm_rel_store(&pi->ref_count, 0); |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 476 | gpr_atm_rel_store(&pi->poller_count, 0); |
Sree Kuchibhotla | 0224dcc | 2016-06-22 18:04:00 -0700 | [diff] [blame] | 477 | gpr_atm_rel_store(&pi->merged_to, (gpr_atm)NULL); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 478 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 479 | pi->epoll_fd = epoll_create1(EPOLL_CLOEXEC); |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 480 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 481 | if (pi->epoll_fd < 0) { |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 482 | append_error(error, GRPC_OS_ERROR(errno, "epoll_create1"), err_desc); |
| 483 | goto done; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 484 | } |
| 485 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 486 | if (initial_fd != NULL) { |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 487 | polling_island_add_fds_locked(pi, &initial_fd, 1, true, error); |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 488 | } |
| 489 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 490 | done: |
| 491 | if (*error != GRPC_ERROR_NONE) { |
Craig Tiller | 0a06cd7 | 2016-07-14 13:21:24 -0700 | [diff] [blame] | 492 | polling_island_delete(exec_ctx, pi); |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 493 | pi = NULL; |
| 494 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 495 | return pi; |
| 496 | } |
| 497 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 498 | static void polling_island_delete(grpc_exec_ctx *exec_ctx, polling_island *pi) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 499 | GPR_ASSERT(pi->fd_cnt == 0); |
| 500 | |
Craig Tiller | 0a06cd7 | 2016-07-14 13:21:24 -0700 | [diff] [blame] | 501 | if (pi->epoll_fd >= 0) { |
| 502 | close(pi->epoll_fd); |
| 503 | } |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 504 | gpr_mu_destroy(&pi->mu); |
| 505 | gpr_free(pi->fds); |
| 506 | gpr_free(pi); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 507 | } |
| 508 | |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 509 | /* Attempts to gets the last polling island in the linked list (liked by the |
| 510 | * 'merged_to' field). Since this does not lock the polling island, there are no |
| 511 | * guarantees that the island returned is the last island */ |
| 512 | static polling_island *polling_island_maybe_get_latest(polling_island *pi) { |
| 513 | polling_island *next = (polling_island *)gpr_atm_acq_load(&pi->merged_to); |
| 514 | while (next != NULL) { |
| 515 | pi = next; |
| 516 | next = (polling_island *)gpr_atm_acq_load(&pi->merged_to); |
| 517 | } |
| 518 | |
| 519 | return pi; |
| 520 | } |
| 521 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 522 | /* Gets the lock on the *latest* polling island i.e the last polling island in |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 523 | the linked list (linked by the 'merged_to' field). Call gpr_mu_unlock on the |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 524 | returned polling island's mu. |
| 525 | Usage: To lock/unlock polling island "pi", do the following: |
| 526 | polling_island *pi_latest = polling_island_lock(pi); |
| 527 | ... |
| 528 | ... critical section .. |
| 529 | ... |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 530 | gpr_mu_unlock(&pi_latest->mu); // NOTE: use pi_latest->mu. NOT pi->mu */ |
| 531 | static polling_island *polling_island_lock(polling_island *pi) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 532 | polling_island *next = NULL; |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 533 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 534 | while (true) { |
| 535 | next = (polling_island *)gpr_atm_acq_load(&pi->merged_to); |
| 536 | if (next == NULL) { |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 537 | /* Looks like 'pi' is the last node in the linked list but unless we check |
| 538 | this by holding the pi->mu lock, we cannot be sure (i.e without the |
| 539 | pi->mu lock, we don't prevent island merges). |
| 540 | To be absolutely sure, check once more by holding the pi->mu lock */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 541 | gpr_mu_lock(&pi->mu); |
| 542 | next = (polling_island *)gpr_atm_acq_load(&pi->merged_to); |
| 543 | if (next == NULL) { |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 544 | /* pi is infact the last node and we have the pi->mu lock. we're done */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 545 | break; |
| 546 | } |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 547 | |
| 548 | /* pi->merged_to is not NULL i.e pi isn't the last node anymore. pi->mu |
| 549 | * isn't the lock we are interested in. Continue traversing the list */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 550 | gpr_mu_unlock(&pi->mu); |
| 551 | } |
| 552 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 553 | pi = next; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 554 | } |
| 555 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 556 | return pi; |
| 557 | } |
| 558 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 559 | /* Gets the lock on the *latest* polling islands in the linked lists pointed by |
| 560 | *p and *q (and also updates *p and *q to point to the latest polling islands) |
| 561 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 562 | This function is needed because calling the following block of code to obtain |
| 563 | locks on polling islands (*p and *q) is prone to deadlocks. |
| 564 | { |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 565 | polling_island_lock(*p, true); |
| 566 | polling_island_lock(*q, true); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 567 | } |
| 568 | |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 569 | Usage/example: |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 570 | polling_island *p1; |
| 571 | polling_island *p2; |
| 572 | .. |
| 573 | polling_island_lock_pair(&p1, &p2); |
| 574 | .. |
| 575 | .. Critical section with both p1 and p2 locked |
| 576 | .. |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 577 | // Release locks: Always call polling_island_unlock_pair() to release locks |
| 578 | polling_island_unlock_pair(p1, p2); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 579 | */ |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 580 | static void polling_island_lock_pair(polling_island **p, polling_island **q) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 581 | polling_island *pi_1 = *p; |
| 582 | polling_island *pi_2 = *q; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 583 | polling_island *next_1 = NULL; |
| 584 | polling_island *next_2 = NULL; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 585 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 586 | /* The algorithm is simple: |
| 587 | - Go to the last polling islands in the linked lists *pi_1 and *pi_2 (and |
| 588 | keep updating pi_1 and pi_2) |
| 589 | - Then obtain locks on the islands by following a lock order rule of |
| 590 | locking polling_island with lower address first |
| 591 | Special case: Before obtaining the locks, check if pi_1 and pi_2 are |
| 592 | pointing to the same island. If that is the case, we can just call |
| 593 | polling_island_lock() |
| 594 | - After obtaining both the locks, double check that the polling islands |
| 595 | are still the last polling islands in their respective linked lists |
| 596 | (this is because there might have been polling island merges before |
| 597 | we got the lock) |
| 598 | - If the polling islands are the last islands, we are done. If not, |
| 599 | release the locks and continue the process from the first step */ |
| 600 | while (true) { |
| 601 | next_1 = (polling_island *)gpr_atm_acq_load(&pi_1->merged_to); |
| 602 | while (next_1 != NULL) { |
| 603 | pi_1 = next_1; |
| 604 | next_1 = (polling_island *)gpr_atm_acq_load(&pi_1->merged_to); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 605 | } |
| 606 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 607 | next_2 = (polling_island *)gpr_atm_acq_load(&pi_2->merged_to); |
| 608 | while (next_2 != NULL) { |
| 609 | pi_2 = next_2; |
| 610 | next_2 = (polling_island *)gpr_atm_acq_load(&pi_2->merged_to); |
| 611 | } |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 612 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 613 | if (pi_1 == pi_2) { |
| 614 | pi_1 = pi_2 = polling_island_lock(pi_1); |
| 615 | break; |
| 616 | } |
| 617 | |
| 618 | if (pi_1 < pi_2) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 619 | gpr_mu_lock(&pi_1->mu); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 620 | gpr_mu_lock(&pi_2->mu); |
| 621 | } else { |
| 622 | gpr_mu_lock(&pi_2->mu); |
| 623 | gpr_mu_lock(&pi_1->mu); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 624 | } |
| 625 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 626 | next_1 = (polling_island *)gpr_atm_acq_load(&pi_1->merged_to); |
| 627 | next_2 = (polling_island *)gpr_atm_acq_load(&pi_2->merged_to); |
| 628 | if (next_1 == NULL && next_2 == NULL) { |
| 629 | break; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 630 | } |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 631 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 632 | gpr_mu_unlock(&pi_1->mu); |
| 633 | gpr_mu_unlock(&pi_2->mu); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 634 | } |
| 635 | |
| 636 | *p = pi_1; |
| 637 | *q = pi_2; |
| 638 | } |
| 639 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 640 | static void polling_island_unlock_pair(polling_island *p, polling_island *q) { |
| 641 | if (p == q) { |
| 642 | gpr_mu_unlock(&p->mu); |
| 643 | } else { |
| 644 | gpr_mu_unlock(&p->mu); |
| 645 | gpr_mu_unlock(&q->mu); |
| 646 | } |
| 647 | } |
| 648 | |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 649 | static polling_island *polling_island_merge(polling_island *p, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 650 | polling_island *q, |
| 651 | grpc_error **error) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 652 | /* Get locks on both the polling islands */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 653 | polling_island_lock_pair(&p, &q); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 654 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 655 | if (p != q) { |
| 656 | /* Make sure that p points to the polling island with fewer fds than q */ |
| 657 | if (p->fd_cnt > q->fd_cnt) { |
| 658 | GPR_SWAP(polling_island *, p, q); |
| 659 | } |
| 660 | |
| 661 | /* Merge p with q i.e move all the fds from p (The one with fewer fds) to q |
| 662 | Note that the refcounts on the fds being moved will not change here. |
| 663 | This is why the last param in the following two functions is 'false') */ |
| 664 | polling_island_add_fds_locked(q, p->fds, p->fd_cnt, false, error); |
| 665 | polling_island_remove_all_fds_locked(p, false, error); |
| 666 | |
| 667 | /* Wakeup all the pollers (if any) on p so that they pickup this change */ |
| 668 | polling_island_add_wakeup_fd_locked(p, &polling_island_wakeup_fd, error); |
| 669 | |
| 670 | /* Add the 'merged_to' link from p --> q */ |
| 671 | gpr_atm_rel_store(&p->merged_to, (gpr_atm)q); |
| 672 | PI_ADD_REF(q, "pi_merge"); /* To account for the new incoming ref from p */ |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 673 | } |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 674 | /* else if p == q, nothing needs to be done */ |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 675 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 676 | polling_island_unlock_pair(p, q); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 677 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 678 | /* Return the merged polling island (Note that no merge would have happened |
| 679 | if p == q which is ok) */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 680 | return q; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 681 | } |
| 682 | |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 683 | static grpc_error *polling_island_global_init() { |
| 684 | grpc_error *error = GRPC_ERROR_NONE; |
| 685 | |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 686 | error = grpc_wakeup_fd_init(&polling_island_wakeup_fd); |
| 687 | if (error == GRPC_ERROR_NONE) { |
| 688 | error = grpc_wakeup_fd_wakeup(&polling_island_wakeup_fd); |
| 689 | } |
| 690 | |
| 691 | return error; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 692 | } |
| 693 | |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 694 | static void polling_island_global_shutdown() { |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 695 | grpc_wakeup_fd_destroy(&polling_island_wakeup_fd); |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 696 | } |
| 697 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 698 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 699 | * Fd Definitions |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 700 | */ |
| 701 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 702 | /* We need to keep a freelist not because of any concerns of malloc performance |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 703 | * but instead so that implementations with multiple threads in (for example) |
| 704 | * epoll_wait deal with the race between pollset removal and incoming poll |
| 705 | * notifications. |
| 706 | * |
| 707 | * The problem is that the poller ultimately holds a reference to this |
| 708 | * object, so it is very difficult to know when is safe to free it, at least |
| 709 | * without some expensive synchronization. |
| 710 | * |
| 711 | * If we keep the object freelisted, in the worst case losing this race just |
| 712 | * becomes a spurious read notification on a reused fd. |
| 713 | */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 714 | |
| 715 | /* The alarm system needs to be able to wakeup 'some poller' sometimes |
| 716 | * (specifically when a new alarm needs to be triggered earlier than the next |
| 717 | * alarm 'epoch'). This wakeup_fd gives us something to alert on when such a |
| 718 | * case occurs. */ |
Sree Kuchibhotla | 9bc3d2d | 2016-06-06 10:27:56 -0700 | [diff] [blame] | 719 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 720 | static grpc_fd *fd_freelist = NULL; |
| 721 | static gpr_mu fd_freelist_mu; |
| 722 | |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 723 | #ifndef NDEBUG |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 724 | #define REF_BY(fd, n, reason) ref_by(fd, n, reason, __FILE__, __LINE__) |
| 725 | #define UNREF_BY(fd, n, reason) unref_by(fd, n, reason, __FILE__, __LINE__) |
| 726 | static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file, |
| 727 | int line) { |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 728 | if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) { |
ncteisen | 973863d | 2017-06-12 10:28:50 -0700 | [diff] [blame] | 729 | gpr_log(GPR_DEBUG, |
| 730 | "FD %d %p ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]", |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 731 | fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst), |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 732 | gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line); |
| 733 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 734 | #else |
| 735 | #define REF_BY(fd, n, reason) ref_by(fd, n) |
| 736 | #define UNREF_BY(fd, n, reason) unref_by(fd, n) |
| 737 | static void ref_by(grpc_fd *fd, int n) { |
| 738 | #endif |
| 739 | GPR_ASSERT(gpr_atm_no_barrier_fetch_add(&fd->refst, n) > 0); |
| 740 | } |
| 741 | |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 742 | #ifndef NDEBUG |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 743 | static void unref_by(grpc_fd *fd, int n, const char *reason, const char *file, |
| 744 | int line) { |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 745 | if (GRPC_TRACER_ON(grpc_trace_fd_refcount)) { |
ncteisen | 973863d | 2017-06-12 10:28:50 -0700 | [diff] [blame] | 746 | gpr_log(GPR_DEBUG, |
| 747 | "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]", |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 748 | fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst), |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 749 | gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line); |
| 750 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 751 | #else |
| 752 | static void unref_by(grpc_fd *fd, int n) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 753 | #endif |
Noah Eisen | 264879f | 2017-06-20 17:14:47 -0700 | [diff] [blame] | 754 | gpr_atm old = gpr_atm_full_fetch_add(&fd->refst, -n); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 755 | if (old == n) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 756 | /* Add the fd to the freelist */ |
| 757 | gpr_mu_lock(&fd_freelist_mu); |
| 758 | fd->freelist_next = fd_freelist; |
| 759 | fd_freelist = fd; |
| 760 | grpc_iomgr_unregister_object(&fd->iomgr_object); |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 761 | |
Craig Tiller | 376887d | 2017-04-06 08:27:03 -0700 | [diff] [blame] | 762 | grpc_lfev_destroy(&fd->read_closure); |
| 763 | grpc_lfev_destroy(&fd->write_closure); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 764 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 765 | gpr_mu_unlock(&fd_freelist_mu); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 766 | } else { |
| 767 | GPR_ASSERT(old > n); |
| 768 | } |
| 769 | } |
| 770 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 771 | /* Increment refcount by two to avoid changing the orphan bit */ |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 772 | #ifndef NDEBUG |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 773 | static void fd_ref(grpc_fd *fd, const char *reason, const char *file, |
| 774 | int line) { |
| 775 | ref_by(fd, 2, reason, file, line); |
| 776 | } |
| 777 | |
| 778 | static void fd_unref(grpc_fd *fd, const char *reason, const char *file, |
| 779 | int line) { |
| 780 | unref_by(fd, 2, reason, file, line); |
| 781 | } |
| 782 | #else |
| 783 | static void fd_ref(grpc_fd *fd) { ref_by(fd, 2); } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 784 | static void fd_unref(grpc_fd *fd) { unref_by(fd, 2); } |
| 785 | #endif |
| 786 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 787 | static void fd_global_init(void) { gpr_mu_init(&fd_freelist_mu); } |
| 788 | |
| 789 | static void fd_global_shutdown(void) { |
| 790 | gpr_mu_lock(&fd_freelist_mu); |
| 791 | gpr_mu_unlock(&fd_freelist_mu); |
| 792 | while (fd_freelist != NULL) { |
| 793 | grpc_fd *fd = fd_freelist; |
| 794 | fd_freelist = fd_freelist->freelist_next; |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 795 | gpr_mu_destroy(&fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 796 | gpr_free(fd); |
| 797 | } |
| 798 | gpr_mu_destroy(&fd_freelist_mu); |
| 799 | } |
| 800 | |
| 801 | static grpc_fd *fd_create(int fd, const char *name) { |
| 802 | grpc_fd *new_fd = NULL; |
| 803 | |
| 804 | gpr_mu_lock(&fd_freelist_mu); |
| 805 | if (fd_freelist != NULL) { |
| 806 | new_fd = fd_freelist; |
| 807 | fd_freelist = fd_freelist->freelist_next; |
| 808 | } |
| 809 | gpr_mu_unlock(&fd_freelist_mu); |
| 810 | |
| 811 | if (new_fd == NULL) { |
| 812 | new_fd = gpr_malloc(sizeof(grpc_fd)); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 813 | gpr_mu_init(&new_fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 814 | } |
| 815 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 816 | /* Note: It is not really needed to get the new_fd->po.mu lock here. If this |
| 817 | * is a newly created fd (or an fd we got from the freelist), no one else |
| 818 | * would be holding a lock to it anyway. */ |
| 819 | gpr_mu_lock(&new_fd->po.mu); |
| 820 | new_fd->po.pi = NULL; |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame^] | 821 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 822 | new_fd->po.obj_type = POLL_OBJ_FD; |
| 823 | #endif |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 824 | |
Sree Kuchibhotla | 0224dcc | 2016-06-22 18:04:00 -0700 | [diff] [blame] | 825 | gpr_atm_rel_store(&new_fd->refst, (gpr_atm)1); |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 826 | new_fd->fd = fd; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 827 | new_fd->orphaned = false; |
Craig Tiller | 376887d | 2017-04-06 08:27:03 -0700 | [diff] [blame] | 828 | grpc_lfev_init(&new_fd->read_closure); |
| 829 | grpc_lfev_init(&new_fd->write_closure); |
Sree Kuchibhotla | 61fe094 | 2017-02-14 12:26:56 -0800 | [diff] [blame] | 830 | gpr_atm_no_barrier_store(&new_fd->read_notifier_pollset, (gpr_atm)NULL); |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 831 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 832 | new_fd->freelist_next = NULL; |
| 833 | new_fd->on_done_closure = NULL; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 834 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 835 | gpr_mu_unlock(&new_fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 836 | |
| 837 | char *fd_name; |
| 838 | gpr_asprintf(&fd_name, "%s fd=%d", name, fd); |
| 839 | grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name); |
Sree Kuchibhotla | 6a29545 | 2016-06-23 15:53:10 -0700 | [diff] [blame] | 840 | gpr_free(fd_name); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 841 | return new_fd; |
| 842 | } |
| 843 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 844 | static int fd_wrapped_fd(grpc_fd *fd) { |
| 845 | int ret_fd = -1; |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 846 | gpr_mu_lock(&fd->po.mu); |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 847 | if (!fd->orphaned) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 848 | ret_fd = fd->fd; |
| 849 | } |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 850 | gpr_mu_unlock(&fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 851 | |
| 852 | return ret_fd; |
| 853 | } |
| 854 | |
| 855 | static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 856 | grpc_closure *on_done, int *release_fd, |
| 857 | const char *reason) { |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 858 | bool is_fd_closed = false; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 859 | grpc_error *error = GRPC_ERROR_NONE; |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 860 | polling_island *unref_pi = NULL; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 861 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 862 | gpr_mu_lock(&fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 863 | fd->on_done_closure = on_done; |
| 864 | |
| 865 | /* If release_fd is not NULL, we should be relinquishing control of the file |
| 866 | descriptor fd->fd (but we still own the grpc_fd structure). */ |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 867 | if (release_fd != NULL) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 868 | *release_fd = fd->fd; |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 869 | } else { |
| 870 | close(fd->fd); |
| 871 | is_fd_closed = true; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 872 | } |
| 873 | |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 874 | fd->orphaned = true; |
| 875 | |
| 876 | /* Remove the active status but keep referenced. We want this grpc_fd struct |
| 877 | to be alive (and not added to freelist) until the end of this function */ |
| 878 | REF_BY(fd, 1, reason); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 879 | |
| 880 | /* Remove the fd from the polling island: |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 881 | - Get a lock on the latest polling island (i.e the last island in the |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 882 | linked list pointed by fd->po.pi). This is the island that |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 883 | would actually contain the fd |
| 884 | - Remove the fd from the latest polling island |
| 885 | - Unlock the latest polling island |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 886 | - Set fd->po.pi to NULL (but remove the ref on the polling island |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 887 | before doing this.) */ |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 888 | if (fd->po.pi != NULL) { |
| 889 | polling_island *pi_latest = polling_island_lock(fd->po.pi); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 890 | polling_island_remove_fd_locked(pi_latest, fd, is_fd_closed, &error); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 891 | gpr_mu_unlock(&pi_latest->mu); |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 892 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 893 | unref_pi = fd->po.pi; |
| 894 | fd->po.pi = NULL; |
Sree Kuchibhotla | 88ee12f | 2016-06-03 19:26:48 -0700 | [diff] [blame] | 895 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 896 | |
ncteisen | 969b46e | 2017-06-08 14:57:11 -0700 | [diff] [blame] | 897 | GRPC_CLOSURE_SCHED(exec_ctx, fd->on_done_closure, GRPC_ERROR_REF(error)); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 898 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 899 | gpr_mu_unlock(&fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 900 | UNREF_BY(fd, 2, reason); /* Drop the reference */ |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 901 | if (unref_pi != NULL) { |
Craig Tiller | 0a06cd7 | 2016-07-14 13:21:24 -0700 | [diff] [blame] | 902 | /* Unref stale polling island here, outside the fd lock above. |
| 903 | The polling island owns a workqueue which owns an fd, and unreffing |
| 904 | inside the lock can cause an eventual lock loop that makes TSAN very |
| 905 | unhappy. */ |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 906 | PI_UNREF(exec_ctx, unref_pi, "fd_orphan"); |
| 907 | } |
Yuchen Zeng | 4ebace7 | 2017-06-05 17:24:06 -0700 | [diff] [blame] | 908 | if (error != GRPC_ERROR_NONE) { |
| 909 | const char *msg = grpc_error_string(error); |
| 910 | gpr_log(GPR_DEBUG, "fd_orphan: %s", msg); |
| 911 | } |
Yuchen Zeng | a0399f2 | 2016-08-04 17:52:53 -0700 | [diff] [blame] | 912 | GRPC_ERROR_UNREF(error); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 913 | } |
| 914 | |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 915 | static grpc_pollset *fd_get_read_notifier_pollset(grpc_exec_ctx *exec_ctx, |
| 916 | grpc_fd *fd) { |
Sree Kuchibhotla | fb7ced6 | 2017-02-15 18:31:57 -0800 | [diff] [blame] | 917 | gpr_atm notifier = gpr_atm_acq_load(&fd->read_notifier_pollset); |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 918 | return (grpc_pollset *)notifier; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 919 | } |
| 920 | |
Sree Kuchibhotla | 24b6eae | 2016-06-21 18:01:14 -0700 | [diff] [blame] | 921 | static bool fd_is_shutdown(grpc_fd *fd) { |
Craig Tiller | 376887d | 2017-04-06 08:27:03 -0700 | [diff] [blame] | 922 | return grpc_lfev_is_shutdown(&fd->read_closure); |
Sree Kuchibhotla | 24b6eae | 2016-06-21 18:01:14 -0700 | [diff] [blame] | 923 | } |
| 924 | |
Sree Kuchibhotla | 0100b2f | 2016-06-21 17:38:13 -0700 | [diff] [blame] | 925 | /* Might be called multiple times */ |
Craig Tiller | cda759d | 2017-01-27 11:37:37 -0800 | [diff] [blame] | 926 | static void fd_shutdown(grpc_exec_ctx *exec_ctx, grpc_fd *fd, grpc_error *why) { |
Craig Tiller | e16372b | 2017-04-06 08:51:39 -0700 | [diff] [blame] | 927 | if (grpc_lfev_set_shutdown(exec_ctx, &fd->read_closure, |
| 928 | GRPC_ERROR_REF(why))) { |
Sree Kuchibhotla | 0100b2f | 2016-06-21 17:38:13 -0700 | [diff] [blame] | 929 | shutdown(fd->fd, SHUT_RDWR); |
Craig Tiller | e16372b | 2017-04-06 08:51:39 -0700 | [diff] [blame] | 930 | grpc_lfev_set_shutdown(exec_ctx, &fd->write_closure, GRPC_ERROR_REF(why)); |
Sree Kuchibhotla | 0100b2f | 2016-06-21 17:38:13 -0700 | [diff] [blame] | 931 | } |
Craig Tiller | 376887d | 2017-04-06 08:27:03 -0700 | [diff] [blame] | 932 | GRPC_ERROR_UNREF(why); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 933 | } |
| 934 | |
| 935 | static void fd_notify_on_read(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 936 | grpc_closure *closure) { |
Craig Tiller | 7065214 | 2017-04-06 08:31:23 -0700 | [diff] [blame] | 937 | grpc_lfev_notify_on(exec_ctx, &fd->read_closure, closure); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 938 | } |
| 939 | |
| 940 | static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 941 | grpc_closure *closure) { |
Craig Tiller | 7065214 | 2017-04-06 08:31:23 -0700 | [diff] [blame] | 942 | grpc_lfev_notify_on(exec_ctx, &fd->write_closure, closure); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 943 | } |
| 944 | |
| 945 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 946 | * Pollset Definitions |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 947 | */ |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 948 | GPR_TLS_DECL(g_current_thread_pollset); |
| 949 | GPR_TLS_DECL(g_current_thread_worker); |
Craig Tiller | 1919699 | 2016-06-27 18:45:56 -0700 | [diff] [blame] | 950 | static __thread bool g_initialized_sigmask; |
| 951 | static __thread sigset_t g_orig_sigmask; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 952 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 953 | static void sig_handler(int sig_num) { |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 954 | #ifdef GRPC_EPOLL_DEBUG |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 955 | gpr_log(GPR_INFO, "Received signal %d", sig_num); |
Sree Kuchibhotla | 9bc3d2d | 2016-06-06 10:27:56 -0700 | [diff] [blame] | 956 | #endif |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 957 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 958 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 959 | static void poller_kick_init() { signal(grpc_wakeup_signal, sig_handler); } |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 960 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 961 | /* Global state management */ |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 962 | static grpc_error *pollset_global_init(void) { |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 963 | gpr_tls_init(&g_current_thread_pollset); |
| 964 | gpr_tls_init(&g_current_thread_worker); |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 965 | poller_kick_init(); |
Craig Tiller | c357179 | 2017-05-02 12:33:38 -0700 | [diff] [blame] | 966 | return GRPC_ERROR_NONE; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 967 | } |
| 968 | |
| 969 | static void pollset_global_shutdown(void) { |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 970 | gpr_tls_destroy(&g_current_thread_pollset); |
| 971 | gpr_tls_destroy(&g_current_thread_worker); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 972 | } |
| 973 | |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 974 | static grpc_error *pollset_worker_kick(grpc_pollset_worker *worker) { |
| 975 | grpc_error *err = GRPC_ERROR_NONE; |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 976 | |
| 977 | /* Kick the worker only if it was not already kicked */ |
| 978 | if (gpr_atm_no_barrier_cas(&worker->is_kicked, (gpr_atm)0, (gpr_atm)1)) { |
| 979 | GRPC_POLLING_TRACE( |
| 980 | "pollset_worker_kick: Kicking worker: %p (thread id: %ld)", |
Ken Payson | 975b510 | 2017-03-30 17:38:40 -0700 | [diff] [blame] | 981 | (void *)worker, (long int)worker->pt_id); |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 982 | int err_num = pthread_kill(worker->pt_id, grpc_wakeup_signal); |
| 983 | if (err_num != 0) { |
| 984 | err = GRPC_OS_ERROR(err_num, "pthread_kill"); |
| 985 | } |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 986 | } |
| 987 | return err; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 988 | } |
| 989 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 990 | /* Return 1 if the pollset has active threads in pollset_work (pollset must |
| 991 | * be locked) */ |
| 992 | static int pollset_has_workers(grpc_pollset *p) { |
| 993 | return p->root_worker.next != &p->root_worker; |
| 994 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 995 | |
| 996 | static void remove_worker(grpc_pollset *p, grpc_pollset_worker *worker) { |
| 997 | worker->prev->next = worker->next; |
| 998 | worker->next->prev = worker->prev; |
| 999 | } |
| 1000 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1001 | static grpc_pollset_worker *pop_front_worker(grpc_pollset *p) { |
| 1002 | if (pollset_has_workers(p)) { |
| 1003 | grpc_pollset_worker *w = p->root_worker.next; |
| 1004 | remove_worker(p, w); |
| 1005 | return w; |
| 1006 | } else { |
| 1007 | return NULL; |
| 1008 | } |
| 1009 | } |
| 1010 | |
| 1011 | static void push_back_worker(grpc_pollset *p, grpc_pollset_worker *worker) { |
| 1012 | worker->next = &p->root_worker; |
| 1013 | worker->prev = worker->next->prev; |
| 1014 | worker->prev->next = worker->next->prev = worker; |
| 1015 | } |
| 1016 | |
| 1017 | static void push_front_worker(grpc_pollset *p, grpc_pollset_worker *worker) { |
| 1018 | worker->prev = &p->root_worker; |
| 1019 | worker->next = worker->prev->next; |
| 1020 | worker->prev->next = worker->next->prev = worker; |
| 1021 | } |
| 1022 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1023 | /* p->mu must be held before calling this function */ |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1024 | static grpc_error *pollset_kick(grpc_pollset *p, |
| 1025 | grpc_pollset_worker *specific_worker) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1026 | GPR_TIMER_BEGIN("pollset_kick", 0); |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1027 | grpc_error *error = GRPC_ERROR_NONE; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1028 | const char *err_desc = "Kick Failure"; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1029 | grpc_pollset_worker *worker = specific_worker; |
| 1030 | if (worker != NULL) { |
| 1031 | if (worker == GRPC_POLLSET_KICK_BROADCAST) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1032 | if (pollset_has_workers(p)) { |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 1033 | GPR_TIMER_BEGIN("pollset_kick.broadcast", 0); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1034 | for (worker = p->root_worker.next; worker != &p->root_worker; |
| 1035 | worker = worker->next) { |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1036 | if (gpr_tls_get(&g_current_thread_worker) != (intptr_t)worker) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1037 | append_error(&error, pollset_worker_kick(worker), err_desc); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1038 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1039 | } |
Craig Tiller | a218a06 | 2016-06-26 09:58:37 -0700 | [diff] [blame] | 1040 | GPR_TIMER_END("pollset_kick.broadcast", 0); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1041 | } else { |
| 1042 | p->kicked_without_pollers = true; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1043 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1044 | } else { |
| 1045 | GPR_TIMER_MARK("kicked_specifically", 0); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1046 | if (gpr_tls_get(&g_current_thread_worker) != (intptr_t)worker) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1047 | append_error(&error, pollset_worker_kick(worker), err_desc); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1048 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1049 | } |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1050 | } else if (gpr_tls_get(&g_current_thread_pollset) != (intptr_t)p) { |
| 1051 | /* Since worker == NULL, it means that we can kick "any" worker on this |
| 1052 | pollset 'p'. If 'p' happens to be the same pollset this thread is |
| 1053 | currently polling (i.e in pollset_work() function), then there is no need |
| 1054 | to kick any other worker since the current thread can just absorb the |
| 1055 | kick. This is the reason why we enter this case only when |
| 1056 | g_current_thread_pollset is != p */ |
| 1057 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1058 | GPR_TIMER_MARK("kick_anonymous", 0); |
| 1059 | worker = pop_front_worker(p); |
| 1060 | if (worker != NULL) { |
| 1061 | GPR_TIMER_MARK("finally_kick", 0); |
| 1062 | push_back_worker(p, worker); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1063 | append_error(&error, pollset_worker_kick(worker), err_desc); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1064 | } else { |
| 1065 | GPR_TIMER_MARK("kicked_no_pollers", 0); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1066 | p->kicked_without_pollers = true; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1067 | } |
| 1068 | } |
| 1069 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1070 | GPR_TIMER_END("pollset_kick", 0); |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1071 | GRPC_LOG_IF_ERROR("pollset_kick", GRPC_ERROR_REF(error)); |
| 1072 | return error; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1073 | } |
| 1074 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1075 | static void pollset_init(grpc_pollset *pollset, gpr_mu **mu) { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1076 | gpr_mu_init(&pollset->po.mu); |
| 1077 | *mu = &pollset->po.mu; |
| 1078 | pollset->po.pi = NULL; |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame^] | 1079 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1080 | pollset->po.obj_type = POLL_OBJ_POLLSET; |
| 1081 | #endif |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1082 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1083 | pollset->root_worker.next = pollset->root_worker.prev = &pollset->root_worker; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1084 | pollset->kicked_without_pollers = false; |
| 1085 | |
| 1086 | pollset->shutting_down = false; |
| 1087 | pollset->finish_shutdown_called = false; |
| 1088 | pollset->shutdown_done = NULL; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1089 | } |
| 1090 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1091 | /* Convert a timespec to milliseconds: |
| 1092 | - Very small or negative poll times are clamped to zero to do a non-blocking |
| 1093 | poll (which becomes spin polling) |
| 1094 | - Other small values are rounded up to one millisecond |
| 1095 | - Longer than a millisecond polls are rounded up to the next nearest |
| 1096 | millisecond to avoid spinning |
| 1097 | - Infinite timeouts are converted to -1 */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1098 | static int poll_deadline_to_millis_timeout(gpr_timespec deadline, |
| 1099 | gpr_timespec now) { |
| 1100 | gpr_timespec timeout; |
| 1101 | static const int64_t max_spin_polling_us = 10; |
| 1102 | if (gpr_time_cmp(deadline, gpr_inf_future(deadline.clock_type)) == 0) { |
| 1103 | return -1; |
| 1104 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1105 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1106 | if (gpr_time_cmp(deadline, gpr_time_add(now, gpr_time_from_micros( |
| 1107 | max_spin_polling_us, |
| 1108 | GPR_TIMESPAN))) <= 0) { |
| 1109 | return 0; |
| 1110 | } |
| 1111 | timeout = gpr_time_sub(deadline, now); |
Craig Tiller | 799e7e8 | 2017-03-27 12:42:34 -0700 | [diff] [blame] | 1112 | int millis = gpr_time_to_millis(gpr_time_add( |
| 1113 | timeout, gpr_time_from_nanos(GPR_NS_PER_MS - 1, GPR_TIMESPAN))); |
| 1114 | return millis >= 1 ? millis : 1; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1115 | } |
| 1116 | |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 1117 | static void fd_become_readable(grpc_exec_ctx *exec_ctx, grpc_fd *fd, |
| 1118 | grpc_pollset *notifier) { |
Craig Tiller | 7065214 | 2017-04-06 08:31:23 -0700 | [diff] [blame] | 1119 | grpc_lfev_set_ready(exec_ctx, &fd->read_closure); |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 1120 | |
Sree Kuchibhotla | 4db8c82 | 2017-02-12 17:07:31 -0800 | [diff] [blame] | 1121 | /* Note, it is possible that fd_become_readable might be called twice with |
Sree Kuchibhotla | 4c60d0d | 2017-02-12 17:09:08 -0800 | [diff] [blame] | 1122 | different 'notifier's when an fd becomes readable and it is in two epoll |
| 1123 | sets (This can happen briefly during polling island merges). In such cases |
| 1124 | it does not really matter which notifer is set as the read_notifier_pollset |
| 1125 | (They would both point to the same polling island anyway) */ |
Sree Kuchibhotla | fb7ced6 | 2017-02-15 18:31:57 -0800 | [diff] [blame] | 1126 | /* Use release store to match with acquire load in fd_get_read_notifier */ |
| 1127 | gpr_atm_rel_store(&fd->read_notifier_pollset, (gpr_atm)notifier); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1128 | } |
| 1129 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1130 | static void fd_become_writable(grpc_exec_ctx *exec_ctx, grpc_fd *fd) { |
Craig Tiller | e16372b | 2017-04-06 08:51:39 -0700 | [diff] [blame] | 1131 | grpc_lfev_set_ready(exec_ctx, &fd->write_closure); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1132 | } |
| 1133 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 1134 | static void pollset_release_polling_island(grpc_exec_ctx *exec_ctx, |
| 1135 | grpc_pollset *ps, char *reason) { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1136 | if (ps->po.pi != NULL) { |
| 1137 | PI_UNREF(exec_ctx, ps->po.pi, reason); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1138 | } |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1139 | ps->po.pi = NULL; |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1140 | } |
| 1141 | |
| 1142 | static void finish_shutdown_locked(grpc_exec_ctx *exec_ctx, |
| 1143 | grpc_pollset *pollset) { |
| 1144 | /* The pollset cannot have any workers if we are at this stage */ |
| 1145 | GPR_ASSERT(!pollset_has_workers(pollset)); |
| 1146 | |
| 1147 | pollset->finish_shutdown_called = true; |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1148 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1149 | /* Release the ref and set pollset->po.pi to NULL */ |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 1150 | pollset_release_polling_island(exec_ctx, pollset, "ps_shutdown"); |
ncteisen | 969b46e | 2017-06-08 14:57:11 -0700 | [diff] [blame] | 1151 | GRPC_CLOSURE_SCHED(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1152 | } |
| 1153 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1154 | /* pollset->po.mu lock must be held by the caller before calling this */ |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1155 | static void pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, |
| 1156 | grpc_closure *closure) { |
| 1157 | GPR_TIMER_BEGIN("pollset_shutdown", 0); |
| 1158 | GPR_ASSERT(!pollset->shutting_down); |
| 1159 | pollset->shutting_down = true; |
| 1160 | pollset->shutdown_done = closure; |
| 1161 | pollset_kick(pollset, GRPC_POLLSET_KICK_BROADCAST); |
| 1162 | |
| 1163 | /* If the pollset has any workers, we cannot call finish_shutdown_locked() |
| 1164 | because it would release the underlying polling island. In such a case, we |
| 1165 | let the last worker call finish_shutdown_locked() from pollset_work() */ |
| 1166 | if (!pollset_has_workers(pollset)) { |
| 1167 | GPR_ASSERT(!pollset->finish_shutdown_called); |
| 1168 | GPR_TIMER_MARK("pollset_shutdown.finish_shutdown_locked", 0); |
| 1169 | finish_shutdown_locked(exec_ctx, pollset); |
| 1170 | } |
| 1171 | GPR_TIMER_END("pollset_shutdown", 0); |
| 1172 | } |
| 1173 | |
| 1174 | /* pollset_shutdown is guaranteed to be called before pollset_destroy. So other |
| 1175 | * than destroying the mutexes, there is nothing special that needs to be done |
| 1176 | * here */ |
Craig Tiller | f840110 | 2017-04-17 09:47:28 -0700 | [diff] [blame] | 1177 | static void pollset_destroy(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) { |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1178 | GPR_ASSERT(!pollset_has_workers(pollset)); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1179 | gpr_mu_destroy(&pollset->po.mu); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1180 | } |
| 1181 | |
Craig Tiller | 84ea341 | 2016-09-08 14:57:56 -0700 | [diff] [blame] | 1182 | #define GRPC_EPOLL_MAX_EVENTS 100 |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1183 | /* Note: sig_mask contains the signal mask to use *during* epoll_wait() */ |
| 1184 | static void pollset_work_and_unlock(grpc_exec_ctx *exec_ctx, |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1185 | grpc_pollset *pollset, |
| 1186 | grpc_pollset_worker *worker, int timeout_ms, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1187 | sigset_t *sig_mask, grpc_error **error) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1188 | struct epoll_event ep_ev[GRPC_EPOLL_MAX_EVENTS]; |
Sree Kuchibhotla | 88ee12f | 2016-06-03 19:26:48 -0700 | [diff] [blame] | 1189 | int epoll_fd = -1; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1190 | int ep_rv; |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 1191 | polling_island *pi = NULL; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1192 | char *err_msg; |
| 1193 | const char *err_desc = "pollset_work_and_unlock"; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1194 | GPR_TIMER_BEGIN("pollset_work_and_unlock", 0); |
| 1195 | |
| 1196 | /* We need to get the epoll_fd to wait on. The epoll_fd is in inside the |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1197 | latest polling island pointed by pollset->po.pi |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 1198 | |
| 1199 | Since epoll_fd is immutable, we can read it without obtaining the polling |
| 1200 | island lock. There is however a possibility that the polling island (from |
| 1201 | which we got the epoll_fd) got merged with another island while we are |
| 1202 | in this function. This is still okay because in such a case, we will wakeup |
| 1203 | right-away from epoll_wait() and pick up the latest polling_island the next |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1204 | this function (i.e pollset_work_and_unlock()) is called */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1205 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1206 | if (pollset->po.pi == NULL) { |
| 1207 | pollset->po.pi = polling_island_create(exec_ctx, NULL, error); |
| 1208 | if (pollset->po.pi == NULL) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1209 | GPR_TIMER_END("pollset_work_and_unlock", 0); |
| 1210 | return; /* Fatal error. We cannot continue */ |
| 1211 | } |
| 1212 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1213 | PI_ADD_REF(pollset->po.pi, "ps"); |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1214 | GRPC_POLLING_TRACE("pollset_work: pollset: %p created new pi: %p", |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1215 | (void *)pollset, (void *)pollset->po.pi); |
Sree Kuchibhotla | 88ee12f | 2016-06-03 19:26:48 -0700 | [diff] [blame] | 1216 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1217 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1218 | pi = polling_island_maybe_get_latest(pollset->po.pi); |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 1219 | epoll_fd = pi->epoll_fd; |
| 1220 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1221 | /* Update the pollset->po.pi since the island being pointed by |
| 1222 | pollset->po.pi maybe older than the one pointed by pi) */ |
| 1223 | if (pollset->po.pi != pi) { |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1224 | /* Always do PI_ADD_REF before PI_UNREF because PI_UNREF may cause the |
| 1225 | polling island to be deleted */ |
| 1226 | PI_ADD_REF(pi, "ps"); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1227 | PI_UNREF(exec_ctx, pollset->po.pi, "ps"); |
| 1228 | pollset->po.pi = pi; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1229 | } |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 1230 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1231 | /* Add an extra ref so that the island does not get destroyed (which means |
| 1232 | the epoll_fd won't be closed) while we are are doing an epoll_wait() on the |
| 1233 | epoll_fd */ |
| 1234 | PI_ADD_REF(pi, "ps_work"); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1235 | gpr_mu_unlock(&pollset->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1236 | |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1237 | gpr_atm_no_barrier_fetch_add(&pi->poller_count, 1); |
| 1238 | g_current_thread_polling_island = pi; |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 1239 | |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1240 | GRPC_SCHEDULING_START_BLOCKING_REGION; |
| 1241 | ep_rv = |
| 1242 | epoll_pwait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, timeout_ms, sig_mask); |
| 1243 | GRPC_SCHEDULING_END_BLOCKING_REGION; |
| 1244 | if (ep_rv < 0) { |
| 1245 | if (errno != EINTR) { |
| 1246 | gpr_asprintf(&err_msg, |
| 1247 | "epoll_wait() epoll fd: %d failed with error: %d (%s)", |
| 1248 | epoll_fd, errno, strerror(errno)); |
| 1249 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 1250 | } else { |
| 1251 | /* We were interrupted. Save an interation by doing a zero timeout |
| 1252 | epoll_wait to see if there are any other events of interest */ |
| 1253 | GRPC_POLLING_TRACE("pollset_work: pollset: %p, worker: %p received kick", |
| 1254 | (void *)pollset, (void *)worker); |
| 1255 | ep_rv = epoll_wait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, 0); |
Sree Kuchibhotla | e5012ba | 2016-06-06 16:01:45 -0700 | [diff] [blame] | 1256 | } |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1257 | } |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 1258 | |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 1259 | #ifdef GRPC_TSAN |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1260 | /* See the definition of g_poll_sync for more details */ |
| 1261 | gpr_atm_acq_load(&g_epoll_sync); |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 1262 | #endif /* defined(GRPC_TSAN) */ |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 1263 | |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1264 | for (int i = 0; i < ep_rv; ++i) { |
| 1265 | void *data_ptr = ep_ev[i].data.ptr; |
| 1266 | if (data_ptr == &polling_island_wakeup_fd) { |
| 1267 | GRPC_POLLING_TRACE( |
| 1268 | "pollset_work: pollset: %p, worker: %p polling island (epoll_fd: " |
| 1269 | "%d) got merged", |
| 1270 | (void *)pollset, (void *)worker, epoll_fd); |
| 1271 | /* This means that our polling island is merged with a different |
| 1272 | island. We do not have to do anything here since the subsequent call |
| 1273 | to the function pollset_work_and_unlock() will pick up the correct |
| 1274 | epoll_fd */ |
| 1275 | } else { |
| 1276 | grpc_fd *fd = data_ptr; |
| 1277 | int cancel = ep_ev[i].events & (EPOLLERR | EPOLLHUP); |
| 1278 | int read_ev = ep_ev[i].events & (EPOLLIN | EPOLLPRI); |
| 1279 | int write_ev = ep_ev[i].events & EPOLLOUT; |
| 1280 | if (read_ev || cancel) { |
| 1281 | fd_become_readable(exec_ctx, fd, pollset); |
| 1282 | } |
| 1283 | if (write_ev || cancel) { |
| 1284 | fd_become_writable(exec_ctx, fd); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1285 | } |
Sree Kuchibhotla | e5012ba | 2016-06-06 16:01:45 -0700 | [diff] [blame] | 1286 | } |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 1287 | } |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 1288 | |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1289 | g_current_thread_polling_island = NULL; |
| 1290 | gpr_atm_no_barrier_fetch_add(&pi->poller_count, -1); |
| 1291 | |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 1292 | GPR_ASSERT(pi != NULL); |
| 1293 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1294 | /* Before leaving, release the extra ref we added to the polling island. It |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1295 | is important to use "pi" here (i.e our old copy of pollset->po.pi |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1296 | that we got before releasing the polling island lock). This is because |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1297 | pollset->po.pi pointer might get udpated in other parts of the |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1298 | code when there is an island merge while we are doing epoll_wait() above */ |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 1299 | PI_UNREF(exec_ctx, pi, "ps_work"); |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 1300 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1301 | GPR_TIMER_END("pollset_work_and_unlock", 0); |
| 1302 | } |
| 1303 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1304 | /* pollset->po.mu lock must be held by the caller before calling this. |
| 1305 | The function pollset_work() may temporarily release the lock (pollset->po.mu) |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1306 | during the course of its execution but it will always re-acquire the lock and |
| 1307 | ensure that it is held by the time the function returns */ |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1308 | static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, |
| 1309 | grpc_pollset_worker **worker_hdl, |
| 1310 | gpr_timespec now, gpr_timespec deadline) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1311 | GPR_TIMER_BEGIN("pollset_work", 0); |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1312 | grpc_error *error = GRPC_ERROR_NONE; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1313 | int timeout_ms = poll_deadline_to_millis_timeout(deadline, now); |
| 1314 | |
| 1315 | sigset_t new_mask; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1316 | |
| 1317 | grpc_pollset_worker worker; |
| 1318 | worker.next = worker.prev = NULL; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1319 | worker.pt_id = pthread_self(); |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1320 | gpr_atm_no_barrier_store(&worker.is_kicked, (gpr_atm)0); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1321 | |
Craig Tiller | 557c88c | 2017-04-05 17:20:18 -0700 | [diff] [blame] | 1322 | if (worker_hdl) *worker_hdl = &worker; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1323 | |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1324 | gpr_tls_set(&g_current_thread_pollset, (intptr_t)pollset); |
| 1325 | gpr_tls_set(&g_current_thread_worker, (intptr_t)&worker); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1326 | |
| 1327 | if (pollset->kicked_without_pollers) { |
| 1328 | /* If the pollset was kicked without pollers, pretend that the current |
| 1329 | worker got the kick and skip polling. A kick indicates that there is some |
| 1330 | work that needs attention like an event on the completion queue or an |
| 1331 | alarm */ |
| 1332 | GPR_TIMER_MARK("pollset_work.kicked_without_pollers", 0); |
| 1333 | pollset->kicked_without_pollers = 0; |
| 1334 | } else if (!pollset->shutting_down) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1335 | /* We use the posix-signal with number 'grpc_wakeup_signal' for waking up |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1336 | (i.e 'kicking') a worker in the pollset. A 'kick' is a way to inform the |
| 1337 | worker that there is some pending work that needs immediate attention |
| 1338 | (like an event on the completion queue, or a polling island merge that |
| 1339 | results in a new epoll-fd to wait on) and that the worker should not |
| 1340 | spend time waiting in epoll_pwait(). |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1341 | |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1342 | A worker can be kicked anytime from the point it is added to the pollset |
| 1343 | via push_front_worker() (or push_back_worker()) to the point it is |
| 1344 | removed via remove_worker(). |
| 1345 | If the worker is kicked before/during it calls epoll_pwait(), it should |
| 1346 | immediately exit from epoll_wait(). If the worker is kicked after it |
| 1347 | returns from epoll_wait(), then nothing really needs to be done. |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1348 | |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1349 | To accomplish this, we mask 'grpc_wakeup_signal' on this thread at all |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1350 | times *except* when it is in epoll_pwait(). This way, the worker never |
| 1351 | misses acting on a kick */ |
| 1352 | |
Craig Tiller | 1919699 | 2016-06-27 18:45:56 -0700 | [diff] [blame] | 1353 | if (!g_initialized_sigmask) { |
| 1354 | sigemptyset(&new_mask); |
| 1355 | sigaddset(&new_mask, grpc_wakeup_signal); |
| 1356 | pthread_sigmask(SIG_BLOCK, &new_mask, &g_orig_sigmask); |
| 1357 | sigdelset(&g_orig_sigmask, grpc_wakeup_signal); |
| 1358 | g_initialized_sigmask = true; |
| 1359 | /* new_mask: The new thread mask which blocks 'grpc_wakeup_signal'. |
| 1360 | This is the mask used at all times *except during |
| 1361 | epoll_wait()*" |
| 1362 | g_orig_sigmask: The thread mask which allows 'grpc_wakeup_signal' and |
Craig Tiller | 510ff69 | 2016-06-27 20:31:49 -0700 | [diff] [blame] | 1363 | this is the mask to use *during epoll_wait()* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1364 | |
Craig Tiller | 1919699 | 2016-06-27 18:45:56 -0700 | [diff] [blame] | 1365 | The new_mask is set on the worker before it is added to the pollset |
Craig Tiller | 510ff69 | 2016-06-27 20:31:49 -0700 | [diff] [blame] | 1366 | (i.e before it can be kicked) */ |
Craig Tiller | 1919699 | 2016-06-27 18:45:56 -0700 | [diff] [blame] | 1367 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1368 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1369 | push_front_worker(pollset, &worker); /* Add worker to pollset */ |
| 1370 | |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1371 | pollset_work_and_unlock(exec_ctx, pollset, &worker, timeout_ms, |
| 1372 | &g_orig_sigmask, &error); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1373 | grpc_exec_ctx_flush(exec_ctx); |
| 1374 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1375 | gpr_mu_lock(&pollset->po.mu); |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1376 | |
| 1377 | /* Note: There is no need to reset worker.is_kicked to 0 since we are no |
| 1378 | longer going to use this worker */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1379 | remove_worker(pollset, &worker); |
| 1380 | } |
| 1381 | |
| 1382 | /* If we are the last worker on the pollset (i.e pollset_has_workers() is |
| 1383 | false at this point) and the pollset is shutting down, we may have to |
| 1384 | finish the shutdown process by calling finish_shutdown_locked(). |
| 1385 | See pollset_shutdown() for more details. |
| 1386 | |
| 1387 | Note: Continuing to access pollset here is safe; it is the caller's |
| 1388 | responsibility to not destroy a pollset when it has outstanding calls to |
| 1389 | pollset_work() */ |
| 1390 | if (pollset->shutting_down && !pollset_has_workers(pollset) && |
| 1391 | !pollset->finish_shutdown_called) { |
| 1392 | GPR_TIMER_MARK("pollset_work.finish_shutdown_locked", 0); |
| 1393 | finish_shutdown_locked(exec_ctx, pollset); |
| 1394 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1395 | gpr_mu_unlock(&pollset->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1396 | grpc_exec_ctx_flush(exec_ctx); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1397 | gpr_mu_lock(&pollset->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1398 | } |
| 1399 | |
Craig Tiller | 557c88c | 2017-04-05 17:20:18 -0700 | [diff] [blame] | 1400 | if (worker_hdl) *worker_hdl = NULL; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1401 | |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1402 | gpr_tls_set(&g_current_thread_pollset, (intptr_t)0); |
| 1403 | gpr_tls_set(&g_current_thread_worker, (intptr_t)0); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1404 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1405 | GPR_TIMER_END("pollset_work", 0); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1406 | |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1407 | GRPC_LOG_IF_ERROR("pollset_work", GRPC_ERROR_REF(error)); |
| 1408 | return error; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1409 | } |
| 1410 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1411 | static void add_poll_object(grpc_exec_ctx *exec_ctx, poll_obj *bag, |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1412 | poll_obj_type bag_type, poll_obj *item, |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1413 | poll_obj_type item_type) { |
| 1414 | GPR_TIMER_BEGIN("add_poll_object", 0); |
| 1415 | |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame^] | 1416 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1417 | GPR_ASSERT(item->obj_type == item_type); |
| 1418 | GPR_ASSERT(bag->obj_type == bag_type); |
| 1419 | #endif |
Craig Tiller | 57726ca | 2016-09-12 11:59:45 -0700 | [diff] [blame] | 1420 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1421 | grpc_error *error = GRPC_ERROR_NONE; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 1422 | polling_island *pi_new = NULL; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1423 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1424 | gpr_mu_lock(&bag->mu); |
| 1425 | gpr_mu_lock(&item->mu); |
| 1426 | |
Craig Tiller | 7212c23 | 2016-07-06 13:11:09 -0700 | [diff] [blame] | 1427 | retry: |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1428 | /* |
| 1429 | * 1) If item->pi and bag->pi are both non-NULL and equal, do nothing |
| 1430 | * 2) If item->pi and bag->pi are both NULL, create a new polling island (with |
| 1431 | * a refcount of 2) and point item->pi and bag->pi to the new island |
| 1432 | * 3) If exactly one of item->pi or bag->pi is NULL, update it to point to |
| 1433 | * the other's non-NULL pi |
| 1434 | * 4) Finally if item->pi and bag-pi are non-NULL and not-equal, merge the |
| 1435 | * polling islands and update item->pi and bag->pi to point to the new |
| 1436 | * island |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1437 | */ |
Craig Tiller | 8e8027b | 2016-07-07 10:42:09 -0700 | [diff] [blame] | 1438 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1439 | /* Early out if we are trying to add an 'fd' to a 'bag' but the fd is already |
| 1440 | * orphaned */ |
| 1441 | if (item_type == POLL_OBJ_FD && (FD_FROM_PO(item))->orphaned) { |
| 1442 | gpr_mu_unlock(&item->mu); |
| 1443 | gpr_mu_unlock(&bag->mu); |
Craig Tiller | 42ac6db | 2016-07-06 17:13:56 -0700 | [diff] [blame] | 1444 | return; |
| 1445 | } |
| 1446 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1447 | if (item->pi == bag->pi) { |
| 1448 | pi_new = item->pi; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 1449 | if (pi_new == NULL) { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1450 | /* GPR_ASSERT(item->pi == bag->pi == NULL) */ |
Sree Kuchibhotla | a129adf | 2016-10-26 16:44:44 -0700 | [diff] [blame] | 1451 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1452 | /* If we are adding an fd to a bag (i.e pollset or pollset_set), then |
| 1453 | * we need to do some extra work to make TSAN happy */ |
| 1454 | if (item_type == POLL_OBJ_FD) { |
| 1455 | /* Unlock before creating a new polling island: the polling island will |
| 1456 | create a workqueue which creates a file descriptor, and holding an fd |
| 1457 | lock here can eventually cause a loop to appear to TSAN (making it |
| 1458 | unhappy). We don't think it's a real loop (there's an epoch point |
| 1459 | where that loop possibility disappears), but the advantages of |
| 1460 | keeping TSAN happy outweigh any performance advantage we might have |
| 1461 | by keeping the lock held. */ |
| 1462 | gpr_mu_unlock(&item->mu); |
| 1463 | pi_new = polling_island_create(exec_ctx, FD_FROM_PO(item), &error); |
| 1464 | gpr_mu_lock(&item->mu); |
Sree Kuchibhotla | a129adf | 2016-10-26 16:44:44 -0700 | [diff] [blame] | 1465 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1466 | /* Need to reverify any assumptions made between the initial lock and |
| 1467 | getting to this branch: if they've changed, we need to throw away our |
| 1468 | work and figure things out again. */ |
| 1469 | if (item->pi != NULL) { |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1470 | GRPC_POLLING_TRACE( |
| 1471 | "add_poll_object: Raced creating new polling island. pi_new: %p " |
| 1472 | "(fd: %d, %s: %p)", |
| 1473 | (void *)pi_new, FD_FROM_PO(item)->fd, poll_obj_string(bag_type), |
| 1474 | (void *)bag); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1475 | /* No need to lock 'pi_new' here since this is a new polling island |
Sree Kuchibhotla | 8214b87 | 2017-02-23 12:49:48 -0800 | [diff] [blame] | 1476 | and no one has a reference to it yet */ |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1477 | polling_island_remove_all_fds_locked(pi_new, true, &error); |
| 1478 | |
| 1479 | /* Ref and unref so that the polling island gets deleted during unref |
| 1480 | */ |
| 1481 | PI_ADD_REF(pi_new, "dance_of_destruction"); |
| 1482 | PI_UNREF(exec_ctx, pi_new, "dance_of_destruction"); |
| 1483 | goto retry; |
| 1484 | } |
Craig Tiller | 27da642 | 2016-07-06 13:14:46 -0700 | [diff] [blame] | 1485 | } else { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1486 | pi_new = polling_island_create(exec_ctx, NULL, &error); |
Craig Tiller | 7212c23 | 2016-07-06 13:11:09 -0700 | [diff] [blame] | 1487 | } |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1488 | |
| 1489 | GRPC_POLLING_TRACE( |
| 1490 | "add_poll_object: Created new polling island. pi_new: %p (%s: %p, " |
| 1491 | "%s: %p)", |
| 1492 | (void *)pi_new, poll_obj_string(item_type), (void *)item, |
| 1493 | poll_obj_string(bag_type), (void *)bag); |
| 1494 | } else { |
| 1495 | GRPC_POLLING_TRACE( |
| 1496 | "add_poll_object: Same polling island. pi: %p (%s, %s)", |
| 1497 | (void *)pi_new, poll_obj_string(item_type), |
| 1498 | poll_obj_string(bag_type)); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1499 | } |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1500 | } else if (item->pi == NULL) { |
| 1501 | /* GPR_ASSERT(bag->pi != NULL) */ |
| 1502 | /* Make pi_new point to latest pi*/ |
| 1503 | pi_new = polling_island_lock(bag->pi); |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1504 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1505 | if (item_type == POLL_OBJ_FD) { |
| 1506 | grpc_fd *fd = FD_FROM_PO(item); |
| 1507 | polling_island_add_fds_locked(pi_new, &fd, 1, true, &error); |
| 1508 | } |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1509 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1510 | gpr_mu_unlock(&pi_new->mu); |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1511 | GRPC_POLLING_TRACE( |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1512 | "add_poll_obj: item->pi was NULL. pi_new: %p (item(%s): %p, " |
| 1513 | "bag(%s): %p)", |
| 1514 | (void *)pi_new, poll_obj_string(item_type), (void *)item, |
| 1515 | poll_obj_string(bag_type), (void *)bag); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1516 | } else if (bag->pi == NULL) { |
| 1517 | /* GPR_ASSERT(item->pi != NULL) */ |
| 1518 | /* Make pi_new to point to latest pi */ |
| 1519 | pi_new = polling_island_lock(item->pi); |
| 1520 | gpr_mu_unlock(&pi_new->mu); |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1521 | GRPC_POLLING_TRACE( |
| 1522 | "add_poll_obj: bag->pi was NULL. pi_new: %p (item(%s): %p, " |
| 1523 | "bag(%s): %p)", |
| 1524 | (void *)pi_new, poll_obj_string(item_type), (void *)item, |
| 1525 | poll_obj_string(bag_type), (void *)bag); |
Sree Kuchibhotla | 5098f91 | 2016-05-31 10:58:17 -0700 | [diff] [blame] | 1526 | } else { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1527 | pi_new = polling_island_merge(item->pi, bag->pi, &error); |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1528 | GRPC_POLLING_TRACE( |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1529 | "add_poll_obj: polling islands merged. pi_new: %p (item(%s): %p, " |
| 1530 | "bag(%s): %p)", |
| 1531 | (void *)pi_new, poll_obj_string(item_type), (void *)item, |
| 1532 | poll_obj_string(bag_type), (void *)bag); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1533 | } |
| 1534 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1535 | /* At this point, pi_new is the polling island that both item->pi and bag->pi |
| 1536 | MUST be pointing to */ |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1537 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1538 | if (item->pi != pi_new) { |
| 1539 | PI_ADD_REF(pi_new, poll_obj_string(item_type)); |
| 1540 | if (item->pi != NULL) { |
| 1541 | PI_UNREF(exec_ctx, item->pi, poll_obj_string(item_type)); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1542 | } |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1543 | item->pi = pi_new; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1544 | } |
| 1545 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1546 | if (bag->pi != pi_new) { |
| 1547 | PI_ADD_REF(pi_new, poll_obj_string(bag_type)); |
| 1548 | if (bag->pi != NULL) { |
| 1549 | PI_UNREF(exec_ctx, bag->pi, poll_obj_string(bag_type)); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1550 | } |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1551 | bag->pi = pi_new; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1552 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1553 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1554 | gpr_mu_unlock(&item->mu); |
| 1555 | gpr_mu_unlock(&bag->mu); |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 1556 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1557 | GRPC_LOG_IF_ERROR("add_poll_object", error); |
| 1558 | GPR_TIMER_END("add_poll_object", 0); |
| 1559 | } |
Craig Tiller | 57726ca | 2016-09-12 11:59:45 -0700 | [diff] [blame] | 1560 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 1561 | static void pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, |
| 1562 | grpc_fd *fd) { |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1563 | add_poll_object(exec_ctx, &pollset->po, POLL_OBJ_POLLSET, &fd->po, |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1564 | POLL_OBJ_FD); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1565 | } |
| 1566 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1567 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1568 | * Pollset-set Definitions |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1569 | */ |
| 1570 | |
| 1571 | static grpc_pollset_set *pollset_set_create(void) { |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1572 | grpc_pollset_set *pss = gpr_malloc(sizeof(*pss)); |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1573 | gpr_mu_init(&pss->po.mu); |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1574 | pss->po.pi = NULL; |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame^] | 1575 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1576 | pss->po.obj_type = POLL_OBJ_POLLSET_SET; |
| 1577 | #endif |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1578 | return pss; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1579 | } |
| 1580 | |
Craig Tiller | 9e5ac1b | 2017-02-14 22:25:50 -0800 | [diff] [blame] | 1581 | static void pollset_set_destroy(grpc_exec_ctx *exec_ctx, |
| 1582 | grpc_pollset_set *pss) { |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1583 | gpr_mu_destroy(&pss->po.mu); |
| 1584 | |
| 1585 | if (pss->po.pi != NULL) { |
Craig Tiller | 9e5ac1b | 2017-02-14 22:25:50 -0800 | [diff] [blame] | 1586 | PI_UNREF(exec_ctx, pss->po.pi, "pss_destroy"); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1587 | } |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1588 | |
| 1589 | gpr_free(pss); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1590 | } |
| 1591 | |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1592 | static void pollset_set_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss, |
| 1593 | grpc_fd *fd) { |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1594 | add_poll_object(exec_ctx, &pss->po, POLL_OBJ_POLLSET_SET, &fd->po, |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1595 | POLL_OBJ_FD); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1596 | } |
| 1597 | |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1598 | static void pollset_set_del_fd(grpc_exec_ctx *exec_ctx, grpc_pollset_set *pss, |
| 1599 | grpc_fd *fd) { |
| 1600 | /* Nothing to do */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1601 | } |
| 1602 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1603 | static void pollset_set_add_pollset(grpc_exec_ctx *exec_ctx, |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1604 | grpc_pollset_set *pss, grpc_pollset *ps) { |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1605 | add_poll_object(exec_ctx, &pss->po, POLL_OBJ_POLLSET_SET, &ps->po, |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1606 | POLL_OBJ_POLLSET); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1607 | } |
| 1608 | |
| 1609 | static void pollset_set_del_pollset(grpc_exec_ctx *exec_ctx, |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1610 | grpc_pollset_set *pss, grpc_pollset *ps) { |
| 1611 | /* Nothing to do */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1612 | } |
| 1613 | |
| 1614 | static void pollset_set_add_pollset_set(grpc_exec_ctx *exec_ctx, |
| 1615 | grpc_pollset_set *bag, |
| 1616 | grpc_pollset_set *item) { |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1617 | add_poll_object(exec_ctx, &bag->po, POLL_OBJ_POLLSET_SET, &item->po, |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1618 | POLL_OBJ_POLLSET_SET); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1619 | } |
| 1620 | |
| 1621 | static void pollset_set_del_pollset_set(grpc_exec_ctx *exec_ctx, |
| 1622 | grpc_pollset_set *bag, |
| 1623 | grpc_pollset_set *item) { |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1624 | /* Nothing to do */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1625 | } |
| 1626 | |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1627 | /* Test helper functions |
| 1628 | * */ |
| 1629 | void *grpc_fd_get_polling_island(grpc_fd *fd) { |
| 1630 | polling_island *pi; |
| 1631 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1632 | gpr_mu_lock(&fd->po.mu); |
| 1633 | pi = fd->po.pi; |
| 1634 | gpr_mu_unlock(&fd->po.mu); |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1635 | |
| 1636 | return pi; |
| 1637 | } |
| 1638 | |
| 1639 | void *grpc_pollset_get_polling_island(grpc_pollset *ps) { |
| 1640 | polling_island *pi; |
| 1641 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1642 | gpr_mu_lock(&ps->po.mu); |
| 1643 | pi = ps->po.pi; |
| 1644 | gpr_mu_unlock(&ps->po.mu); |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1645 | |
| 1646 | return pi; |
| 1647 | } |
| 1648 | |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1649 | bool grpc_are_polling_islands_equal(void *p, void *q) { |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1650 | polling_island *p1 = p; |
| 1651 | polling_island *p2 = q; |
| 1652 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1653 | /* Note: polling_island_lock_pair() may change p1 and p2 to point to the |
| 1654 | latest polling islands in their respective linked lists */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1655 | polling_island_lock_pair(&p1, &p2); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1656 | polling_island_unlock_pair(p1, p2); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1657 | |
| 1658 | return p1 == p2; |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1659 | } |
| 1660 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1661 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1662 | * Event engine binding |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1663 | */ |
| 1664 | |
| 1665 | static void shutdown_engine(void) { |
| 1666 | fd_global_shutdown(); |
| 1667 | pollset_global_shutdown(); |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 1668 | polling_island_global_shutdown(); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1669 | } |
| 1670 | |
| 1671 | static const grpc_event_engine_vtable vtable = { |
| 1672 | .pollset_size = sizeof(grpc_pollset), |
| 1673 | |
| 1674 | .fd_create = fd_create, |
| 1675 | .fd_wrapped_fd = fd_wrapped_fd, |
| 1676 | .fd_orphan = fd_orphan, |
| 1677 | .fd_shutdown = fd_shutdown, |
Sree Kuchibhotla | 24b6eae | 2016-06-21 18:01:14 -0700 | [diff] [blame] | 1678 | .fd_is_shutdown = fd_is_shutdown, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1679 | .fd_notify_on_read = fd_notify_on_read, |
| 1680 | .fd_notify_on_write = fd_notify_on_write, |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 1681 | .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1682 | |
| 1683 | .pollset_init = pollset_init, |
| 1684 | .pollset_shutdown = pollset_shutdown, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1685 | .pollset_destroy = pollset_destroy, |
| 1686 | .pollset_work = pollset_work, |
| 1687 | .pollset_kick = pollset_kick, |
| 1688 | .pollset_add_fd = pollset_add_fd, |
| 1689 | |
| 1690 | .pollset_set_create = pollset_set_create, |
| 1691 | .pollset_set_destroy = pollset_set_destroy, |
| 1692 | .pollset_set_add_pollset = pollset_set_add_pollset, |
| 1693 | .pollset_set_del_pollset = pollset_set_del_pollset, |
| 1694 | .pollset_set_add_pollset_set = pollset_set_add_pollset_set, |
| 1695 | .pollset_set_del_pollset_set = pollset_set_del_pollset_set, |
| 1696 | .pollset_set_add_fd = pollset_set_add_fd, |
| 1697 | .pollset_set_del_fd = pollset_set_del_fd, |
| 1698 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1699 | .shutdown_engine = shutdown_engine, |
| 1700 | }; |
| 1701 | |
Sree Kuchibhotla | 7274402 | 2016-06-09 09:42:06 -0700 | [diff] [blame] | 1702 | /* It is possible that GLIBC has epoll but the underlying kernel doesn't. |
| 1703 | * Create a dummy epoll_fd to make sure epoll support is available */ |
| 1704 | static bool is_epoll_available() { |
| 1705 | int fd = epoll_create1(EPOLL_CLOEXEC); |
| 1706 | if (fd < 0) { |
| 1707 | gpr_log( |
| 1708 | GPR_ERROR, |
| 1709 | "epoll_create1 failed with error: %d. Not using epoll polling engine", |
| 1710 | fd); |
| 1711 | return false; |
| 1712 | } |
| 1713 | close(fd); |
| 1714 | return true; |
| 1715 | } |
| 1716 | |
Craig Tiller | f8382b8 | 2017-04-27 15:09:48 -0700 | [diff] [blame] | 1717 | const grpc_event_engine_vtable *grpc_init_epollsig_linux( |
| 1718 | bool explicit_request) { |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1719 | /* If use of signals is disabled, we cannot use epoll engine*/ |
| 1720 | if (is_grpc_wakeup_signal_initialized && grpc_wakeup_signal < 0) { |
| 1721 | return NULL; |
| 1722 | } |
| 1723 | |
Ken Payson | cd7d047 | 2016-10-11 12:24:20 -0700 | [diff] [blame] | 1724 | if (!grpc_has_wakeup_fd()) { |
Ken Payson | bc544be | 2016-10-06 19:23:47 -0700 | [diff] [blame] | 1725 | return NULL; |
| 1726 | } |
| 1727 | |
Sree Kuchibhotla | 7274402 | 2016-06-09 09:42:06 -0700 | [diff] [blame] | 1728 | if (!is_epoll_available()) { |
| 1729 | return NULL; |
| 1730 | } |
| 1731 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1732 | if (!is_grpc_wakeup_signal_initialized) { |
Craig Tiller | bc0ab08 | 2017-05-05 10:42:44 -0700 | [diff] [blame] | 1733 | /* TODO(ctiller): when other epoll engines are ready, remove the true || to |
| 1734 | * force this to be explitly chosen if needed */ |
Craig Tiller | 924353a | 2017-05-05 17:36:31 +0000 | [diff] [blame] | 1735 | if (true || explicit_request) { |
Craig Tiller | f8382b8 | 2017-04-27 15:09:48 -0700 | [diff] [blame] | 1736 | grpc_use_signal(SIGRTMIN + 6); |
| 1737 | } else { |
| 1738 | return NULL; |
| 1739 | } |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1740 | } |
| 1741 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1742 | fd_global_init(); |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1743 | |
| 1744 | if (!GRPC_LOG_IF_ERROR("pollset_global_init", pollset_global_init())) { |
| 1745 | return NULL; |
| 1746 | } |
| 1747 | |
| 1748 | if (!GRPC_LOG_IF_ERROR("polling_island_global_init", |
| 1749 | polling_island_global_init())) { |
| 1750 | return NULL; |
| 1751 | } |
| 1752 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1753 | return &vtable; |
| 1754 | } |
| 1755 | |
murgatroid99 | 623dd4f | 2016-08-08 17:31:27 -0700 | [diff] [blame] | 1756 | #else /* defined(GRPC_LINUX_EPOLL) */ |
| 1757 | #if defined(GRPC_POSIX_SOCKET) |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 1758 | #include "src/core/lib/iomgr/ev_posix.h" |
murgatroid99 | 623dd4f | 2016-08-08 17:31:27 -0700 | [diff] [blame] | 1759 | /* If GRPC_LINUX_EPOLL is not defined, it means epoll is not available. Return |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 1760 | * NULL */ |
Craig Tiller | f8382b8 | 2017-04-27 15:09:48 -0700 | [diff] [blame] | 1761 | const grpc_event_engine_vtable *grpc_init_epollsig_linux( |
| 1762 | bool explicit_request) { |
| 1763 | return NULL; |
| 1764 | } |
murgatroid99 | 623dd4f | 2016-08-08 17:31:27 -0700 | [diff] [blame] | 1765 | #endif /* defined(GRPC_POSIX_SOCKET) */ |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 1766 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1767 | void grpc_use_signal(int signum) {} |
murgatroid99 | 623dd4f | 2016-08-08 17:31:27 -0700 | [diff] [blame] | 1768 | #endif /* !defined(GRPC_LINUX_EPOLL) */ |