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 | |
Alexander Polcyn | db3e898 | 2018-02-21 16:59:24 -0800 | [diff] [blame] | 19 | #include <grpc/support/port_platform.h> |
| 20 | |
murgatroid99 | 5407089 | 2016-08-08 17:01:18 -0700 | [diff] [blame] | 21 | #include "src/core/lib/iomgr/port.h" |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 22 | |
Yash Tibrewal | 4e0fe52 | 2017-10-08 18:07:15 -0700 | [diff] [blame] | 23 | #include <grpc/grpc_posix.h> |
yang-g | ceb2475 | 2017-11-07 12:06:37 -0800 | [diff] [blame] | 24 | #include <grpc/support/log.h> |
Yash Tibrewal | 4e0fe52 | 2017-10-08 18:07:15 -0700 | [diff] [blame] | 25 | |
Sree Kuchibhotla | 76a0795 | 2016-06-22 15:09:06 -0700 | [diff] [blame] | 26 | /* This polling engine is only relevant on linux kernels supporting epoll() */ |
Mehrdad Afshari | fb66900 | 2018-01-17 15:37:56 -0800 | [diff] [blame] | 27 | #ifdef GRPC_LINUX_EPOLL_CREATE1 |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 28 | |
Craig Tiller | 4509c47 | 2017-04-27 19:05:13 +0000 | [diff] [blame] | 29 | #include "src/core/lib/iomgr/ev_epollsig_linux.h" |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 30 | |
| 31 | #include <assert.h> |
| 32 | #include <errno.h> |
Craig Tiller | 2039779 | 2017-07-18 11:35:27 -0700 | [diff] [blame] | 33 | #include <limits.h> |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 34 | #include <poll.h> |
Sree Kuchibhotla | 4998e30 | 2016-08-16 07:26:31 -0700 | [diff] [blame] | 35 | #include <pthread.h> |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 36 | #include <signal.h> |
| 37 | #include <string.h> |
| 38 | #include <sys/epoll.h> |
| 39 | #include <sys/socket.h> |
| 40 | #include <unistd.h> |
| 41 | |
| 42 | #include <grpc/support/alloc.h> |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 43 | #include <grpc/support/string_util.h> |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 44 | |
Craig Tiller | b4bb1cd | 2017-07-20 14:18:17 -0700 | [diff] [blame] | 45 | #include "src/core/lib/debug/stats.h" |
Vijay Pai | b6cf123 | 2018-01-25 21:02:26 -0800 | [diff] [blame] | 46 | #include "src/core/lib/gpr/tls.h" |
Vijay Pai | d4d0a30 | 2018-01-25 13:24:03 -0800 | [diff] [blame] | 47 | #include "src/core/lib/gpr/useful.h" |
Mark D. Roth | 4f2b0fd | 2018-01-19 12:12:23 -0800 | [diff] [blame] | 48 | #include "src/core/lib/gprpp/manual_constructor.h" |
Craig Tiller | 6b7c1fb | 2017-07-19 15:45:03 -0700 | [diff] [blame] | 49 | #include "src/core/lib/iomgr/block_annotate.h" |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 50 | #include "src/core/lib/iomgr/ev_posix.h" |
| 51 | #include "src/core/lib/iomgr/iomgr_internal.h" |
Craig Tiller | 376887d | 2017-04-06 08:27:03 -0700 | [diff] [blame] | 52 | #include "src/core/lib/iomgr/lockfree_event.h" |
Craig Tiller | 185f6c9 | 2017-03-17 08:33:19 -0700 | [diff] [blame] | 53 | #include "src/core/lib/iomgr/timer.h" |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 54 | #include "src/core/lib/iomgr/wakeup_fd_posix.h" |
| 55 | #include "src/core/lib/profiling/timers.h" |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 56 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 57 | #define GRPC_POLLSET_KICK_BROADCAST ((grpc_pollset_worker*)1) |
Craig Tiller | e24b24d | 2017-04-06 16:05:45 -0700 | [diff] [blame] | 58 | |
Noah Eisen | c384d81 | 2017-11-12 20:14:27 -0800 | [diff] [blame] | 59 | #define GRPC_POLLING_TRACE(...) \ |
ncteisen | 9ffb149 | 2017-11-10 14:00:49 -0800 | [diff] [blame] | 60 | if (grpc_polling_trace.enabled()) { \ |
Noah Eisen | c384d81 | 2017-11-12 20:14:27 -0800 | [diff] [blame] | 61 | gpr_log(GPR_INFO, __VA_ARGS__); \ |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 62 | } |
| 63 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 64 | static int grpc_wakeup_signal = -1; |
| 65 | static bool is_grpc_wakeup_signal_initialized = false; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 66 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 67 | /* Implements the function defined in grpc_posix.h. This function might be |
| 68 | * called before even calling grpc_init() to set either a different signal to |
| 69 | * use. If signum == -1, then the use of signals is disabled */ |
| 70 | void grpc_use_signal(int signum) { |
| 71 | grpc_wakeup_signal = signum; |
| 72 | is_grpc_wakeup_signal_initialized = true; |
| 73 | |
| 74 | if (grpc_wakeup_signal < 0) { |
| 75 | gpr_log(GPR_INFO, |
| 76 | "Use of signals is disabled. Epoll engine will not be used"); |
| 77 | } else { |
| 78 | gpr_log(GPR_INFO, "epoll engine will be using signal: %d", |
| 79 | grpc_wakeup_signal); |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | struct polling_island; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 84 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 85 | typedef enum { |
| 86 | POLL_OBJ_FD, |
| 87 | POLL_OBJ_POLLSET, |
| 88 | POLL_OBJ_POLLSET_SET |
| 89 | } poll_obj_type; |
| 90 | |
| 91 | typedef struct poll_obj { |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame] | 92 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 93 | poll_obj_type obj_type; |
| 94 | #endif |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 95 | gpr_mu mu; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 96 | struct polling_island* pi; |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 97 | } poll_obj; |
| 98 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 99 | const char* poll_obj_string(poll_obj_type po_type) { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 100 | switch (po_type) { |
| 101 | case POLL_OBJ_FD: |
| 102 | return "fd"; |
| 103 | case POLL_OBJ_POLLSET: |
| 104 | return "pollset"; |
| 105 | case POLL_OBJ_POLLSET_SET: |
| 106 | return "pollset_set"; |
| 107 | } |
| 108 | |
| 109 | GPR_UNREACHABLE_CODE(return "UNKNOWN"); |
| 110 | } |
| 111 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 112 | /******************************************************************************* |
| 113 | * Fd Declarations |
| 114 | */ |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 115 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 116 | #define FD_FROM_PO(po) ((grpc_fd*)(po)) |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 117 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 118 | struct grpc_fd { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 119 | poll_obj po; |
| 120 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 121 | int fd; |
| 122 | /* refst format: |
Sree Kuchibhotla | 5098f91 | 2016-05-31 10:58:17 -0700 | [diff] [blame] | 123 | bit 0 : 1=Active / 0=Orphaned |
| 124 | bits 1-n : refcount |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 125 | Ref/Unref by two to avoid altering the orphaned bit */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 126 | gpr_atm refst; |
| 127 | |
Sree Kuchibhotla | 9998338 | 2017-02-12 17:03:27 -0800 | [diff] [blame] | 128 | /* The fd is either closed or we relinquished control of it. In either |
| 129 | cases, this indicates that the 'fd' on this structure is no longer |
| 130 | valid */ |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 131 | bool orphaned; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 132 | |
Craig Tiller | fbf61bb | 2017-11-08 11:50:14 -0800 | [diff] [blame] | 133 | grpc_core::ManualConstructor<grpc_core::LockfreeEvent> read_closure; |
| 134 | grpc_core::ManualConstructor<grpc_core::LockfreeEvent> write_closure; |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 135 | grpc_core::ManualConstructor<grpc_core::LockfreeEvent> error_closure; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 136 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 137 | struct grpc_fd* freelist_next; |
| 138 | grpc_closure* on_done_closure; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 139 | |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 140 | /* The pollset that last noticed that the fd is readable. The actual type |
| 141 | * stored in this is (grpc_pollset *) */ |
| 142 | gpr_atm read_notifier_pollset; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 143 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 144 | grpc_iomgr_object iomgr_object; |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 145 | |
| 146 | /* Do we need to track EPOLLERR events separately? */ |
| 147 | bool track_err; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 148 | }; |
| 149 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 150 | /* Reference counting for fds */ |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 151 | #ifndef NDEBUG |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 152 | static void fd_ref(grpc_fd* fd, const char* reason, const char* file, int line); |
| 153 | static void fd_unref(grpc_fd* fd, const char* reason, const char* file, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 154 | int line); |
| 155 | #define GRPC_FD_REF(fd, reason) fd_ref(fd, reason, __FILE__, __LINE__) |
| 156 | #define GRPC_FD_UNREF(fd, reason) fd_unref(fd, reason, __FILE__, __LINE__) |
| 157 | #else |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 158 | static void fd_ref(grpc_fd* fd); |
| 159 | static void fd_unref(grpc_fd* fd); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 160 | #define GRPC_FD_REF(fd, reason) fd_ref(fd) |
| 161 | #define GRPC_FD_UNREF(fd, reason) fd_unref(fd) |
| 162 | #endif |
| 163 | |
| 164 | static void fd_global_init(void); |
| 165 | static void fd_global_shutdown(void); |
| 166 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 167 | /******************************************************************************* |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 168 | * Polling island Declarations |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 169 | */ |
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 | #ifndef NDEBUG |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 172 | |
Sree Kuchibhotla | 6a29545 | 2016-06-23 15:53:10 -0700 | [diff] [blame] | 173 | #define PI_ADD_REF(p, r) pi_add_ref_dbg((p), (r), __FILE__, __LINE__) |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 174 | #define PI_UNREF(p, r) pi_unref_dbg((p), (r), __FILE__, __LINE__) |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 175 | |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 176 | #else |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 177 | |
Sree Kuchibhotla | 6a29545 | 2016-06-23 15:53:10 -0700 | [diff] [blame] | 178 | #define PI_ADD_REF(p, r) pi_add_ref((p)) |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 179 | #define PI_UNREF(p, r) pi_unref((p)) |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 180 | |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 181 | #endif |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 182 | |
Craig Tiller | 460502e | 2016-10-13 10:02:08 -0700 | [diff] [blame] | 183 | /* This is also used as grpc_workqueue (by directly casing it) */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 184 | typedef struct polling_island { |
| 185 | gpr_mu mu; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 186 | /* Ref count. Use PI_ADD_REF() and PI_UNREF() macros to increment/decrement |
| 187 | the refcount. |
| 188 | Once the ref count becomes zero, this structure is destroyed which means |
| 189 | we should ensure that there is never a scenario where a PI_ADD_REF() is |
| 190 | racing with a PI_UNREF() that just made the ref_count zero. */ |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 191 | gpr_atm ref_count; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 192 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 193 | /* Pointer to the polling_island this merged into. |
| 194 | * merged_to value is only set once in polling_island's lifetime (and that too |
| 195 | * only if the island is merged with another island). Because of this, we can |
| 196 | * use gpr_atm type here so that we can do atomic access on this and reduce |
| 197 | * lock contention on 'mu' mutex. |
| 198 | * |
| 199 | * Note that if this field is not NULL (i.e not 0), all the remaining fields |
| 200 | * (except mu and ref_count) are invalid and must be ignored. */ |
| 201 | gpr_atm merged_to; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 202 | |
Craig Tiller | 460502e | 2016-10-13 10:02:08 -0700 | [diff] [blame] | 203 | /* Number of threads currently polling on this island */ |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 204 | gpr_atm poller_count; |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 205 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 206 | /* The fd of the underlying epoll set */ |
| 207 | int epoll_fd; |
| 208 | |
| 209 | /* The file descriptors in the epoll set */ |
| 210 | size_t fd_cnt; |
| 211 | size_t fd_capacity; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 212 | grpc_fd** fds; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 213 | } polling_island; |
| 214 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 215 | /******************************************************************************* |
| 216 | * Pollset Declarations |
| 217 | */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 218 | struct grpc_pollset_worker { |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 219 | /* Thread id of this worker */ |
| 220 | pthread_t pt_id; |
| 221 | |
| 222 | /* Used to prevent a worker from getting kicked multiple times */ |
| 223 | gpr_atm is_kicked; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 224 | struct grpc_pollset_worker* next; |
| 225 | struct grpc_pollset_worker* prev; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 226 | }; |
| 227 | |
| 228 | struct grpc_pollset { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 229 | poll_obj po; |
| 230 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 231 | grpc_pollset_worker root_worker; |
| 232 | bool kicked_without_pollers; |
| 233 | |
| 234 | bool shutting_down; /* Is the pollset shutting down ? */ |
| 235 | bool finish_shutdown_called; /* Is the 'finish_shutdown_locked()' called ? */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 236 | grpc_closure* shutdown_done; /* Called after after shutdown is complete */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 237 | }; |
| 238 | |
| 239 | /******************************************************************************* |
| 240 | * Pollset-set Declarations |
| 241 | */ |
| 242 | struct grpc_pollset_set { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 243 | poll_obj po; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 244 | }; |
| 245 | |
| 246 | /******************************************************************************* |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 247 | * Common helpers |
| 248 | */ |
| 249 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 250 | static bool append_error(grpc_error** composite, grpc_error* error, |
| 251 | const char* desc) { |
Craig Tiller | f975f74 | 2016-07-01 14:56:27 -0700 | [diff] [blame] | 252 | if (error == GRPC_ERROR_NONE) return true; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 253 | if (*composite == GRPC_ERROR_NONE) { |
Noah Eisen | 3005ce8 | 2017-03-14 13:38:41 -0700 | [diff] [blame] | 254 | *composite = GRPC_ERROR_CREATE_FROM_COPIED_STRING(desc); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 255 | } |
| 256 | *composite = grpc_error_add_child(*composite, error); |
Craig Tiller | f975f74 | 2016-07-01 14:56:27 -0700 | [diff] [blame] | 257 | return false; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 258 | } |
| 259 | |
| 260 | /******************************************************************************* |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 261 | * Polling island Definitions |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 262 | */ |
| 263 | |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 264 | /* The wakeup fd that is used to wake up all threads in a Polling island. This |
| 265 | is useful in the polling island merge operation where we need to wakeup all |
| 266 | the threads currently polling the smaller polling island (so that they can |
| 267 | start polling the new/merged polling island) |
| 268 | |
| 269 | NOTE: This fd is initialized to be readable and MUST NOT be consumed i.e the |
| 270 | threads that woke up MUST NOT call grpc_wakeup_fd_consume_wakeup() */ |
| 271 | static grpc_wakeup_fd polling_island_wakeup_fd; |
| 272 | |
Craig Tiller | 2e62013 | 2016-10-10 15:27:44 -0700 | [diff] [blame] | 273 | /* The polling island being polled right now. |
| 274 | See comments in workqueue_maybe_wakeup for why this is tracked. */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 275 | static __thread polling_island* g_current_thread_polling_island; |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 276 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 277 | /* Forward declaration */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 278 | static void polling_island_delete(polling_island* pi); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 279 | |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 280 | #ifdef GRPC_TSAN |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 281 | /* Currently TSAN may incorrectly flag data races between epoll_ctl and |
| 282 | epoll_wait for any grpc_fd structs that are added to the epoll set via |
| 283 | epoll_ctl and are returned (within a very short window) via epoll_wait(). |
| 284 | |
| 285 | To work-around this race, we establish a happens-before relation between |
| 286 | the code just-before epoll_ctl() and the code after epoll_wait() by using |
| 287 | this atomic */ |
| 288 | gpr_atm g_epoll_sync; |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 289 | #endif /* defined(GRPC_TSAN) */ |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 290 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 291 | static void pi_add_ref(polling_island* pi); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 292 | static void pi_unref(polling_island* pi); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 293 | |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 294 | #ifndef NDEBUG |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 295 | static void pi_add_ref_dbg(polling_island* pi, const char* reason, |
| 296 | const char* file, int line) { |
ncteisen | 9ffb149 | 2017-11-10 14:00:49 -0800 | [diff] [blame] | 297 | if (grpc_polling_trace.enabled()) { |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 298 | gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count); |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 299 | gpr_log(GPR_DEBUG, |
| 300 | "Add ref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR |
| 301 | " (%s) - (%s, %d)", |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 302 | pi, old_cnt, old_cnt + 1, reason, file, line); |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 303 | } |
| 304 | pi_add_ref(pi); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 305 | } |
| 306 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 307 | static void pi_unref_dbg(polling_island* pi, const char* reason, |
| 308 | const char* file, int line) { |
ncteisen | 9ffb149 | 2017-11-10 14:00:49 -0800 | [diff] [blame] | 309 | if (grpc_polling_trace.enabled()) { |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 310 | gpr_atm old_cnt = gpr_atm_acq_load(&pi->ref_count); |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 311 | gpr_log(GPR_DEBUG, |
| 312 | "Unref pi: %p, old:%" PRIdPTR " -> new:%" PRIdPTR |
| 313 | " (%s) - (%s, %d)", |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 314 | pi, old_cnt, (old_cnt - 1), reason, file, line); |
ncteisen | a135485 | 2017-06-08 16:25:53 -0700 | [diff] [blame] | 315 | } |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 316 | pi_unref(pi); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 317 | } |
| 318 | #endif |
| 319 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 320 | static void pi_add_ref(polling_island* pi) { |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 321 | gpr_atm_no_barrier_fetch_add(&pi->ref_count, 1); |
| 322 | } |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 323 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 324 | static void pi_unref(polling_island* pi) { |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 325 | /* If ref count went to zero, delete the polling island. |
Sree Kuchibhotla | 6a29545 | 2016-06-23 15:53:10 -0700 | [diff] [blame] | 326 | Note that this deletion not be done under a lock. Once the ref count goes |
| 327 | to zero, we are guaranteed that no one else holds a reference to the |
| 328 | 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] | 329 | |
| 330 | Also, if we are deleting the polling island and the merged_to field is |
| 331 | non-empty, we should remove a ref to the merged_to polling island |
| 332 | */ |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 333 | if (1 == gpr_atm_full_fetch_add(&pi->ref_count, -1)) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 334 | polling_island* next = (polling_island*)gpr_atm_acq_load(&pi->merged_to); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 335 | polling_island_delete(pi); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 336 | if (next != nullptr) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 337 | PI_UNREF(next, "pi_delete"); /* Recursive call */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 338 | } |
| 339 | } |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 340 | } |
| 341 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 342 | /* The caller is expected to hold pi->mu lock before calling this function */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 343 | 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] | 344 | size_t fd_count, bool add_fd_refs, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 345 | grpc_error** error) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 346 | int err; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 347 | size_t i; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 348 | struct epoll_event ev; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 349 | char* err_msg; |
| 350 | const char* err_desc = "polling_island_add_fds"; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 351 | |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 352 | #ifdef GRPC_TSAN |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 353 | /* See the definition of g_epoll_sync for more context */ |
Sree Kuchibhotla | 0224dcc | 2016-06-22 18:04:00 -0700 | [diff] [blame] | 354 | gpr_atm_rel_store(&g_epoll_sync, (gpr_atm)0); |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 355 | #endif /* defined(GRPC_TSAN) */ |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 356 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 357 | for (i = 0; i < fd_count; i++) { |
Noah Eisen | be82e64 | 2018-02-09 09:16:55 -0800 | [diff] [blame] | 358 | ev.events = static_cast<uint32_t>(EPOLLIN | EPOLLOUT | EPOLLET); |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 359 | /* Use the least significant bit of ev.data.ptr to store track_err to avoid |
| 360 | * synchronization issues when accessing it after receiving an event */ |
| 361 | ev.data.ptr = reinterpret_cast<void*>(reinterpret_cast<intptr_t>(fds[i]) | |
| 362 | (fds[i]->track_err ? 1 : 0)); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 363 | 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] | 364 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 365 | if (err < 0) { |
| 366 | if (errno != EEXIST) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 367 | gpr_asprintf( |
| 368 | &err_msg, |
| 369 | "epoll_ctl (epoll_fd: %d) add fd: %d failed with error: %d (%s)", |
| 370 | pi->epoll_fd, fds[i]->fd, errno, strerror(errno)); |
| 371 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 372 | gpr_free(err_msg); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 373 | } |
| 374 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 375 | continue; |
| 376 | } |
| 377 | |
| 378 | if (pi->fd_cnt == pi->fd_capacity) { |
| 379 | pi->fd_capacity = GPR_MAX(pi->fd_capacity + 8, pi->fd_cnt * 3 / 2); |
Noah Eisen | 4d20a66 | 2018-02-09 09:34:04 -0800 | [diff] [blame] | 380 | pi->fds = static_cast<grpc_fd**>( |
| 381 | gpr_realloc(pi->fds, sizeof(grpc_fd*) * pi->fd_capacity)); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 382 | } |
| 383 | |
| 384 | pi->fds[pi->fd_cnt++] = fds[i]; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 385 | if (add_fd_refs) { |
| 386 | GRPC_FD_REF(fds[i], "polling_island"); |
| 387 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 388 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 389 | } |
| 390 | |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 391 | /* The caller is expected to hold pi->mu before calling this */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 392 | static void polling_island_add_wakeup_fd_locked(polling_island* pi, |
| 393 | grpc_wakeup_fd* wakeup_fd, |
| 394 | grpc_error** error) { |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 395 | struct epoll_event ev; |
| 396 | int err; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 397 | char* err_msg; |
| 398 | const char* err_desc = "polling_island_add_wakeup_fd"; |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 399 | |
Noah Eisen | be82e64 | 2018-02-09 09:16:55 -0800 | [diff] [blame] | 400 | ev.events = static_cast<uint32_t>(EPOLLIN | EPOLLET); |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 401 | ev.data.ptr = wakeup_fd; |
| 402 | err = epoll_ctl(pi->epoll_fd, EPOLL_CTL_ADD, |
| 403 | GRPC_WAKEUP_FD_GET_READ_FD(wakeup_fd), &ev); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 404 | if (err < 0 && errno != EEXIST) { |
| 405 | gpr_asprintf(&err_msg, |
| 406 | "epoll_ctl (epoll_fd: %d) add wakeup fd: %d failed with " |
| 407 | "error: %d (%s)", |
Craig Tiller | c357179 | 2017-05-02 12:33:38 -0700 | [diff] [blame] | 408 | pi->epoll_fd, GRPC_WAKEUP_FD_GET_READ_FD(wakeup_fd), errno, |
| 409 | strerror(errno)); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 410 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 411 | gpr_free(err_msg); |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 412 | } |
| 413 | } |
| 414 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 415 | /* The caller is expected to hold pi->mu lock before calling this function */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 416 | static void polling_island_remove_all_fds_locked(polling_island* pi, |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 417 | bool remove_fd_refs, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 418 | grpc_error** error) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 419 | int err; |
| 420 | size_t i; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 421 | char* err_msg; |
| 422 | const char* err_desc = "polling_island_remove_fds"; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 423 | |
| 424 | for (i = 0; i < pi->fd_cnt; i++) { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 425 | err = epoll_ctl(pi->epoll_fd, EPOLL_CTL_DEL, pi->fds[i]->fd, nullptr); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 426 | if (err < 0 && errno != ENOENT) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 427 | gpr_asprintf(&err_msg, |
| 428 | "epoll_ctl (epoll_fd: %d) delete fds[%zu]: %d failed with " |
| 429 | "error: %d (%s)", |
| 430 | pi->epoll_fd, i, pi->fds[i]->fd, errno, strerror(errno)); |
| 431 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 432 | gpr_free(err_msg); |
Sree Kuchibhotla | ad162ba | 2016-06-06 16:23:37 -0700 | [diff] [blame] | 433 | } |
| 434 | |
| 435 | if (remove_fd_refs) { |
| 436 | GRPC_FD_UNREF(pi->fds[i], "polling_island"); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 437 | } |
| 438 | } |
| 439 | |
| 440 | pi->fd_cnt = 0; |
| 441 | } |
| 442 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 443 | /* The caller is expected to hold pi->mu lock before calling this function */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 444 | 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] | 445 | bool is_fd_closed, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 446 | grpc_error** error) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 447 | int err; |
| 448 | size_t i; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 449 | char* err_msg; |
| 450 | const char* err_desc = "polling_island_remove_fd"; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 451 | |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 452 | /* If fd is already closed, then it would have been automatically been removed |
| 453 | from the epoll set */ |
| 454 | if (!is_fd_closed) { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 455 | err = epoll_ctl(pi->epoll_fd, EPOLL_CTL_DEL, fd->fd, nullptr); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 456 | if (err < 0 && errno != ENOENT) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 457 | gpr_asprintf( |
| 458 | &err_msg, |
| 459 | "epoll_ctl (epoll_fd: %d) del fd: %d failed with error: %d (%s)", |
| 460 | pi->epoll_fd, fd->fd, errno, strerror(errno)); |
| 461 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 462 | gpr_free(err_msg); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 463 | } |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 464 | } |
| 465 | |
| 466 | for (i = 0; i < pi->fd_cnt; i++) { |
| 467 | if (pi->fds[i] == fd) { |
| 468 | pi->fds[i] = pi->fds[--pi->fd_cnt]; |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 469 | GRPC_FD_UNREF(fd, "polling_island"); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 470 | break; |
| 471 | } |
| 472 | } |
| 473 | } |
| 474 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 475 | /* Might return NULL in case of an error */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 476 | static polling_island* polling_island_create(grpc_fd* initial_fd, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 477 | grpc_error** error) { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 478 | polling_island* pi = nullptr; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 479 | const char* err_desc = "polling_island_create"; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 480 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 481 | *error = GRPC_ERROR_NONE; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 482 | |
Noah Eisen | be82e64 | 2018-02-09 09:16:55 -0800 | [diff] [blame] | 483 | pi = static_cast<polling_island*>(gpr_malloc(sizeof(*pi))); |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 484 | gpr_mu_init(&pi->mu); |
| 485 | pi->fd_cnt = 0; |
| 486 | pi->fd_capacity = 0; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 487 | pi->fds = nullptr; |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 488 | pi->epoll_fd = -1; |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 489 | |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 490 | gpr_atm_rel_store(&pi->ref_count, 0); |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 491 | gpr_atm_rel_store(&pi->poller_count, 0); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 492 | gpr_atm_rel_store(&pi->merged_to, (gpr_atm) nullptr); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 493 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 494 | pi->epoll_fd = epoll_create1(EPOLL_CLOEXEC); |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 495 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 496 | if (pi->epoll_fd < 0) { |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 497 | append_error(error, GRPC_OS_ERROR(errno, "epoll_create1"), err_desc); |
| 498 | goto done; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 499 | } |
| 500 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 501 | if (initial_fd != nullptr) { |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 502 | polling_island_add_fds_locked(pi, &initial_fd, 1, true, error); |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 503 | } |
| 504 | |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 505 | done: |
| 506 | if (*error != GRPC_ERROR_NONE) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 507 | polling_island_delete(pi); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 508 | pi = nullptr; |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 509 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 510 | return pi; |
| 511 | } |
| 512 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 513 | static void polling_island_delete(polling_island* pi) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 514 | GPR_ASSERT(pi->fd_cnt == 0); |
| 515 | |
Craig Tiller | 0a06cd7 | 2016-07-14 13:21:24 -0700 | [diff] [blame] | 516 | if (pi->epoll_fd >= 0) { |
| 517 | close(pi->epoll_fd); |
| 518 | } |
Craig Tiller | b39307d | 2016-06-30 15:39:13 -0700 | [diff] [blame] | 519 | gpr_mu_destroy(&pi->mu); |
| 520 | gpr_free(pi->fds); |
| 521 | gpr_free(pi); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 522 | } |
| 523 | |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 524 | /* Attempts to gets the last polling island in the linked list (liked by the |
| 525 | * 'merged_to' field). Since this does not lock the polling island, there are no |
| 526 | * guarantees that the island returned is the last island */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 527 | static polling_island* polling_island_maybe_get_latest(polling_island* pi) { |
| 528 | polling_island* next = (polling_island*)gpr_atm_acq_load(&pi->merged_to); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 529 | while (next != nullptr) { |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 530 | pi = next; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 531 | next = (polling_island*)gpr_atm_acq_load(&pi->merged_to); |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 532 | } |
| 533 | |
| 534 | return pi; |
| 535 | } |
| 536 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 537 | /* 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] | 538 | 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] | 539 | returned polling island's mu. |
| 540 | Usage: To lock/unlock polling island "pi", do the following: |
| 541 | polling_island *pi_latest = polling_island_lock(pi); |
| 542 | ... |
| 543 | ... critical section .. |
| 544 | ... |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 545 | gpr_mu_unlock(&pi_latest->mu); // NOTE: use pi_latest->mu. NOT pi->mu */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 546 | static polling_island* polling_island_lock(polling_island* pi) { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 547 | polling_island* next = nullptr; |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 548 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 549 | while (true) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 550 | next = (polling_island*)gpr_atm_acq_load(&pi->merged_to); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 551 | if (next == nullptr) { |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 552 | /* Looks like 'pi' is the last node in the linked list but unless we check |
| 553 | this by holding the pi->mu lock, we cannot be sure (i.e without the |
| 554 | pi->mu lock, we don't prevent island merges). |
| 555 | 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] | 556 | gpr_mu_lock(&pi->mu); |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 557 | next = (polling_island*)gpr_atm_acq_load(&pi->merged_to); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 558 | if (next == nullptr) { |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 559 | /* 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] | 560 | break; |
| 561 | } |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 562 | |
| 563 | /* pi->merged_to is not NULL i.e pi isn't the last node anymore. pi->mu |
| 564 | * isn't the lock we are interested in. Continue traversing the list */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 565 | gpr_mu_unlock(&pi->mu); |
| 566 | } |
| 567 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 568 | pi = next; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 569 | } |
| 570 | |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 571 | return pi; |
| 572 | } |
| 573 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 574 | /* Gets the lock on the *latest* polling islands in the linked lists pointed by |
| 575 | *p and *q (and also updates *p and *q to point to the latest polling islands) |
| 576 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 577 | This function is needed because calling the following block of code to obtain |
| 578 | locks on polling islands (*p and *q) is prone to deadlocks. |
| 579 | { |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 580 | polling_island_lock(*p, true); |
| 581 | polling_island_lock(*q, true); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 582 | } |
| 583 | |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 584 | Usage/example: |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 585 | polling_island *p1; |
| 586 | polling_island *p2; |
| 587 | .. |
| 588 | polling_island_lock_pair(&p1, &p2); |
| 589 | .. |
| 590 | .. Critical section with both p1 and p2 locked |
| 591 | .. |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 592 | // Release locks: Always call polling_island_unlock_pair() to release locks |
| 593 | polling_island_unlock_pair(p1, p2); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 594 | */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 595 | static void polling_island_lock_pair(polling_island** p, polling_island** q) { |
| 596 | polling_island* pi_1 = *p; |
| 597 | polling_island* pi_2 = *q; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 598 | polling_island* next_1 = nullptr; |
| 599 | polling_island* next_2 = nullptr; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 600 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 601 | /* The algorithm is simple: |
| 602 | - Go to the last polling islands in the linked lists *pi_1 and *pi_2 (and |
| 603 | keep updating pi_1 and pi_2) |
| 604 | - Then obtain locks on the islands by following a lock order rule of |
| 605 | locking polling_island with lower address first |
| 606 | Special case: Before obtaining the locks, check if pi_1 and pi_2 are |
| 607 | pointing to the same island. If that is the case, we can just call |
| 608 | polling_island_lock() |
| 609 | - After obtaining both the locks, double check that the polling islands |
| 610 | are still the last polling islands in their respective linked lists |
| 611 | (this is because there might have been polling island merges before |
| 612 | we got the lock) |
| 613 | - If the polling islands are the last islands, we are done. If not, |
| 614 | release the locks and continue the process from the first step */ |
| 615 | while (true) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 616 | next_1 = (polling_island*)gpr_atm_acq_load(&pi_1->merged_to); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 617 | while (next_1 != nullptr) { |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 618 | pi_1 = next_1; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 619 | next_1 = (polling_island*)gpr_atm_acq_load(&pi_1->merged_to); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 620 | } |
| 621 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 622 | next_2 = (polling_island*)gpr_atm_acq_load(&pi_2->merged_to); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 623 | while (next_2 != nullptr) { |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 624 | pi_2 = next_2; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 625 | next_2 = (polling_island*)gpr_atm_acq_load(&pi_2->merged_to); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 626 | } |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 627 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 628 | if (pi_1 == pi_2) { |
| 629 | pi_1 = pi_2 = polling_island_lock(pi_1); |
| 630 | break; |
| 631 | } |
| 632 | |
| 633 | if (pi_1 < pi_2) { |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 634 | gpr_mu_lock(&pi_1->mu); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 635 | gpr_mu_lock(&pi_2->mu); |
| 636 | } else { |
| 637 | gpr_mu_lock(&pi_2->mu); |
| 638 | gpr_mu_lock(&pi_1->mu); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 639 | } |
| 640 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 641 | next_1 = (polling_island*)gpr_atm_acq_load(&pi_1->merged_to); |
| 642 | next_2 = (polling_island*)gpr_atm_acq_load(&pi_2->merged_to); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 643 | if (next_1 == nullptr && next_2 == nullptr) { |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 644 | break; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 645 | } |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 646 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 647 | gpr_mu_unlock(&pi_1->mu); |
| 648 | gpr_mu_unlock(&pi_2->mu); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 649 | } |
| 650 | |
| 651 | *p = pi_1; |
| 652 | *q = pi_2; |
| 653 | } |
| 654 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 655 | static void polling_island_unlock_pair(polling_island* p, polling_island* q) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 656 | if (p == q) { |
| 657 | gpr_mu_unlock(&p->mu); |
| 658 | } else { |
| 659 | gpr_mu_unlock(&p->mu); |
| 660 | gpr_mu_unlock(&q->mu); |
| 661 | } |
| 662 | } |
| 663 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 664 | static polling_island* polling_island_merge(polling_island* p, |
| 665 | polling_island* q, |
| 666 | grpc_error** error) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 667 | /* Get locks on both the polling islands */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 668 | polling_island_lock_pair(&p, &q); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 669 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 670 | if (p != q) { |
| 671 | /* Make sure that p points to the polling island with fewer fds than q */ |
| 672 | if (p->fd_cnt > q->fd_cnt) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 673 | GPR_SWAP(polling_island*, p, q); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 674 | } |
| 675 | |
| 676 | /* Merge p with q i.e move all the fds from p (The one with fewer fds) to q |
| 677 | Note that the refcounts on the fds being moved will not change here. |
| 678 | This is why the last param in the following two functions is 'false') */ |
| 679 | polling_island_add_fds_locked(q, p->fds, p->fd_cnt, false, error); |
| 680 | polling_island_remove_all_fds_locked(p, false, error); |
| 681 | |
| 682 | /* Wakeup all the pollers (if any) on p so that they pickup this change */ |
| 683 | polling_island_add_wakeup_fd_locked(p, &polling_island_wakeup_fd, error); |
| 684 | |
| 685 | /* Add the 'merged_to' link from p --> q */ |
| 686 | gpr_atm_rel_store(&p->merged_to, (gpr_atm)q); |
| 687 | 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] | 688 | } |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 689 | /* else if p == q, nothing needs to be done */ |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 690 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 691 | polling_island_unlock_pair(p, q); |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 692 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 693 | /* Return the merged polling island (Note that no merge would have happened |
| 694 | if p == q which is ok) */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 695 | return q; |
Sree Kuchibhotla | 9442bab | 2016-05-20 17:54:06 -0700 | [diff] [blame] | 696 | } |
| 697 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 698 | static grpc_error* polling_island_global_init() { |
| 699 | grpc_error* error = GRPC_ERROR_NONE; |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 700 | |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 701 | error = grpc_wakeup_fd_init(&polling_island_wakeup_fd); |
| 702 | if (error == GRPC_ERROR_NONE) { |
| 703 | error = grpc_wakeup_fd_wakeup(&polling_island_wakeup_fd); |
| 704 | } |
| 705 | |
| 706 | return error; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 707 | } |
| 708 | |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 709 | static void polling_island_global_shutdown() { |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 710 | grpc_wakeup_fd_destroy(&polling_island_wakeup_fd); |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 711 | } |
| 712 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 713 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 714 | * Fd Definitions |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 715 | */ |
| 716 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 717 | /* 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] | 718 | * but instead so that implementations with multiple threads in (for example) |
| 719 | * epoll_wait deal with the race between pollset removal and incoming poll |
| 720 | * notifications. |
| 721 | * |
| 722 | * The problem is that the poller ultimately holds a reference to this |
| 723 | * object, so it is very difficult to know when is safe to free it, at least |
| 724 | * without some expensive synchronization. |
| 725 | * |
| 726 | * If we keep the object freelisted, in the worst case losing this race just |
| 727 | * becomes a spurious read notification on a reused fd. |
| 728 | */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 729 | |
| 730 | /* The alarm system needs to be able to wakeup 'some poller' sometimes |
| 731 | * (specifically when a new alarm needs to be triggered earlier than the next |
| 732 | * alarm 'epoch'). This wakeup_fd gives us something to alert on when such a |
| 733 | * case occurs. */ |
Sree Kuchibhotla | 9bc3d2d | 2016-06-06 10:27:56 -0700 | [diff] [blame] | 734 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 735 | static grpc_fd* fd_freelist = nullptr; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 736 | static gpr_mu fd_freelist_mu; |
| 737 | |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 738 | #ifndef NDEBUG |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 739 | #define REF_BY(fd, n, reason) ref_by(fd, n, reason, __FILE__, __LINE__) |
| 740 | #define UNREF_BY(fd, n, reason) unref_by(fd, n, reason, __FILE__, __LINE__) |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 741 | static void ref_by(grpc_fd* fd, int n, const char* reason, const char* file, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 742 | int line) { |
ncteisen | 9ffb149 | 2017-11-10 14:00:49 -0800 | [diff] [blame] | 743 | if (grpc_trace_fd_refcount.enabled()) { |
ncteisen | 973863d | 2017-06-12 10:28:50 -0700 | [diff] [blame] | 744 | gpr_log(GPR_DEBUG, |
| 745 | "FD %d %p ref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]", |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 746 | fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst), |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 747 | gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line); |
| 748 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 749 | #else |
| 750 | #define REF_BY(fd, n, reason) ref_by(fd, n) |
| 751 | #define UNREF_BY(fd, n, reason) unref_by(fd, n) |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 752 | static void ref_by(grpc_fd* fd, int n) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 753 | #endif |
| 754 | GPR_ASSERT(gpr_atm_no_barrier_fetch_add(&fd->refst, n) > 0); |
| 755 | } |
| 756 | |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 757 | #ifndef NDEBUG |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 758 | static void unref_by(grpc_fd* fd, int n, const char* reason, const char* file, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 759 | int line) { |
ncteisen | 9ffb149 | 2017-11-10 14:00:49 -0800 | [diff] [blame] | 760 | if (grpc_trace_fd_refcount.enabled()) { |
ncteisen | 973863d | 2017-06-12 10:28:50 -0700 | [diff] [blame] | 761 | gpr_log(GPR_DEBUG, |
| 762 | "FD %d %p unref %d %" PRIdPTR " -> %" PRIdPTR " [%s; %s:%d]", |
ncteisen | 3ac64f8 | 2017-06-19 17:35:44 -0700 | [diff] [blame] | 763 | fd->fd, fd, n, gpr_atm_no_barrier_load(&fd->refst), |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 764 | gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line); |
| 765 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 766 | #else |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 767 | static void unref_by(grpc_fd* fd, int n) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 768 | #endif |
Noah Eisen | 264879f | 2017-06-20 17:14:47 -0700 | [diff] [blame] | 769 | gpr_atm old = gpr_atm_full_fetch_add(&fd->refst, -n); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 770 | if (old == n) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 771 | /* Add the fd to the freelist */ |
| 772 | gpr_mu_lock(&fd_freelist_mu); |
| 773 | fd->freelist_next = fd_freelist; |
| 774 | fd_freelist = fd; |
| 775 | grpc_iomgr_unregister_object(&fd->iomgr_object); |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 776 | |
yang-g | ed49fe5 | 2017-11-20 13:49:54 -0800 | [diff] [blame] | 777 | fd->read_closure->DestroyEvent(); |
| 778 | fd->write_closure->DestroyEvent(); |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 779 | fd->error_closure->DestroyEvent(); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 780 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 781 | gpr_mu_unlock(&fd_freelist_mu); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 782 | } else { |
| 783 | GPR_ASSERT(old > n); |
| 784 | } |
| 785 | } |
| 786 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 787 | /* Increment refcount by two to avoid changing the orphan bit */ |
ncteisen | d39010e | 2017-06-08 17:08:07 -0700 | [diff] [blame] | 788 | #ifndef NDEBUG |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 789 | static void fd_ref(grpc_fd* fd, const char* reason, const char* file, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 790 | int line) { |
| 791 | ref_by(fd, 2, reason, file, line); |
| 792 | } |
| 793 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 794 | static void fd_unref(grpc_fd* fd, const char* reason, const char* file, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 795 | int line) { |
| 796 | unref_by(fd, 2, reason, file, line); |
| 797 | } |
| 798 | #else |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 799 | static void fd_ref(grpc_fd* fd) { ref_by(fd, 2); } |
| 800 | static void fd_unref(grpc_fd* fd) { unref_by(fd, 2); } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 801 | #endif |
| 802 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 803 | static void fd_global_init(void) { gpr_mu_init(&fd_freelist_mu); } |
| 804 | |
| 805 | static void fd_global_shutdown(void) { |
| 806 | gpr_mu_lock(&fd_freelist_mu); |
| 807 | gpr_mu_unlock(&fd_freelist_mu); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 808 | while (fd_freelist != nullptr) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 809 | grpc_fd* fd = fd_freelist; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 810 | fd_freelist = fd_freelist->freelist_next; |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 811 | gpr_mu_destroy(&fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 812 | gpr_free(fd); |
| 813 | } |
| 814 | gpr_mu_destroy(&fd_freelist_mu); |
| 815 | } |
| 816 | |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 817 | static grpc_fd* fd_create(int fd, const char* name, bool track_err) { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 818 | grpc_fd* new_fd = nullptr; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 819 | |
| 820 | gpr_mu_lock(&fd_freelist_mu); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 821 | if (fd_freelist != nullptr) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 822 | new_fd = fd_freelist; |
| 823 | fd_freelist = fd_freelist->freelist_next; |
| 824 | } |
| 825 | gpr_mu_unlock(&fd_freelist_mu); |
| 826 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 827 | if (new_fd == nullptr) { |
Noah Eisen | be82e64 | 2018-02-09 09:16:55 -0800 | [diff] [blame] | 828 | new_fd = static_cast<grpc_fd*>(gpr_malloc(sizeof(grpc_fd))); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 829 | gpr_mu_init(&new_fd->po.mu); |
yang-g | 26521b3 | 2017-11-17 17:15:37 -0800 | [diff] [blame] | 830 | new_fd->read_closure.Init(); |
| 831 | new_fd->write_closure.Init(); |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 832 | new_fd->error_closure.Init(); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 833 | } |
| 834 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 835 | /* Note: It is not really needed to get the new_fd->po.mu lock here. If this |
| 836 | * is a newly created fd (or an fd we got from the freelist), no one else |
| 837 | * would be holding a lock to it anyway. */ |
| 838 | gpr_mu_lock(&new_fd->po.mu); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 839 | new_fd->po.pi = nullptr; |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame] | 840 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 841 | new_fd->po.obj_type = POLL_OBJ_FD; |
| 842 | #endif |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 843 | |
Sree Kuchibhotla | 0224dcc | 2016-06-22 18:04:00 -0700 | [diff] [blame] | 844 | gpr_atm_rel_store(&new_fd->refst, (gpr_atm)1); |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 845 | new_fd->fd = fd; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 846 | new_fd->orphaned = false; |
yang-g | ed49fe5 | 2017-11-20 13:49:54 -0800 | [diff] [blame] | 847 | new_fd->read_closure->InitEvent(); |
| 848 | new_fd->write_closure->InitEvent(); |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 849 | new_fd->error_closure->InitEvent(); |
| 850 | new_fd->track_err = track_err; |
Sree Kuchibhotla | 61fe094 | 2017-02-14 12:26:56 -0800 | [diff] [blame] | 851 | 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] | 852 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 853 | new_fd->freelist_next = nullptr; |
| 854 | new_fd->on_done_closure = nullptr; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 855 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 856 | gpr_mu_unlock(&new_fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 857 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 858 | char* fd_name; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 859 | gpr_asprintf(&fd_name, "%s fd=%d", name, fd); |
| 860 | grpc_iomgr_register_object(&new_fd->iomgr_object, fd_name); |
Sree Kuchibhotla | 6a29545 | 2016-06-23 15:53:10 -0700 | [diff] [blame] | 861 | gpr_free(fd_name); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 862 | return new_fd; |
| 863 | } |
| 864 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 865 | static int fd_wrapped_fd(grpc_fd* fd) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 866 | int ret_fd = -1; |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 867 | gpr_mu_lock(&fd->po.mu); |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 868 | if (!fd->orphaned) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 869 | ret_fd = fd->fd; |
| 870 | } |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 871 | gpr_mu_unlock(&fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 872 | |
| 873 | return ret_fd; |
| 874 | } |
| 875 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 876 | static void fd_orphan(grpc_fd* fd, grpc_closure* on_done, int* release_fd, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 877 | bool already_closed, const char* reason) { |
| 878 | grpc_error* error = GRPC_ERROR_NONE; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 879 | polling_island* unref_pi = nullptr; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 880 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 881 | gpr_mu_lock(&fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 882 | fd->on_done_closure = on_done; |
| 883 | |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 884 | /* Remove the active status but keep referenced. We want this grpc_fd struct |
| 885 | to be alive (and not added to freelist) until the end of this function */ |
| 886 | REF_BY(fd, 1, reason); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 887 | |
| 888 | /* Remove the fd from the polling island: |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 889 | - 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] | 890 | linked list pointed by fd->po.pi). This is the island that |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 891 | would actually contain the fd |
| 892 | - Remove the fd from the latest polling island |
| 893 | - Unlock the latest polling island |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 894 | - 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] | 895 | before doing this.) */ |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 896 | if (fd->po.pi != nullptr) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 897 | polling_island* pi_latest = polling_island_lock(fd->po.pi); |
Yuchen Zeng | d40a7ae | 2017-07-12 15:59:56 -0700 | [diff] [blame] | 898 | polling_island_remove_fd_locked(pi_latest, fd, already_closed, &error); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 899 | gpr_mu_unlock(&pi_latest->mu); |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 900 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 901 | unref_pi = fd->po.pi; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 902 | fd->po.pi = nullptr; |
Sree Kuchibhotla | 88ee12f | 2016-06-03 19:26:48 -0700 | [diff] [blame] | 903 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 904 | |
Yuchen Zeng | 5b48dea | 2017-07-12 19:00:35 -0700 | [diff] [blame] | 905 | /* If release_fd is not NULL, we should be relinquishing control of the file |
| 906 | descriptor fd->fd (but we still own the grpc_fd structure). */ |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 907 | if (release_fd != nullptr) { |
Yuchen Zeng | 5b48dea | 2017-07-12 19:00:35 -0700 | [diff] [blame] | 908 | *release_fd = fd->fd; |
| 909 | } else { |
| 910 | close(fd->fd); |
| 911 | } |
| 912 | |
| 913 | fd->orphaned = true; |
| 914 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 915 | GRPC_CLOSURE_SCHED(fd->on_done_closure, GRPC_ERROR_REF(error)); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 916 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 917 | gpr_mu_unlock(&fd->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 918 | UNREF_BY(fd, 2, reason); /* Drop the reference */ |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 919 | if (unref_pi != nullptr) { |
Craig Tiller | 0a06cd7 | 2016-07-14 13:21:24 -0700 | [diff] [blame] | 920 | /* Unref stale polling island here, outside the fd lock above. |
| 921 | The polling island owns a workqueue which owns an fd, and unreffing |
| 922 | inside the lock can cause an eventual lock loop that makes TSAN very |
| 923 | unhappy. */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 924 | PI_UNREF(unref_pi, "fd_orphan"); |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 925 | } |
Yuchen Zeng | 4ebace7 | 2017-06-05 17:24:06 -0700 | [diff] [blame] | 926 | if (error != GRPC_ERROR_NONE) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 927 | const char* msg = grpc_error_string(error); |
Yuchen Zeng | 4ebace7 | 2017-06-05 17:24:06 -0700 | [diff] [blame] | 928 | gpr_log(GPR_DEBUG, "fd_orphan: %s", msg); |
| 929 | } |
Yuchen Zeng | a0399f2 | 2016-08-04 17:52:53 -0700 | [diff] [blame] | 930 | GRPC_ERROR_UNREF(error); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 931 | } |
| 932 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 933 | static grpc_pollset* fd_get_read_notifier_pollset(grpc_fd* fd) { |
Sree Kuchibhotla | fb7ced6 | 2017-02-15 18:31:57 -0800 | [diff] [blame] | 934 | gpr_atm notifier = gpr_atm_acq_load(&fd->read_notifier_pollset); |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 935 | return (grpc_pollset*)notifier; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 936 | } |
| 937 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 938 | static bool fd_is_shutdown(grpc_fd* fd) { |
Craig Tiller | fbf61bb | 2017-11-08 11:50:14 -0800 | [diff] [blame] | 939 | return fd->read_closure->IsShutdown(); |
Sree Kuchibhotla | 24b6eae | 2016-06-21 18:01:14 -0700 | [diff] [blame] | 940 | } |
| 941 | |
Sree Kuchibhotla | 0100b2f | 2016-06-21 17:38:13 -0700 | [diff] [blame] | 942 | /* Might be called multiple times */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 943 | static void fd_shutdown(grpc_fd* fd, grpc_error* why) { |
| 944 | if (fd->read_closure->SetShutdown(GRPC_ERROR_REF(why))) { |
Sree Kuchibhotla | 0100b2f | 2016-06-21 17:38:13 -0700 | [diff] [blame] | 945 | shutdown(fd->fd, SHUT_RDWR); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 946 | fd->write_closure->SetShutdown(GRPC_ERROR_REF(why)); |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 947 | fd->error_closure->SetShutdown(GRPC_ERROR_REF(why)); |
Sree Kuchibhotla | 0100b2f | 2016-06-21 17:38:13 -0700 | [diff] [blame] | 948 | } |
Craig Tiller | 376887d | 2017-04-06 08:27:03 -0700 | [diff] [blame] | 949 | GRPC_ERROR_UNREF(why); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 950 | } |
| 951 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 952 | static void fd_notify_on_read(grpc_fd* fd, grpc_closure* closure) { |
| 953 | fd->read_closure->NotifyOn(closure); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 954 | } |
| 955 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 956 | static void fd_notify_on_write(grpc_fd* fd, grpc_closure* closure) { |
| 957 | fd->write_closure->NotifyOn(closure); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 958 | } |
| 959 | |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 960 | static void fd_notify_on_error(grpc_fd* fd, grpc_closure* closure) { |
| 961 | fd->error_closure->NotifyOn(closure); |
| 962 | } |
| 963 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 964 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 965 | * Pollset Definitions |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 966 | */ |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 967 | GPR_TLS_DECL(g_current_thread_pollset); |
| 968 | GPR_TLS_DECL(g_current_thread_worker); |
Craig Tiller | 1919699 | 2016-06-27 18:45:56 -0700 | [diff] [blame] | 969 | static __thread bool g_initialized_sigmask; |
| 970 | static __thread sigset_t g_orig_sigmask; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 971 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 972 | static void sig_handler(int sig_num) { |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 973 | #ifdef GRPC_EPOLL_DEBUG |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 974 | gpr_log(GPR_INFO, "Received signal %d", sig_num); |
Sree Kuchibhotla | 9bc3d2d | 2016-06-06 10:27:56 -0700 | [diff] [blame] | 975 | #endif |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 976 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 977 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 978 | static void poller_kick_init() { signal(grpc_wakeup_signal, sig_handler); } |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 979 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 980 | /* Global state management */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 981 | static grpc_error* pollset_global_init(void) { |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 982 | gpr_tls_init(&g_current_thread_pollset); |
| 983 | gpr_tls_init(&g_current_thread_worker); |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 984 | poller_kick_init(); |
Craig Tiller | c357179 | 2017-05-02 12:33:38 -0700 | [diff] [blame] | 985 | return GRPC_ERROR_NONE; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 986 | } |
| 987 | |
| 988 | static void pollset_global_shutdown(void) { |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 989 | gpr_tls_destroy(&g_current_thread_pollset); |
| 990 | gpr_tls_destroy(&g_current_thread_worker); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 991 | } |
| 992 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 993 | static grpc_error* pollset_worker_kick(grpc_pollset_worker* worker) { |
| 994 | grpc_error* err = GRPC_ERROR_NONE; |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 995 | |
| 996 | /* Kick the worker only if it was not already kicked */ |
Noah Eisen | 4d20a66 | 2018-02-09 09:34:04 -0800 | [diff] [blame] | 997 | if (gpr_atm_no_barrier_cas(&worker->is_kicked, static_cast<gpr_atm>(0), |
| 998 | static_cast<gpr_atm>(1))) { |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 999 | GRPC_POLLING_TRACE( |
| 1000 | "pollset_worker_kick: Kicking worker: %p (thread id: %ld)", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1001 | (void*)worker, (long int)worker->pt_id); |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1002 | int err_num = pthread_kill(worker->pt_id, grpc_wakeup_signal); |
| 1003 | if (err_num != 0) { |
| 1004 | err = GRPC_OS_ERROR(err_num, "pthread_kill"); |
| 1005 | } |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1006 | } |
| 1007 | return err; |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 1008 | } |
| 1009 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1010 | /* Return 1 if the pollset has active threads in pollset_work (pollset must |
| 1011 | * be locked) */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1012 | static int pollset_has_workers(grpc_pollset* p) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1013 | return p->root_worker.next != &p->root_worker; |
| 1014 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1015 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1016 | static void remove_worker(grpc_pollset* p, grpc_pollset_worker* worker) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1017 | worker->prev->next = worker->next; |
| 1018 | worker->next->prev = worker->prev; |
| 1019 | } |
| 1020 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1021 | static grpc_pollset_worker* pop_front_worker(grpc_pollset* p) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1022 | if (pollset_has_workers(p)) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1023 | grpc_pollset_worker* w = p->root_worker.next; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1024 | remove_worker(p, w); |
| 1025 | return w; |
| 1026 | } else { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1027 | return nullptr; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1028 | } |
| 1029 | } |
| 1030 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1031 | static void push_back_worker(grpc_pollset* p, grpc_pollset_worker* worker) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1032 | worker->next = &p->root_worker; |
| 1033 | worker->prev = worker->next->prev; |
| 1034 | worker->prev->next = worker->next->prev = worker; |
| 1035 | } |
| 1036 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1037 | static void push_front_worker(grpc_pollset* p, grpc_pollset_worker* worker) { |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1038 | worker->prev = &p->root_worker; |
| 1039 | worker->next = worker->prev->next; |
| 1040 | worker->prev->next = worker->next->prev = worker; |
| 1041 | } |
| 1042 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1043 | /* p->mu must be held before calling this function */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1044 | static grpc_error* pollset_kick(grpc_pollset* p, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1045 | grpc_pollset_worker* specific_worker) { |
yang-g | ce1cfea | 2018-01-31 15:59:50 -0800 | [diff] [blame] | 1046 | GPR_TIMER_SCOPE("pollset_kick", 0); |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1047 | grpc_error* error = GRPC_ERROR_NONE; |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1048 | GRPC_STATS_INC_POLLSET_KICK(); |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1049 | const char* err_desc = "Kick Failure"; |
| 1050 | grpc_pollset_worker* worker = specific_worker; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1051 | if (worker != nullptr) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1052 | if (worker == GRPC_POLLSET_KICK_BROADCAST) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1053 | if (pollset_has_workers(p)) { |
yang-g | ce1cfea | 2018-01-31 15:59:50 -0800 | [diff] [blame] | 1054 | GPR_TIMER_SCOPE("pollset_kick.broadcast", 0); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1055 | for (worker = p->root_worker.next; worker != &p->root_worker; |
| 1056 | worker = worker->next) { |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1057 | if (gpr_tls_get(&g_current_thread_worker) != (intptr_t)worker) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1058 | append_error(&error, pollset_worker_kick(worker), err_desc); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1059 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1060 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1061 | } else { |
| 1062 | p->kicked_without_pollers = true; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1063 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1064 | } else { |
| 1065 | GPR_TIMER_MARK("kicked_specifically", 0); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1066 | if (gpr_tls_get(&g_current_thread_worker) != (intptr_t)worker) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1067 | append_error(&error, pollset_worker_kick(worker), err_desc); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1068 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1069 | } |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1070 | } else if (gpr_tls_get(&g_current_thread_pollset) != (intptr_t)p) { |
| 1071 | /* Since worker == NULL, it means that we can kick "any" worker on this |
| 1072 | pollset 'p'. If 'p' happens to be the same pollset this thread is |
| 1073 | currently polling (i.e in pollset_work() function), then there is no need |
| 1074 | to kick any other worker since the current thread can just absorb the |
| 1075 | kick. This is the reason why we enter this case only when |
| 1076 | g_current_thread_pollset is != p */ |
| 1077 | |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1078 | GPR_TIMER_MARK("kick_anonymous", 0); |
| 1079 | worker = pop_front_worker(p); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1080 | if (worker != nullptr) { |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1081 | GPR_TIMER_MARK("finally_kick", 0); |
| 1082 | push_back_worker(p, worker); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1083 | append_error(&error, pollset_worker_kick(worker), err_desc); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1084 | } else { |
| 1085 | GPR_TIMER_MARK("kicked_no_pollers", 0); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1086 | p->kicked_without_pollers = true; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1087 | } |
| 1088 | } |
| 1089 | |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1090 | GRPC_LOG_IF_ERROR("pollset_kick", GRPC_ERROR_REF(error)); |
| 1091 | return error; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1092 | } |
| 1093 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1094 | static void pollset_init(grpc_pollset* pollset, gpr_mu** mu) { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1095 | gpr_mu_init(&pollset->po.mu); |
| 1096 | *mu = &pollset->po.mu; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1097 | pollset->po.pi = nullptr; |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame] | 1098 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1099 | pollset->po.obj_type = POLL_OBJ_POLLSET; |
| 1100 | #endif |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1101 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1102 | pollset->root_worker.next = pollset->root_worker.prev = &pollset->root_worker; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1103 | pollset->kicked_without_pollers = false; |
| 1104 | |
| 1105 | pollset->shutting_down = false; |
| 1106 | pollset->finish_shutdown_called = false; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1107 | pollset->shutdown_done = nullptr; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1108 | } |
| 1109 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1110 | static int poll_deadline_to_millis_timeout(grpc_millis millis) { |
Craig Tiller | 2039779 | 2017-07-18 11:35:27 -0700 | [diff] [blame] | 1111 | if (millis == GRPC_MILLIS_INF_FUTURE) return -1; |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1112 | grpc_millis delta = millis - grpc_core::ExecCtx::Get()->Now(); |
Craig Tiller | 2039779 | 2017-07-18 11:35:27 -0700 | [diff] [blame] | 1113 | if (delta > INT_MAX) |
| 1114 | return INT_MAX; |
| 1115 | else if (delta < 0) |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1116 | return 0; |
Craig Tiller | 2039779 | 2017-07-18 11:35:27 -0700 | [diff] [blame] | 1117 | else |
Noah Eisen | be82e64 | 2018-02-09 09:16:55 -0800 | [diff] [blame] | 1118 | return static_cast<int>(delta); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1119 | } |
| 1120 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1121 | static void fd_become_readable(grpc_fd* fd, grpc_pollset* notifier) { |
| 1122 | fd->read_closure->SetReady(); |
Sree Kuchibhotla | 82d7341 | 2017-02-09 18:27:45 -0800 | [diff] [blame] | 1123 | |
Sree Kuchibhotla | 4db8c82 | 2017-02-12 17:07:31 -0800 | [diff] [blame] | 1124 | /* 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] | 1125 | different 'notifier's when an fd becomes readable and it is in two epoll |
| 1126 | sets (This can happen briefly during polling island merges). In such cases |
| 1127 | it does not really matter which notifer is set as the read_notifier_pollset |
| 1128 | (They would both point to the same polling island anyway) */ |
Sree Kuchibhotla | fb7ced6 | 2017-02-15 18:31:57 -0800 | [diff] [blame] | 1129 | /* Use release store to match with acquire load in fd_get_read_notifier */ |
| 1130 | gpr_atm_rel_store(&fd->read_notifier_pollset, (gpr_atm)notifier); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1131 | } |
| 1132 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1133 | static void fd_become_writable(grpc_fd* fd) { fd->write_closure->SetReady(); } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1134 | |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 1135 | static void fd_has_errors(grpc_fd* fd) { fd->error_closure->SetReady(); } |
| 1136 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1137 | static void pollset_release_polling_island(grpc_pollset* ps, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1138 | const char* reason) { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1139 | if (ps->po.pi != nullptr) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1140 | PI_UNREF(ps->po.pi, reason); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1141 | } |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1142 | ps->po.pi = nullptr; |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1143 | } |
| 1144 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1145 | static void finish_shutdown_locked(grpc_pollset* pollset) { |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1146 | /* The pollset cannot have any workers if we are at this stage */ |
| 1147 | GPR_ASSERT(!pollset_has_workers(pollset)); |
| 1148 | |
| 1149 | pollset->finish_shutdown_called = true; |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1150 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1151 | /* Release the ref and set pollset->po.pi to NULL */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1152 | pollset_release_polling_island(pollset, "ps_shutdown"); |
| 1153 | GRPC_CLOSURE_SCHED(pollset->shutdown_done, GRPC_ERROR_NONE); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1154 | } |
| 1155 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1156 | /* pollset->po.mu lock must be held by the caller before calling this */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1157 | static void pollset_shutdown(grpc_pollset* pollset, grpc_closure* closure) { |
yang-g | ce1cfea | 2018-01-31 15:59:50 -0800 | [diff] [blame] | 1158 | GPR_TIMER_SCOPE("pollset_shutdown", 0); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1159 | GPR_ASSERT(!pollset->shutting_down); |
| 1160 | pollset->shutting_down = true; |
| 1161 | pollset->shutdown_done = closure; |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1162 | pollset_kick(pollset, GRPC_POLLSET_KICK_BROADCAST); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1163 | |
| 1164 | /* If the pollset has any workers, we cannot call finish_shutdown_locked() |
| 1165 | because it would release the underlying polling island. In such a case, we |
| 1166 | let the last worker call finish_shutdown_locked() from pollset_work() */ |
| 1167 | if (!pollset_has_workers(pollset)) { |
| 1168 | GPR_ASSERT(!pollset->finish_shutdown_called); |
| 1169 | GPR_TIMER_MARK("pollset_shutdown.finish_shutdown_locked", 0); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1170 | finish_shutdown_locked(pollset); |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1171 | } |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 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 */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1177 | static void pollset_destroy(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() */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1184 | static void pollset_work_and_unlock(grpc_pollset* pollset, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1185 | grpc_pollset_worker* worker, int timeout_ms, |
| 1186 | sigset_t* sig_mask, grpc_error** error) { |
yang-g | ce1cfea | 2018-01-31 15:59:50 -0800 | [diff] [blame] | 1187 | GPR_TIMER_SCOPE("pollset_work_and_unlock", 0); |
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; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1191 | polling_island* pi = nullptr; |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -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 | |
| 1195 | /* 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] | 1196 | latest polling island pointed by pollset->po.pi |
Sree Kuchibhotla | 229533b1 | 2016-06-21 20:42:52 -0700 | [diff] [blame] | 1197 | |
| 1198 | Since epoll_fd is immutable, we can read it without obtaining the polling |
| 1199 | island lock. There is however a possibility that the polling island (from |
| 1200 | which we got the epoll_fd) got merged with another island while we are |
| 1201 | in this function. This is still okay because in such a case, we will wakeup |
| 1202 | 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] | 1203 | this function (i.e pollset_work_and_unlock()) is called */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1204 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1205 | if (pollset->po.pi == nullptr) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1206 | pollset->po.pi = polling_island_create(nullptr, error); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1207 | if (pollset->po.pi == nullptr) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1208 | return; /* Fatal error. We cannot continue */ |
| 1209 | } |
| 1210 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1211 | PI_ADD_REF(pollset->po.pi, "ps"); |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1212 | GRPC_POLLING_TRACE("pollset_work: pollset: %p created new pi: %p", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1213 | (void*)pollset, (void*)pollset->po.pi); |
Sree Kuchibhotla | 88ee12f | 2016-06-03 19:26:48 -0700 | [diff] [blame] | 1214 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1215 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1216 | pi = polling_island_maybe_get_latest(pollset->po.pi); |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 1217 | epoll_fd = pi->epoll_fd; |
| 1218 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1219 | /* Update the pollset->po.pi since the island being pointed by |
| 1220 | pollset->po.pi maybe older than the one pointed by pi) */ |
| 1221 | if (pollset->po.pi != pi) { |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1222 | /* Always do PI_ADD_REF before PI_UNREF because PI_UNREF may cause the |
| 1223 | polling island to be deleted */ |
| 1224 | PI_ADD_REF(pi, "ps"); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1225 | PI_UNREF(pollset->po.pi, "ps"); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1226 | pollset->po.pi = pi; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1227 | } |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 1228 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1229 | /* Add an extra ref so that the island does not get destroyed (which means |
| 1230 | the epoll_fd won't be closed) while we are are doing an epoll_wait() on the |
| 1231 | epoll_fd */ |
| 1232 | PI_ADD_REF(pi, "ps_work"); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1233 | gpr_mu_unlock(&pollset->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1234 | |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1235 | gpr_atm_no_barrier_fetch_add(&pi->poller_count, 1); |
| 1236 | g_current_thread_polling_island = pi; |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 1237 | |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1238 | GRPC_SCHEDULING_START_BLOCKING_REGION; |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1239 | GRPC_STATS_INC_SYSCALL_POLL(); |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1240 | ep_rv = |
| 1241 | epoll_pwait(epoll_fd, ep_ev, GRPC_EPOLL_MAX_EVENTS, timeout_ms, sig_mask); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1242 | GRPC_SCHEDULING_END_BLOCKING_REGION; |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1243 | if (ep_rv < 0) { |
| 1244 | if (errno != EINTR) { |
| 1245 | gpr_asprintf(&err_msg, |
| 1246 | "epoll_wait() epoll fd: %d failed with error: %d (%s)", |
| 1247 | epoll_fd, errno, strerror(errno)); |
| 1248 | append_error(error, GRPC_OS_ERROR(errno, err_msg), err_desc); |
| 1249 | } else { |
| 1250 | /* We were interrupted. Save an interation by doing a zero timeout |
| 1251 | epoll_wait to see if there are any other events of interest */ |
| 1252 | GRPC_POLLING_TRACE("pollset_work: pollset: %p, worker: %p received kick", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1253 | (void*)pollset, (void*)worker); |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1254 | 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] | 1255 | } |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1256 | } |
Sree Kuchibhotla | 79a6233 | 2016-06-04 14:01:03 -0700 | [diff] [blame] | 1257 | |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 1258 | #ifdef GRPC_TSAN |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1259 | /* See the definition of g_poll_sync for more details */ |
| 1260 | gpr_atm_acq_load(&g_epoll_sync); |
Sree Kuchibhotla | ad2c477 | 2016-06-13 19:06:54 -0700 | [diff] [blame] | 1261 | #endif /* defined(GRPC_TSAN) */ |
Sree Kuchibhotla | 41622a8 | 2016-06-13 16:43:14 -0700 | [diff] [blame] | 1262 | |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1263 | for (int i = 0; i < ep_rv; ++i) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1264 | void* data_ptr = ep_ev[i].data.ptr; |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1265 | if (data_ptr == &polling_island_wakeup_fd) { |
| 1266 | GRPC_POLLING_TRACE( |
| 1267 | "pollset_work: pollset: %p, worker: %p polling island (epoll_fd: " |
| 1268 | "%d) got merged", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1269 | (void*)pollset, (void*)worker, epoll_fd); |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1270 | /* This means that our polling island is merged with a different |
| 1271 | island. We do not have to do anything here since the subsequent call |
| 1272 | to the function pollset_work_and_unlock() will pick up the correct |
| 1273 | epoll_fd */ |
| 1274 | } else { |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 1275 | grpc_fd* fd = reinterpret_cast<grpc_fd*>( |
| 1276 | reinterpret_cast<intptr_t>(data_ptr) & ~static_cast<intptr_t>(1)); |
| 1277 | bool track_err = |
| 1278 | reinterpret_cast<intptr_t>(data_ptr) & ~static_cast<intptr_t>(1); |
| 1279 | bool cancel = (ep_ev[i].events & EPOLLHUP) != 0; |
| 1280 | bool error = (ep_ev[i].events & EPOLLERR) != 0; |
| 1281 | bool read_ev = (ep_ev[i].events & (EPOLLIN | EPOLLPRI)) != 0; |
| 1282 | bool write_ev = (ep_ev[i].events & EPOLLOUT) != 0; |
| 1283 | bool err_fallback = error && track_err; |
| 1284 | |
| 1285 | if (error && !err_fallback) { |
| 1286 | fd_has_errors(fd); |
| 1287 | } |
| 1288 | if (read_ev || cancel || err_fallback) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1289 | fd_become_readable(fd, pollset); |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1290 | } |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 1291 | if (write_ev || cancel || err_fallback) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1292 | fd_become_writable(fd); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1293 | } |
Sree Kuchibhotla | e5012ba | 2016-06-06 16:01:45 -0700 | [diff] [blame] | 1294 | } |
Craig Tiller | d8a3c04 | 2016-09-09 12:42:37 -0700 | [diff] [blame] | 1295 | } |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 1296 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1297 | g_current_thread_polling_island = nullptr; |
Craig Tiller | 61f96c1 | 2017-05-12 13:36:39 -0700 | [diff] [blame] | 1298 | gpr_atm_no_barrier_fetch_add(&pi->poller_count, -1); |
| 1299 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1300 | GPR_ASSERT(pi != nullptr); |
Sree Kuchibhotla | 24b1062 | 2016-06-08 15:20:17 -0700 | [diff] [blame] | 1301 | |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1302 | /* 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] | 1303 | 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] | 1304 | that we got before releasing the polling island lock). This is because |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1305 | pollset->po.pi pointer might get udpated in other parts of the |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1306 | code when there is an island merge while we are doing epoll_wait() above */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1307 | PI_UNREF(pi, "ps_work"); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1308 | } |
| 1309 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1310 | /* pollset->po.mu lock must be held by the caller before calling this. |
| 1311 | The function pollset_work() may temporarily release the lock (pollset->po.mu) |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1312 | during the course of its execution but it will always re-acquire the lock and |
| 1313 | ensure that it is held by the time the function returns */ |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1314 | static grpc_error* pollset_work(grpc_pollset* pollset, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1315 | grpc_pollset_worker** worker_hdl, |
Craig Tiller | 2039779 | 2017-07-18 11:35:27 -0700 | [diff] [blame] | 1316 | grpc_millis deadline) { |
yang-g | ce1cfea | 2018-01-31 15:59:50 -0800 | [diff] [blame] | 1317 | GPR_TIMER_SCOPE("pollset_work", 0); |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1318 | grpc_error* error = GRPC_ERROR_NONE; |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1319 | int timeout_ms = poll_deadline_to_millis_timeout(deadline); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1320 | |
| 1321 | sigset_t new_mask; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1322 | |
| 1323 | grpc_pollset_worker worker; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1324 | worker.next = worker.prev = nullptr; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1325 | worker.pt_id = pthread_self(); |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1326 | gpr_atm_no_barrier_store(&worker.is_kicked, (gpr_atm)0); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1327 | |
Craig Tiller | 557c88c | 2017-04-05 17:20:18 -0700 | [diff] [blame] | 1328 | if (worker_hdl) *worker_hdl = &worker; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1329 | |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1330 | gpr_tls_set(&g_current_thread_pollset, (intptr_t)pollset); |
| 1331 | gpr_tls_set(&g_current_thread_worker, (intptr_t)&worker); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1332 | |
| 1333 | if (pollset->kicked_without_pollers) { |
| 1334 | /* If the pollset was kicked without pollers, pretend that the current |
| 1335 | worker got the kick and skip polling. A kick indicates that there is some |
| 1336 | work that needs attention like an event on the completion queue or an |
| 1337 | alarm */ |
| 1338 | GPR_TIMER_MARK("pollset_work.kicked_without_pollers", 0); |
| 1339 | pollset->kicked_without_pollers = 0; |
| 1340 | } else if (!pollset->shutting_down) { |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1341 | /* 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] | 1342 | (i.e 'kicking') a worker in the pollset. A 'kick' is a way to inform the |
| 1343 | worker that there is some pending work that needs immediate attention |
| 1344 | (like an event on the completion queue, or a polling island merge that |
| 1345 | results in a new epoll-fd to wait on) and that the worker should not |
| 1346 | spend time waiting in epoll_pwait(). |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1347 | |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1348 | A worker can be kicked anytime from the point it is added to the pollset |
| 1349 | via push_front_worker() (or push_back_worker()) to the point it is |
| 1350 | removed via remove_worker(). |
| 1351 | If the worker is kicked before/during it calls epoll_pwait(), it should |
| 1352 | immediately exit from epoll_wait(). If the worker is kicked after it |
| 1353 | returns from epoll_wait(), then nothing really needs to be done. |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1354 | |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1355 | 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] | 1356 | times *except* when it is in epoll_pwait(). This way, the worker never |
| 1357 | misses acting on a kick */ |
| 1358 | |
Craig Tiller | 1919699 | 2016-06-27 18:45:56 -0700 | [diff] [blame] | 1359 | if (!g_initialized_sigmask) { |
| 1360 | sigemptyset(&new_mask); |
| 1361 | sigaddset(&new_mask, grpc_wakeup_signal); |
| 1362 | pthread_sigmask(SIG_BLOCK, &new_mask, &g_orig_sigmask); |
| 1363 | sigdelset(&g_orig_sigmask, grpc_wakeup_signal); |
| 1364 | g_initialized_sigmask = true; |
| 1365 | /* new_mask: The new thread mask which blocks 'grpc_wakeup_signal'. |
| 1366 | This is the mask used at all times *except during |
| 1367 | epoll_wait()*" |
| 1368 | g_orig_sigmask: The thread mask which allows 'grpc_wakeup_signal' and |
Craig Tiller | 510ff69 | 2016-06-27 20:31:49 -0700 | [diff] [blame] | 1369 | this is the mask to use *during epoll_wait()* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1370 | |
Craig Tiller | 1919699 | 2016-06-27 18:45:56 -0700 | [diff] [blame] | 1371 | 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] | 1372 | (i.e before it can be kicked) */ |
Craig Tiller | 1919699 | 2016-06-27 18:45:56 -0700 | [diff] [blame] | 1373 | } |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1374 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1375 | push_front_worker(pollset, &worker); /* Add worker to pollset */ |
| 1376 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1377 | pollset_work_and_unlock(pollset, &worker, timeout_ms, &g_orig_sigmask, |
| 1378 | &error); |
| 1379 | grpc_core::ExecCtx::Get()->Flush(); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1380 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1381 | gpr_mu_lock(&pollset->po.mu); |
Sree Kuchibhotla | 3421724 | 2016-06-29 00:19:07 -0700 | [diff] [blame] | 1382 | |
| 1383 | /* Note: There is no need to reset worker.is_kicked to 0 since we are no |
| 1384 | longer going to use this worker */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1385 | remove_worker(pollset, &worker); |
| 1386 | } |
| 1387 | |
| 1388 | /* If we are the last worker on the pollset (i.e pollset_has_workers() is |
| 1389 | false at this point) and the pollset is shutting down, we may have to |
| 1390 | finish the shutdown process by calling finish_shutdown_locked(). |
| 1391 | See pollset_shutdown() for more details. |
| 1392 | |
| 1393 | Note: Continuing to access pollset here is safe; it is the caller's |
| 1394 | responsibility to not destroy a pollset when it has outstanding calls to |
| 1395 | pollset_work() */ |
| 1396 | if (pollset->shutting_down && !pollset_has_workers(pollset) && |
| 1397 | !pollset->finish_shutdown_called) { |
| 1398 | GPR_TIMER_MARK("pollset_work.finish_shutdown_locked", 0); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1399 | finish_shutdown_locked(pollset); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1400 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1401 | gpr_mu_unlock(&pollset->po.mu); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1402 | grpc_core::ExecCtx::Get()->Flush(); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1403 | gpr_mu_lock(&pollset->po.mu); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1404 | } |
| 1405 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1406 | if (worker_hdl) *worker_hdl = nullptr; |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1407 | |
Sree Kuchibhotla | 8e4926c | 2016-06-08 20:33:19 -0700 | [diff] [blame] | 1408 | gpr_tls_set(&g_current_thread_pollset, (intptr_t)0); |
| 1409 | gpr_tls_set(&g_current_thread_worker, (intptr_t)0); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1410 | |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1411 | GRPC_LOG_IF_ERROR("pollset_work", GRPC_ERROR_REF(error)); |
| 1412 | return error; |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1413 | } |
| 1414 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1415 | static void add_poll_object(poll_obj* bag, poll_obj_type bag_type, |
| 1416 | poll_obj* item, poll_obj_type item_type) { |
yang-g | ce1cfea | 2018-01-31 15:59:50 -0800 | [diff] [blame] | 1417 | GPR_TIMER_SCOPE("add_poll_object", 0); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1418 | |
ncteisen | e9cd8a8 | 2017-06-29 06:03:52 -0400 | [diff] [blame] | 1419 | #ifndef NDEBUG |
Sree Kuchibhotla | a0749a6 | 2016-11-18 20:22:09 -0800 | [diff] [blame] | 1420 | GPR_ASSERT(item->obj_type == item_type); |
| 1421 | GPR_ASSERT(bag->obj_type == bag_type); |
| 1422 | #endif |
Craig Tiller | 57726ca | 2016-09-12 11:59:45 -0700 | [diff] [blame] | 1423 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1424 | grpc_error* error = GRPC_ERROR_NONE; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1425 | polling_island* pi_new = nullptr; |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1426 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1427 | gpr_mu_lock(&bag->mu); |
| 1428 | gpr_mu_lock(&item->mu); |
| 1429 | |
Craig Tiller | 7212c23 | 2016-07-06 13:11:09 -0700 | [diff] [blame] | 1430 | retry: |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1431 | /* |
| 1432 | * 1) If item->pi and bag->pi are both non-NULL and equal, do nothing |
| 1433 | * 2) If item->pi and bag->pi are both NULL, create a new polling island (with |
| 1434 | * a refcount of 2) and point item->pi and bag->pi to the new island |
| 1435 | * 3) If exactly one of item->pi or bag->pi is NULL, update it to point to |
| 1436 | * the other's non-NULL pi |
| 1437 | * 4) Finally if item->pi and bag-pi are non-NULL and not-equal, merge the |
| 1438 | * polling islands and update item->pi and bag->pi to point to the new |
| 1439 | * island |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1440 | */ |
Craig Tiller | 8e8027b | 2016-07-07 10:42:09 -0700 | [diff] [blame] | 1441 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1442 | /* Early out if we are trying to add an 'fd' to a 'bag' but the fd is already |
| 1443 | * orphaned */ |
| 1444 | if (item_type == POLL_OBJ_FD && (FD_FROM_PO(item))->orphaned) { |
| 1445 | gpr_mu_unlock(&item->mu); |
| 1446 | gpr_mu_unlock(&bag->mu); |
Craig Tiller | 42ac6db | 2016-07-06 17:13:56 -0700 | [diff] [blame] | 1447 | return; |
| 1448 | } |
| 1449 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1450 | if (item->pi == bag->pi) { |
| 1451 | pi_new = item->pi; |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1452 | if (pi_new == nullptr) { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1453 | /* GPR_ASSERT(item->pi == bag->pi == NULL) */ |
Sree Kuchibhotla | a129adf | 2016-10-26 16:44:44 -0700 | [diff] [blame] | 1454 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1455 | /* If we are adding an fd to a bag (i.e pollset or pollset_set), then |
| 1456 | * we need to do some extra work to make TSAN happy */ |
| 1457 | if (item_type == POLL_OBJ_FD) { |
| 1458 | /* Unlock before creating a new polling island: the polling island will |
| 1459 | create a workqueue which creates a file descriptor, and holding an fd |
| 1460 | lock here can eventually cause a loop to appear to TSAN (making it |
| 1461 | unhappy). We don't think it's a real loop (there's an epoch point |
| 1462 | where that loop possibility disappears), but the advantages of |
| 1463 | keeping TSAN happy outweigh any performance advantage we might have |
| 1464 | by keeping the lock held. */ |
| 1465 | gpr_mu_unlock(&item->mu); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1466 | pi_new = polling_island_create(FD_FROM_PO(item), &error); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1467 | gpr_mu_lock(&item->mu); |
Sree Kuchibhotla | a129adf | 2016-10-26 16:44:44 -0700 | [diff] [blame] | 1468 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1469 | /* Need to reverify any assumptions made between the initial lock and |
| 1470 | getting to this branch: if they've changed, we need to throw away our |
| 1471 | work and figure things out again. */ |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1472 | if (item->pi != nullptr) { |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1473 | GRPC_POLLING_TRACE( |
| 1474 | "add_poll_object: Raced creating new polling island. pi_new: %p " |
| 1475 | "(fd: %d, %s: %p)", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1476 | (void*)pi_new, FD_FROM_PO(item)->fd, poll_obj_string(bag_type), |
| 1477 | (void*)bag); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1478 | /* 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] | 1479 | and no one has a reference to it yet */ |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1480 | polling_island_remove_all_fds_locked(pi_new, true, &error); |
| 1481 | |
| 1482 | /* Ref and unref so that the polling island gets deleted during unref |
| 1483 | */ |
| 1484 | PI_ADD_REF(pi_new, "dance_of_destruction"); |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1485 | PI_UNREF(pi_new, "dance_of_destruction"); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1486 | goto retry; |
| 1487 | } |
Craig Tiller | 27da642 | 2016-07-06 13:14:46 -0700 | [diff] [blame] | 1488 | } else { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1489 | pi_new = polling_island_create(nullptr, &error); |
Craig Tiller | 7212c23 | 2016-07-06 13:11:09 -0700 | [diff] [blame] | 1490 | } |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1491 | |
| 1492 | GRPC_POLLING_TRACE( |
| 1493 | "add_poll_object: Created new polling island. pi_new: %p (%s: %p, " |
| 1494 | "%s: %p)", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1495 | (void*)pi_new, poll_obj_string(item_type), (void*)item, |
| 1496 | poll_obj_string(bag_type), (void*)bag); |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1497 | } else { |
| 1498 | GRPC_POLLING_TRACE( |
| 1499 | "add_poll_object: Same polling island. pi: %p (%s, %s)", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1500 | (void*)pi_new, poll_obj_string(item_type), poll_obj_string(bag_type)); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1501 | } |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1502 | } else if (item->pi == nullptr) { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1503 | /* GPR_ASSERT(bag->pi != NULL) */ |
| 1504 | /* Make pi_new point to latest pi*/ |
| 1505 | pi_new = polling_island_lock(bag->pi); |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1506 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1507 | if (item_type == POLL_OBJ_FD) { |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1508 | grpc_fd* fd = FD_FROM_PO(item); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1509 | polling_island_add_fds_locked(pi_new, &fd, 1, true, &error); |
| 1510 | } |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1511 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1512 | gpr_mu_unlock(&pi_new->mu); |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1513 | GRPC_POLLING_TRACE( |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1514 | "add_poll_obj: item->pi was NULL. pi_new: %p (item(%s): %p, " |
| 1515 | "bag(%s): %p)", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1516 | (void*)pi_new, poll_obj_string(item_type), (void*)item, |
| 1517 | poll_obj_string(bag_type), (void*)bag); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1518 | } else if (bag->pi == nullptr) { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1519 | /* GPR_ASSERT(item->pi != NULL) */ |
| 1520 | /* Make pi_new to point to latest pi */ |
| 1521 | pi_new = polling_island_lock(item->pi); |
| 1522 | gpr_mu_unlock(&pi_new->mu); |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1523 | GRPC_POLLING_TRACE( |
| 1524 | "add_poll_obj: bag->pi was NULL. pi_new: %p (item(%s): %p, " |
| 1525 | "bag(%s): %p)", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1526 | (void*)pi_new, poll_obj_string(item_type), (void*)item, |
| 1527 | poll_obj_string(bag_type), (void*)bag); |
Sree Kuchibhotla | 5098f91 | 2016-05-31 10:58:17 -0700 | [diff] [blame] | 1528 | } else { |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1529 | pi_new = polling_island_merge(item->pi, bag->pi, &error); |
Sree Kuchibhotla | 1e77668 | 2016-06-28 14:09:26 -0700 | [diff] [blame] | 1530 | GRPC_POLLING_TRACE( |
Sree Kuchibhotla | 499b94b | 2016-11-18 14:35:47 -0800 | [diff] [blame] | 1531 | "add_poll_obj: polling islands merged. pi_new: %p (item(%s): %p, " |
| 1532 | "bag(%s): %p)", |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1533 | (void*)pi_new, poll_obj_string(item_type), (void*)item, |
| 1534 | poll_obj_string(bag_type), (void*)bag); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1535 | } |
| 1536 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1537 | /* At this point, pi_new is the polling island that both item->pi and bag->pi |
| 1538 | MUST be pointing to */ |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1539 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1540 | if (item->pi != pi_new) { |
| 1541 | PI_ADD_REF(pi_new, poll_obj_string(item_type)); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1542 | if (item->pi != nullptr) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1543 | PI_UNREF(item->pi, poll_obj_string(item_type)); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1544 | } |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1545 | item->pi = pi_new; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1546 | } |
| 1547 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1548 | if (bag->pi != pi_new) { |
| 1549 | PI_ADD_REF(pi_new, poll_obj_string(bag_type)); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1550 | if (bag->pi != nullptr) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1551 | PI_UNREF(bag->pi, poll_obj_string(bag_type)); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1552 | } |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1553 | bag->pi = pi_new; |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1554 | } |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1555 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1556 | gpr_mu_unlock(&item->mu); |
| 1557 | gpr_mu_unlock(&bag->mu); |
Craig Tiller | 1500761 | 2016-07-06 09:36:16 -0700 | [diff] [blame] | 1558 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1559 | GRPC_LOG_IF_ERROR("add_poll_object", error); |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1560 | } |
Craig Tiller | 57726ca | 2016-09-12 11:59:45 -0700 | [diff] [blame] | 1561 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1562 | static void pollset_add_fd(grpc_pollset* pollset, grpc_fd* fd) { |
| 1563 | add_poll_object(&pollset->po, POLL_OBJ_POLLSET, &fd->po, POLL_OBJ_FD); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1564 | } |
| 1565 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1566 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1567 | * Pollset-set Definitions |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1568 | */ |
| 1569 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1570 | static grpc_pollset_set* pollset_set_create(void) { |
Noah Eisen | 4d20a66 | 2018-02-09 09:34:04 -0800 | [diff] [blame] | 1571 | grpc_pollset_set* pss = |
| 1572 | static_cast<grpc_pollset_set*>(gpr_malloc(sizeof(*pss))); |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1573 | gpr_mu_init(&pss->po.mu); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1574 | pss->po.pi = nullptr; |
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 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1581 | static void pollset_set_destroy(grpc_pollset_set* pss) { |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1582 | gpr_mu_destroy(&pss->po.mu); |
| 1583 | |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1584 | if (pss->po.pi != nullptr) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1585 | PI_UNREF(pss->po.pi, "pss_destroy"); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1586 | } |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1587 | |
| 1588 | gpr_free(pss); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1589 | } |
| 1590 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1591 | static void pollset_set_add_fd(grpc_pollset_set* pss, grpc_fd* fd) { |
| 1592 | add_poll_object(&pss->po, POLL_OBJ_POLLSET_SET, &fd->po, POLL_OBJ_FD); |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1593 | } |
| 1594 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1595 | static void pollset_set_del_fd(grpc_pollset_set* pss, grpc_fd* fd) { |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1596 | /* Nothing to do */ |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1597 | } |
| 1598 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1599 | static void pollset_set_add_pollset(grpc_pollset_set* pss, grpc_pollset* ps) { |
| 1600 | add_poll_object(&pss->po, POLL_OBJ_POLLSET_SET, &ps->po, POLL_OBJ_POLLSET); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1601 | } |
| 1602 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1603 | static void pollset_set_del_pollset(grpc_pollset_set* pss, grpc_pollset* ps) { |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1604 | /* Nothing to do */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1605 | } |
| 1606 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1607 | static void pollset_set_add_pollset_set(grpc_pollset_set* bag, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1608 | grpc_pollset_set* item) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1609 | add_poll_object(&bag->po, POLL_OBJ_POLLSET_SET, &item->po, |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1610 | POLL_OBJ_POLLSET_SET); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1611 | } |
| 1612 | |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1613 | static void pollset_set_del_pollset_set(grpc_pollset_set* bag, |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1614 | grpc_pollset_set* item) { |
Sree Kuchibhotla | 2385fd7 | 2016-11-18 16:30:41 -0800 | [diff] [blame] | 1615 | /* Nothing to do */ |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1616 | } |
| 1617 | |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1618 | /* Test helper functions |
| 1619 | * */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1620 | void* grpc_fd_get_polling_island(grpc_fd* fd) { |
| 1621 | polling_island* pi; |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1622 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1623 | gpr_mu_lock(&fd->po.mu); |
| 1624 | pi = fd->po.pi; |
| 1625 | gpr_mu_unlock(&fd->po.mu); |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1626 | |
| 1627 | return pi; |
| 1628 | } |
| 1629 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1630 | void* grpc_pollset_get_polling_island(grpc_pollset* ps) { |
| 1631 | polling_island* pi; |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1632 | |
Sree Kuchibhotla | f6f33d7 | 2016-11-18 11:38:52 -0800 | [diff] [blame] | 1633 | gpr_mu_lock(&ps->po.mu); |
| 1634 | pi = ps->po.pi; |
| 1635 | gpr_mu_unlock(&ps->po.mu); |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1636 | |
| 1637 | return pi; |
| 1638 | } |
| 1639 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1640 | bool grpc_are_polling_islands_equal(void* p, void* q) { |
Noah Eisen | be82e64 | 2018-02-09 09:16:55 -0800 | [diff] [blame] | 1641 | polling_island* p1 = static_cast<polling_island*>(p); |
| 1642 | polling_island* p2 = static_cast<polling_island*>(q); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1643 | |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1644 | /* Note: polling_island_lock_pair() may change p1 and p2 to point to the |
| 1645 | latest polling islands in their respective linked lists */ |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1646 | polling_island_lock_pair(&p1, &p2); |
Sree Kuchibhotla | 20d0a16 | 2016-06-23 15:14:03 -0700 | [diff] [blame] | 1647 | polling_island_unlock_pair(p1, p2); |
Sree Kuchibhotla | 2f8ade0 | 2016-06-17 13:28:38 -0700 | [diff] [blame] | 1648 | |
| 1649 | return p1 == p2; |
Sree Kuchibhotla | 2e12db9 | 2016-06-16 16:53:59 -0700 | [diff] [blame] | 1650 | } |
| 1651 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1652 | /******************************************************************************* |
Sree Kuchibhotla | 0bcbd79 | 2016-06-01 15:43:03 -0700 | [diff] [blame] | 1653 | * Event engine binding |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1654 | */ |
| 1655 | |
| 1656 | static void shutdown_engine(void) { |
| 1657 | fd_global_shutdown(); |
| 1658 | pollset_global_shutdown(); |
Sree Kuchibhotla | d627c10 | 2016-06-06 15:49:32 -0700 | [diff] [blame] | 1659 | polling_island_global_shutdown(); |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1660 | } |
| 1661 | |
| 1662 | static const grpc_event_engine_vtable vtable = { |
Yash Tibrewal | 533d118 | 2017-09-18 10:48:22 -0700 | [diff] [blame] | 1663 | sizeof(grpc_pollset), |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 1664 | true, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1665 | |
Yash Tibrewal | 533d118 | 2017-09-18 10:48:22 -0700 | [diff] [blame] | 1666 | fd_create, |
| 1667 | fd_wrapped_fd, |
| 1668 | fd_orphan, |
| 1669 | fd_shutdown, |
| 1670 | fd_notify_on_read, |
| 1671 | fd_notify_on_write, |
Yash Tibrewal | adc733f | 2018-04-02 18:32:06 -0700 | [diff] [blame^] | 1672 | fd_notify_on_error, |
Yash Tibrewal | 533d118 | 2017-09-18 10:48:22 -0700 | [diff] [blame] | 1673 | fd_is_shutdown, |
| 1674 | fd_get_read_notifier_pollset, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1675 | |
Yash Tibrewal | 533d118 | 2017-09-18 10:48:22 -0700 | [diff] [blame] | 1676 | pollset_init, |
| 1677 | pollset_shutdown, |
| 1678 | pollset_destroy, |
| 1679 | pollset_work, |
| 1680 | pollset_kick, |
| 1681 | pollset_add_fd, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1682 | |
Yash Tibrewal | 533d118 | 2017-09-18 10:48:22 -0700 | [diff] [blame] | 1683 | pollset_set_create, |
| 1684 | pollset_set_destroy, |
| 1685 | pollset_set_add_pollset, |
| 1686 | pollset_set_del_pollset, |
| 1687 | pollset_set_add_pollset_set, |
| 1688 | pollset_set_del_pollset_set, |
| 1689 | pollset_set_add_fd, |
| 1690 | pollset_set_del_fd, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1691 | |
Yash Tibrewal | 533d118 | 2017-09-18 10:48:22 -0700 | [diff] [blame] | 1692 | shutdown_engine, |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1693 | }; |
| 1694 | |
Sree Kuchibhotla | 7274402 | 2016-06-09 09:42:06 -0700 | [diff] [blame] | 1695 | /* It is possible that GLIBC has epoll but the underlying kernel doesn't. |
| 1696 | * Create a dummy epoll_fd to make sure epoll support is available */ |
| 1697 | static bool is_epoll_available() { |
| 1698 | int fd = epoll_create1(EPOLL_CLOEXEC); |
| 1699 | if (fd < 0) { |
| 1700 | gpr_log( |
| 1701 | GPR_ERROR, |
| 1702 | "epoll_create1 failed with error: %d. Not using epoll polling engine", |
| 1703 | fd); |
| 1704 | return false; |
| 1705 | } |
| 1706 | close(fd); |
| 1707 | return true; |
| 1708 | } |
| 1709 | |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1710 | const grpc_event_engine_vtable* grpc_init_epollsig_linux( |
Craig Tiller | f8382b8 | 2017-04-27 15:09:48 -0700 | [diff] [blame] | 1711 | bool explicit_request) { |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1712 | /* If use of signals is disabled, we cannot use epoll engine*/ |
| 1713 | if (is_grpc_wakeup_signal_initialized && grpc_wakeup_signal < 0) { |
yang-g | 30101b0 | 2017-11-06 14:35:30 -0800 | [diff] [blame] | 1714 | gpr_log(GPR_ERROR, "Skipping epollsig because use of signals is disabled."); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1715 | return nullptr; |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1716 | } |
| 1717 | |
Ken Payson | cd7d047 | 2016-10-11 12:24:20 -0700 | [diff] [blame] | 1718 | if (!grpc_has_wakeup_fd()) { |
yang-g | 30101b0 | 2017-11-06 14:35:30 -0800 | [diff] [blame] | 1719 | gpr_log(GPR_ERROR, "Skipping epollsig because of no wakeup fd."); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1720 | return nullptr; |
Ken Payson | bc544be | 2016-10-06 19:23:47 -0700 | [diff] [blame] | 1721 | } |
| 1722 | |
Sree Kuchibhotla | 7274402 | 2016-06-09 09:42:06 -0700 | [diff] [blame] | 1723 | if (!is_epoll_available()) { |
yang-g | 30101b0 | 2017-11-06 14:35:30 -0800 | [diff] [blame] | 1724 | gpr_log(GPR_ERROR, "Skipping epollsig because epoll is unavailable."); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1725 | return nullptr; |
Sree Kuchibhotla | 7274402 | 2016-06-09 09:42:06 -0700 | [diff] [blame] | 1726 | } |
| 1727 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1728 | if (!is_grpc_wakeup_signal_initialized) { |
Sree Kuchibhotla | 0fda880 | 2017-08-30 20:34:51 -0700 | [diff] [blame] | 1729 | if (explicit_request) { |
Craig Tiller | f8382b8 | 2017-04-27 15:09:48 -0700 | [diff] [blame] | 1730 | grpc_use_signal(SIGRTMIN + 6); |
| 1731 | } else { |
yang-g | 30101b0 | 2017-11-06 14:35:30 -0800 | [diff] [blame] | 1732 | gpr_log(GPR_ERROR, |
| 1733 | "Skipping epollsig because uninitialized wakeup signal."); |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1734 | return nullptr; |
Craig Tiller | f8382b8 | 2017-04-27 15:09:48 -0700 | [diff] [blame] | 1735 | } |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1736 | } |
| 1737 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1738 | fd_global_init(); |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1739 | |
| 1740 | if (!GRPC_LOG_IF_ERROR("pollset_global_init", pollset_global_init())) { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1741 | return nullptr; |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1742 | } |
| 1743 | |
| 1744 | if (!GRPC_LOG_IF_ERROR("polling_island_global_init", |
| 1745 | polling_island_global_init())) { |
Craig Tiller | 4782d92 | 2017-11-10 09:53:21 -0800 | [diff] [blame] | 1746 | return nullptr; |
Sree Kuchibhotla | 3131c26 | 2016-06-21 17:28:28 -0700 | [diff] [blame] | 1747 | } |
| 1748 | |
Sree Kuchibhotla | f448c34 | 2016-05-19 10:51:24 -0700 | [diff] [blame] | 1749 | return &vtable; |
| 1750 | } |
| 1751 | |
Mehrdad Afshari | fb66900 | 2018-01-17 15:37:56 -0800 | [diff] [blame] | 1752 | #else /* defined(GRPC_LINUX_EPOLL_CREATE1) */ |
murgatroid99 | 623dd4f | 2016-08-08 17:31:27 -0700 | [diff] [blame] | 1753 | #if defined(GRPC_POSIX_SOCKET) |
Yash Tibrewal | 1cac223 | 2017-09-26 11:31:11 -0700 | [diff] [blame] | 1754 | #include "src/core/lib/iomgr/ev_epollsig_linux.h" |
Mehrdad Afshari | fb66900 | 2018-01-17 15:37:56 -0800 | [diff] [blame] | 1755 | /* If GRPC_LINUX_EPOLL_CREATE1 is not defined, it means |
| 1756 | epoll_create1 is not available. Return NULL */ |
Craig Tiller | baa14a9 | 2017-11-03 09:09:36 -0700 | [diff] [blame] | 1757 | const grpc_event_engine_vtable* grpc_init_epollsig_linux( |
Craig Tiller | f8382b8 | 2017-04-27 15:09:48 -0700 | [diff] [blame] | 1758 | bool explicit_request) { |
Yash Tibrewal | 8cf1470 | 2017-12-06 09:47:54 -0800 | [diff] [blame] | 1759 | return nullptr; |
Craig Tiller | f8382b8 | 2017-04-27 15:09:48 -0700 | [diff] [blame] | 1760 | } |
murgatroid99 | 623dd4f | 2016-08-08 17:31:27 -0700 | [diff] [blame] | 1761 | #endif /* defined(GRPC_POSIX_SOCKET) */ |
Sree Kuchibhotla | 5855c47 | 2016-06-08 12:56:56 -0700 | [diff] [blame] | 1762 | |
Sree Kuchibhotla | c7be7c6 | 2016-06-09 17:08:50 -0700 | [diff] [blame] | 1763 | void grpc_use_signal(int signum) {} |
Mehrdad Afshari | fb66900 | 2018-01-17 15:37:56 -0800 | [diff] [blame] | 1764 | #endif /* !defined(GRPC_LINUX_EPOLL_CREATE1) */ |