| 1 | /* |
| 2 | * lttng-ring-buffer-client.h |
| 3 | * |
| 4 | * LTTng lib ring buffer client template. |
| 5 | * |
| 6 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 7 | * |
| 8 | * This library is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU Lesser General Public |
| 10 | * License as published by the Free Software Foundation; only |
| 11 | * version 2.1 of the License. |
| 12 | * |
| 13 | * This library is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * Lesser General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU Lesser General Public |
| 19 | * License along with this library; if not, write to the Free Software |
| 20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 21 | */ |
| 22 | |
| 23 | #include <stddef.h> |
| 24 | #include <stdint.h> |
| 25 | #include <lttng/ust-events.h> |
| 26 | #include "lttng/bitfield.h" |
| 27 | #include "lttng-tracer.h" |
| 28 | #include "../libringbuffer/frontend_types.h" |
| 29 | |
| 30 | struct metadata_packet_header { |
| 31 | uint32_t magic; /* 0x75D11D57 */ |
| 32 | uint8_t uuid[LTTNG_UST_UUID_LEN]; /* Unique Universal Identifier */ |
| 33 | uint32_t checksum; /* 0 if unused */ |
| 34 | uint32_t content_size; /* in bits */ |
| 35 | uint32_t packet_size; /* in bits */ |
| 36 | uint8_t compression_scheme; /* 0 if unused */ |
| 37 | uint8_t encryption_scheme; /* 0 if unused */ |
| 38 | uint8_t checksum_scheme; /* 0 if unused */ |
| 39 | uint8_t major; /* CTF spec major version number */ |
| 40 | uint8_t minor; /* CTF spec minor version number */ |
| 41 | uint8_t header_end[0]; |
| 42 | }; |
| 43 | |
| 44 | struct metadata_record_header { |
| 45 | uint8_t header_end[0]; /* End of header */ |
| 46 | }; |
| 47 | |
| 48 | static const struct lttng_ust_lib_ring_buffer_config client_config; |
| 49 | |
| 50 | static inline uint64_t lib_ring_buffer_clock_read(struct channel *chan) |
| 51 | { |
| 52 | return 0; |
| 53 | } |
| 54 | |
| 55 | static inline |
| 56 | size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config, |
| 57 | struct channel *chan, size_t offset, |
| 58 | size_t *pre_header_padding, |
| 59 | struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 60 | void *client_ctx) |
| 61 | { |
| 62 | return 0; |
| 63 | } |
| 64 | |
| 65 | #include "../libringbuffer/api.h" |
| 66 | #include "lttng-rb-clients.h" |
| 67 | |
| 68 | static uint64_t client_ring_buffer_clock_read(struct channel *chan) |
| 69 | { |
| 70 | return 0; |
| 71 | } |
| 72 | |
| 73 | static |
| 74 | size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config, |
| 75 | struct channel *chan, size_t offset, |
| 76 | size_t *pre_header_padding, |
| 77 | struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 78 | void *client_ctx) |
| 79 | { |
| 80 | return 0; |
| 81 | } |
| 82 | |
| 83 | /** |
| 84 | * client_packet_header_size - called on buffer-switch to a new sub-buffer |
| 85 | * |
| 86 | * Return header size without padding after the structure. Don't use packed |
| 87 | * structure because gcc generates inefficient code on some architectures |
| 88 | * (powerpc, mips..) |
| 89 | */ |
| 90 | static size_t client_packet_header_size(void) |
| 91 | { |
| 92 | return offsetof(struct metadata_packet_header, header_end); |
| 93 | } |
| 94 | |
| 95 | static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc, |
| 96 | unsigned int subbuf_idx, |
| 97 | struct lttng_ust_shm_handle *handle) |
| 98 | { |
| 99 | struct channel *chan = shmp(handle, buf->backend.chan); |
| 100 | struct metadata_packet_header *header = |
| 101 | (struct metadata_packet_header *) |
| 102 | lib_ring_buffer_offset_address(&buf->backend, |
| 103 | subbuf_idx * chan->backend.subbuf_size, |
| 104 | handle); |
| 105 | struct lttng_channel *lttng_chan = channel_get_private(chan); |
| 106 | |
| 107 | assert(header); |
| 108 | if (!header) |
| 109 | return; |
| 110 | header->magic = TSDL_MAGIC_NUMBER; |
| 111 | memcpy(header->uuid, lttng_chan->uuid, sizeof(lttng_chan->uuid)); |
| 112 | header->checksum = 0; /* 0 if unused */ |
| 113 | header->content_size = 0xFFFFFFFF; /* in bits, for debugging */ |
| 114 | header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */ |
| 115 | header->compression_scheme = 0; /* 0 if unused */ |
| 116 | header->encryption_scheme = 0; /* 0 if unused */ |
| 117 | header->checksum_scheme = 0; /* 0 if unused */ |
| 118 | header->major = CTF_SPEC_MAJOR; |
| 119 | header->minor = CTF_SPEC_MINOR; |
| 120 | } |
| 121 | |
| 122 | /* |
| 123 | * offset is assumed to never be 0 here : never deliver a completely empty |
| 124 | * subbuffer. data_size is between 1 and subbuf_size. |
| 125 | */ |
| 126 | static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc, |
| 127 | unsigned int subbuf_idx, unsigned long data_size, |
| 128 | struct lttng_ust_shm_handle *handle) |
| 129 | { |
| 130 | struct channel *chan = shmp(handle, buf->backend.chan); |
| 131 | struct metadata_packet_header *header = |
| 132 | (struct metadata_packet_header *) |
| 133 | lib_ring_buffer_offset_address(&buf->backend, |
| 134 | subbuf_idx * chan->backend.subbuf_size, |
| 135 | handle); |
| 136 | unsigned long records_lost = 0; |
| 137 | |
| 138 | assert(header); |
| 139 | if (!header) |
| 140 | return; |
| 141 | header->content_size = data_size * CHAR_BIT; /* in bits */ |
| 142 | header->packet_size = LTTNG_UST_PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */ |
| 143 | /* |
| 144 | * We do not care about the records lost count, because the metadata |
| 145 | * channel waits and retry. |
| 146 | */ |
| 147 | (void) lib_ring_buffer_get_records_lost_full(&client_config, buf); |
| 148 | records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf); |
| 149 | records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf); |
| 150 | WARN_ON_ONCE(records_lost != 0); |
| 151 | } |
| 152 | |
| 153 | static int client_buffer_create(struct lttng_ust_lib_ring_buffer *buf, void *priv, |
| 154 | int cpu, const char *name, |
| 155 | struct lttng_ust_shm_handle *handle) |
| 156 | { |
| 157 | return 0; |
| 158 | } |
| 159 | |
| 160 | static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf, |
| 161 | void *priv, int cpu, |
| 162 | struct lttng_ust_shm_handle *handle) |
| 163 | { |
| 164 | } |
| 165 | |
| 166 | static const |
| 167 | struct lttng_ust_client_lib_ring_buffer_client_cb client_cb = { |
| 168 | .parent = { |
| 169 | .ring_buffer_clock_read = client_ring_buffer_clock_read, |
| 170 | .record_header_size = client_record_header_size, |
| 171 | .subbuffer_header_size = client_packet_header_size, |
| 172 | .buffer_begin = client_buffer_begin, |
| 173 | .buffer_end = client_buffer_end, |
| 174 | .buffer_create = client_buffer_create, |
| 175 | .buffer_finalize = client_buffer_finalize, |
| 176 | }, |
| 177 | }; |
| 178 | |
| 179 | static const struct lttng_ust_lib_ring_buffer_config client_config = { |
| 180 | .cb.ring_buffer_clock_read = client_ring_buffer_clock_read, |
| 181 | .cb.record_header_size = client_record_header_size, |
| 182 | .cb.subbuffer_header_size = client_packet_header_size, |
| 183 | .cb.buffer_begin = client_buffer_begin, |
| 184 | .cb.buffer_end = client_buffer_end, |
| 185 | .cb.buffer_create = client_buffer_create, |
| 186 | .cb.buffer_finalize = client_buffer_finalize, |
| 187 | |
| 188 | .tsc_bits = 0, |
| 189 | .alloc = RING_BUFFER_ALLOC_GLOBAL, |
| 190 | .sync = RING_BUFFER_SYNC_GLOBAL, |
| 191 | .mode = RING_BUFFER_MODE_TEMPLATE, |
| 192 | .backend = RING_BUFFER_PAGE, |
| 193 | .output = RING_BUFFER_MMAP, |
| 194 | .oops = RING_BUFFER_OOPS_CONSISTENCY, |
| 195 | .ipi = RING_BUFFER_NO_IPI_BARRIER, |
| 196 | .wakeup = RING_BUFFER_WAKEUP_BY_WRITER, |
| 197 | .client_type = LTTNG_CLIENT_TYPE, |
| 198 | |
| 199 | .cb_ptr = &client_cb.parent, |
| 200 | }; |
| 201 | |
| 202 | const struct lttng_ust_client_lib_ring_buffer_client_cb *LTTNG_CLIENT_CALLBACKS = &client_cb; |
| 203 | |
| 204 | static |
| 205 | struct lttng_channel *_channel_create(const char *name, |
| 206 | void *buf_addr, |
| 207 | size_t subbuf_size, size_t num_subbuf, |
| 208 | unsigned int switch_timer_interval, |
| 209 | unsigned int read_timer_interval, |
| 210 | unsigned char *uuid, |
| 211 | uint32_t chan_id, |
| 212 | const int *stream_fds, int nr_stream_fds, |
| 213 | int64_t blocking_timeout) |
| 214 | { |
| 215 | struct lttng_channel chan_priv_init; |
| 216 | struct lttng_ust_shm_handle *handle; |
| 217 | struct lttng_channel *lttng_chan; |
| 218 | void *priv; |
| 219 | |
| 220 | memset(&chan_priv_init, 0, sizeof(chan_priv_init)); |
| 221 | memcpy(chan_priv_init.uuid, uuid, LTTNG_UST_UUID_LEN); |
| 222 | chan_priv_init.id = chan_id; |
| 223 | handle = channel_create(&client_config, name, |
| 224 | &priv, __alignof__(struct lttng_channel), |
| 225 | sizeof(struct lttng_channel), |
| 226 | &chan_priv_init, |
| 227 | buf_addr, subbuf_size, num_subbuf, |
| 228 | switch_timer_interval, read_timer_interval, |
| 229 | stream_fds, nr_stream_fds, blocking_timeout); |
| 230 | if (!handle) |
| 231 | return NULL; |
| 232 | lttng_chan = priv; |
| 233 | lttng_chan->handle = handle; |
| 234 | lttng_chan->chan = shmp(handle, handle->chan); |
| 235 | return lttng_chan; |
| 236 | } |
| 237 | |
| 238 | static |
| 239 | void lttng_channel_destroy(struct lttng_channel *chan) |
| 240 | { |
| 241 | channel_destroy(chan->chan, chan->handle, 1); |
| 242 | } |
| 243 | |
| 244 | static |
| 245 | int lttng_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx, uint32_t event_id) |
| 246 | { |
| 247 | int ret; |
| 248 | |
| 249 | ret = lib_ring_buffer_reserve(&client_config, ctx, NULL); |
| 250 | if (ret) |
| 251 | return ret; |
| 252 | if (caa_likely(ctx->ctx_len |
| 253 | >= sizeof(struct lttng_ust_lib_ring_buffer_ctx))) { |
| 254 | if (lib_ring_buffer_backend_get_pages(&client_config, ctx, |
| 255 | &ctx->backend_pages)) |
| 256 | return -EPERM; |
| 257 | } |
| 258 | return 0; |
| 259 | } |
| 260 | |
| 261 | static |
| 262 | void lttng_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx) |
| 263 | { |
| 264 | lib_ring_buffer_commit(&client_config, ctx); |
| 265 | } |
| 266 | |
| 267 | static |
| 268 | void lttng_event_write(struct lttng_ust_lib_ring_buffer_ctx *ctx, const void *src, |
| 269 | size_t len) |
| 270 | { |
| 271 | lib_ring_buffer_write(&client_config, ctx, src, len); |
| 272 | } |
| 273 | |
| 274 | static |
| 275 | size_t lttng_packet_avail_size(struct channel *chan, struct lttng_ust_shm_handle *handle) |
| 276 | { |
| 277 | unsigned long o_begin; |
| 278 | struct lttng_ust_lib_ring_buffer *buf; |
| 279 | |
| 280 | buf = shmp(handle, chan->backend.buf[0].shmp); /* Only for global buffer ! */ |
| 281 | o_begin = v_read(&client_config, &buf->offset); |
| 282 | if (subbuf_offset(o_begin, chan) != 0) { |
| 283 | return chan->backend.subbuf_size - subbuf_offset(o_begin, chan); |
| 284 | } else { |
| 285 | return chan->backend.subbuf_size - subbuf_offset(o_begin, chan) |
| 286 | - sizeof(struct metadata_packet_header); |
| 287 | } |
| 288 | } |
| 289 | |
| 290 | #if 0 |
| 291 | static |
| 292 | wait_queue_head_t *lttng_get_reader_wait_queue(struct channel *chan) |
| 293 | { |
| 294 | return &chan->read_wait; |
| 295 | } |
| 296 | |
| 297 | static |
| 298 | wait_queue_head_t *lttng_get_hp_wait_queue(struct channel *chan) |
| 299 | { |
| 300 | return &chan->hp_wait; |
| 301 | } |
| 302 | #endif //0 |
| 303 | |
| 304 | static |
| 305 | int lttng_is_finalized(struct channel *chan) |
| 306 | { |
| 307 | return lib_ring_buffer_channel_is_finalized(chan); |
| 308 | } |
| 309 | |
| 310 | static |
| 311 | int lttng_is_disabled(struct channel *chan) |
| 312 | { |
| 313 | return lib_ring_buffer_channel_is_disabled(chan); |
| 314 | } |
| 315 | |
| 316 | static |
| 317 | int lttng_flush_buffer(struct channel *chan, struct lttng_ust_shm_handle *handle) |
| 318 | { |
| 319 | struct lttng_ust_lib_ring_buffer *buf; |
| 320 | int shm_fd, wait_fd, wakeup_fd; |
| 321 | uint64_t memory_map_size; |
| 322 | |
| 323 | buf = channel_get_ring_buffer(&client_config, chan, |
| 324 | 0, handle, &shm_fd, &wait_fd, &wakeup_fd, |
| 325 | &memory_map_size); |
| 326 | lib_ring_buffer_switch(&client_config, buf, |
| 327 | SWITCH_ACTIVE, handle); |
| 328 | return 0; |
| 329 | } |
| 330 | |
| 331 | static struct lttng_transport lttng_relay_transport = { |
| 332 | .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap", |
| 333 | .ops = { |
| 334 | .channel_create = _channel_create, |
| 335 | .channel_destroy = lttng_channel_destroy, |
| 336 | .event_reserve = lttng_event_reserve, |
| 337 | .event_commit = lttng_event_commit, |
| 338 | .event_write = lttng_event_write, |
| 339 | .packet_avail_size = lttng_packet_avail_size, |
| 340 | //.get_reader_wait_queue = lttng_get_reader_wait_queue, |
| 341 | //.get_hp_wait_queue = lttng_get_hp_wait_queue, |
| 342 | .is_finalized = lttng_is_finalized, |
| 343 | .is_disabled = lttng_is_disabled, |
| 344 | .flush_buffer = lttng_flush_buffer, |
| 345 | }, |
| 346 | .client_config = &client_config, |
| 347 | }; |
| 348 | |
| 349 | void RING_BUFFER_MODE_TEMPLATE_INIT(void) |
| 350 | { |
| 351 | DBG("LTT : ltt ring buffer client \"%s\" init\n", |
| 352 | "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap"); |
| 353 | lttng_transport_register(<tng_relay_transport); |
| 354 | } |
| 355 | |
| 356 | void RING_BUFFER_MODE_TEMPLATE_EXIT(void) |
| 357 | { |
| 358 | DBG("LTT : ltt ring buffer client \"%s\" exit\n", |
| 359 | "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap"); |
| 360 | lttng_transport_unregister(<tng_relay_transport); |
| 361 | } |