| 1 | /* |
| 2 | * SPDX-License-Identifier: LGPL-2.1-only |
| 3 | * |
| 4 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 5 | * |
| 6 | * LTTng lib ring buffer client template. |
| 7 | */ |
| 8 | |
| 9 | #include <limits.h> |
| 10 | #include <stddef.h> |
| 11 | #include <stdint.h> |
| 12 | |
| 13 | #include <ust-events-internal.h> |
| 14 | #include <lttng/urcu/pointer.h> |
| 15 | #include "ust-bitfield.h" |
| 16 | #include "ust-compat.h" |
| 17 | #include "clock.h" |
| 18 | #include "context-internal.h" |
| 19 | #include "lttng-tracer.h" |
| 20 | #include "../libringbuffer/frontend_types.h" |
| 21 | #include <urcu/tls-compat.h> |
| 22 | |
| 23 | #define LTTNG_COMPACT_EVENT_BITS 5 |
| 24 | #define LTTNG_COMPACT_TSC_BITS 27 |
| 25 | |
| 26 | enum app_ctx_mode { |
| 27 | APP_CTX_DISABLED, |
| 28 | APP_CTX_ENABLED, |
| 29 | }; |
| 30 | |
| 31 | /* |
| 32 | * Keep the natural field alignment for _each field_ within this structure if |
| 33 | * you ever add/remove a field from this header. Packed attribute is not used |
| 34 | * because gcc generates poor code on at least powerpc and mips. Don't ever |
| 35 | * let gcc add padding between the structure elements. |
| 36 | */ |
| 37 | |
| 38 | struct packet_header { |
| 39 | /* Trace packet header */ |
| 40 | uint32_t magic; /* |
| 41 | * Trace magic number. |
| 42 | * contains endianness information. |
| 43 | */ |
| 44 | uint8_t uuid[LTTNG_UST_UUID_LEN]; |
| 45 | uint32_t stream_id; |
| 46 | uint64_t stream_instance_id; |
| 47 | |
| 48 | struct { |
| 49 | /* Stream packet context */ |
| 50 | uint64_t timestamp_begin; /* Cycle count at subbuffer start */ |
| 51 | uint64_t timestamp_end; /* Cycle count at subbuffer end */ |
| 52 | uint64_t content_size; /* Size of data in subbuffer */ |
| 53 | uint64_t packet_size; /* Subbuffer size (include padding) */ |
| 54 | uint64_t packet_seq_num; /* Packet sequence number */ |
| 55 | unsigned long events_discarded; /* |
| 56 | * Events lost in this subbuffer since |
| 57 | * the beginning of the trace. |
| 58 | * (may overflow) |
| 59 | */ |
| 60 | uint32_t cpu_id; /* CPU id associated with stream */ |
| 61 | uint8_t header_end; /* End of header */ |
| 62 | } ctx; |
| 63 | }; |
| 64 | |
| 65 | struct lttng_client_ctx { |
| 66 | size_t packet_context_len; |
| 67 | size_t event_context_len; |
| 68 | struct lttng_ust_ctx *chan_ctx; |
| 69 | struct lttng_ust_ctx *event_ctx; |
| 70 | }; |
| 71 | |
| 72 | /* |
| 73 | * Indexed by lib_ring_buffer_nesting_count(). |
| 74 | */ |
| 75 | typedef struct lttng_ust_lib_ring_buffer_ctx_private private_ctx_stack_t[LIB_RING_BUFFER_MAX_NESTING]; |
| 76 | static DEFINE_URCU_TLS(private_ctx_stack_t, private_ctx_stack); |
| 77 | |
| 78 | /* |
| 79 | * Force a read (imply TLS fixup for dlopen) of TLS variables. |
| 80 | */ |
| 81 | static |
| 82 | void lttng_fixup_rb_client_tls(void) |
| 83 | { |
| 84 | asm volatile ("" : : "m" (URCU_TLS(private_ctx_stack))); |
| 85 | } |
| 86 | |
| 87 | static inline uint64_t lib_ring_buffer_clock_read(struct lttng_ust_lib_ring_buffer_channel *chan) |
| 88 | { |
| 89 | return trace_clock_read64(); |
| 90 | } |
| 91 | |
| 92 | static inline |
| 93 | size_t ctx_get_aligned_size(size_t offset, struct lttng_ust_ctx *ctx, |
| 94 | size_t ctx_len) |
| 95 | { |
| 96 | size_t orig_offset = offset; |
| 97 | |
| 98 | if (caa_likely(!ctx)) |
| 99 | return 0; |
| 100 | offset += lttng_ust_lib_ring_buffer_align(offset, ctx->largest_align); |
| 101 | offset += ctx_len; |
| 102 | return offset - orig_offset; |
| 103 | } |
| 104 | |
| 105 | static inline |
| 106 | void ctx_get_struct_size(struct lttng_ust_ctx *ctx, size_t *ctx_len, |
| 107 | enum app_ctx_mode mode) |
| 108 | { |
| 109 | int i; |
| 110 | size_t offset = 0; |
| 111 | |
| 112 | if (caa_likely(!ctx)) { |
| 113 | *ctx_len = 0; |
| 114 | return; |
| 115 | } |
| 116 | for (i = 0; i < ctx->nr_fields; i++) { |
| 117 | if (mode == APP_CTX_ENABLED) { |
| 118 | offset += ctx->fields[i]->get_size(ctx->fields[i], offset); |
| 119 | } else { |
| 120 | if (lttng_context_is_app(ctx->fields[i]->event_field->name)) { |
| 121 | /* |
| 122 | * Before UST 2.8, we cannot use the |
| 123 | * application context, because we |
| 124 | * cannot trust that the handler used |
| 125 | * for get_size is the same used for |
| 126 | * ctx_record, which would result in |
| 127 | * corrupted traces when tracing |
| 128 | * concurrently with application context |
| 129 | * register/unregister. |
| 130 | */ |
| 131 | offset += lttng_ust_dummy_get_size(ctx->fields[i], offset); |
| 132 | } else { |
| 133 | offset += ctx->fields[i]->get_size(ctx->fields[i], offset); |
| 134 | } |
| 135 | } |
| 136 | } |
| 137 | *ctx_len = offset; |
| 138 | } |
| 139 | |
| 140 | static inline |
| 141 | void ctx_record(struct lttng_ust_lib_ring_buffer_ctx *bufctx, |
| 142 | struct lttng_ust_channel_buffer *chan, |
| 143 | struct lttng_ust_ctx *ctx, |
| 144 | enum app_ctx_mode mode) |
| 145 | { |
| 146 | int i; |
| 147 | |
| 148 | if (caa_likely(!ctx)) |
| 149 | return; |
| 150 | lttng_ust_lib_ring_buffer_align_ctx(bufctx, ctx->largest_align); |
| 151 | for (i = 0; i < ctx->nr_fields; i++) { |
| 152 | if (mode == APP_CTX_ENABLED) { |
| 153 | ctx->fields[i]->record(ctx->fields[i], bufctx, chan); |
| 154 | } else { |
| 155 | if (lttng_context_is_app(ctx->fields[i]->event_field->name)) { |
| 156 | /* |
| 157 | * Before UST 2.8, we cannot use the |
| 158 | * application context, because we |
| 159 | * cannot trust that the handler used |
| 160 | * for get_size is the same used for |
| 161 | * ctx_record, which would result in |
| 162 | * corrupted traces when tracing |
| 163 | * concurrently with application context |
| 164 | * register/unregister. |
| 165 | */ |
| 166 | lttng_ust_dummy_record(ctx->fields[i], bufctx, chan); |
| 167 | } else { |
| 168 | ctx->fields[i]->record(ctx->fields[i], bufctx, chan); |
| 169 | } |
| 170 | } |
| 171 | } |
| 172 | } |
| 173 | |
| 174 | /* |
| 175 | * record_header_size - Calculate the header size and padding necessary. |
| 176 | * @config: ring buffer instance configuration |
| 177 | * @chan: channel |
| 178 | * @offset: offset in the write buffer |
| 179 | * @pre_header_padding: padding to add before the header (output) |
| 180 | * @ctx: reservation context |
| 181 | * |
| 182 | * Returns the event header size (including padding). |
| 183 | * |
| 184 | * The payload must itself determine its own alignment from the biggest type it |
| 185 | * contains. |
| 186 | */ |
| 187 | static __inline__ |
| 188 | size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config, |
| 189 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 190 | size_t offset, |
| 191 | size_t *pre_header_padding, |
| 192 | struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 193 | struct lttng_client_ctx *client_ctx) |
| 194 | { |
| 195 | struct lttng_ust_channel_buffer *lttng_chan = channel_get_private(chan); |
| 196 | size_t orig_offset = offset; |
| 197 | size_t padding; |
| 198 | |
| 199 | switch (lttng_chan->priv->header_type) { |
| 200 | case 1: /* compact */ |
| 201 | padding = lttng_ust_lib_ring_buffer_align(offset, lttng_ust_rb_alignof(uint32_t)); |
| 202 | offset += padding; |
| 203 | if (!(ctx->priv->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) { |
| 204 | offset += sizeof(uint32_t); /* id and timestamp */ |
| 205 | } else { |
| 206 | /* Minimum space taken by LTTNG_COMPACT_EVENT_BITS id */ |
| 207 | offset += (LTTNG_COMPACT_EVENT_BITS + CHAR_BIT - 1) / CHAR_BIT; |
| 208 | /* Align extended struct on largest member */ |
| 209 | offset += lttng_ust_lib_ring_buffer_align(offset, lttng_ust_rb_alignof(uint64_t)); |
| 210 | offset += sizeof(uint32_t); /* id */ |
| 211 | offset += lttng_ust_lib_ring_buffer_align(offset, lttng_ust_rb_alignof(uint64_t)); |
| 212 | offset += sizeof(uint64_t); /* timestamp */ |
| 213 | } |
| 214 | break; |
| 215 | case 2: /* large */ |
| 216 | padding = lttng_ust_lib_ring_buffer_align(offset, lttng_ust_rb_alignof(uint16_t)); |
| 217 | offset += padding; |
| 218 | offset += sizeof(uint16_t); |
| 219 | if (!(ctx->priv->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) { |
| 220 | offset += lttng_ust_lib_ring_buffer_align(offset, lttng_ust_rb_alignof(uint32_t)); |
| 221 | offset += sizeof(uint32_t); /* timestamp */ |
| 222 | } else { |
| 223 | /* Align extended struct on largest member */ |
| 224 | offset += lttng_ust_lib_ring_buffer_align(offset, lttng_ust_rb_alignof(uint64_t)); |
| 225 | offset += sizeof(uint32_t); /* id */ |
| 226 | offset += lttng_ust_lib_ring_buffer_align(offset, lttng_ust_rb_alignof(uint64_t)); |
| 227 | offset += sizeof(uint64_t); /* timestamp */ |
| 228 | } |
| 229 | break; |
| 230 | default: |
| 231 | padding = 0; |
| 232 | WARN_ON_ONCE(1); |
| 233 | } |
| 234 | offset += ctx_get_aligned_size(offset, client_ctx->chan_ctx, |
| 235 | client_ctx->packet_context_len); |
| 236 | offset += ctx_get_aligned_size(offset, client_ctx->event_ctx, |
| 237 | client_ctx->event_context_len); |
| 238 | *pre_header_padding = padding; |
| 239 | return offset - orig_offset; |
| 240 | } |
| 241 | |
| 242 | #include "../libringbuffer/api.h" |
| 243 | #include "lttng-rb-clients.h" |
| 244 | |
| 245 | static |
| 246 | void lttng_write_event_header_slow(const struct lttng_ust_lib_ring_buffer_config *config, |
| 247 | struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 248 | struct lttng_client_ctx *client_ctx, |
| 249 | uint32_t event_id); |
| 250 | |
| 251 | /* |
| 252 | * lttng_write_event_header |
| 253 | * |
| 254 | * Writes the event header to the offset (already aligned on 32-bits). |
| 255 | * |
| 256 | * @config: ring buffer instance configuration |
| 257 | * @ctx: reservation context |
| 258 | * @event_id: event ID |
| 259 | */ |
| 260 | static __inline__ |
| 261 | void lttng_write_event_header(const struct lttng_ust_lib_ring_buffer_config *config, |
| 262 | struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 263 | struct lttng_client_ctx *client_ctx, |
| 264 | uint32_t event_id) |
| 265 | { |
| 266 | struct lttng_ust_channel_buffer *lttng_chan = channel_get_private(ctx->priv->chan); |
| 267 | |
| 268 | if (caa_unlikely(ctx->priv->rflags)) |
| 269 | goto slow_path; |
| 270 | |
| 271 | switch (lttng_chan->priv->header_type) { |
| 272 | case 1: /* compact */ |
| 273 | { |
| 274 | uint32_t id_time = 0; |
| 275 | |
| 276 | bt_bitfield_write(&id_time, uint32_t, |
| 277 | 0, |
| 278 | LTTNG_COMPACT_EVENT_BITS, |
| 279 | event_id); |
| 280 | bt_bitfield_write(&id_time, uint32_t, |
| 281 | LTTNG_COMPACT_EVENT_BITS, |
| 282 | LTTNG_COMPACT_TSC_BITS, |
| 283 | ctx->priv->tsc); |
| 284 | lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time)); |
| 285 | break; |
| 286 | } |
| 287 | case 2: /* large */ |
| 288 | { |
| 289 | uint32_t timestamp = (uint32_t) ctx->priv->tsc; |
| 290 | uint16_t id = event_id; |
| 291 | |
| 292 | lib_ring_buffer_write(config, ctx, &id, sizeof(id)); |
| 293 | lttng_ust_lib_ring_buffer_align_ctx(ctx, lttng_ust_rb_alignof(uint32_t)); |
| 294 | lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp)); |
| 295 | break; |
| 296 | } |
| 297 | default: |
| 298 | WARN_ON_ONCE(1); |
| 299 | } |
| 300 | |
| 301 | ctx_record(ctx, lttng_chan, client_ctx->chan_ctx, APP_CTX_ENABLED); |
| 302 | ctx_record(ctx, lttng_chan, client_ctx->event_ctx, APP_CTX_ENABLED); |
| 303 | lttng_ust_lib_ring_buffer_align_ctx(ctx, ctx->largest_align); |
| 304 | |
| 305 | return; |
| 306 | |
| 307 | slow_path: |
| 308 | lttng_write_event_header_slow(config, ctx, client_ctx, event_id); |
| 309 | } |
| 310 | |
| 311 | static |
| 312 | void lttng_write_event_header_slow(const struct lttng_ust_lib_ring_buffer_config *config, |
| 313 | struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 314 | struct lttng_client_ctx *client_ctx, |
| 315 | uint32_t event_id) |
| 316 | { |
| 317 | struct lttng_ust_lib_ring_buffer_ctx_private *ctx_private = ctx->priv; |
| 318 | struct lttng_ust_channel_buffer *lttng_chan = channel_get_private(ctx->priv->chan); |
| 319 | |
| 320 | switch (lttng_chan->priv->header_type) { |
| 321 | case 1: /* compact */ |
| 322 | if (!(ctx_private->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) { |
| 323 | uint32_t id_time = 0; |
| 324 | |
| 325 | bt_bitfield_write(&id_time, uint32_t, |
| 326 | 0, |
| 327 | LTTNG_COMPACT_EVENT_BITS, |
| 328 | event_id); |
| 329 | bt_bitfield_write(&id_time, uint32_t, |
| 330 | LTTNG_COMPACT_EVENT_BITS, |
| 331 | LTTNG_COMPACT_TSC_BITS, |
| 332 | ctx_private->tsc); |
| 333 | lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time)); |
| 334 | } else { |
| 335 | uint8_t id = 0; |
| 336 | uint64_t timestamp = ctx_private->tsc; |
| 337 | |
| 338 | bt_bitfield_write(&id, uint8_t, |
| 339 | 0, |
| 340 | LTTNG_COMPACT_EVENT_BITS, |
| 341 | 31); |
| 342 | lib_ring_buffer_write(config, ctx, &id, sizeof(id)); |
| 343 | /* Align extended struct on largest member */ |
| 344 | lttng_ust_lib_ring_buffer_align_ctx(ctx, lttng_ust_rb_alignof(uint64_t)); |
| 345 | lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id)); |
| 346 | lttng_ust_lib_ring_buffer_align_ctx(ctx, lttng_ust_rb_alignof(uint64_t)); |
| 347 | lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp)); |
| 348 | } |
| 349 | break; |
| 350 | case 2: /* large */ |
| 351 | { |
| 352 | if (!(ctx_private->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTTNG_RFLAG_EXTENDED))) { |
| 353 | uint32_t timestamp = (uint32_t) ctx_private->tsc; |
| 354 | uint16_t id = event_id; |
| 355 | |
| 356 | lib_ring_buffer_write(config, ctx, &id, sizeof(id)); |
| 357 | lttng_ust_lib_ring_buffer_align_ctx(ctx, lttng_ust_rb_alignof(uint32_t)); |
| 358 | lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp)); |
| 359 | } else { |
| 360 | uint16_t id = 65535; |
| 361 | uint64_t timestamp = ctx_private->tsc; |
| 362 | |
| 363 | lib_ring_buffer_write(config, ctx, &id, sizeof(id)); |
| 364 | /* Align extended struct on largest member */ |
| 365 | lttng_ust_lib_ring_buffer_align_ctx(ctx, lttng_ust_rb_alignof(uint64_t)); |
| 366 | lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id)); |
| 367 | lttng_ust_lib_ring_buffer_align_ctx(ctx, lttng_ust_rb_alignof(uint64_t)); |
| 368 | lib_ring_buffer_write(config, ctx, ×tamp, sizeof(timestamp)); |
| 369 | } |
| 370 | break; |
| 371 | } |
| 372 | default: |
| 373 | WARN_ON_ONCE(1); |
| 374 | } |
| 375 | ctx_record(ctx, lttng_chan, client_ctx->chan_ctx, APP_CTX_ENABLED); |
| 376 | ctx_record(ctx, lttng_chan, client_ctx->event_ctx, APP_CTX_ENABLED); |
| 377 | lttng_ust_lib_ring_buffer_align_ctx(ctx, ctx->largest_align); |
| 378 | } |
| 379 | |
| 380 | static const struct lttng_ust_lib_ring_buffer_config client_config; |
| 381 | |
| 382 | static uint64_t client_ring_buffer_clock_read(struct lttng_ust_lib_ring_buffer_channel *chan) |
| 383 | { |
| 384 | return lib_ring_buffer_clock_read(chan); |
| 385 | } |
| 386 | |
| 387 | static |
| 388 | size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config, |
| 389 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 390 | size_t offset, |
| 391 | size_t *pre_header_padding, |
| 392 | struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 393 | void *client_ctx) |
| 394 | { |
| 395 | return record_header_size(config, chan, offset, |
| 396 | pre_header_padding, ctx, client_ctx); |
| 397 | } |
| 398 | |
| 399 | /** |
| 400 | * client_packet_header_size - called on buffer-switch to a new sub-buffer |
| 401 | * |
| 402 | * Return header size without padding after the structure. Don't use packed |
| 403 | * structure because gcc generates inefficient code on some architectures |
| 404 | * (powerpc, mips..) |
| 405 | */ |
| 406 | static size_t client_packet_header_size(void) |
| 407 | { |
| 408 | return offsetof(struct packet_header, ctx.header_end); |
| 409 | } |
| 410 | |
| 411 | static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc, |
| 412 | unsigned int subbuf_idx, |
| 413 | struct lttng_ust_shm_handle *handle) |
| 414 | { |
| 415 | struct lttng_ust_lib_ring_buffer_channel *chan = shmp(handle, buf->backend.chan); |
| 416 | struct packet_header *header = |
| 417 | (struct packet_header *) |
| 418 | lib_ring_buffer_offset_address(&buf->backend, |
| 419 | subbuf_idx * chan->backend.subbuf_size, |
| 420 | handle); |
| 421 | struct lttng_ust_channel_buffer *lttng_chan = channel_get_private(chan); |
| 422 | uint64_t cnt = shmp_index(handle, buf->backend.buf_cnt, subbuf_idx)->seq_cnt; |
| 423 | |
| 424 | assert(header); |
| 425 | if (!header) |
| 426 | return; |
| 427 | header->magic = CTF_MAGIC_NUMBER; |
| 428 | memcpy(header->uuid, lttng_chan->priv->uuid, sizeof(lttng_chan->priv->uuid)); |
| 429 | header->stream_id = lttng_chan->priv->id; |
| 430 | header->stream_instance_id = buf->backend.cpu; |
| 431 | header->ctx.timestamp_begin = tsc; |
| 432 | header->ctx.timestamp_end = 0; |
| 433 | header->ctx.content_size = ~0ULL; /* for debugging */ |
| 434 | header->ctx.packet_size = ~0ULL; |
| 435 | header->ctx.packet_seq_num = chan->backend.num_subbuf * cnt + subbuf_idx; |
| 436 | header->ctx.events_discarded = 0; |
| 437 | header->ctx.cpu_id = buf->backend.cpu; |
| 438 | } |
| 439 | |
| 440 | /* |
| 441 | * offset is assumed to never be 0 here : never deliver a completely empty |
| 442 | * subbuffer. data_size is between 1 and subbuf_size. |
| 443 | */ |
| 444 | static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc, |
| 445 | unsigned int subbuf_idx, unsigned long data_size, |
| 446 | struct lttng_ust_shm_handle *handle) |
| 447 | { |
| 448 | struct lttng_ust_lib_ring_buffer_channel *chan = shmp(handle, buf->backend.chan); |
| 449 | struct packet_header *header = |
| 450 | (struct packet_header *) |
| 451 | lib_ring_buffer_offset_address(&buf->backend, |
| 452 | subbuf_idx * chan->backend.subbuf_size, |
| 453 | handle); |
| 454 | unsigned long records_lost = 0; |
| 455 | |
| 456 | assert(header); |
| 457 | if (!header) |
| 458 | return; |
| 459 | header->ctx.timestamp_end = tsc; |
| 460 | header->ctx.content_size = |
| 461 | (uint64_t) data_size * CHAR_BIT; /* in bits */ |
| 462 | header->ctx.packet_size = |
| 463 | (uint64_t) LTTNG_UST_PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */ |
| 464 | |
| 465 | records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf); |
| 466 | records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf); |
| 467 | records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf); |
| 468 | header->ctx.events_discarded = records_lost; |
| 469 | } |
| 470 | |
| 471 | static int client_buffer_create(struct lttng_ust_lib_ring_buffer *buf, void *priv, |
| 472 | int cpu, const char *name, struct lttng_ust_shm_handle *handle) |
| 473 | { |
| 474 | return 0; |
| 475 | } |
| 476 | |
| 477 | static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf, void *priv, int cpu, struct lttng_ust_shm_handle *handle) |
| 478 | { |
| 479 | } |
| 480 | |
| 481 | static void client_content_size_field(const struct lttng_ust_lib_ring_buffer_config *config, |
| 482 | size_t *offset, size_t *length) |
| 483 | { |
| 484 | *offset = offsetof(struct packet_header, ctx.content_size); |
| 485 | *length = sizeof(((struct packet_header *) NULL)->ctx.content_size); |
| 486 | } |
| 487 | |
| 488 | static void client_packet_size_field(const struct lttng_ust_lib_ring_buffer_config *config, |
| 489 | size_t *offset, size_t *length) |
| 490 | { |
| 491 | *offset = offsetof(struct packet_header, ctx.packet_size); |
| 492 | *length = sizeof(((struct packet_header *) NULL)->ctx.packet_size); |
| 493 | } |
| 494 | |
| 495 | static struct packet_header *client_packet_header(struct lttng_ust_lib_ring_buffer *buf, |
| 496 | struct lttng_ust_shm_handle *handle) |
| 497 | { |
| 498 | return lib_ring_buffer_read_offset_address(&buf->backend, 0, handle); |
| 499 | } |
| 500 | |
| 501 | static int client_timestamp_begin(struct lttng_ust_lib_ring_buffer *buf, |
| 502 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 503 | uint64_t *timestamp_begin) |
| 504 | { |
| 505 | struct lttng_ust_shm_handle *handle = chan->handle; |
| 506 | struct packet_header *header; |
| 507 | |
| 508 | header = client_packet_header(buf, handle); |
| 509 | if (!header) |
| 510 | return -1; |
| 511 | *timestamp_begin = header->ctx.timestamp_begin; |
| 512 | return 0; |
| 513 | } |
| 514 | |
| 515 | static int client_timestamp_end(struct lttng_ust_lib_ring_buffer *buf, |
| 516 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 517 | uint64_t *timestamp_end) |
| 518 | { |
| 519 | struct lttng_ust_shm_handle *handle = chan->handle; |
| 520 | struct packet_header *header; |
| 521 | |
| 522 | header = client_packet_header(buf, handle); |
| 523 | if (!header) |
| 524 | return -1; |
| 525 | *timestamp_end = header->ctx.timestamp_end; |
| 526 | return 0; |
| 527 | } |
| 528 | |
| 529 | static int client_events_discarded(struct lttng_ust_lib_ring_buffer *buf, |
| 530 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 531 | uint64_t *events_discarded) |
| 532 | { |
| 533 | struct lttng_ust_shm_handle *handle = chan->handle; |
| 534 | struct packet_header *header; |
| 535 | |
| 536 | header = client_packet_header(buf, handle); |
| 537 | if (!header) |
| 538 | return -1; |
| 539 | *events_discarded = header->ctx.events_discarded; |
| 540 | return 0; |
| 541 | } |
| 542 | |
| 543 | static int client_content_size(struct lttng_ust_lib_ring_buffer *buf, |
| 544 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 545 | uint64_t *content_size) |
| 546 | { |
| 547 | struct lttng_ust_shm_handle *handle = chan->handle; |
| 548 | struct packet_header *header; |
| 549 | |
| 550 | header = client_packet_header(buf, handle); |
| 551 | if (!header) |
| 552 | return -1; |
| 553 | *content_size = header->ctx.content_size; |
| 554 | return 0; |
| 555 | } |
| 556 | |
| 557 | static int client_packet_size(struct lttng_ust_lib_ring_buffer *buf, |
| 558 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 559 | uint64_t *packet_size) |
| 560 | { |
| 561 | struct lttng_ust_shm_handle *handle = chan->handle; |
| 562 | struct packet_header *header; |
| 563 | |
| 564 | header = client_packet_header(buf, handle); |
| 565 | if (!header) |
| 566 | return -1; |
| 567 | *packet_size = header->ctx.packet_size; |
| 568 | return 0; |
| 569 | } |
| 570 | |
| 571 | static int client_stream_id(struct lttng_ust_lib_ring_buffer *buf, |
| 572 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 573 | uint64_t *stream_id) |
| 574 | { |
| 575 | struct lttng_ust_channel_buffer *lttng_chan = channel_get_private(chan); |
| 576 | |
| 577 | *stream_id = lttng_chan->priv->id; |
| 578 | |
| 579 | return 0; |
| 580 | } |
| 581 | |
| 582 | static int client_current_timestamp(struct lttng_ust_lib_ring_buffer *buf, |
| 583 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 584 | uint64_t *ts) |
| 585 | { |
| 586 | *ts = client_ring_buffer_clock_read(chan); |
| 587 | |
| 588 | return 0; |
| 589 | } |
| 590 | |
| 591 | static int client_sequence_number(struct lttng_ust_lib_ring_buffer *buf, |
| 592 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 593 | uint64_t *seq) |
| 594 | { |
| 595 | struct lttng_ust_shm_handle *handle = chan->handle; |
| 596 | struct packet_header *header; |
| 597 | |
| 598 | header = client_packet_header(buf, handle); |
| 599 | if (!header) |
| 600 | return -1; |
| 601 | *seq = header->ctx.packet_seq_num; |
| 602 | return 0; |
| 603 | } |
| 604 | |
| 605 | static int client_instance_id(struct lttng_ust_lib_ring_buffer *buf, |
| 606 | struct lttng_ust_lib_ring_buffer_channel *chan, |
| 607 | uint64_t *id) |
| 608 | { |
| 609 | *id = buf->backend.cpu; |
| 610 | |
| 611 | return 0; |
| 612 | } |
| 613 | |
| 614 | static const |
| 615 | struct lttng_ust_client_lib_ring_buffer_client_cb client_cb = { |
| 616 | .parent = { |
| 617 | .ring_buffer_clock_read = client_ring_buffer_clock_read, |
| 618 | .record_header_size = client_record_header_size, |
| 619 | .subbuffer_header_size = client_packet_header_size, |
| 620 | .buffer_begin = client_buffer_begin, |
| 621 | .buffer_end = client_buffer_end, |
| 622 | .buffer_create = client_buffer_create, |
| 623 | .buffer_finalize = client_buffer_finalize, |
| 624 | .content_size_field = client_content_size_field, |
| 625 | .packet_size_field = client_packet_size_field, |
| 626 | }, |
| 627 | .timestamp_begin = client_timestamp_begin, |
| 628 | .timestamp_end = client_timestamp_end, |
| 629 | .events_discarded = client_events_discarded, |
| 630 | .content_size = client_content_size, |
| 631 | .packet_size = client_packet_size, |
| 632 | .stream_id = client_stream_id, |
| 633 | .current_timestamp = client_current_timestamp, |
| 634 | .sequence_number = client_sequence_number, |
| 635 | .instance_id = client_instance_id, |
| 636 | }; |
| 637 | |
| 638 | static const struct lttng_ust_lib_ring_buffer_config client_config = { |
| 639 | .cb.ring_buffer_clock_read = client_ring_buffer_clock_read, |
| 640 | .cb.record_header_size = client_record_header_size, |
| 641 | .cb.subbuffer_header_size = client_packet_header_size, |
| 642 | .cb.buffer_begin = client_buffer_begin, |
| 643 | .cb.buffer_end = client_buffer_end, |
| 644 | .cb.buffer_create = client_buffer_create, |
| 645 | .cb.buffer_finalize = client_buffer_finalize, |
| 646 | .cb.content_size_field = client_content_size_field, |
| 647 | .cb.packet_size_field = client_packet_size_field, |
| 648 | |
| 649 | .tsc_bits = LTTNG_COMPACT_TSC_BITS, |
| 650 | .alloc = RING_BUFFER_ALLOC_PER_CPU, |
| 651 | .sync = RING_BUFFER_SYNC_GLOBAL, |
| 652 | .mode = RING_BUFFER_MODE_TEMPLATE, |
| 653 | .backend = RING_BUFFER_PAGE, |
| 654 | .output = RING_BUFFER_MMAP, |
| 655 | .oops = RING_BUFFER_OOPS_CONSISTENCY, |
| 656 | .ipi = RING_BUFFER_NO_IPI_BARRIER, |
| 657 | .wakeup = LTTNG_CLIENT_WAKEUP, |
| 658 | .client_type = LTTNG_CLIENT_TYPE, |
| 659 | |
| 660 | .cb_ptr = &client_cb.parent, |
| 661 | }; |
| 662 | |
| 663 | static |
| 664 | struct lttng_ust_channel_buffer *_channel_create(const char *name, |
| 665 | void *buf_addr, |
| 666 | size_t subbuf_size, size_t num_subbuf, |
| 667 | unsigned int switch_timer_interval, |
| 668 | unsigned int read_timer_interval, |
| 669 | unsigned char *uuid, |
| 670 | uint32_t chan_id, |
| 671 | const int *stream_fds, int nr_stream_fds, |
| 672 | int64_t blocking_timeout) |
| 673 | { |
| 674 | struct lttng_ust_abi_channel_config chan_priv_init; |
| 675 | struct lttng_ust_shm_handle *handle; |
| 676 | struct lttng_ust_channel_buffer *lttng_chan_buf; |
| 677 | |
| 678 | lttng_chan_buf = lttng_ust_alloc_channel_buffer(); |
| 679 | if (!lttng_chan_buf) |
| 680 | return NULL; |
| 681 | memcpy(lttng_chan_buf->priv->uuid, uuid, LTTNG_UST_UUID_LEN); |
| 682 | lttng_chan_buf->priv->id = chan_id; |
| 683 | |
| 684 | memset(&chan_priv_init, 0, sizeof(chan_priv_init)); |
| 685 | memcpy(chan_priv_init.uuid, uuid, LTTNG_UST_UUID_LEN); |
| 686 | chan_priv_init.id = chan_id; |
| 687 | |
| 688 | handle = channel_create(&client_config, name, |
| 689 | __alignof__(struct lttng_ust_abi_channel_config), |
| 690 | sizeof(struct lttng_ust_abi_channel_config), |
| 691 | &chan_priv_init, |
| 692 | lttng_chan_buf, buf_addr, subbuf_size, num_subbuf, |
| 693 | switch_timer_interval, read_timer_interval, |
| 694 | stream_fds, nr_stream_fds, blocking_timeout); |
| 695 | if (!handle) |
| 696 | goto error; |
| 697 | lttng_chan_buf->priv->rb_chan = shmp(handle, handle->chan); |
| 698 | return lttng_chan_buf; |
| 699 | |
| 700 | error: |
| 701 | lttng_ust_free_channel_common(lttng_chan_buf->parent); |
| 702 | return NULL; |
| 703 | } |
| 704 | |
| 705 | static |
| 706 | void lttng_channel_destroy(struct lttng_ust_channel_buffer *lttng_chan_buf) |
| 707 | { |
| 708 | channel_destroy(lttng_chan_buf->priv->rb_chan, lttng_chan_buf->priv->rb_chan->handle, 1); |
| 709 | lttng_ust_free_channel_common(lttng_chan_buf->parent); |
| 710 | } |
| 711 | |
| 712 | static |
| 713 | int lttng_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx) |
| 714 | { |
| 715 | struct lttng_ust_event_recorder *event_recorder = ctx->client_priv; |
| 716 | struct lttng_ust_channel_buffer *lttng_chan = event_recorder->chan; |
| 717 | struct lttng_client_ctx client_ctx; |
| 718 | int ret, nesting; |
| 719 | struct lttng_ust_lib_ring_buffer_ctx_private *private_ctx; |
| 720 | uint32_t event_id; |
| 721 | |
| 722 | event_id = event_recorder->priv->id; |
| 723 | client_ctx.chan_ctx = lttng_ust_rcu_dereference(lttng_chan->priv->ctx); |
| 724 | client_ctx.event_ctx = lttng_ust_rcu_dereference(event_recorder->priv->ctx); |
| 725 | /* Compute internal size of context structures. */ |
| 726 | ctx_get_struct_size(client_ctx.chan_ctx, &client_ctx.packet_context_len, |
| 727 | APP_CTX_ENABLED); |
| 728 | ctx_get_struct_size(client_ctx.event_ctx, &client_ctx.event_context_len, |
| 729 | APP_CTX_ENABLED); |
| 730 | |
| 731 | nesting = lib_ring_buffer_nesting_inc(&client_config); |
| 732 | if (nesting < 0) |
| 733 | return -EPERM; |
| 734 | |
| 735 | private_ctx = &private_ctx_stack[nesting]; |
| 736 | memset(private_ctx, 0, sizeof(*private_ctx)); |
| 737 | private_ctx->pub = ctx; |
| 738 | private_ctx->chan = lttng_chan->priv->rb_chan; |
| 739 | |
| 740 | ctx->priv = private_ctx; |
| 741 | |
| 742 | switch (lttng_chan->priv->header_type) { |
| 743 | case 1: /* compact */ |
| 744 | if (event_id > 30) |
| 745 | private_ctx->rflags |= LTTNG_RFLAG_EXTENDED; |
| 746 | break; |
| 747 | case 2: /* large */ |
| 748 | if (event_id > 65534) |
| 749 | private_ctx->rflags |= LTTNG_RFLAG_EXTENDED; |
| 750 | break; |
| 751 | default: |
| 752 | WARN_ON_ONCE(1); |
| 753 | } |
| 754 | |
| 755 | ret = lib_ring_buffer_reserve(&client_config, ctx, &client_ctx); |
| 756 | if (caa_unlikely(ret)) |
| 757 | goto put; |
| 758 | if (lib_ring_buffer_backend_get_pages(&client_config, ctx, |
| 759 | &private_ctx->backend_pages)) { |
| 760 | ret = -EPERM; |
| 761 | goto put; |
| 762 | } |
| 763 | lttng_write_event_header(&client_config, ctx, &client_ctx, event_id); |
| 764 | return 0; |
| 765 | put: |
| 766 | lib_ring_buffer_nesting_dec(&client_config); |
| 767 | return ret; |
| 768 | } |
| 769 | |
| 770 | static |
| 771 | void lttng_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx) |
| 772 | { |
| 773 | lib_ring_buffer_commit(&client_config, ctx); |
| 774 | lib_ring_buffer_nesting_dec(&client_config); |
| 775 | } |
| 776 | |
| 777 | static |
| 778 | void lttng_event_write(struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 779 | const void *src, size_t len, size_t alignment) |
| 780 | { |
| 781 | lttng_ust_lib_ring_buffer_align_ctx(ctx, alignment); |
| 782 | lib_ring_buffer_write(&client_config, ctx, src, len); |
| 783 | } |
| 784 | |
| 785 | static |
| 786 | void lttng_event_strcpy(struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 787 | const char *src, size_t len) |
| 788 | { |
| 789 | lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#'); |
| 790 | } |
| 791 | |
| 792 | static |
| 793 | void lttng_event_pstrcpy_pad(struct lttng_ust_lib_ring_buffer_ctx *ctx, |
| 794 | const char *src, size_t len) |
| 795 | { |
| 796 | lib_ring_buffer_pstrcpy(&client_config, ctx, src, len, '\0'); |
| 797 | } |
| 798 | |
| 799 | static |
| 800 | int lttng_is_finalized(struct lttng_ust_channel_buffer *chan) |
| 801 | { |
| 802 | struct lttng_ust_lib_ring_buffer_channel *rb_chan = chan->priv->rb_chan; |
| 803 | |
| 804 | return lib_ring_buffer_channel_is_finalized(rb_chan); |
| 805 | } |
| 806 | |
| 807 | static |
| 808 | int lttng_is_disabled(struct lttng_ust_channel_buffer *chan) |
| 809 | { |
| 810 | struct lttng_ust_lib_ring_buffer_channel *rb_chan = chan->priv->rb_chan; |
| 811 | |
| 812 | return lib_ring_buffer_channel_is_disabled(rb_chan); |
| 813 | } |
| 814 | |
| 815 | static |
| 816 | int lttng_flush_buffer(struct lttng_ust_channel_buffer *chan) |
| 817 | { |
| 818 | struct lttng_ust_lib_ring_buffer_channel *rb_chan = chan->priv->rb_chan; |
| 819 | struct lttng_ust_lib_ring_buffer *buf; |
| 820 | int cpu; |
| 821 | |
| 822 | for_each_channel_cpu(cpu, rb_chan) { |
| 823 | int shm_fd, wait_fd, wakeup_fd; |
| 824 | uint64_t memory_map_size; |
| 825 | |
| 826 | buf = channel_get_ring_buffer(&client_config, rb_chan, |
| 827 | cpu, rb_chan->handle, &shm_fd, &wait_fd, |
| 828 | &wakeup_fd, &memory_map_size); |
| 829 | lib_ring_buffer_switch(&client_config, buf, |
| 830 | SWITCH_ACTIVE, rb_chan->handle); |
| 831 | } |
| 832 | return 0; |
| 833 | } |
| 834 | |
| 835 | static struct lttng_transport lttng_relay_transport = { |
| 836 | .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap", |
| 837 | .ops = { |
| 838 | .struct_size = sizeof(struct lttng_ust_channel_buffer_ops), |
| 839 | .priv = __LTTNG_COMPOUND_LITERAL(struct lttng_ust_channel_buffer_ops_private, { |
| 840 | .pub = <tng_relay_transport.ops, |
| 841 | .channel_create = _channel_create, |
| 842 | .channel_destroy = lttng_channel_destroy, |
| 843 | .packet_avail_size = NULL, /* Would be racy anyway */ |
| 844 | .is_finalized = lttng_is_finalized, |
| 845 | .is_disabled = lttng_is_disabled, |
| 846 | .flush_buffer = lttng_flush_buffer, |
| 847 | }), |
| 848 | .event_reserve = lttng_event_reserve, |
| 849 | .event_commit = lttng_event_commit, |
| 850 | .event_write = lttng_event_write, |
| 851 | .event_strcpy = lttng_event_strcpy, |
| 852 | .event_pstrcpy_pad = lttng_event_pstrcpy_pad, |
| 853 | }, |
| 854 | .client_config = &client_config, |
| 855 | }; |
| 856 | |
| 857 | void RING_BUFFER_MODE_TEMPLATE_INIT(void) |
| 858 | { |
| 859 | DBG("LTT : ltt ring buffer client \"%s\" init\n", |
| 860 | "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap"); |
| 861 | lttng_fixup_rb_client_tls(); |
| 862 | lttng_transport_register(<tng_relay_transport); |
| 863 | } |
| 864 | |
| 865 | void RING_BUFFER_MODE_TEMPLATE_EXIT(void) |
| 866 | { |
| 867 | DBG("LTT : ltt ring buffer client \"%s\" exit\n", |
| 868 | "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap"); |
| 869 | lttng_transport_unregister(<tng_relay_transport); |
| 870 | } |