src/plugins/ctf/lttng-live/data-stream.cpp

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright 2019 Francis Deslauriers <francis.deslauriers@efficios.com>
   5  * Copyright 2016 Philippe Proulx <pproulx@efficios.com>
   6  * Copyright 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   7  * Copyright 2010-2011 EfficiOS Inc. and Linux Foundation
   8  */
   9
  10 #include <glib.h>
  11 #include <inttypes.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14
  15 #include <babeltrace2/babeltrace.h>
  16
  17 #include "common/assert.h"
  18 #include "compat/mman.h" /* IWYU pragma: keep  */
  19 #include "cpp-common/vendor/fmt/format.h"
  20
  21 #include "../common/src/msg-iter/msg-iter.hpp"
  22 #include "data-stream.hpp"
  23
  24 #define STREAM_NAME_PREFIX "stream-"
  25
  26 static enum ctf_msg_iter_medium_status medop_request_bytes(size_t request_sz, uint8_t **buffer_addr,
  27                                                            size_t *buffer_sz, void *data)
  28 {
  29     enum ctf_msg_iter_medium_status status = CTF_MSG_ITER_MEDIUM_STATUS_OK;
  30     lttng_live_stream_iterator *stream = (lttng_live_stream_iterator *) data;
  31     struct lttng_live_trace *trace = stream->trace;
  32     struct lttng_live_session *session = trace->session;
  33     struct lttng_live_msg_iter *live_msg_iter = session->lttng_live_msg_iter;
  34     uint64_t recv_len = 0;
  35     uint64_t len_left;
  36     uint64_t read_len;
  37
  38     BT_ASSERT(request_sz);
  39
  40     if (stream->has_stream_hung_up) {
  41         status = CTF_MSG_ITER_MEDIUM_STATUS_EOF;
  42         goto end;
  43     }
  44
  45     len_left = stream->base_offset + stream->len - stream->offset;
  46     if (!len_left) {
  47         lttng_live_stream_iterator_set_state(stream, LTTNG_LIVE_STREAM_ACTIVE_NO_DATA);
  48         status = CTF_MSG_ITER_MEDIUM_STATUS_AGAIN;
  49         goto end;
  50     }
  51
  52     read_len = MIN(request_sz, stream->buflen);
  53     read_len = MIN(read_len, len_left);
  54     status = lttng_live_get_stream_bytes(live_msg_iter, stream, stream->buf, stream->offset,
  55                                          read_len, &recv_len);
  56     *buffer_addr = stream->buf;
  57     *buffer_sz = recv_len;
  58     stream->offset += recv_len;
  59 end:
  60     return status;
  61 }
  62
  63 static bt_stream *medop_borrow_stream(bt_stream_class *stream_class, int64_t stream_id, void *data)
  64 {
  65     lttng_live_stream_iterator *lttng_live_stream = (lttng_live_stream_iterator *) data;
  66
  67     if (!lttng_live_stream->stream) {
  68         uint64_t stream_class_id = bt_stream_class_get_id(stream_class);
  69
  70         BT_CPPLOGI_SPEC(lttng_live_stream->logger,
  71                         "Creating stream {} (ID: {}) out of stream class {}",
  72                         lttng_live_stream->name->str, stream_id, stream_class_id);
  73
  74         bt_stream *stream;
  75
  76         if (stream_id < 0) {
  77             /*
  78              * No stream instance ID in the stream. It's possible
  79              * to encounter this situation with older version of
  80              * LTTng. In these cases, use the viewer_stream_id that
  81              * is unique for a live viewer session.
  82              */
  83             stream =
  84                 bt_stream_create_with_id(stream_class, lttng_live_stream->trace->trace->libObjPtr(),
  85                                          lttng_live_stream->viewer_stream_id);
  86         } else {
  87             stream = bt_stream_create_with_id(
  88                 stream_class, lttng_live_stream->trace->trace->libObjPtr(), (uint64_t) stream_id);
  89         }
  90
  91         if (!stream) {
  92             BT_CPPLOGE_APPEND_CAUSE_SPEC(
  93                 lttng_live_stream->logger,
  94                 "Cannot create stream {} (stream class ID {}, stream ID {})",
  95                 lttng_live_stream->name->str, stream_class_id, stream_id);
  96             return nullptr;
  97         }
  98
  99         lttng_live_stream->stream = bt2::Stream::Shared::createWithoutRef(stream);
 100         lttng_live_stream->stream->name(lttng_live_stream->name->str);
 101     }
 102
 103     return lttng_live_stream->stream->libObjPtr();
 104 }
 105
 106 static struct ctf_msg_iter_medium_ops medops = {
 107     medop_request_bytes,
 108     nullptr,
 109     nullptr,
 110     medop_borrow_stream,
 111 };
 112
 113 enum lttng_live_iterator_status lttng_live_lazy_msg_init(struct lttng_live_session *session,
 114                                                          bt_self_message_iterator *self_msg_iter)
 115 {
 116     struct lttng_live_component *lttng_live = session->lttng_live_msg_iter->lttng_live_comp;
 117     uint64_t trace_idx, stream_iter_idx;
 118
 119     if (!session->lazy_stream_msg_init) {
 120         return LTTNG_LIVE_ITERATOR_STATUS_OK;
 121     }
 122
 123     BT_CPPLOGD_SPEC(session->logger,
 124                     "Lazily initializing self message iterator for live session: "
 125                     "session-id={}, self-msg-iter-addr={}",
 126                     session->id, fmt::ptr(self_msg_iter));
 127
 128     for (trace_idx = 0; trace_idx < session->traces->len; trace_idx++) {
 129         struct lttng_live_trace *trace =
 130             (lttng_live_trace *) g_ptr_array_index(session->traces, trace_idx);
 131
 132         for (stream_iter_idx = 0; stream_iter_idx < trace->stream_iterators->len;
 133              stream_iter_idx++) {
 134             struct ctf_trace_class *ctf_tc;
 135             struct lttng_live_stream_iterator *stream_iter =
 136                 (lttng_live_stream_iterator *) g_ptr_array_index(trace->stream_iterators,
 137                                                                  stream_iter_idx);
 138
 139             if (stream_iter->msg_iter) {
 140                 continue;
 141             }
 142             ctf_tc = ctf_metadata_decoder_borrow_ctf_trace_class(trace->metadata->decoder.get());
 143             BT_CPPLOGD_SPEC(stream_iter->logger,
 144                             "Creating CTF message iterator: session-id={}, ctf-tc-addr={}, "
 145                             "stream-iter-name={}, self-msg-iter-addr={}",
 146                             session->id, fmt::ptr(ctf_tc), stream_iter->name->str,
 147                             fmt::ptr(self_msg_iter));
 148             stream_iter->msg_iter =
 149                 ctf_msg_iter_create(ctf_tc, lttng_live->max_query_size, medops, stream_iter,
 150                                     self_msg_iter, stream_iter->logger);
 151             if (!stream_iter->msg_iter) {
 152                 BT_CPPLOGE_APPEND_CAUSE_SPEC(stream_iter->logger,
 153                                              "Failed to create CTF message iterator");
 154                 goto error;
 155             }
 156         }
 157     }
 158
 159     session->lazy_stream_msg_init = false;
 160
 161     return LTTNG_LIVE_ITERATOR_STATUS_OK;
 162
 163 error:
 164     return LTTNG_LIVE_ITERATOR_STATUS_ERROR;
 165 }
 166
 167 struct lttng_live_stream_iterator *
 168 lttng_live_stream_iterator_create(struct lttng_live_session *session, uint64_t ctf_trace_id,
 169                                   uint64_t stream_id, bt_self_message_iterator *self_msg_iter)
 170 {
 171     lttng_live_stream_iterator *stream_iter = nullptr;
 172
 173     BT_ASSERT(session);
 174     BT_ASSERT(session->lttng_live_msg_iter);
 175     BT_ASSERT(session->lttng_live_msg_iter->lttng_live_comp);
 176
 177     lttng_live_component *lttng_live = session->lttng_live_msg_iter->lttng_live_comp;
 178     lttng_live_trace *trace =
 179         lttng_live_session_borrow_or_create_trace_by_id(session, ctf_trace_id);
 180     if (!trace) {
 181         BT_CPPLOGE_APPEND_CAUSE_SPEC(session->logger, "Failed to borrow CTF trace.");
 182         goto error;
 183     }
 184
 185     stream_iter = new lttng_live_stream_iterator {session->logger};
 186     stream_iter->trace = trace;
 187     stream_iter->state = LTTNG_LIVE_STREAM_ACTIVE_NO_DATA;
 188     stream_iter->viewer_stream_id = stream_id;
 189
 190     stream_iter->ctf_stream_class_id.is_set = false;
 191     stream_iter->ctf_stream_class_id.value = UINT64_MAX;
 192
 193     stream_iter->last_inactivity_ts.is_set = false;
 194     stream_iter->last_inactivity_ts.value = 0;
 195
 196     if (trace->trace) {
 197         struct ctf_trace_class *ctf_tc =
 198             ctf_metadata_decoder_borrow_ctf_trace_class(trace->metadata->decoder.get());
 199         BT_ASSERT(!stream_iter->msg_iter);
 200         stream_iter->msg_iter =
 201             ctf_msg_iter_create(ctf_tc, lttng_live->max_query_size, medops, stream_iter,
 202                                 self_msg_iter, stream_iter->logger);
 203         if (!stream_iter->msg_iter) {
 204             BT_CPPLOGE_APPEND_CAUSE_SPEC(stream_iter->logger,
 205                                          "Failed to create CTF message iterator");
 206             goto error;
 207         }
 208     }
 209     stream_iter->buf = g_new0(uint8_t, lttng_live->max_query_size);
 210     if (!stream_iter->buf) {
 211         BT_CPPLOGE_APPEND_CAUSE_SPEC(stream_iter->logger,
 212                                      "Failed to allocate live stream iterator buffer");
 213         goto error;
 214     }
 215
 216     stream_iter->buflen = lttng_live->max_query_size;
 217     stream_iter->name = g_string_new(NULL);
 218     if (!stream_iter->name) {
 219         BT_CPPLOGE_APPEND_CAUSE_SPEC(stream_iter->logger,
 220                                      "Failed to allocate live stream iterator name buffer");
 221         goto error;
 222     }
 223
 224     g_string_printf(stream_iter->name, STREAM_NAME_PREFIX "%" PRIu64,
 225                     stream_iter->viewer_stream_id);
 226     g_ptr_array_add(trace->stream_iterators, stream_iter);
 227
 228     /* Track the number of active stream iterator. */
 229     session->lttng_live_msg_iter->active_stream_iter++;
 230
 231     goto end;
 232 error:
 233     lttng_live_stream_iterator_destroy(stream_iter);
 234     stream_iter = NULL;
 235 end:
 236     return stream_iter;
 237 }
 238
 239 void lttng_live_stream_iterator_destroy(struct lttng_live_stream_iterator *stream_iter)
 240 {
 241     if (!stream_iter) {
 242         return;
 243     }
 244
 245     g_free(stream_iter->buf);
 246     if (stream_iter->name) {
 247         g_string_free(stream_iter->name, TRUE);
 248     }
 249
 250     bt_message_put_ref(stream_iter->current_msg);
 251
 252     /* Track the number of active stream iterator. */
 253     stream_iter->trace->session->lttng_live_msg_iter->active_stream_iter--;
 254
 255     delete stream_iter;
 256 }