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