--- /dev/null
+/*
+ * Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com>
+ * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#define _LGPL_SOURCE
+#include <common/common.h>
+#include <common/index/index.h>
+#include <common/compat/string.h>
+#include <common/utils.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "lttng-relayd.h"
+#include "viewer-stream.h"
+
+static void viewer_stream_destroy(struct relay_viewer_stream *vstream)
+{
+ lttng_trace_chunk_put(vstream->stream_file.trace_chunk);
+ free(vstream->path_name);
+ free(vstream->channel_name);
+ free(vstream);
+}
+
+static void viewer_stream_destroy_rcu(struct rcu_head *head)
+{
+ struct relay_viewer_stream *vstream =
+ caa_container_of(head, struct relay_viewer_stream, rcu_node);
+
+ viewer_stream_destroy(vstream);
+}
+
+/* Relay stream's lock must be held by the caller. */
+struct relay_viewer_stream *viewer_stream_create(struct relay_stream *stream,
+ struct lttng_trace_chunk *trace_chunk,
+ enum lttng_viewer_seek seek_t)
+{
+ struct relay_viewer_stream *vstream = NULL;
+
+ ASSERT_LOCKED(stream->lock);
+
+ vstream = (relay_viewer_stream *) zmalloc(sizeof(*vstream));
+ if (!vstream) {
+ PERROR("relay viewer stream zmalloc");
+ goto error;
+ }
+
+ if (trace_chunk) {
+ const bool acquired_reference = lttng_trace_chunk_get(
+ trace_chunk);
+
+ LTTNG_ASSERT(acquired_reference);
+ }
+
+ vstream->stream_file.trace_chunk = trace_chunk;
+ vstream->path_name = lttng_strndup(stream->path_name, LTTNG_VIEWER_PATH_MAX);
+ if (vstream->path_name == NULL) {
+ PERROR("relay viewer path_name alloc");
+ goto error;
+ }
+ vstream->channel_name = lttng_strndup(stream->channel_name,
+ LTTNG_VIEWER_NAME_MAX);
+ if (vstream->channel_name == NULL) {
+ PERROR("relay viewer channel_name alloc");
+ goto error;
+ }
+
+ if (!stream_get(stream)) {
+ ERR("Cannot get stream");
+ goto error;
+ }
+ vstream->stream = stream;
+
+ if (stream->is_metadata && stream->trace->viewer_metadata_stream) {
+ ERR("Cannot attach viewer metadata stream to trace (busy).");
+ goto error;
+ }
+
+ switch (seek_t) {
+ case LTTNG_VIEWER_SEEK_BEGINNING:
+ {
+ uint64_t seq_tail = tracefile_array_get_seq_tail(stream->tfa);
+
+ if (seq_tail == -1ULL) {
+ /*
+ * Tail may not be initialized yet. Nonetheless, we know
+ * we want to send the first index once it becomes
+ * available.
+ */
+ seq_tail = 0;
+ }
+ vstream->current_tracefile_id =
+ tracefile_array_get_file_index_tail(stream->tfa);
+ vstream->index_sent_seqcount = seq_tail;
+ break;
+ }
+ case LTTNG_VIEWER_SEEK_LAST:
+ vstream->current_tracefile_id =
+ tracefile_array_get_read_file_index_head(stream->tfa);
+ /*
+ * We seek at the very end of each stream, awaiting for
+ * a future packet to eventually come in.
+ *
+ * We don't need to check the head position for -1ULL since the
+ * increment will set it to 0.
+ */
+ vstream->index_sent_seqcount =
+ tracefile_array_get_seq_head(stream->tfa) + 1;
+ break;
+ default:
+ goto error;
+ }
+
+ /*
+ * If we never received an index for the current stream, delay
+ * the opening of the index, otherwise open it right now.
+ */
+ if (stream->index_file == NULL) {
+ vstream->index_file = NULL;
+ } else if (vstream->stream_file.trace_chunk) {
+ const uint32_t connection_major = stream->trace->session->major;
+ const uint32_t connection_minor = stream->trace->session->minor;
+ enum lttng_trace_chunk_status chunk_status;
+
+ chunk_status = lttng_index_file_create_from_trace_chunk_read_only(
+ vstream->stream_file.trace_chunk,
+ stream->path_name,
+ stream->channel_name, stream->tracefile_size,
+ vstream->current_tracefile_id,
+ lttng_to_index_major(connection_major,
+ connection_minor),
+ lttng_to_index_minor(connection_major,
+ connection_minor),
+ true, &vstream->index_file);
+ if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
+ if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_NO_FILE) {
+ vstream->index_file = NULL;
+ } else {
+ goto error;
+ }
+ }
+ }
+
+ /*
+ * If we never received a data file for the current stream, delay the
+ * opening, otherwise open it right now.
+ */
+ if (stream->file && vstream->stream_file.trace_chunk) {
+ int ret;
+ char file_path[LTTNG_PATH_MAX];
+ enum lttng_trace_chunk_status status;
+
+ ret = utils_stream_file_path(stream->path_name,
+ stream->channel_name, stream->tracefile_size,
+ vstream->current_tracefile_id, NULL, file_path,
+ sizeof(file_path));
+ if (ret < 0) {
+ goto error;
+ }
+
+ status = lttng_trace_chunk_open_fs_handle(
+ vstream->stream_file.trace_chunk, file_path,
+ O_RDONLY, 0, &vstream->stream_file.handle,
+ true);
+ if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
+ goto error;
+ }
+ }
+
+ if (seek_t == LTTNG_VIEWER_SEEK_LAST && vstream->index_file) {
+ off_t lseek_ret;
+
+ lseek_ret = fs_handle_seek(
+ vstream->index_file->file, 0, SEEK_END);
+ if (lseek_ret < 0) {
+ goto error;
+ }
+ }
+ if (stream->is_metadata) {
+ rcu_assign_pointer(stream->trace->viewer_metadata_stream,
+ vstream);
+ }
+
+ vstream->last_seen_rotation_count = stream->completed_rotation_count;
+
+ /* Globally visible after the add unique. */
+ lttng_ht_node_init_u64(&vstream->stream_n, stream->stream_handle);
+ urcu_ref_init(&vstream->ref);
+ lttng_ht_add_unique_u64(viewer_streams_ht, &vstream->stream_n);
+
+ return vstream;
+
+error:
+ if (vstream) {
+ viewer_stream_destroy(vstream);
+ }
+ return NULL;
+}
+
+static void viewer_stream_unpublish(struct relay_viewer_stream *vstream)
+{
+ int ret;
+ struct lttng_ht_iter iter;
+
+ iter.iter.node = &vstream->stream_n.node;
+ ret = lttng_ht_del(viewer_streams_ht, &iter);
+ LTTNG_ASSERT(!ret);
+}
+
+static void viewer_stream_release(struct urcu_ref *ref)
+{
+ struct relay_viewer_stream *vstream = caa_container_of(ref,
+ struct relay_viewer_stream, ref);
+
+ if (vstream->stream->is_metadata) {
+ rcu_assign_pointer(vstream->stream->trace->viewer_metadata_stream, NULL);
+ }
+
+ viewer_stream_unpublish(vstream);
+
+ if (vstream->stream_file.handle) {
+ fs_handle_close(vstream->stream_file.handle);
+ vstream->stream_file.handle = NULL;
+ }
+ if (vstream->index_file) {
+ lttng_index_file_put(vstream->index_file);
+ vstream->index_file = NULL;
+ }
+ if (vstream->stream) {
+ stream_put(vstream->stream);
+ vstream->stream = NULL;
+ }
+ lttng_trace_chunk_put(vstream->stream_file.trace_chunk);
+ vstream->stream_file.trace_chunk = NULL;
+ call_rcu(&vstream->rcu_node, viewer_stream_destroy_rcu);
+}
+
+/* Must be called with RCU read-side lock held. */
+bool viewer_stream_get(struct relay_viewer_stream *vstream)
+{
+ return urcu_ref_get_unless_zero(&vstream->ref);
+}
+
+/*
+ * Get viewer stream by id.
+ *
+ * Return viewer stream if found else NULL.
+ */
+struct relay_viewer_stream *viewer_stream_get_by_id(uint64_t id)
+{
+ struct lttng_ht_node_u64 *node;
+ struct lttng_ht_iter iter;
+ struct relay_viewer_stream *vstream = NULL;
+
+ rcu_read_lock();
+ lttng_ht_lookup(viewer_streams_ht, &id, &iter);
+ node = lttng_ht_iter_get_node_u64(&iter);
+ if (!node) {
+ DBG("Relay viewer stream %" PRIu64 " not found", id);
+ goto end;
+ }
+ vstream = caa_container_of(node, struct relay_viewer_stream, stream_n);
+ if (!viewer_stream_get(vstream)) {
+ vstream = NULL;
+ }
+end:
+ rcu_read_unlock();
+ return vstream;
+}
+
+void viewer_stream_put(struct relay_viewer_stream *vstream)
+{
+ rcu_read_lock();
+ urcu_ref_put(&vstream->ref, viewer_stream_release);
+ rcu_read_unlock();
+}
+
+void viewer_stream_close_files(struct relay_viewer_stream *vstream)
+{
+ if (vstream->index_file) {
+ lttng_index_file_put(vstream->index_file);
+ vstream->index_file = NULL;
+ }
+ if (vstream->stream_file.handle) {
+ fs_handle_close(vstream->stream_file.handle);
+ vstream->stream_file.handle = NULL;
+ }
+}
+
+void viewer_stream_sync_tracefile_array_tail(struct relay_viewer_stream *vstream)
+{
+ const struct relay_stream *stream = vstream->stream;
+ uint64_t seq_tail;
+
+ vstream->current_tracefile_id = tracefile_array_get_file_index_tail(stream->tfa);
+ seq_tail = tracefile_array_get_seq_tail(stream->tfa);
+ if (seq_tail == -1ULL) {
+ seq_tail = 0;
+ }
+ vstream->index_sent_seqcount = seq_tail;
+}
+
+/*
+ * Rotate a stream to the next tracefile.
+ *
+ * Must be called with the rstream lock held.
+ * Returns 0 on success, 1 on EOF.
+ */
+int viewer_stream_rotate(struct relay_viewer_stream *vstream)
+{
+ int ret;
+ uint64_t new_id;
+ const struct relay_stream *stream = vstream->stream;
+
+ /* Detect the last tracefile to open. */
+ if (stream->index_received_seqcount
+ == vstream->index_sent_seqcount
+ && stream->trace->session->connection_closed) {
+ ret = 1;
+ goto end;
+ }
+
+ if (stream->tracefile_count == 0) {
+ /* Ignore rotation, there is none to do. */
+ ret = 0;
+ goto end;
+ }
+
+ /*
+ * Try to move to the next file.
+ */
+ new_id = (vstream->current_tracefile_id + 1)
+ % stream->tracefile_count;
+ if (tracefile_array_seq_in_file(stream->tfa, new_id,
+ vstream->index_sent_seqcount)) {
+ vstream->current_tracefile_id = new_id;
+ } else {
+ uint64_t seq_tail = tracefile_array_get_seq_tail(stream->tfa);
+
+ /*
+ * This can only be reached on overwrite, which implies there
+ * has been data written at some point, which will have set the
+ * tail.
+ */
+ LTTNG_ASSERT(seq_tail != -1ULL);
+ /*
+ * We need to resync because we lag behind tail.
+ */
+ vstream->current_tracefile_id =
+ tracefile_array_get_file_index_tail(stream->tfa);
+ vstream->index_sent_seqcount = seq_tail;
+ }
+ viewer_stream_close_files(vstream);
+ ret = 0;
+end:
+ return ret;
+}
+
+void print_viewer_streams(void)
+{
+ struct lttng_ht_iter iter;
+ struct relay_viewer_stream *vstream;
+
+ if (!viewer_streams_ht) {
+ return;
+ }
+
+ rcu_read_lock();
+ cds_lfht_for_each_entry(viewer_streams_ht->ht, &iter.iter, vstream,
+ stream_n.node) {
+ if (!viewer_stream_get(vstream)) {
+ continue;
+ }
+ DBG("vstream %p refcount %ld stream %" PRIu64 " trace %" PRIu64
+ " session %" PRIu64,
+ vstream,
+ vstream->ref.refcount,
+ vstream->stream->stream_handle,
+ vstream->stream->trace->id,
+ vstream->stream->trace->session->id);
+ viewer_stream_put(vstream);
+ }
+ rcu_read_unlock();
+}
projects / lttng-tools.git / blobdiff