+++ /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/utils.h>
-#include <urcu/rculist.h>
-
-#include "ctf-trace.h"
-#include "lttng-relayd.h"
-#include "stream.h"
-
-static uint64_t last_relay_ctf_trace_id;
-static pthread_mutex_t last_relay_ctf_trace_id_lock = PTHREAD_MUTEX_INITIALIZER;
-
-static void rcu_destroy_ctf_trace(struct rcu_head *rcu_head)
-{
- struct ctf_trace *trace =
- caa_container_of(rcu_head, struct ctf_trace, rcu_node);
-
- free(trace);
-}
-
-/*
- * Destroy a ctf trace and all stream contained in it.
- *
- * MUST be called with the RCU read side lock.
- */
-static void ctf_trace_destroy(struct ctf_trace *trace)
-{
- /*
- * Getting to this point, every stream referenced by that trace
- * have put back their ref since the've been closed by the
- * control side.
- */
- LTTNG_ASSERT(cds_list_empty(&trace->stream_list));
- session_put(trace->session);
- trace->session = NULL;
- free(trace->path);
- trace->path = NULL;
- call_rcu(&trace->rcu_node, rcu_destroy_ctf_trace);
-}
-
-static void ctf_trace_release(struct urcu_ref *ref)
-{
- struct ctf_trace *trace =
- caa_container_of(ref, struct ctf_trace, ref);
- int ret;
- struct lttng_ht_iter iter;
-
- iter.iter.node = &trace->node.node;
- ret = lttng_ht_del(trace->session->ctf_traces_ht, &iter);
- LTTNG_ASSERT(!ret);
- ctf_trace_destroy(trace);
-}
-
-/*
- * Should be called with RCU read-side lock held.
- */
-bool ctf_trace_get(struct ctf_trace *trace)
-{
- return urcu_ref_get_unless_zero(&trace->ref);
-}
-
-/*
- * Create and return an allocated ctf_trace. NULL on error.
- * There is no "open" and "close" for a ctf_trace, but rather just a
- * create and refcounting. Whenever all the streams belonging to a trace
- * put their reference, its refcount drops to 0.
- */
-static struct ctf_trace *ctf_trace_create(struct relay_session *session,
- const char *subpath)
-{
- struct ctf_trace *trace;
-
- trace = zmalloc(sizeof(*trace));
- if (!trace) {
- PERROR("Failed to allocate ctf_trace");
- goto end;
- }
- urcu_ref_init(&trace->ref);
-
- if (!session_get(session)) {
- ERR("Failed to acquire session reference");
- goto error;
- }
- trace->session = session;
- trace->path = strdup(subpath);
- if (!trace->path) {
- goto error;
- }
-
- CDS_INIT_LIST_HEAD(&trace->stream_list);
-
- pthread_mutex_lock(&last_relay_ctf_trace_id_lock);
- trace->id = ++last_relay_ctf_trace_id;
- pthread_mutex_unlock(&last_relay_ctf_trace_id_lock);
-
- lttng_ht_node_init_str(&trace->node, trace->path);
- trace->session = session;
- pthread_mutex_init(&trace->lock, NULL);
- pthread_mutex_init(&trace->stream_list_lock, NULL);
- lttng_ht_add_str(session->ctf_traces_ht, &trace->node);
-
- DBG("Created ctf_trace %" PRIu64 "of session \"%s\" from host \"%s\" with path: %s",
- trace->id, session->session_name, session->hostname,
- subpath);
-
-end:
- return trace;
-error:
- ctf_trace_put(trace);
- return NULL;
-}
-
-/*
- * Return a ctf_trace if found by id in the given hash table else NULL.
- * Hold a reference on the ctf_trace, and must be paired with
- * ctf_trace_put().
- */
-struct ctf_trace *ctf_trace_get_by_path_or_create(struct relay_session *session,
- const char *subpath)
-{
- struct lttng_ht_node_str *node;
- struct lttng_ht_iter iter;
- struct ctf_trace *trace = NULL;
-
- rcu_read_lock();
- lttng_ht_lookup(session->ctf_traces_ht, subpath, &iter);
- node = lttng_ht_iter_get_node_str(&iter);
- if (!node) {
- DBG("CTF Trace path %s not found", subpath);
- goto end;
- }
- trace = caa_container_of(node, struct ctf_trace, node);
- if (!ctf_trace_get(trace)) {
- trace = NULL;
- }
-end:
- rcu_read_unlock();
- if (!trace) {
- /* Try to create */
- trace = ctf_trace_create(session, subpath);
- }
- return trace;
-}
-
-void ctf_trace_put(struct ctf_trace *trace)
-{
- rcu_read_lock();
- urcu_ref_put(&trace->ref, ctf_trace_release);
- rcu_read_unlock();
-}
-
-int ctf_trace_close(struct ctf_trace *trace)
-{
- struct relay_stream *stream;
-
- rcu_read_lock();
- cds_list_for_each_entry_rcu(stream, &trace->stream_list,
- stream_node) {
- /*
- * Close stream since the connection owning the trace is being
- * torn down.
- */
- try_stream_close(stream);
- }
- rcu_read_unlock();
- /*
- * Since all references to the trace are held by its streams, we
- * don't need to do any self-ref put.
- */
- return 0;
-}
-
-struct relay_viewer_stream *ctf_trace_get_viewer_metadata_stream(struct ctf_trace *trace)
-{
- struct relay_viewer_stream *vstream;
-
- rcu_read_lock();
- vstream = rcu_dereference(trace->viewer_metadata_stream);
- if (!vstream) {
- goto end;
- }
- if (!viewer_stream_get(vstream)) {
- vstream = NULL;
- }
-end:
- rcu_read_unlock();
- return vstream;
-}
projects / lttng-tools.git / blobdiff