#define _LGPL_SOURCE
-#include <common/common.h>
-#include <common/utils.h>
-#include <urcu/rculist.h>
+#include "ctf-trace.hpp"
+#include "lttng-relayd.hpp"
+#include "stream.hpp"
+
+#include <common/common.hpp>
+#include <common/urcu.hpp>
+#include <common/utils.hpp>
-#include "ctf-trace.h"
-#include "lttng-relayd.h"
-#include "stream.h"
+#include <urcu/rculist.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);
+ struct ctf_trace *trace = lttng::utils::container_of(rcu_head, &ctf_trace::rcu_node);
free(trace);
}
* control side.
*/
LTTNG_ASSERT(cds_list_empty(&trace->stream_list));
+ ASSERT_RCU_READ_LOCKED();
+
session_put(trace->session);
- trace->session = NULL;
+ trace->session = nullptr;
free(trace->path);
- trace->path = NULL;
+ trace->path = nullptr;
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);
+ struct ctf_trace *trace = lttng::utils::container_of(ref, &ctf_trace::ref);
int ret;
struct lttng_ht_iter iter;
}
/*
- * Should be called with RCU read-side lock held.
+ * The caller must either:
+ * - hold the RCU read side lock, or
+ * - guarantee the existence of the object by already holding a reference to
+ * the object.
*/
bool ctf_trace_get(struct ctf_trace *trace)
{
- return urcu_ref_get_unless_zero(&trace->ref);
+ const bool ref = urcu_ref_get_unless_zero(&trace->ref);
+
+ if (!ref) {
+ /*
+ * The ref count is already zero. It means the object is being
+ * torn down concurently.
+ * This is only acceptable if we hold the RCU read-side lock,
+ * else it's a logic error.
+ */
+ ASSERT_RCU_READ_LOCKED();
+ }
+
+ return ref;
}
/*
* 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)
+static struct ctf_trace *ctf_trace_create(struct relay_session *session, const char *subpath)
{
struct ctf_trace *trace;
- trace = (ctf_trace *) zmalloc(sizeof(*trace));
+ trace = zmalloc<ctf_trace>();
if (!trace) {
PERROR("Failed to allocate ctf_trace");
goto end;
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);
+ pthread_mutex_init(&trace->lock, nullptr);
+ pthread_mutex_init(&trace->stream_list_lock, nullptr);
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);
+ 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 nullptr;
}
/*
* ctf_trace_put().
*/
struct ctf_trace *ctf_trace_get_by_path_or_create(struct relay_session *session,
- const char *subpath)
+ const char *subpath)
{
struct lttng_ht_node_str *node;
struct lttng_ht_iter iter;
- struct ctf_trace *trace = NULL;
+ struct ctf_trace *trace = nullptr;
- rcu_read_lock();
+ lttng::urcu::read_lock_guard 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);
+ trace = lttng::utils::container_of(node, &ctf_trace::node);
if (!ctf_trace_get(trace)) {
- trace = NULL;
+ trace = nullptr;
}
end:
- rcu_read_unlock();
if (!trace) {
/* Try to create */
trace = ctf_trace_create(session, subpath);
void ctf_trace_put(struct ctf_trace *trace)
{
- rcu_read_lock();
+ lttng::urcu::read_lock_guard 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) {
+ lttng::urcu::read_lock_guard 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.
{
struct relay_viewer_stream *vstream;
- rcu_read_lock();
+ lttng::urcu::read_lock_guard read_lock;
vstream = rcu_dereference(trace->viewer_metadata_stream);
if (!vstream) {
goto end;
}
if (!viewer_stream_get(vstream)) {
- vstream = NULL;
+ vstream = nullptr;
}
end:
- rcu_read_unlock();
return vstream;
}
projects / lttng-tools.git / blobdiff