--- /dev/null
+/*
+ * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
+ * David Goulet <dgoulet@efficios.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License, version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#define _GNU_SOURCE
+#include <assert.h>
+
+#include <common/common.h>
+#include <common/utils.h>
+
+#include "lttng-relayd.h"
+#include "index.h"
+
+/*
+ * Deferred free of a relay index object. MUST only be called by a call RCU.
+ */
+static void deferred_free_relay_index(struct rcu_head *head)
+{
+ struct relay_index *index =
+ caa_container_of(head, struct relay_index, rcu_node);
+
+ if (index->to_close_fd >= 0) {
+ int ret;
+
+ ret = close(index->to_close_fd);
+ if (ret < 0) {
+ PERROR("Relay index to close fd %d", index->to_close_fd);
+ }
+ }
+
+ relay_index_free(index);
+}
+
+/*
+ * Allocate a new relay index object using the given stream ID and sequence
+ * number as the hash table key.
+ *
+ * Return allocated object or else NULL on error.
+ */
+struct relay_index *relay_index_create(uint64_t stream_id,
+ uint64_t net_seq_num)
+{
+ struct relay_index *index;
+
+ DBG2("Creating relay index with stream id %" PRIu64 " and seqnum %" PRIu64,
+ stream_id, net_seq_num);
+
+ index = zmalloc(sizeof(*index));
+ if (index == NULL) {
+ PERROR("Relay index zmalloc");
+ goto error;
+ }
+
+ index->to_close_fd = -1;
+ lttng_ht_node_init_two_u64(&index->index_n, stream_id, net_seq_num);
+
+error:
+ return index;
+}
+
+/*
+ * Find a relayd index in the given hash table.
+ *
+ * Return index object or else NULL on error.
+ */
+struct relay_index *relay_index_find(uint64_t stream_id, uint64_t net_seq_num)
+{
+ struct lttng_ht_node_two_u64 *node;
+ struct lttng_ht_iter iter;
+ struct lttng_ht_two_u64 key;
+ struct relay_index *index = NULL;
+
+ DBG3("Finding index for stream id %" PRIu64 " and seq_num %" PRIu64,
+ stream_id, net_seq_num);
+
+ key.key1 = stream_id;
+ key.key2 = net_seq_num;
+
+ lttng_ht_lookup(indexes_ht, (void *)(&key), &iter);
+ node = lttng_ht_iter_get_node_two_u64(&iter);
+ if (node == NULL) {
+ goto end;
+ }
+ index = caa_container_of(node, struct relay_index, index_n);
+
+end:
+ DBG2("Index %sfound in HT for stream ID %" PRIu64 " and seqnum %" PRIu64,
+ (index == NULL) ? "NOT " : "", stream_id, net_seq_num);
+ return index;
+}
+
+/*
+ * Add unique relay index to the given hash table. In case of a collision, the
+ * already existing object is put in the given _index variable.
+ *
+ * RCU read side lock MUST be acquired.
+ */
+void relay_index_add(struct relay_index *index, struct relay_index **_index)
+{
+ struct cds_lfht_node *node_ptr;
+
+ assert(index);
+
+ DBG2("Adding relay index with stream id %" PRIu64 " and seqnum %" PRIu64,
+ index->key.key1, index->key.key2);
+
+ node_ptr = cds_lfht_add_unique(indexes_ht->ht,
+ indexes_ht->hash_fct((void *) &index->index_n.key, lttng_ht_seed),
+ indexes_ht->match_fct, (void *) &index->index_n.key,
+ &index->index_n.node);
+ if (node_ptr != &index->index_n.node) {
+ *_index = caa_container_of(node_ptr, struct relay_index, index_n.node);
+ }
+}
+
+/*
+ * Write index on disk to the given fd. Once done error or not, it is removed
+ * from the hash table and destroy the object.
+ *
+ * MUST be called with a RCU read side lock held.
+ *
+ * Return 0 on success else a negative value.
+ */
+int relay_index_write(int fd, struct relay_index *index)
+{
+ int ret;
+ struct lttng_ht_iter iter;
+
+ DBG2("Writing index for stream ID %" PRIu64 " and seq num %" PRIu64
+ " on fd %d", index->key.key1, index->key.key2, fd);
+
+ /* Delete index from hash table. */
+ iter.iter.node = &index->index_n.node;
+ ret = lttng_ht_del(indexes_ht, &iter);
+ assert(!ret);
+ call_rcu(&index->rcu_node, deferred_free_relay_index);
+
+ return index_write(fd, &index->index_data, sizeof(index->index_data));
+}
+
+/*
+ * Free the given index.
+ */
+void relay_index_free(struct relay_index *index)
+{
+ free(index);
+}
+
+/*
+ * Safely free the given index using a call RCU.
+ */
+void relay_index_free_safe(struct relay_index *index)
+{
+ if (!index) {
+ return;
+ }
+
+ call_rcu(&index->rcu_node, deferred_free_relay_index);
+}
+
+/*
+ * Delete index from the given hash table.
+ *
+ * RCU read side lock MUST be acquired.
+ */
+void relay_index_delete(struct relay_index *index)
+{
+ int ret;
+ struct lttng_ht_iter iter;
+
+ DBG3("Relay index with stream ID %" PRIu64 " and seq num %" PRIu64
+ "deleted.", index->key.key1, index->key.key2);
+
+ /* Delete index from hash table. */
+ iter.iter.node = &index->index_n.node;
+ ret = lttng_ht_del(indexes_ht, &iter);
+ assert(!ret);
+}
+
+/*
+ * Destroy every relay index with the given stream id as part of the key.
+ */
+void relay_index_destroy_by_stream_id(uint64_t stream_id)
+{
+ struct lttng_ht_iter iter;
+ struct relay_index *index;
+
+ rcu_read_lock();
+ cds_lfht_for_each_entry(indexes_ht->ht, &iter.iter, index, index_n.node) {
+ if (index->key.key1 == stream_id) {
+ relay_index_delete(index);
+ relay_index_free_safe(index);
+ }
+ }
+ rcu_read_unlock();
+}
projects / lttng-tools.git / blobdiff