consumer: introduce channel lock

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/src/common/consumer-metadata-cache.c b/src/common/consumer-metadata-cache.c
index 0c20e7fc7cbba6850a3337fc4ebb788d3e5d5f84..c6e6c6b164a423b81dace0312ee3c71c9cb3626e 100644 (file)
--- a/src/common/consumer-metadata-cache.c
+++ b/src/common/consumer-metadata-cache.c
@@ -204,6 +204,7 @@ int consumer_metadata_cache_flushed(struct lttng_consumer_channel *channel,
        cache = channel->metadata_cache;
 
        pthread_mutex_lock(&consumer_data.lock);
+       pthread_mutex_lock(&channel->lock);
        pthread_mutex_lock(&channel->metadata_cache->lock);
 
        if (cache->rb_pushed >= offset) {
@@ -224,6 +225,7 @@ int consumer_metadata_cache_flushed(struct lttng_consumer_channel *channel,
        }
 
        pthread_mutex_unlock(&channel->metadata_cache->lock);
+       pthread_mutex_unlock(&channel->lock);
        pthread_mutex_unlock(&consumer_data.lock);
 
        return ret;

diff --git a/src/common/consumer-stream.c b/src/common/consumer-stream.c
index 723ec829f80095ff17bd3e5996540d01d754072a..717e0a7351a49461e4702c872fc91914b8efaffe 100644 (file)
--- a/src/common/consumer-stream.c
+++ b/src/common/consumer-stream.c
@@ -280,6 +280,7 @@ void consumer_stream_destroy(struct lttng_consumer_stream *stream,
                 */
                if (stream->globally_visible) {
                        pthread_mutex_lock(&consumer_data.lock);
+                       pthread_mutex_lock(&stream->chan->lock);
                        pthread_mutex_lock(&stream->lock);
                        /* Remove every reference of the stream in the consumer. */
                        consumer_stream_delete(stream, ht);
@@ -293,6 +294,7 @@ void consumer_stream_destroy(struct lttng_consumer_stream *stream,
                        consumer_data.need_update = 1;
 
                        pthread_mutex_unlock(&stream->lock);
+                       pthread_mutex_unlock(&stream->chan->lock);
                        pthread_mutex_unlock(&consumer_data.lock);
                } else {
                        /*

diff --git a/src/common/consumer.c b/src/common/consumer.c
index 9b544dd112cbc58b4e339a3126b19e83116fd577..57e26dcf86c869982e579e86b73ea3a663c75052 100644 (file)
--- a/src/common/consumer.c
+++ b/src/common/consumer.c
@@ -291,6 +291,7 @@ void consumer_del_channel(struct lttng_consumer_channel *channel)
        DBG("Consumer delete channel key %" PRIu64, channel->key);
 
        pthread_mutex_lock(&consumer_data.lock);
+       pthread_mutex_lock(&channel->lock);
 
        /* Delete streams that might have been left in the stream list. */
        cds_list_for_each_entry_safe(stream, stmp, &channel->streams.head,
@@ -324,6 +325,7 @@ void consumer_del_channel(struct lttng_consumer_channel *channel)
 
        call_rcu(&channel->node.head, free_channel_rcu);
 end:
+       pthread_mutex_unlock(&channel->lock);
        pthread_mutex_unlock(&consumer_data.lock);
 }
 
@@ -547,6 +549,7 @@ static int add_stream(struct lttng_consumer_stream *stream,
        DBG3("Adding consumer stream %" PRIu64, stream->key);
 
        pthread_mutex_lock(&consumer_data.lock);
+       pthread_mutex_lock(&stream->chan->lock);
        pthread_mutex_lock(&stream->lock);
        rcu_read_lock();
 
@@ -584,6 +587,7 @@ static int add_stream(struct lttng_consumer_stream *stream,
 
        rcu_read_unlock();
        pthread_mutex_unlock(&stream->lock);
+       pthread_mutex_unlock(&stream->chan->lock);
        pthread_mutex_unlock(&consumer_data.lock);
 
        return ret;
@@ -832,6 +836,7 @@ struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
        channel->tracefile_size = tracefile_size;
        channel->tracefile_count = tracefile_count;
        channel->monitor = monitor;
+       pthread_mutex_init(&channel->lock, NULL);
 
        /*
         * In monitor mode, the streams associated with the channel will be put in
@@ -877,6 +882,7 @@ int consumer_add_channel(struct lttng_consumer_channel *channel,
        struct lttng_ht_iter iter;
 
        pthread_mutex_lock(&consumer_data.lock);
+       pthread_mutex_lock(&channel->lock);
        rcu_read_lock();
 
        lttng_ht_lookup(consumer_data.channel_ht, &channel->key, &iter);
@@ -893,6 +899,7 @@ int consumer_add_channel(struct lttng_consumer_channel *channel,
 
 end:
        rcu_read_unlock();
+       pthread_mutex_unlock(&channel->lock);
        pthread_mutex_unlock(&consumer_data.lock);
 
        if (!ret && channel->wait_fd != -1 &&
@@ -1852,6 +1859,7 @@ void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,
        }
 
        pthread_mutex_lock(&consumer_data.lock);
+       pthread_mutex_lock(&stream->chan->lock);
        pthread_mutex_lock(&stream->lock);
 
        switch (consumer_data.type) {
@@ -1945,6 +1953,7 @@ end:
        stream->chan->metadata_stream = NULL;
 
        pthread_mutex_unlock(&stream->lock);
+       pthread_mutex_unlock(&stream->chan->lock);
        pthread_mutex_unlock(&consumer_data.lock);
 
        if (free_chan) {
@@ -1972,6 +1981,7 @@ static int add_metadata_stream(struct lttng_consumer_stream *stream,
        DBG3("Adding metadata stream %" PRIu64 " to hash table", stream->key);
 
        pthread_mutex_lock(&consumer_data.lock);
+       pthread_mutex_lock(&stream->chan->lock);
        pthread_mutex_lock(&stream->lock);
 
        /*
@@ -2017,6 +2027,7 @@ static int add_metadata_stream(struct lttng_consumer_stream *stream,
        rcu_read_unlock();
 
        pthread_mutex_unlock(&stream->lock);
+       pthread_mutex_unlock(&stream->chan->lock);
        pthread_mutex_unlock(&consumer_data.lock);
        return ret;
 }

diff --git a/src/common/consumer.h b/src/common/consumer.h
index dd26e51834d5738a653380b0ab8e872902d565ed..3a0c6c8d8f5e3a737e9ce6da64c3fb4e09c4dd21 100644 (file)
--- a/src/common/consumer.h
+++ b/src/common/consumer.h
@@ -168,6 +168,16 @@ struct lttng_consumer_channel {
         * monitor list of the channel.
         */
        unsigned int monitor;
+
+       /*
+        * Channel lock.
+        *
+        * This is nested INSIDE the consumer data lock.
+        * This is nested OUTSIDE the metadata cache lock.
+        * This is nested OUTSIDE stream lock.
+        * This is nested OUTSIDE consumer_relayd_sock_pair lock.
+        */
+       pthread_mutex_t lock;
 };
 
 /*
@@ -247,6 +257,7 @@ struct lttng_consumer_stream {
         *
         * This is nested INSIDE the consumer_data lock.
         * This is nested INSIDE the metadata cache lock.
+        * This is nested INSIDE the channel lock.
         * This is nested OUTSIDE consumer_relayd_sock_pair lock.
         */
        pthread_mutex_t lock;

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index b2434eb5a78948da66555e4ce48951c1b776fede..abfe613a710d9733dbff984f49728d0ec00b54f0 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -638,6 +638,7 @@ static int close_metadata(uint64_t chan_key)
        }
 
        pthread_mutex_lock(&consumer_data.lock);
+       pthread_mutex_lock(&channel->lock);
 
        if (cds_lfht_is_node_deleted(&channel->node.node)) {
                goto error_unlock;
@@ -658,6 +659,7 @@ static int close_metadata(uint64_t chan_key)
        }
 
 error_unlock:
+       pthread_mutex_unlock(&channel->lock);
        pthread_mutex_unlock(&consumer_data.lock);
 error:
        return ret;
@@ -1047,7 +1049,7 @@ int lttng_ustconsumer_recv_metadata(int sock, uint64_t key, uint64_t offset,
         * and ultimately try to get rid of this global consumer data lock.
         */
        pthread_mutex_lock(&consumer_data.lock);
-
+       pthread_mutex_lock(&channel->lock);
        pthread_mutex_lock(&channel->metadata_cache->lock);
        ret = consumer_metadata_cache_write(channel, offset, len, metadata_str);
        if (ret < 0) {
@@ -1059,10 +1061,12 @@ int lttng_ustconsumer_recv_metadata(int sock, uint64_t key, uint64_t offset,
                 * waiting for the metadata cache to be flushed.
                 */
                pthread_mutex_unlock(&channel->metadata_cache->lock);
+               pthread_mutex_unlock(&channel->lock);
                pthread_mutex_unlock(&consumer_data.lock);
                goto end_free;
        }
        pthread_mutex_unlock(&channel->metadata_cache->lock);
+       pthread_mutex_unlock(&channel->lock);
        pthread_mutex_unlock(&consumer_data.lock);
 
        while (consumer_metadata_cache_flushed(channel, offset + len)) {