X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=src%2Fcommon%2Fust-consumer%2Fust-consumer.c;h=61b220ee012a76930d3149be0eba07ba2fef919b;hb=ec6ea7d01adc8a9d1481ba645b282c92ec27208e;hp=6b47ec0c9b2739cb04b07808a03890eee065e2fa;hpb=04ef1097c8f54a151c899c1773ac56907c97694d;p=lttng-tools.git

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index 6b47ec0c9..61b220ee0 100644
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -550,43 +550,6 @@ error:
 	return ret;
 }
 
-/*
- * Write metadata to the given channel using ustctl to convert the string to
- * the ringbuffer.
- * Called only from consumer_metadata_cache_write.
- * The metadata cache lock MUST be acquired to write in the cache.
- *
- * Return 0 on success else a negative value.
- */
-int lttng_ustconsumer_push_metadata(struct lttng_consumer_channel *metadata,
-		const char *metadata_str, uint64_t target_offset, uint64_t len)
-{
-	int ret;
-
-	assert(metadata);
-	assert(metadata_str);
-
-	DBG("UST consumer writing metadata to channel %s", metadata->name);
-
-	if (!metadata->metadata_stream) {
-		ret = 0;
-		goto error;
-	}
-
-	assert(target_offset <= metadata->metadata_cache->max_offset);
-	ret = ustctl_write_metadata_to_channel(metadata->uchan,
-			metadata_str + target_offset, len);
-	if (ret < 0) {
-		ERR("ustctl write metadata fail with ret %d, len %" PRIu64, ret, len);
-		goto error;
-	}
-
-	ustctl_flush_buffer(metadata->metadata_stream->ustream, 1);
-
-error:
-	return ret;
-}
-
 /*
  * Flush channel's streams using the given key to retrieve the channel.
  *
@@ -651,6 +614,7 @@ static int close_metadata(uint64_t chan_key)
 
 	pthread_mutex_lock(&consumer_data.lock);
 	pthread_mutex_lock(&channel->lock);
+	pthread_mutex_lock(&channel->timer_lock);
 
 	if (cds_lfht_is_node_deleted(&channel->node.node)) {
 		goto error_unlock;
@@ -678,6 +642,7 @@ static int close_metadata(uint64_t chan_key)
 	}
 
 error_unlock:
+	pthread_mutex_unlock(&channel->timer_lock);
 	pthread_mutex_unlock(&channel->lock);
 	pthread_mutex_unlock(&consumer_data.lock);
 error:
@@ -1039,17 +1004,6 @@ int lttng_ustconsumer_recv_metadata(int sock, uint64_t key, uint64_t offset,
 		goto end_free;
 	}
 
-	/*
-	 * XXX: The consumer data lock is acquired before calling metadata cache
-	 * write which calls push metadata that MUST be protected by the consumer
-	 * lock in order to be able to check the validity of the metadata stream of
-	 * the channel.
-	 *
-	 * Note that this will be subject to change to better fine grained locking
-	 * 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) {
@@ -1061,13 +1015,9 @@ 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)) {
 		DBG("Waiting for metadata to be flushed");
@@ -1856,6 +1806,12 @@ void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream *stream)
 	}
 }
 
+/*
+ * Please refer to consumer-timer.c before adding any lock within this
+ * function or any of its callees. Timers have a very strict locking
+ * semantic with respect to teardown. Failure to respect this semantic
+ * introduces deadlocks.
+ */
 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data *ctx,
 		struct lttng_consumer_channel *channel)
 {
@@ -1890,6 +1846,7 @@ int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data *ctx,
 			channel->session_id,
 			channel->session_id_per_pid);
 
+	pthread_mutex_lock(&ctx->metadata_socket_lock);
 	ret = lttcomm_send_unix_sock(ctx->consumer_metadata_socket, &request,
 			sizeof(request));
 	if (ret < 0) {
@@ -1955,5 +1912,6 @@ int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data *ctx,
 	ret = 0;
 
 end:
+	pthread_mutex_unlock(&ctx->metadata_socket_lock);
 	return ret;
 }