X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=src%2Fcommon%2Fkernel-consumer%2Fkernel-consumer.c;h=b6440bc2aef018102e48dcac2fa20c53b33f86db;hb=90c106c686bee2d1dedf1496140f9291d3b16799;hp=8c0a87737056e4e2e39fa6adadbeb7bccb4305bc;hpb=823a3926b8ecdd9299333b5e7a9dcd0c7ca6aa26;p=lttng-tools.git

diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
index 8c0a87737..b6440bc2a 100644
--- a/src/common/kernel-consumer/kernel-consumer.c
+++ b/src/common/kernel-consumer/kernel-consumer.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2011 Julien Desfossez <julien.desfossez@polymtl.ca>
+ * Copyright (C) 2011 EfficiOS Inc.
  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
@@ -139,7 +139,7 @@ error:
 /*
  * Take a snapshot of all the stream of a channel
  * RCU read-side lock must be held across this function to ensure existence of
- * channel. The channel lock must be held by the caller.
+ * channel.
  *
  * Returns 0 on success, < 0 on error
  */
@@ -154,6 +154,9 @@ static int lttng_kconsumer_snapshot_channel(
 
 	DBG("Kernel consumer snapshot channel %" PRIu64, key);
 
+	/* Prevent channel modifications while we perform the snapshot.*/
+	pthread_mutex_lock(&channel->lock);
+
 	rcu_read_lock();
 
 	/* Splice is not supported yet for channel snapshot. */
@@ -347,13 +350,14 @@ end_unlock:
 	pthread_mutex_unlock(&stream->lock);
 end:
 	rcu_read_unlock();
+	pthread_mutex_unlock(&channel->lock);
 	return ret;
 }
 
 /*
  * Read the whole metadata available for a snapshot.
  * RCU read-side lock must be held across this function to ensure existence of
- * metadata_channel. The channel lock must be held by the caller.
+ * metadata_channel.
  *
  * Returns 0 on success, < 0 on error
  */
@@ -376,7 +380,7 @@ static int lttng_kconsumer_snapshot_metadata(
 	metadata_stream = metadata_channel->metadata_stream;
 	assert(metadata_stream);
 
-	pthread_mutex_lock(&metadata_stream->lock);
+	metadata_stream->read_subbuffer_ops.lock(metadata_stream);
 	assert(metadata_channel->trace_chunk);
 	assert(metadata_stream->trace_chunk);
 
@@ -431,7 +435,7 @@ static int lttng_kconsumer_snapshot_metadata(
 
 	ret = 0;
 error_snapshot:
-	pthread_mutex_unlock(&metadata_stream->lock);
+	metadata_stream->read_subbuffer_ops.unlock(metadata_stream);
 	cds_list_del(&metadata_stream->send_node);
 	consumer_stream_destroy(metadata_stream, NULL);
 	metadata_channel->metadata_stream = NULL;
@@ -961,7 +965,6 @@ error_streams_sent_nosignal:
 			ERR("Channel %" PRIu64 " not found", key);
 			ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
 		} else {
-			pthread_mutex_lock(&channel->lock);
 			if (msg.u.snapshot_channel.metadata == 1) {
 				int ret_snapshot;
 
@@ -989,7 +992,6 @@ error_streams_sent_nosignal:
 					ret_code = LTTCOMM_CONSUMERD_SNAPSHOT_FAILED;
 				}
 			}
-			pthread_mutex_unlock(&channel->lock);
 		}
 		health_code_update();
 
@@ -1604,17 +1606,10 @@ enum get_next_subbuffer_status get_subbuffer_common(
 		 * when there is no data for a finalized stream. Those can be
 		 * combined into a -ENODATA return value.
 		 */
-<<<<<<< HEAD
-		if (ret == -EAGAIN) {
-			ret = -ENODATA;
-		}
-
-=======
 		status = GET_NEXT_SUBBUFFER_STATUS_NO_DATA;
 		goto end;
 	default:
 		status = GET_NEXT_SUBBUFFER_STATUS_ERROR;
->>>>>>> ba6c36321 (Clean-up: consumerd: use a specific status code for get_next_subbuffer)
 		goto end;
 	}