X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=src%2Fcommon%2Fconsumer%2Fconsumer.c;h=9709705b733b17fe2c53970d60482e964a2027df;hb=c124970bc6f688ba8e13cf21cc9933e291cbb76a;hp=86caf6841d43501521ba0a8865402809bfa2d0b8;hpb=6f1177cf8de79015ed38f48749029c81240b0eb6;p=lttng-tools.git

diff --git a/src/common/consumer/consumer.c b/src/common/consumer/consumer.c
index 86caf6841..9709705b7 100644
--- a/src/common/consumer/consumer.c
+++ b/src/common/consumer/consumer.c
@@ -878,6 +878,43 @@ error:
 	return outfd;
 }
 
+/*
+ * Write a character on the metadata poll pipe to wake the metadata thread.
+ * Returns 0 on success, -1 on error.
+ */
+int consumer_metadata_wakeup_pipe(const struct lttng_consumer_channel *channel)
+{
+	int ret = 0;
+
+	DBG("Waking up metadata poll thread (writing to pipe): channel name = '%s'",
+			channel->name);
+	if (channel->monitor && channel->metadata_stream) {
+		const char dummy = 'c';
+		const ssize_t write_ret = lttng_write(
+				channel->metadata_stream->ust_metadata_poll_pipe[1],
+				&dummy, 1);
+
+		if (write_ret < 1) {
+			if (errno == EWOULDBLOCK) {
+				/*
+				 * This is fine, the metadata poll thread
+				 * is having a hard time keeping-up, but
+				 * it will eventually wake-up and consume
+				 * the available data.
+				 */
+				ret = 0;
+			} else {
+				PERROR("Failed to write to UST metadata pipe while attempting to wake-up the metadata poll thread");
+				ret = -1;
+				goto end;
+			}
+		}
+	}
+
+end:
+	return ret;
+}
+
 /*
  * Trigger a dump of the metadata content. Following/during the succesful
  * completion of this call, the metadata poll thread will start receiving
@@ -1584,7 +1621,6 @@ end:
  * Returns the number of bytes written
  */
 ssize_t lttng_consumer_on_read_subbuffer_mmap(
-		struct lttng_consumer_local_data *ctx,
 		struct lttng_consumer_stream *stream,
 		const struct lttng_buffer_view *buffer,
 		unsigned long padding)
@@ -1687,7 +1723,7 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap(
 	 * receive a ret value that is bigger than len.
 	 */
 	ret = lttng_write(outfd, buffer->data, write_len);
-	DBG("Consumer mmap write() ret %zd (len %lu)", ret, write_len);
+	DBG("Consumer mmap write() ret %zd (len %zu)", ret, write_len);
 	if (ret < 0 || ((size_t) ret != write_len)) {
 		/*
 		 * Report error to caller if nothing was written else at least send the
@@ -3254,7 +3290,7 @@ void *consumer_thread_sessiond_poll(void *data)
 			err = 0;	/* All is OK */
 			goto end;
 		}
-		DBG("received command on sock");
+		DBG("Received command on sock");
 	}
 	/* All is OK */
 	err = 0;
@@ -3315,7 +3351,7 @@ ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 		struct lttng_consumer_local_data *ctx,
 		bool locked_by_caller)
 {
-	ssize_t ret, written_bytes;
+	ssize_t ret, written_bytes = 0;
 	int rotation_ret;
 	struct stream_subbuffer subbuffer = {};
 
@@ -3348,6 +3384,7 @@ ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 		if (ret == -ENODATA) {
 			/* Not an error. */
 			ret = 0;
+			goto sleep_stream;
 		}
 		goto end;
 	}
@@ -3360,24 +3397,10 @@ ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 
 	written_bytes = stream->read_subbuffer_ops.consume_subbuffer(
 			ctx, stream, &subbuffer);
-	/*
-	 * Should write subbuf_size amount of data when network streaming or
-	 * the full padded size when we are not streaming.
-	 */
-	if ((written_bytes != subbuffer.info.data.subbuf_size &&
-			    stream->net_seq_idx != (uint64_t) -1ULL) ||
-			(written_bytes != subbuffer.info.data.padded_subbuf_size &&
-					stream->net_seq_idx ==
-							(uint64_t) -1ULL)) {
-		/*
-		 * Display the error but continue processing to try to
-		 * release the subbuffer. This is a DBG statement
-		 * since this can happen without being a critical
-		 * error.
-		 */
-		DBG("Failed to write to tracefile (written_bytes: %zd != padded subbuffer size: %lu, subbuffer size: %lu)",
-				written_bytes, subbuffer.info.data.subbuf_size,
-				subbuffer.info.data.padded_subbuf_size);
+	if (written_bytes <= 0) {
+		ERR("Error consuming subbuffer: (%zd)", written_bytes);
+		ret = (int) written_bytes;
+		goto error_put_subbuf;
 	}
 
 	ret = stream->read_subbuffer_ops.put_next_subbuffer(stream, &subbuffer);
@@ -3413,6 +3436,7 @@ ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 		goto end;
 	}
 
+sleep_stream:
 	if (stream->read_subbuffer_ops.on_sleep) {
 		stream->read_subbuffer_ops.on_sleep(stream, ctx);
 	}