X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fust-consumer%2Fust-consumer.c;h=a57bf15987d28061bf56a994dfacc0ad882c6ecd;hp=f6add2c2c88327d05f1dd1ce90b49241df74c1f8;hb=87c1611dab332f28b4b72c6ed96cb2a2ef31d5f7;hpb=00e2e675d54dc726a7c8f8887c889cc8ef022003

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index f6add2c2c..a57bf1598 100644
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -56,10 +56,15 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
 	uint64_t metadata_id;
 	struct consumer_relayd_sock_pair *relayd = NULL;
 
+	/* RCU lock for the relayd pointer */
+	rcu_read_lock();
+
 	/* Flag that the current stream if set for network streaming. */
 	if (stream->net_seq_idx != -1) {
 		relayd = consumer_find_relayd(stream->net_seq_idx);
 		if (relayd == NULL) {
+			ERR("UST consumer mmap(), unable to find relay for index %d",
+					stream->net_seq_idx);
 			goto end;
 		}
 	}
@@ -91,12 +96,12 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
 				do {
 					ret = write(outfd, (void *) &metadata_id,
 							sizeof(stream->relayd_stream_id));
-					if (ret < 0) {
-						PERROR("write metadata stream id");
-						written = ret;
-						goto end;
-					}
-				} while (errno == EINTR);
+				} while (ret < 0 && errno == EINTR);
+				if (ret < 0) {
+					PERROR("write metadata stream id");
+					written = ret;
+					goto end;
+				}
 				DBG("Metadata stream id %zu written before data",
 						stream->relayd_stream_id);
 			}
@@ -105,18 +110,15 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
 	}
 
 	while (len > 0) {
-		ret = write(outfd, stream->mmap_base + mmap_offset, len);
+		do {
+			ret = write(outfd, stream->mmap_base + mmap_offset, len);
+		} while (ret < 0 && errno == EINTR);
 		if (ret < 0) {
-			if (errno == EINTR) {
-				/* restart the interrupted system call */
-				continue;
-			} else {
-				PERROR("Error in file write");
-				if (written == 0) {
-					written = ret;
-				}
-				goto end;
+			PERROR("Error in file write");
+			if (written == 0) {
+				written = ret;
 			}
+			goto end;
 		} else if (ret > len) {
 			PERROR("ret %ld > len %lu", ret, len);
 			written += ret;
@@ -142,6 +144,7 @@ end:
 	if (relayd && stream->metadata_flag) {
 		pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
 	}
+	rcu_read_unlock();
 	return written;
 }
 
@@ -213,6 +216,9 @@ int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 		return -ENOENT;
 	}
 
+	/* relayd need RCU read-side lock */
+	rcu_read_lock();
+
 	switch (msg.cmd_type) {
 	case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
 	{
@@ -434,8 +440,9 @@ end:
 	 */
 	do {
 		ret = write(ctx->consumer_poll_pipe[1], "", 1);
-	} while (ret == -1UL && errno == EINTR);
+	} while (ret < 0 && errno == EINTR);
 end_nosignal:
+	rcu_read_unlock();
 	return 0;
 }