Message handling communication between a source processor core and destination processor cores

A method for communicating data between at least one source processor core and at least one destination processor core using a message handler having a plurality of message-handling modules and having a bus arrangement that provides a data communication path between said source core, said at least one destination core and said message handler, said method comprising the steps of:

• transmitting a message from a specified source processor core to message-handling modules associated with respective ones of at least two specified destination processor cores;
• modifying an indicator value of a message receipt indicator belonging to a message-handling module associated with either said source processor core or one of said specified destination processor cores to indicate that said message has been received at the corresponding specified destination processor core;
• detecting using a transmission completion detector and in dependence upon said indicator value, that said message has been received by all of said at least two specified destination cores;
• and
• initiating transmission of an acknowledgement signal to said source processor core in response to said transmission completion detector detecting that said message has been received by all of said at least two specified destination cores.

A computer-readable storage medium storing a computer program for controlling a destination processor core within a data processing apparatus operable to communicate data between at least one source processor core and at least one destination processor core using a message handler, each of a plurality of message-handling modules having memory allocated for storage of a message generated by a source processor core and having a bus arrangement that provides a data communication path between said source processor core, said at least one destination core and said message handler, said computer program for controlling said destination processor core comprising:

• message source identifying code operable to access said message handler to establish which of said message-handling modules generated a message notification signal;
• and
• message-notification signal clearing code operable to modify a stored message receipt indicator value in said identified message-handling module and to clear said message-notification signal;
• wherein said message-notification signal clearing code enables a message-handling module to use a transmission completion detector to detect in dependence upon said indicator value that said message has been received by all of said at least two destination processor cores and to initiate transmission of an acknowledgement signal to said source processor core.